Long-term results of conventional radiotherapy versus accelerated hyperfractionated radiotherapy versus concomitant radiotherapy and chemotherapy in locoregionally advanced carcinoma of the oropharynx.

AIMS AND BACKGROUND: To compare conventional fractionation (CF) radiation therapy (RT), arm A, versus a split-course accelerated hyperfractionated schedule (S-AHF), arm B, versus CFRT plus concomitant chemotherapy (CT), arm C, in terms of five-year survival and toxicity for squamous cell tumors of the oropharynx. METHODS AND STUDY DESIGN: Between January 1993 and June 1998, 192 previously untreated patients with stage III and IV oropharyngeal carcinoma (excluding T1N1 and T2N1) were enrolled in a multicenter randomized phase III trial (ORO 93-01). In arms A and C, 66 to 70 Gy in 33 to 35 fractions was administered five days a week for six and a half to seven weeks. In arm B, the dose delivered was 64 to 67.2 Gy in two fractions of 1.6 Gy every day, five days a week, with a planned two-week split at 38.4 Gy. In arm C the CT regimen consisted of three cycles of carboplatin and 5-fluorouracil (CBDCA 75 mg/m2 on days 1 to 4 and 5-FU 1000 mg/m2 i.v. on days 1 to 4 every 28 days). RESULTS: No statistically significant difference was found in five-year overall survival (P = 0.39): 21% for arm A, 21% for arm B, and 40% for arm C. Similarly, there was no statistically significant difference in terms of five-year relapse-free survival: 15% for arm A, 17% for arm B, and 36% for arm C. There was a slight trend towards better five-year locoregional control (P = 0.07) for the combined arm: patients without locoregional relapse were 48% in arm C, 21% in arm A and 18% in arm B. Locoregional control was significantly better when arm C was compared with arms A and B combined (P = 0.02; arm A+B 20%; arm C 48%). Distant metastases were fairly balanced in the three arms (A: 14; B: 9; C: 11), with a tendency towards more frequent isolated distant metastasis development in arm C (8 of 11 [72%] versus 7 of 23 [30%] in arms A+B). Five-year second-tumor-free survival was 85%. The 13 second tumors were equally distributed and were mainly correlated with tobacco and alcohol consumption (five lung, two esophagus, two oral cavity, one larynx, one pancreas, one hepatocarcinoma, one myeloma). Arm C showed slightly more G3+ late side effects involving subcutaneous tissues and mucosa, although significant late sequelae were relatively uncommon and the mucosal side effects were mostly transient. The occurrence of persistent G3 xerostomia was comparable in the three treatment arms. CONCLUSIONS: The results obtained with the combination of CT and RT compared with RT alone did not reach statistical significance, but combined treatment almost doubled the five-year overall survival, relapse-free survival and locoregional control rate. Patients with advanced squamous cell carcinomas of the oropharynx who are medically suitable for the combined approach should be treated with a combination of radiotherapy and chemotherapy. The occurrence of second tumors is relatively common in these patients and may contribute substantially to the causes of death.

Locoregionally advanced carcinoma of the oropharynx: conventional radiotherapy vs. accelerated hyperfractionated radiotherapy vs. concomitant radiotherapy and chemotherapy--a multicenter randomized trial.

PURPOSE: To compare conventional fractionation radiation therapy (RT), Arm A, vs. split-course accelerated hyperfractionated RT (S-AHF), Arm B, vs. conventional fractionation RT plus concomitant chemotherapy (CT), Arm C, in terms of survival and toxicity for advanced, unresectable epidermoid tumors of oropharynx. METHODS AND MATERIALS: Between January 1993 and June 1998, 192 previously untreated patients affected with Stage III and IV oropharyngeal carcinoma (excluding T1N1 and T2N1) were accrued in a multicenter, randomized Phase III trial (ORO 93-01). For Arms A and C, 66-70 Gy in 33-35 fractions, 5 days a week, were administered in 6.5-7 weeks to tumor and positive nodes. In Arm B, the dose delivered to tumor and involved nodes was 64-67.2 Gy, giving 2 fractions of 1.6 Gy every day with an interfraction interval of at least 4 h and preferably 6 h, 5 days a week. At 38.4 Gy, a 2-week split was planned; after the split, RT was resumed with the same modality. In Arm C, CT regimen consisted of carboplatin and 5-fluorouracil (CBDCA 75 mg/m(2), Days 1-4; 5-FU 1,000 mg/m(2) i.v. over 96 h, Days 1-4, recycling every 28 days (at 1st, 5th, and 9th week). RESULTS: No statistically significant difference was detected in overall survival (p = 0.129): 40% Arm A vs. 37% Arm B vs. 51% Arm C were alive at 24 months. Similarly, there was no statistically significant difference in terms of event-free survival (p = 0.196): 20% for Arm A, 19% for Arm B, and 37% for Arm C were event free at 24 months. On the contrary, the 2-year disease-free survival was significantly different among the three arms (p = 0.022), with a superiority for Arm C. At 24 months, the proportion of patients without relapse was 42% for Arm C vs. 23% for Arm A and 20% for Arm B. Patients in Arm A less frequently developed G3+ acute mucositis than their counterparts in Arm B or C (14.7% vs. 40.3% vs. 44%). Regarding the CT-related acute toxicity, apart from 1 case of fatal nephrotoxicity, only hematologic G3+ (Grade 3 or higher) acute sequelae were observed (World Health Organization scale), most commonly leukopenia (22.7%). Arm C showed slightly more G3+ skin, s.c. tissue, and mucosal late side effects (RTOG scale), although significant sequelae were relatively uncommon, and mucosal sequelae were most commonly transient. The occurrence of persistent G3 xerostomia was comparable in all three treatment arms. CONCLUSIONS: The combination of simultaneous CT and RT with the regimen of this trial is better than RT alone in advanced oropharyngeal squamous-cell carcinomas, by increasing disease-free survival. This improvement, however, did not translate into an overall survival improvement, and was associated with a higher incidence of acute morbidity.