Study of cytotoxic chemotherapy as an adjuvant to surgery in carcinoma of the bronchus. Report by a Medical Research Council Working Party.
This report gives the findings after two years of a study of long-term oral cytotoxic chemotherapy with busulphan or cyclophoshamide in carcinoma of the bronchus compared with two placebos, identical in appearance to the drug-containing tablets. A total of 753 patients who had had a total resection of the tumour, who had no detectable extrathoracic metastasis, and who were able to attend chest clinics monthly were admitted to the study from January 1965 to January 1968. Twenty-seven patients were excluded from all the analyses.The 217 patients admitted up to December 1965 form the "early" intake, the remaining 509 the "late" intake. There were no significant differences between the series in either intake period in a number of pretreatment factors studied. At 24 months 46% of the busulphan, 44% of the cyclophosphamide, and 49% of the placebo series were alive in the early intake, as were 49%, 50%, and 50% respectively in the late intake. There were no important differences between the series in survival related to pretreatment condition, cause of death, time of detection of metastases, and condition of the survivors at 24 months. Maintenance chemotherapy was interrupted to a greater extent in the busulphan than in the cyclophosphamide series and least in the placebo series.In both intakes clinical toxicity was more frequent in the cyclophosphamide series and similar in frequency in the busulphan and placebo series. Haematological toxicity was particularly frequent and severe in the busulphan series, especially in the early intake, platelet depression being the predominant manifestation.It is concluded that there is no evidence that either of the two cytotoxic drugs in the dosage prescribed improved survival for the two-year period of observation, though a final evaluation of the adjuvant chemotherapy as studied in this investigation will have to await the results at five years.