44_04
Treatment Selection and Technique: Supraglottic Larynx Carcinoma
Selection of Treatment Modality
Patients with supraglottic laryngeal carcinoma may be considered to be in an early or favorable group suitable for radiation therapy or conservation laryngectomy or an unfavorable group often requiring total laryngectomy.
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Early and Moderately Advanced Supraglottic Lesions
Treatment of the primary lesion for the early group is by external-beam irradiation or supraglottic laryngectomy, with or without adjuvant irradiation (39). Transoral laser excision is effective in experienced hands for small, selected lesions (103). Total laryngectomy is rarely indicated as the initial treatment for this group of patients and is reserved for treatment failures.
Radiation therapy and supraglottic laryngectomy are highly successful modes of therapy for early lesions (39). Approximately 50% of supraglottic laryngectomies performed at the University of Florida have been followed by postoperative irradiation because of neck disease and, less often, positive margins.
The decision to use radiation therapy or supraglottic laryngectomy depends on several factors including the anatomic extent of the tumor, medical condition of the patient, philosophy of the attending physician(s), and the inclination of the patient and family. Overall, about 80% of patients are treated initially by irradiation. Approximately half of the patients seen in our clinic whose lesions are technically suitable for a supraglottic laryngectomy are not suitable for medical reasons (e.g., inadequate pulmonary status or other major medical problems); these patients are treated with radiation therapy.
Analysis of local control by anatomic site within the supraglottic larynx shows no obvious differences in local control by irradiation for similarly staged lesions. Invasion of the pre-epiglottic space is not a contraindication to supraglottic laryngectomy or irradiation. Primary tumor volume based on pretreatment CT is inversely related to local tumor control after radiation therapy (61). A large, bulky infiltrative lesion, especially one with extensive preepiglottic space invasion, is a common reason to select supraglottic laryngectomy.
The status of the neck often determines the selection of treatment of the primary lesion. Patients with clinically negative neck nodes have a high risk for occult neck disease and may be treated by radiation therapy or supraglottic laryngectomy and bilateral selective neck dissections, (levels II–IV).
If a patient has an early-stage primary lesion but advanced neck disease (N2b or N3), combined treatment is frequently necessary to control the neck disease (70). In these cases, the primary lesion is usually treated by irradiation alone, with surgery added to the treatment of the involved neck site(s). If the same patient were treated with supraglottic laryngectomy, neck dissection, and postoperative irradiation, the portals would unnecessarily cover the primary site and the neck. If the patient has early, resectable neck disease (N1 or N2a) and surgery is elected for the primary site, postoperative irradiation is added only because of unexpected findings (e.g., positive margins, multiple positive nodes, or extracapsular extension). We prefer to avoid routine high-dose preoperative or postoperative irradiation in conjunction with a supraglottic laryngectomy because the lymphedema of the remaining larynx may be considerable, although it eventually subsides. However, Lee et al. (54) from M.D. Anderson Cancer Center reported excellent results with combined supraglottic laryngectomy and postoperative irradiation for moderately advanced lesions.
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Advanced Supraglottic Lesions
Although a subset of these patients may be suitable for a supraglottic or supracricoid laryngectomy, total laryngectomy is the main surgical option. Selected advanced lesions, especially those that are mainly exophytic, may be treated by radiation therapy and concomitant chemotherapy (90) with total laryngectomy reserved for irradiation failures.
For patients whose primary lesion is to be treated by a total or partial laryngectomy and who have resectable neck disease, surgery is the initial treatment, and postoperative irradiation is added if needed. If the neck disease is unresectable, preoperative radiation therapy is used. The indications for preoperative and postoperative irradiation have been previously outlined.
Surgical Treatment
Supraglottic Laryngectomy
Supraglottic laryngectomy is voice-sparing surgery that can be used successfully for selected lesions involving the epiglottis, a single arytenoid, the aryepiglottic fold, or the false vocal cord. Extension of the tumor to the true vocal cord, the anterior commissure, or both arytenoids; fixation of the vocal cord; or thyroid or cricoid cartilage invasion precludes supraglottic laryngectomy. The supraglottic laryngectomy may be extended to include the base of the tongue if one lingual artery is preserved.
