Inoperable oropharyngeal carcinoma treated with concomitant irradiation, mitomycin C and bleomycin – long term results
Abstract:
Patients with inoperable head and neck tumors were treated concomitantly with radiochemotherapy with mitomycin C and bleomycin in our prospective randomized clinical trial (1991– 1993). For the subgroup of patients with oropharyngeal carcinoma the results with radiochemotherapy were significantly superior to irradiation alone. Such scheme of treatment was then adopted as standard method. Here we present the long-term results and dose- response relationships in patients with inoperable oropharyngeal carcinoma treated by the same radiochemotherapy scheme till 1997. Ninety-five patients with stage III and IV inoperable oropharyngeal squamous cell carcinoma were treated with curative intent, concomitantly with supravoltage irradiation 2 Gy/day 5 times weekly to 60–73 Gy, bleomycin 5 mg 2 times weekly and. one application of mitomycin C 15 mg/m2 after 10 Gy. Logistic dose- response curve was calculated. Median follow-up was 85 months. The loco-regional control, disease- free survival and overall survival at 5 years were 55 %, 51 % and 32 % (95 % CI: 44–67 %, 41–62 %, 22–42 %), respectively. The probability of new primary malignancy at 5 years was 23 %. In multivariate analysis performance status, biological equivalent dose, dose of bleomycin, and stage were identified as independent prognostic factors for loco-regional control, disease-free, and overall survival. Th g-value of dose response curve was 2.86. The outcome of the disease was directly proportional to intensity of irradiation and chemotherapy. It appears that in our concomitant radiochemotherapy MiC increased radioresponsiveness of the tumor by its effect on hypoxic fraction.