Clinical Benefit of Sorafenib Combined with Paclitaxel and Carboplatin to a Patient with Metastatic Chemotherapy‐Refractory Testicular Tumors

Testicular cancer is one of the few tumor types that have not yet benefited from targeted therapy. Still no new active agents for treating this cancer have been identified over the past 15 years. Once patients are refractory to cisplatin‐based chemotherapy, they will be expected to die from testicular cancer. This report describes a 21‐year‐old man who was refractory to chemotherapy and immunotherapy. Whole exome sequencing and low‐depth whole genome sequencing confirmed the KRAS gene amplification, which may lead to the tumor cells’ progression and proliferation. After discussion at the molecular tumor board, the patient was offered paclitaxel, carboplatin, and sorafenib (CPS) based on a phase III clinical trial of melanoma with KRAS gene copy gains. After treatment with CPS, the patient achieved excellent curative effects. Because of a nearly 50% frequency of KRAS amplification in chemotherapy‐refractory testicular germ cells, CPS regimen may provide a new therapy, but it still warrants further validation in clinical studies. KEY POINTS. Chemotherapy‐refractory testicular cancer has a very poor prognosis resulting in a lack of effective targeted therapies. KRAS gene amplification occurs in nearly 20% of testicular cancer and 50% of chemotherapy‐refractory testicular cancer. KRAS amplification may activate the MAPK signaling pathway, and inhibition of MAPK by sorafenib combined with paclitaxel and carboplatin could be a viable option based on a phase III clinical trial of melanoma. To the authors’ knowledge, this is the first report of response to sorafenib‐based combination targeted therapy in a patient with chemotherapy‐refractory testicular cancer. Clinical genomic profiling can confirm copy number variation of testicular cancer and provide insights on therapeutic options.