All patients have difficulty swallowing with a tendency to aspirate immediately after surgery, but almost all learn to swallow again in a short time; motivation and the amount of tissue removed are key factors in learning to swallow again. Preoperatively, adequate pulmonary reserve is evaluated by blood gas determinations, function tests, chest roentgenography, and a work test involving walking the patient up two flights of stairs to determine tolerance to pulmonary stress. The voice quality is generally normal after supraglottic laryngectomy.
Supracricoid Laryngectomy
This procedure is an option for lesions extending from the supraglottis into one or both vocal cords. However, vocal cord fixation is a relative contraindication. At least one arytenoid must be preserved for successful decannulation and phonation. Extension to the cricoid and thyroid cartilage destruction also preclude its use. Phonation and respiratory function are reconstituted by approximating the cricoid to the hyoid (cricohyoidopexy).
Wide-Field Total Laryngectomy
Total laryngectomy is performed as previously described.
Radiation Therapy Technique
The primary lesion and both sides of the neck are treated with opposed lateral portals; wedges are used to compensate for the contour of the neck (Fig. 44.11) (73). The lower neck nodes are irradiated through a separate anterior portal. IMRT may be employed to spare one or both parotids and to avoid a low match line in the occasional patient with a short neck and large shoulders. We currently use the concomitant boost fractionation schedule when employing IMRT.
In the case of clinically positive nodes, an electron beam portal may be used to increase the dose to the posterior cervical nodes after the fields are reduced to avoid the spinal cord at 45 Gy. CT is obtained 4 weeks after completing radiotherapy, and a neck dissection is added if the residual cancer in the nodes is thought to exceed 5%; otherwise the patient is observed and a CT is repeated in 3 months (70).
Patients experience a sore throat, loss of taste, and moderate dryness during irradiation. Edema of the arytenoids may occur and give a sensation of a lump in the throat. Tracheostomy is rarely necessary, even for bulky lesions.
Edema of the larynx may persist for several months to a year. Patients who continue to smoke heighten the side effects of dryness, dysphagia, and hoarseness.
Preoperative and Postoperative Treatment Technique
If total laryngectomy is required and the lesion is resectable, postoperative radiation therapy is preferred because there is no evidence that preoperative irradiation produces any better locoregional control or survival rates than surgery and postoperative radiation therapy. Irradiation is added for close or positive margins, invasion of soft tissues of the neck, significant subglottic extension (1 cm or more), thyroid cartilage invasion, multiple positive nodes, and extracapsular extension. The high-risk areas are usually the base of the tongue and the neck.
The dose for postoperative irradiation as a function of known residual disease is as follows: Negative margins, 60 Gy in 30 fractions; microscopically positive margins, 66 Gy in 33 fractions; and gross residual disease, 70 Gy in 35 fractions. All patients are treated with a continuous course, one fraction per day, 5 days per week. The lower neck is treated with doses to 50 Gy in 25 fractions at Dmax. If there is subglottic extension, the dose to the stoma is boosted with electrons (usually 10 to 14 MeV) for an additional 10 Gy in five fractions. The treatment technique is shown in Fig. 44.10 (2). If postoperative irradiation is added after a supraglottic laryngectomy, the dose is lowered to 55.8 Gy
P.988
given in 1.8 Gy fractions. This dose produces acceptable rates of local control and laryngeal edema (94).
The treatment technique used for preoperative radiation therapy is essentially the same as that used for patients treated with irradiation alone, using doses of 50 to 60 Gy at 1.8 to 2 Gy per fraction. Thereafter, the dose is boosted to areas of unresectable disease (usually the neck) to total doses ranging from 65 to 70 Gy.
Treatment of Recurrence
Failures after supraglottic laryngectomy or radiation therapy can frequently be controlled by further treatment; therefore, recognition of recurrence should be vigorously pursued (39). Salvage of patients with recurrence after combined total laryngectomy and irradiation is uncommon. Stomal recurrences are occasionally controlled by radiation therapy or surgery.
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Results of Treatment
Vocal Cord Cancer
The local control and survival rates after treatment of early-stage glottic carcinoma are depicted in Tables 44.3, 44.4, 44.5 and 44.6 (71). The local control and survival rates are similar for transoral laser excision, open partial laryngectomy, and radiotherapy. Larynx preservation rates are also comparable. Voice quality depends on the amount of tissue removed with partial laryngectomy and is probably similar for patients with limited lesions treated with laser to those undergoing radiotherapy and poorer for patients undergoing open partial laryngectomy (71).
