Malignant melanoma: sex differences in response to chemotherapy?

From studying cell kinetic parameters it is demonstrated that both males and females with metastatic melanoma respond favourably to various chemotherapy schedules. Male patients have a shorter doubling time (DT) of pulmonary secondaries prior to chemotherapy compared to females, which seems to give them a less favorable starting point. Also, the DT of lung metastases of males after chemotherapy is less favourable than that of females. However, a significant difference in DT is noticed between measurements prior to and after the institution of chemotherapy in both sexes. It is concluded that the alleged sex differences in response to chemotherapy may be an artifact due to differences in tumor growth kinetics between males and females.