Chemotherapy as an adjuvant to surgery in lung cancer

Summary

A preliminary evaluation of an adjuvant chemotherapy is presented. A highly dosed intermittent polychemotherapy consisting of 13 courses of three infusions separated by intervals of a week was administered over 3 years. Each infusion contained 12 mg/kg cyclophosphamide, 12 mg/kg 5-fluorouracil (5-FU), 0.5 mg/kg methotrexate and 0.1 mg/kg vinblastine. In all, 2,442 such infusions were given to 219 patients who had undergone radical surgery for bronchial carcinomas. This treatment was generally well tolerated; the leucopenia rate was within an acceptable range.

A randomized control group consisting of 289 patients treated by radical surgery only was checked and examined at the same intervals as 229 patients who were allocated to the adjuvant chemotherapy group. Comparison of the survival rates of the subdivided treatment groups and control groups, calculated by the life-table method, shows differences in the prognosis, as well as in the effectiveness of the one chemotherapy used. These differences also existed with regard to tumor size (according to TNM stages), to the clinical symptoms (according to the Feinstein classification), and to the histological main tumor types. In the first years after onset of treatment in the groups of patients who had tumors of TNM stages I and II, a difference appears in the life-table curves favoring the chemotherapy-treated patients. In TNM stages III, IV, and C there seems to be an increase in survival rates.

One hypothesis is that the chemotherapy had a greater effect on the more rapidly growing tumors than seems to be the case in the slower-growing tumors. Squamous-cell and adenocarcinomas seem to be unfavorably influenced by this therapy, while a positive therapeutic effect seems observable in the carcinomas of the small-cell and of the other different histological types.

Of the more rapidly growing tumors (Feinstein 3 and 5, subdivided into squamous, adeno-and other cell type tumors) on the other hand, a therapeutic effectiveness of the chemotherapy in squamous-cell tumors too seems apparent.

The necessity of close cooperation with the family physicians is emphasized.

The observable differences of the treatment efficacy in patients with various biologically different tumor types, as seen in this preliminary evaluation, permit the formulation of working hypotheses which could lead to treatment optima for the various tumor types.

Taking into account the length of time necessary to conduct such a trial and to reach meaningful results, it is evident that with the increasing number of treatment possibilities such working hypotheses must be tested within the framework of larger international cooperative study groups.