Foote et al. (22) reported on 81 patients who underwent laryngectomy for T3 cancers at the Mayo Clinic between 1970 and 1981. Seventy-five patients underwent a total laryngectomy and 6 underwent a near-total laryngectomy; 53 patients received a neck dissection. No patient underwent adjuvant irradiation or chemotherapy. The 5-year rates of locoregional control, cause-specific survival, and absolute survival were 74%, 74%, and 54%, respectively. The results of definitive radiation therapy patients with T3 glottic carcinoma are depicted in Table 44.7 (85) and are similar to the surgical outcomes reported by Foote et al. (22).
The survival and control rates of patients with T3 fixed-cord lesions treated at the University of Florida are presented in Table 44.8 (67). There was no relationship between subsequent local control and whether the vocal cord remained fixed or became mobile during irradiation. The incidence of severe complications, including those after the initial treatment and any later salvage procedures, was 15% after radiation therapy alone and 15% after surgery alone or combined with adjuvant irradiation. The vocal quality varied from fair to nearly normal.
The results of treatment of T4 vocal cord carcinoma in four surgical series and two radiotherapy series are summarized in Table 44.9 (35).
Parsons et al. (86) reviewed the literature and reported a local control rate of 62% in a series of 87 patients treated with irradiation alone for T4 glottic carcinoma.
Combined-Therapy Results
The proportion of patients suitable for a supraglottic laryngectomy is depicted in Table 44.10 (39). Depending on the referral patterns, a modest subset of patients is suitable for this operation. The extent of neck disease for patients treated with either surgery or radiotherapy is shown in Table 44.11 (39). In general, patients treated with supraglottic laryngectomy appropriately have earlier stage neck disease and would be anticipated to have a lower risk of distant failure and improved survival. The local control rates after transoral laser, radiotherapy, and supraglottic laryngectomy are summarized in Tables 44.12, 44.13 and 44.14, respectively (39). In general, the local control rates after transoral laser excision are fairly good for patients with T1–T2 tumors and tend to deteriorate for those with more advanced disease. The local control rate are excellent for patients selected for supraglottic laryngectomy. However, the incidence of severe complications tends to be higher after supraglottic laryngectomy compared with radiotherapy and transoral laser excision (Table 44.15) (39).
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Follow-Up Policy
Follow-up of patients with early lesions is planned for every 4 to 8 weeks for 2 years, every 3 months for the third year, and every 6 months for years 4 and 5, and then annually for life.
Follow-up of patients with vocal cord or supraglottic larynx lesions treated by radiation therapy or conservative surgery is almost more important than the treatment itself because early detection of recurrence usually results in salvage that may include cure with voice preservation.
If recurrence is suspected but the biopsy is negative, patients are reexamined at 2- to 4-week intervals until the matter is settled. The value of follow-up CT scans for detecting early local recurrence is investigational.
Wagenfeld et al. (112) studied 740 cases of glottic larynx cancer treated from 1965 to 1974 to determine the incidence of second respiratory tract malignancies. There was a minimum follow-up of 5 years. There were 48 second respiratory tract malignancies, although only 14 were expected. Twenty-five were in the lung, and 23 were scattered among other head and neck sites. Only 7 of the 23 second head and neck primary lesions resulted in death; these second lesions were frequently diagnosed in an early stage during routine follow-up for the glottic lesion.
Because the risk of a lethal lung primary lesion is nearly as great as that of dying of an early glottic carcinoma, it makes sense to obtain annual chest roentgenograms. Approximately 50% of patients who receive moderate-to-high dose radiotherapy to the entire thyroid gland will develop hypothyroidism within 5 years, so that thyroid functions are checked every 6 to 12 months and thyroid replacement is initiated if the thyroid-stimulating hormone level begins to rise (27).
Sequelae of Treatment
Surgical Sequelae
Neel et al. (78) reported a 26% incidence of nonfatal complications for cordectomy. Immediate postoperative complications included atelectasis and pneumonia, severe subcutaneous emphysema in the neck, bleeding from the tracheotomy site or larynx, wound complications, and airway obstruction requiring tracheotomy. Late complications included granulation tissue that had to be removed by direct laryngoscopy to exclude recurrences, extrusion of cartilage, laryngeal stenosis, and obstructing laryngeal web.
