Successful treatment of GEMOX regimen combined with nimotuzumab in the pancreatic cancer with wild KRAS and mutant BRCA: a report of two cases.

Background: Pancreatic cancer is characterized by chemoresistance. In recent years, more potential therapeutic molecular targets for pancreatic cancer have been developed, and thus increasing attention has been paid to precise chemotherapy to improve the prognosis of patients with advanced pancreatic cancer.

Case description: In this study, we reported two rare cases of advanced pancreatic cancer. One patient was diagnosed with retroperitoneal lymph node metastasis after radical resection of pancreatic ductal adenocarcinoma. The diagnosis of another patient was pancreatic ductal adenocarcinoma with liver metastasis. The whole genome sequencing of their tumor tissues detected both wild-type Kirsten rat sarcoma viral oncogene homolog (KRAS) and mutant breast cancer susceptibility gene (BRCA). And immunohistochemistry showed their tumor tissue was negative for epidermal growth factor receptor. We used the combined chemotherapy of gemcitabine (1,000 mg/m²) + oxaliplatin (135 mg/m²) + nimotuzumab (400 mg). After nine times of chemotherapy, the imaging examinations including positron emission tomography-computed tomography showed that both cases achieved complete remission. And there were no serious side effects during chemotherapy. Then, the patients were treated with oral olaparide (600 mg/day) for one year, and survived without tumor progress for more than 1.5 years.

Conclusions: These two cases achieved excellent effects of precise chemotherapy, which provided an important reference for the treatment of pancreatic cancer patients with wild KRAS and mutant BRCA.