Thirty-Year-Old Male Patient with Non-Seminoma and Coincidental Rectal Cancer.

We present the case of a 31-year-old male patient with non-seminoma (90% embryonal carcinoma, 10% teratoma) pT1b L1 V0 Pn0 R0 cN2 cM0, Clinical Stage IIb and "good prognosis group" according to IGCCCG of the left testis. According to EAU guidelines, he received three cycles of BEP. After the second cycle, he developed recurrent, clinically not significant rectal bleeding, which we associated with deep thrombocytopenia. Following chemotherapy, there was one lymph node in the CT scan left, with a diameter of 0.9 cm at the inferior mesenteric arteria and the rectal bleeding did not stop; so coloscopy and staging revealed rectal cancer (adenocarcinoma) with peritoneal carcinosis. The patient was scheduled for radio-chemotherapy. Next-generation sequencing of the adenocarcinoma showed two mutations in KRAS and TP53 genes. To our knowledge, this is the first case of non-seminoma and coincidental rectal cancer. Furthermore, this case underlines the significance of molecular biological studies for the development of individualized targeted therapies, especially in younger patients and in chemo- and/or platin-resistance.