The postoperative complications and sequelae of hemilaryngectomy include chondritis, wound slough, inadequate glottic closure, and anterior commissure webs (25). The complications associated with supraglottic laryngectomy and total laryngectomy for supraglottic carcinomas include fistula (8%), carotid artery exposure or blowout (3% to 5%), infection or wound sloughing (3% to 7%), and fatal complications (3%) (25). The risk of complications increased if tumor margins were involved by tumor; there was no change in risk associated with age, sex, race, laryngeal site, stage of primary tumor, size of primary tumor, use of low-dose preoperative irradiation, or status of the positive nodes.
The incidence of complications after treatment of supraglottic carcinoma is depicted in Table 44.15 (39).
Radiation Therapy Sequelae
The acute reactions from the treatment of early vocal cord cancer using a tumor dose of 2.25 Gy per day to administer a total dose 63 Gy (60Co, five fractions per week) are relatively mild. During the first 2 to 3 weeks, the voice may improve as the tumor regresses. The voice generally becomes hoarse again because of radiation-induced changes, even though the tumor continues to regress. A mild sore throat develops beginning at the end of the second week, but medication is usually not required. The voice begins to improve approximately 3 weeks after completion of treatment, usually reaching a plateau in 2 to 3 months. Patients with extensive lesions often recover a normal voice, although not as frequently as those with small tumors.
Edema of the larynx is the most common sequela after irradiation for glottic or supraglottic lesions. The rate of clearance of the edema is related to the irradiation dose, volume of tissue irradiated, addition of a neck dissection, continued use of alcohol and tobacco, and size and extent of the original lesion. Edema may be accentuated by a radical neck dissection and may require 6 to 12 months to subside.
Soft tissue necrosis leading to chondritis occurs in fewer than 1% of patients, usually in those who continue to smoke. Soft tissue and cartilage necroses mimic recurrence, with hoarseness, pain, and edema; a laryngectomy may be recommended as a last resort for fear of recurrent cancer, even though biopsy specimens show only necrosis.
Corticosteroids such as dexamethasone (Decadron) have been used to reduce radiation-induced edema after recurrence has been ruled out by biopsy. If ulceration and pain occur, administration of an antibiotic such as tetracycline may help. Of 519 patients with T1N0 or T2N0 vocal cord cancer treated at the University of Florida, 5 (1%) experienced severe complications (60), including total laryngectomy for a suspected local recurrence (1 patient), permanent tracheostomy for edema (3 patients), and a pharyngocutaneous fistula after a salvage total laryngectomy (1 patient).
In patients irradiated for supraglottic carcinoma, sore throat persists 3 to 4 weeks after completion of treatment. There is an associated dry mouth from irradiation of the salivary and parotid glands, a loss of taste, and a sensation of a lump in the throat. It is unusual for patients to require a tracheotomy before irradiation unless severe lymphedema develops at the time of direct laryngoscopy and biopsy. However, in patients who have recovered from the direct laryngoscopy and biopsy without obstruction, a tracheotomy has rarely been required during a fractionated course of radiation therapy.
Patients treated twice a day with 1.2 Gy fractions (continuous-course technique) to total doses of 74.4 to 76.8 Gy usually have more brisk acute reactions than those treated once a day with 2-Gy fractions. Approximately 20% treated with twice-a-day irradiation require temporary gastrostomy feeding tubes because they have difficulty in swallowing (1).
Examples of acute chondritis requiring discontinuation of treatment have not been seen, although most epiglottic lesions exhibit cartilage invasion.
The epiglottis, both suprahyoid and infrahyoid portions, remains thicker than normal for long periods of time, but this is not often associated with difficulty in swallowing, respiratory obstruction, or aspiration. The patient is cautioned to eat and drink slowly until the edema resolves. The false cord and arytenoids may develop some edema.
Lesions of the suprahyoid epiglottis frequently destroy the tip of the epiglottis, and it may require some time for the exposed cartilage to heal. Successful irradiation of infrahyoid epiglottis tumors is not associated with a high rate of necrosis, even though most of these lesions penetrate the porous epiglottic cartilage.
The incidence of severe late complications in 274 patients treated with radiation therapy alone or combined with neck dissection at the University of Florida was 4% (39).
