Aggressive simultaneous radiochemotherapy with cisplatin and paclitaxel in combination with accelerated hyperfractionated radiotherapy in locally advanced head and neck tumors. Results of a phase I-II trial.

BACKGROUND

Simultaneous radiochemotherapy (sRCT) is the treatment of first choice in locally advanced head and neck cancers. We have tested a very aggressive combination protocol with cisplatin and escalated paclitaxel in combination with accelerated hyperfractionated radiotherapy to assess the maximum tolerated dose (MTD), dose-limiting toxicity (DLT), overall toxicity, and response rate.

PATIENTS AND METHODS

The trial recruited 24 patients (21 males, three females, mean age 57 years) treated at our department from 1998 through 2001. Irradiation was administered in daily doses of 2 Gy up to 30 Gy followed by 1.4 Gy twice daily up to 70.6 Gy to the primary tumor and involved nodes and 51 Gy to the clinically negative regional nodes. The chemotherapy schedule included cisplatin in a fixed dose of 20 mg/m(2) on days 1-5 and 29-33 and paclitaxel at increasing dose levels of 20, 25, 30 mg/m(2) twice weekly over the whole treatment time. Patients were recruited in cohorts of three to six, and the MTD was reached if two out of six patients in one cohort developed DLT. DLT was defined as any grade 4 toxicity or any grade 3 toxicity requiring treatment interruption or unplanned hospitalization or any grade 3 neurotoxicity. We recruited mainly patients with large tumors for this protocol; all patients were stage IV, and the mean tumor volume (primary + metastases) amounted to 72 +/- 61 cm(3). The mean follow-up was 30 months (range 4-39 months).

RESULTS

One early death (peritonitis and sepsis at day 10) occurred, and 23 patients were evaluable for acute toxicity and response. The MTD of paclitaxel was reached at the third dose level (30 mg/m(2) paclitaxel twice weekly). The DLT was severe mucositis grade 3 (n = 1) and skin erythema grade 4 (n = 2). After determining the MTD, another 14 patients were treated at the recommended dose level of paclitaxel with 25 mg/m(2) twice weekly. In summary, 13/23 patients (57%) developed grade 3 and 10/23 (43%) grade 2 mucositis. Two patients (9%) had grade 4, five (22%) grade 3, and 16 (69%) grade 2 dermatitis. One patient died at day 30 of neutropenic infection. In one patient, a grade 2 nephrotoxicity appeared requiring cessation of cisplatin chemotherapy. 18/23 patients (78%) required blood transfusion (1-3 units) and 16/23 (70%) i.v. antibiotics. 14 patients (61%) achieved a complete and nine (39%) a partial remission, yielding an overall response rate of 100%. In summary, six patients died of local tumor progression (n = 2), distant metastases (n = 2), or therapy-related complications (n = 2) during follow-up. The 3-year overall survival was 71%. Tumor volume was not a risk factor for failure in this protocol (mean tumor volume in relapse-free vs. progressive patients 71 +/- 65 cm(3) vs. 64 +/- 38 cm(3)). All patients have, so far, developed only slight late effects (fibrosis, lymphedema) with no grade 3-4 late sequelae.

CONCLUSIONS

This very aggressive sRCT protocol yielded excellent response and survival figures but was associated with a very high rate of acute toxicity (8% therapy-related deaths). A maximal supportive treatment is therefore required.