The Role of Primary Radiotherapy for Squamous Cell Carcinoma of the Supraglottic Larynx

Kim, Won Taek; Kim, Dong Won; Kwon, Byung Hyun; Nam, Ji Ho; Hur, Won Joo

Abstract

BACKGROUND
First of all, this study was performed to assess the result of curative radiotherapy and to evaluate different possible prognostic factors for squamous cell carcinoma of the supraglottic larynx treated at the Pusan National University Hospital. The second goal of this study was by comparing our data with those of other study groups, to determine the better treatment policy of supraglottic cancer in future.
METHODS
AND MATERIALS: Thirty-two patients with squamous cell carcinoma of the supraglottic larynx were treated with radiotherapy at Pusan National University Hospital, from August 1985 to December 1996. Minimum follow-up period was 29 months. Twenty-seven patients (84.4%) were followed up over 5 years. Radiotherapy was delivered with 6 MV photons to the primary laryngeal tumor and regional lymphatics with shrinking field technique. All patients received radiotherapy under conventional fractionated schedule (once a day). Median total tumor dose was 70.2 Gy (range, 55.8 to 75.6 Gy) on primary or gross tumor lesion. Thirteen patients had induction chemotherapy with cisplatin and 5-fluorouracil (1-3 cycles). Patient distribution, according to the different stages, were as follows: stage I, 5/32 (15.6%); stage II, 10/32 (31.3%); stage III, 8/32 (25%); stage IV, 9/32 (28.1%).
RESULTS
The 5-year overall survival rate of the whole series (32 patients) was 51.7%. The overall survival rate at 5-years was 80% in stage I, 66.7% in stage II, 42.9% in stage III, 25% in stage IV ( p= 0.0958). The 5-year local control rates after radiotherapy were as follows: stage I, 100%; stage II, 60%; stage III, 62.5%; stage IV, 44.4% ( p=0.233). Overall vocal preservation rates was 65.6%, 100% in stage I, 70% in stage II, 62.5% in stage III, 44.4% in stage IV ( p=0.210). There was no statistical significance in survival and local control rate between neoadjuvant chemotherapy followed by radiotherapy group and radiotherapy alone group. Severe laryngeal edema was found in 2 cases after radiotherapy, emergent tracheostomy was done. Four patients were died from distant metastsis, : three in lung, one in brain. Double primary tumor was found in 2 cases, one in lung (metachronous), another in thyroid (synchronous). Ulcerative lesions were revealed as unfavorable prognostic factor ( p=0.0215), and radiation dose (more or less than 70.2 Gy) was an important factor on survival ( p=0.0302).
CONCLUSIONS
The role of radiotherapy in the treatment of supraglottic carcinoma is to improve the survival and to preserve the laryngeal function. Based on our data and other studies, early and moderately advanced supraglottic carcinomas could be successfully treated with either conservative surgery or radiotherapy alone. Both modalities showed similar results in survival and vocal preservation. For the advanced cases, radiotherapy alone is inadequate for curative aim and surgery combined with radiotherapy should be done in operable patients. When patients refuse operation or want to preserve vocal function, or for the patients with inoperable medical conditions, combined chemoradiotherapy (concurrent) or altered fractionated radiotherapy with or without radiosensitizer should be taken into consideration in future.