When a thymic carcinoma "becomes" a GIST.

Thymic carcinoma (TC) is a rare intrathoracic malignancy that it can be invasive and refractory to conventional treatment. Comprehensive genomic analysis evidenced a molecularly distinct subset of thymic carcinoma with high prevalence of c-kit mutation, which may behave as a gastrointestinal stromal tumor (GIST). Here, we present a case report of TC with c-Kit mutation, who has relapsed after exposure to multiple lines of combination chemotherapy, but he has shown an impressive and long lasting response to sunitinib after imatinib failure.