Exacerbation of radiation fibrosis with erlotinib: another pattern of radiation recall phenomenon.

A 79-year-old woman with advanced lung cancer presented with worsened radiation fibrosis after administration of erlotinib. After radiation therapy 7 months previously, she had radiation fibrosis that had been stable for months. On the 19th day after administration of erlotinib, low-grade fever and mild dyspnea developed accompanied by new pulmonary opacity in the area of the radiation fibrosis, which improved without therapy. We surmise that this is a manifestation of the radiation recall phenomenon, and discontinuation of the drug should be considered with discretion.