Fatal pulmonary toxicity by the association of radiotherapy and medroxyprogesterone acetate.

This report describes a fatal pneumonitis occurring in a breast cancer patient while on adjuvant treatment with radiotherapy and medroxyprogesterone acetate. The clinical and radiologic features, as well as the timing of this pneumonitis, make a radiation pneumonitis more than probable. A radiation pneumonitis was also observed in other patients treated in the same way. Medroxyprogesterone acetate thus seems to act as a radiosensitizer since no such effects were seen in patients treated with radiotherapy alone. The radioenhancing effect is not limited to the lungs, since radioesofagitis was also encountered in similarly treated patients.