Efficacy of weekly cisplatin 40mg/m2 in definitive and adjuvant chemoradiation of head and neck cancer: A retrospective analysis.

Abstract

e16039 Background: When chemotherapy is needed with radiotherapy for head and neck cancers, 3-weekly high dose cisplatin is the regimen that has been used in large randomised trials. Difficulties with this regimen include high rates of toxicities and need for overnight admissions for hydration. Weekly cisplatin has been used in our institute for concurrent chemo radiation (CRT) of head and neck cancers to reduce toxicity and improve compliance. Aim of this study is to examine the efficacy of this approach. Methods: Retrospective review of medical records was undertaken on patients who received radical chemo radiation with weekly cisplatin 40mg/m2 at Townsville Cancer Centre from 2003 to 2009. Statistical analysis was performed using SPSS- version17 and survival probabilities were estimated using the Kaplan-Meier method. Results: Out of the total 102 patients who were eligible for analysis, 62 received definitive CRT and 40 received adjuvant CRT. Median follow-up was 20.1 months (range 5 to 86 months).37.2 % of patients got all the 6 planned doses of cisplatin while 68.6% received at least 5 doses. Only 4 (6.4%) patients had interruption of radiotherapy. For definitive CRT group and adjuvant CRT group, estimated 3-year overall survival was 64.5% (95% CI 51 to 78) and 71.5% (95% CI 53 to 90), respectively. The estimated 3-year disease-specific survival in definitive and adjuvant CRT groups were 70.3 % (95% CI 57 to 84) and 81.6% (95% CI 69 to 94), respectively. The 3-year survival for patients who got 5 or more cycles of chemotherapy was 75.2% (95% CI 63 to 88) compared to 52.6% (95% CI 33 to 72) for those who got less than 5 cycles ( p value =0.018). Conclusions: Despite this being a small retrospective study, survival figures and toxicity profiles of low dose weekly cisplatin are comparable to historical controls using high dose regimens. In addition, radiotherapy interruptions are minimised and it is easy to administer in out patient setting.