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Selection of Treatment Modality
Patients with supraglottic laryngeal carcinoma may be considered to be in an early or favorable group suitable for radiation therapy or conservation laryngectomy or an unfavorable group often requiring total laryngectomy.
P.986
Early and Moderately Advanced Supraglottic Lesions
Treatment of the primary lesion for the early group is by external-beam irradiation or supraglottic laryngectomy, with or without adjuvant irradiation (39). Transoral laser excision is effective in experienced hands for small, selected lesions (103). Total laryngectomy is rarely indicated as the initial treatment for this group of patients and is reserved for treatment failures.
Radiation therapy and supraglottic laryngectomy are highly successful modes of therapy for early lesions (39). Approximately 50% of supraglottic laryngectomies performed at the University of Florida have been followed by postoperative irradiation because of neck disease and, less often, positive margins.
The decision to use radiation therapy or supraglottic laryngectomy depends on several factors including the anatomic extent of the tumor, medical condition of the patient, philosophy of the attending physician(s), and the inclination of the patient and family. Overall, about 80% of patients are treated initially by irradiation. Approximately half of the patients seen in our clinic whose lesions are technically suitable for a supraglottic laryngectomy are not suitable for medical reasons (e.g., inadequate pulmonary status or other major medical problems); these patients are treated with radiation therapy.
Analysis of local control by anatomic site within the supraglottic larynx shows no obvious differences in local control by irradiation for similarly staged lesions. Invasion of the pre-epiglottic space is not a contraindication to supraglottic laryngectomy or irradiation. Primary tumor volume based on pretreatment CT is inversely related to local tumor control after radiation therapy (61). A large, bulky infiltrative lesion, especially one with extensive preepiglottic space invasion, is a common reason to select supraglottic laryngectomy.
The status of the neck often determines the selection of treatment of the primary lesion. Patients with clinically negative neck nodes have a high risk for occult neck disease and may be treated by radiation therapy or supraglottic laryngectomy and bilateral selective neck dissections, (levels II–IV).
If a patient has an early-stage primary lesion but advanced neck disease (N2b or N3), combined treatment is frequently necessary to control the neck disease (70). In these cases, the primary lesion is usually treated by irradiation alone, with surgery added to the treatment of the involved neck site(s). If the same patient were treated with supraglottic laryngectomy, neck dissection, and postoperative irradiation, the portals would unnecessarily cover the primary site and the neck. If the patient has early, resectable neck disease (N1 or N2a) and surgery is elected for the primary site, postoperative irradiation is added only because of unexpected findings (e.g., positive margins, multiple positive nodes, or extracapsular extension). We prefer to avoid routine high-dose preoperative or postoperative irradiation in conjunction with a supraglottic laryngectomy because the lymphedema of the remaining larynx may be considerable, although it eventually subsides. However, Lee et al. (54) from M.D. Anderson Cancer Center reported excellent results with combined supraglottic laryngectomy and postoperative irradiation for moderately advanced lesions.
P.987
Advanced Supraglottic Lesions
Although a subset of these patients may be suitable for a supraglottic or supracricoid laryngectomy, total laryngectomy is the main surgical option. Selected advanced lesions, especially those that are mainly exophytic, may be treated by radiation therapy and concomitant chemotherapy (90) with total laryngectomy reserved for irradiation failures.
For patients whose primary lesion is to be treated by a total or partial laryngectomy and who have resectable neck disease, surgery is the initial treatment, and postoperative irradiation is added if needed. If the neck disease is unresectable, preoperative radiation therapy is used. The indications for preoperative and postoperative irradiation have been previously outlined.
Surgical Treatment
Supraglottic Laryngectomy
Supraglottic laryngectomy is voice-sparing surgery that can be used successfully for selected lesions involving the epiglottis, a single arytenoid, the aryepiglottic fold, or the false vocal cord. Extension of the tumor to the true vocal cord, the anterior commissure, or both arytenoids; fixation of the vocal cord; or thyroid or cricoid cartilage invasion precludes supraglottic laryngectomy. The supraglottic laryngectomy may be extended to include the base of the tongue if one lingual artery is preserved.
