Cancer of the supraglottic larynx treated by radiotherapy exclusively

Seventy-six cases of squamous cell carcinoma of the supraglottic larynx treated by radiotherapy exclusively and followed for at least 3 years are reported. High doses, close to the maximum tolerable, were used with the shrinking field technique with no attempt at prophylactic whole neck irradiation. T1 and T2 cases represented 40% of the whole group and 40% of the patients presented clinically positive neck disease. This latter group had a significantly lower cure rate (42.8%) than the N0 patients (88.3%). Disease control depended also on the T stage: all 30 T1 and T2 lesions, 18/22 (81.8%) of the T3, and 6/17 (35.3%) of the T4 lesions were controlled. Cord fixation and early cartilage destruction were not a major obstacle for tumor control. Base of tongue involvement and especially the T4 and N3 association were indications of poor prognosis. Adenopathies smaller than 3 cm were controlled in 14/16 cases while nodes greater than or equal to 3 cm were controlled in 5/11 cases. Failures in neck nodes outside the treatment field were encountered in 7% of the cases but as the sole element of failure they represented 5.6%. Absolute survival at 3 years was 69.7% for the whole series while loco-regional control was 74.6%. No patient was salvaged by surgery. Three loco-regional recurrences occurred 3 years after the treatment. Although no lethal complications were encountered severe late reactions were noted in about 20% of the patients with controlled primary lesion, requiring tracheostomy in 4 cases (7%). Treatment guidelines are suggested: T1, T2, & T3 lesions associated with adenopathy smaller than 3 cm should be treated by radiotherapy. Limited extra laryngeal extension especially to cartilage can still be controlled by irradiation. More advanced cases, especially the subcategory of T4 N3 patients, should have a multidisciplinary approach. After high doses of irradiation only limited surgery is permissible.