A phase-II evaluation of paclitaxel, carboplatin and radiotherapy in stage III/IV operable cancer of the oropharynx and oral cavity: 1-year results

Purpose : Taxol and carboplatin have both demonstrated excellent radiosensitazation through two mechanisms, namely cell blockage in G2-M phase and inhibition of DNA repair respectively. A prospective Phase II evaluation was initiated using Paclitaxel and carboplatin (CBDCA) with concurrent conventional fractionated external beam radiotherapy followed by surgery of the primary tumor and the regional neck nodes. Methods : From 6/98 - 6/99 twenty-five patients received 5 cycles of weekly Paclitaxel (40 mg/m²), CBDCA (AUC of 1.5) with conventional radiotherapy (40 Gy). Within three to four weeks after chemoradiotherapy surgery was performed. The patient characteristics were as follows : Men 20, women 5 ; mean age 54 (range 40-71) ; Stage III 6, Stage IV 19. Site : oropharynx 4, oral cavity 21. Results : Twenty-one patients were evaluable for toxicity and response. The clinical response was as follows: Complete response (CR) 11/21 (52%); partial response (PR) 10/21 (48%). Eighteen patients (85%) were evaluable for pathologic response after surgical resection. The pathological response was as follows : pCR 10/18 (55%) ; pPR 8/18 (45%). CTC grade 2 or 3 mucositis occured in all twenty-one patients. Other toxicities involved skin [CTC grade 1 (48%),grade 2 (28%), grade 3 (4%)], hemoglobin CTC grade 3 (14%), leukocytes CTC grade 1 (24%). Grade 3 (33%), grade 4 (10%), thrombocytes CTC grade 2 (10%), grade 3 (14%). Conclusion : Concurrent Paclitaxel, carboplatin and radiotherapy resulted in excellent clinical and pathological responses. Mucositis was the most common and significant morbidity. The study is ongoing with a projected number of 30 patients.