All patients have difficulty swallowing with a tendency to aspirate immediately after surgery, but almost all learn to swallow again in a short time; motivation and the amount of tissue removed are key factors in learning to swallow again. Preoperatively, adequate pulmonary reserve is evaluated by blood gas determinations, function tests, chest roentgenography, and a work test involving walking the patient up two flights of stairs to determine tolerance to pulmonary stress. The voice quality is generally normal after supraglottic laryngectomy.
Supracricoid Laryngectomy
This procedure is an option for lesions extending from the supraglottis into one or both vocal cords. However, vocal cord fixation is a relative contraindication. At least one arytenoid must be preserved for successful decannulation and phonation. Extension to the cricoid and thyroid cartilage destruction also preclude its use. Phonation and respiratory function are reconstituted by approximating the cricoid to the hyoid (cricohyoidopexy).
Wide-Field Total Laryngectomy
Total laryngectomy is performed as previously described.
Radiation Therapy Technique
The primary lesion and both sides of the neck are treated with opposed lateral portals; wedges are used to compensate for the contour of the neck (Fig. 44.11) (73). The lower neck nodes are irradiated through a separate anterior portal. IMRT may be employed to spare one or both parotids and to avoid a low match line in the occasional patient with a short neck and large shoulders. We currently use the concomitant boost fractionation schedule when employing IMRT.
In the case of clinically positive nodes, an electron beam portal may be used to increase the dose to the posterior cervical nodes after the fields are reduced to avoid the spinal cord at 45 Gy. CT is obtained 4 weeks after completing radiotherapy, and a neck dissection is added if the residual cancer in the nodes is thought to exceed 5%; otherwise the patient is observed and a CT is repeated in 3 months (70).
Patients experience a sore throat, loss of taste, and moderate dryness during irradiation. Edema of the arytenoids may occur and give a sensation of a lump in the throat. Tracheostomy is rarely necessary, even for bulky lesions.
Edema of the larynx may persist for several months to a year. Patients who continue to smoke heighten the side effects of dryness, dysphagia, and hoarseness.
Preoperative and Postoperative Treatment Technique
If total laryngectomy is required and the lesion is resectable, postoperative radiation therapy is preferred because there is no evidence that preoperative irradiation produces any better locoregional control or survival rates than surgery and postoperative radiation therapy. Irradiation is added for close or positive margins, invasion of soft tissues of the neck, significant subglottic extension (1 cm or more), thyroid cartilage invasion, multiple positive nodes, and extracapsular extension. The high-risk areas are usually the base of the tongue and the neck.
The dose for postoperative irradiation as a function of known residual disease is as follows: Negative margins, 60 Gy in 30 fractions; microscopically positive margins, 66 Gy in 33 fractions; and gross residual disease, 70 Gy in 35 fractions. All patients are treated with a continuous course, one fraction per day, 5 days per week. The lower neck is treated with doses to 50 Gy in 25 fractions at Dmax. If there is subglottic extension, the dose to the stoma is boosted with electrons (usually 10 to 14 MeV) for an additional 10 Gy in five fractions. The treatment technique is shown in Fig. 44.10 (2). If postoperative irradiation is added after a supraglottic laryngectomy, the dose is lowered to 55.8 Gy
P.988
given in 1.8 Gy fractions. This dose produces acceptable rates of local control and laryngeal edema (94).
The treatment technique used for preoperative radiation therapy is essentially the same as that used for patients treated with irradiation alone, using doses of 50 to 60 Gy at 1.8 to 2 Gy per fraction. Thereafter, the dose is boosted to areas of unresectable disease (usually the neck) to total doses ranging from 65 to 70 Gy.
Treatment of Recurrence
Failures after supraglottic laryngectomy or radiation therapy can frequently be controlled by further treatment; therefore, recognition of recurrence should be vigorously pursued (39). Salvage of patients with recurrence after combined total laryngectomy and irradiation is uncommon. Stomal recurrences are occasionally controlled by radiation therapy or surgery.
P.989
P.990
Results of Treatment
Vocal Cord Cancer
The local control and survival rates after treatment of early-stage glottic carcinoma are depicted in Tables 44.3, 44.4, 44.5 and 44.6 (71). The local control and survival rates are similar for transoral laser excision, open partial laryngectomy, and radiotherapy. Larynx preservation rates are also comparable. Voice quality depends on the amount of tissue removed with partial laryngectomy and is probably similar for patients with limited lesions treated with laser to those undergoing radiotherapy and poorer for patients undergoing open partial laryngectomy (71).
