Prognostic impact of complete remission after preoperative irradiation of tonsillar carcinoma: A retrospective analysis of the radiumhemmet data, 1980-1995

Purpose: This retrospective study was done to determine the outcome of pati ents with tonsillar carcinoma treated at Radiumhemmet, Karolinska Hospital, between January 1980 and December 1995 with radiotherapy alone or in combi nation with surgery. In addition the importance of tumor remission for pati ent survival was analyzed. Methods and Materials: The analysis is based on 167 previously untreated pa tients with biopsy-proven, invasive tonsillar squamous cell carcinoma of th e tonsillar region. All patients were consecutively admitted to the Departm ent of General Oncology, Radiumhemmet, and treated with curative intent. Th e median follow-up time was 20 months. The median target dose was 64 Gy, de livered in fractions of 2 Gy 5 times weekly. Twenty-eight percent of the pa tients underwent surgery of the primary site and/or neck dissection after r adiotherapy (RT). Results: The overall local control rate for the whole patient group after r adiotherapy was 79%. Probability of survival after 5 years for patients res ponding with complete remission (CR) was 43% and for patients,vith incomple te response (non-CR) 9%, (p < 0.0001). The survival in the non-CR group tre ated with combination therapy was 20 months longer than in patients receivi ng radiotherapy alone (p < 0.0001). There was no statistically significant difference in prediction of long-term survival when the patient population was stratified according to tumor differentiation grade, age, sex, nodal st atus, or treatment time. Conclusion: The strongest clinical predictor of survival was the degree of tumor remission after RT. For the non-CR group receiving combination treatm ent including surgery there was a survival benefit as compared to patients treated with RT alone (p < 0.0001) although there were few long-term surviv ors in this patient group. (C) 1999 Elsevier Science Inc.