Foote et al. (22) reported on 81 patients who underwent laryngectomy for T3 cancers at the Mayo Clinic between 1970 and 1981. Seventy-five patients underwent a total laryngectomy and 6 underwent a near-total laryngectomy; 53 patients received a neck dissection. No patient underwent adjuvant irradiation or chemotherapy. The 5-year rates of locoregional control, cause-specific survival, and absolute survival were 74%, 74%, and 54%, respectively. The results of definitive radiation therapy patients with T3 glottic carcinoma are depicted in Table 44.7 (85) and are similar to the surgical outcomes reported by Foote et al. (22).
The survival and control rates of patients with T3 fixed-cord lesions treated at the University of Florida are presented in Table 44.8 (67). There was no relationship between subsequent local control and whether the vocal cord remained fixed or became mobile during irradiation. The incidence of severe complications, including those after the initial treatment and any later salvage procedures, was 15% after radiation therapy alone and 15% after surgery alone or combined with adjuvant irradiation. The vocal quality varied from fair to nearly normal.
The results of treatment of T4 vocal cord carcinoma in four surgical series and two radiotherapy series are summarized in Table 44.9 (35).
Parsons et al. (86) reviewed the literature and reported a local control rate of 62% in a series of 87 patients treated with irradiation alone for T4 glottic carcinoma.
Combined-Therapy Results
The proportion of patients suitable for a supraglottic laryngectomy is depicted in Table 44.10 (39). Depending on the referral patterns, a modest subset of patients is suitable for this operation. The extent of neck disease for patients treated with either surgery or radiotherapy is shown in Table 44.11 (39). In general, patients treated with supraglottic laryngectomy appropriately have earlier stage neck disease and would be anticipated to have a lower risk of distant failure and improved survival. The local control rates after transoral laser, radiotherapy, and supraglottic laryngectomy are summarized in Tables 44.12, 44.13 and 44.14, respectively (39). In general, the local control rates after transoral laser excision are fairly good for patients with T1–T2 tumors and tend to deteriorate for those with more advanced disease. The local control rate are excellent for patients selected for supraglottic laryngectomy. However, the incidence of severe complications tends to be higher after supraglottic laryngectomy compared with radiotherapy and transoral laser excision (Table 44.15) (39).
P.991
P.992
P.993
Follow-Up Policy
Follow-up of patients with early lesions is planned for every 4 to 8 weeks for 2 years, every 3 months for the third year, and every 6 months for years 4 and 5, and then annually for life.
Follow-up of patients with vocal cord or supraglottic larynx lesions treated by radiation therapy or conservative surgery is almost more important than the treatment itself because early detection of recurrence usually results in salvage that may include cure with voice preservation.
If recurrence is suspected but the biopsy is negative, patients are reexamined at 2- to 4-week intervals until the matter is settled. The value of follow-up CT scans for detecting early local recurrence is investigational.
Wagenfeld et al. (112) studied 740 cases of glottic larynx cancer treated from 1965 to 1974 to determine the incidence of second respiratory tract malignancies. There was a minimum follow-up of 5 years. There were 48 second respiratory tract malignancies, although only 14 were expected. Twenty-five were in the lung, and 23 were scattered among other head and neck sites. Only 7 of the 23 second head and neck primary lesions resulted in death; these second lesions were frequently diagnosed in an early stage during routine follow-up for the glottic lesion.
Because the risk of a lethal lung primary lesion is nearly as great as that of dying of an early glottic carcinoma, it makes sense to obtain annual chest roentgenograms. Approximately 50% of patients who receive moderate-to-high dose radiotherapy to the entire thyroid gland will develop hypothyroidism within 5 years, so that thyroid functions are checked every 6 to 12 months and thyroid replacement is initiated if the thyroid-stimulating hormone level begins to rise (27).
Sequelae of Treatment
Surgical Sequelae
Neel et al. (78) reported a 26% incidence of nonfatal complications for cordectomy. Immediate postoperative complications included atelectasis and pneumonia, severe subcutaneous emphysema in the neck, bleeding from the tracheotomy site or larynx, wound complications, and airway obstruction requiring tracheotomy. Late complications included granulation tissue that had to be removed by direct laryngoscopy to exclude recurrences, extrusion of cartilage, laryngeal stenosis, and obstructing laryngeal web.
The postoperative complications and sequelae of hemilaryngectomy include chondritis, wound slough, inadequate glottic closure, and anterior commissure webs (25). The complications associated with supraglottic laryngectomy and total laryngectomy for supraglottic carcinomas include fistula (8%), carotid artery exposure or blowout (3% to 5%), infection or wound sloughing (3% to 7%), and fatal complications (3%) (25). The risk of complications increased if tumor margins were involved by tumor; there was no change in risk associated with age, sex, race, laryngeal site, stage of primary tumor, size of primary tumor, use of low-dose preoperative irradiation, or status of the positive nodes.
The incidence of complications after treatment of supraglottic carcinoma is depicted in Table 44.15 (39).
Radiation Therapy Sequelae
The acute reactions from the treatment of early vocal cord cancer using a tumor dose of 2.25 Gy per day to administer a total dose 63 Gy (60Co, five fractions per week) are relatively mild. During the first 2 to 3 weeks, the voice may improve as the tumor regresses. The voice generally becomes hoarse again because of radiation-induced changes, even though the tumor continues to regress. A mild sore throat develops beginning at the end of the second week, but medication is usually not required. The voice begins to improve approximately 3 weeks after completion of treatment, usually reaching a plateau in 2 to 3 months. Patients with extensive lesions often recover a normal voice, although not as frequently as those with small tumors.
Edema of the larynx is the most common sequela after irradiation for glottic or supraglottic lesions. The rate of clearance of the edema is related to the irradiation dose, volume of tissue irradiated, addition of a neck dissection, continued use of alcohol and tobacco, and size and extent of the original lesion. Edema may be accentuated by a radical neck dissection and may require 6 to 12 months to subside.
Soft tissue necrosis leading to chondritis occurs in fewer than 1% of patients, usually in those who continue to smoke. Soft tissue and cartilage necroses mimic recurrence, with hoarseness, pain, and edema; a laryngectomy may be recommended as a last resort for fear of recurrent cancer, even though biopsy specimens show only necrosis.
Corticosteroids such as dexamethasone (Decadron) have been used to reduce radiation-induced edema after recurrence has been ruled out by biopsy. If ulceration and pain occur, administration of an antibiotic such as tetracycline may help. Of 519 patients with T1N0 or T2N0 vocal cord cancer treated at the University of Florida, 5 (1%) experienced severe complications (60), including total laryngectomy for a suspected local recurrence (1 patient), permanent tracheostomy for edema (3 patients), and a pharyngocutaneous fistula after a salvage total laryngectomy (1 patient).
In patients irradiated for supraglottic carcinoma, sore throat persists 3 to 4 weeks after completion of treatment. There is an associated dry mouth from irradiation of the salivary and parotid glands, a loss of taste, and a sensation of a lump in the throat. It is unusual for patients to require a tracheotomy before irradiation unless severe lymphedema develops at the time of direct laryngoscopy and biopsy. However, in patients who have recovered from the direct laryngoscopy and biopsy without obstruction, a tracheotomy has rarely been required during a fractionated course of radiation therapy.
Patients treated twice a day with 1.2 Gy fractions (continuous-course technique) to total doses of 74.4 to 76.8 Gy usually have more brisk acute reactions than those treated once a day with 2-Gy fractions. Approximately 20% treated with twice-a-day irradiation require temporary gastrostomy feeding tubes because they have difficulty in swallowing (1).
Examples of acute chondritis requiring discontinuation of treatment have not been seen, although most epiglottic lesions exhibit cartilage invasion.
The epiglottis, both suprahyoid and infrahyoid portions, remains thicker than normal for long periods of time, but this is not often associated with difficulty in swallowing, respiratory obstruction, or aspiration. The patient is cautioned to eat and drink slowly until the edema resolves. The false cord and arytenoids may develop some edema.
Lesions of the suprahyoid epiglottis frequently destroy the tip of the epiglottis, and it may require some time for the exposed cartilage to heal. Successful irradiation of infrahyoid epiglottis tumors is not associated with a high rate of necrosis, even though most of these lesions penetrate the porous epiglottic cartilage.
The incidence of severe late complications in 274 patients treated with radiation therapy alone or combined with neck dissection at the University of Florida was 4% (39).
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posted by stefanoxx at 6:50 AM
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