A case report of a dramatic response to olaparib in a patient with metastatic pancreatic cancer harboring a germline BRCA2 mutation

RATIONALE: Pancreatic cancer (PC) is considered as one of the deadliest cancers all over the world. Germline and somatic BRCA1/2 mutations have been widely studied in breast and ovarian carcinomas as they have been found to enhance the risk for disease progression. Olaparib, an oral poly(adenosine diphosphate-ribose)polymerase (PARP) inhibitor, has been approved for the treatment strategy of ovarian cancer with any BRCA1/2 mutations. There is a lack of studies which focus on the treatment of other cancer with BRCA-Mutation. PATIENT CONCERNS: This report describes a patient whose presenting complaints were “Physical examination showed that the pancreas was occupied for one month.” He initially was diagnosed with stage IV PC based on conventional imaging and pathologic assessment. He had a known germline BRCA 2 mutation, which exhibited a good response to PARP inhibitor therapy. DIAGNOSIS: Through the biopsy histopathological examination, imaging examination, and genetic testing, the patient was diagnosed as metastatic PC with BRCA2 mutation. INTERVENTIONS: He received gemcitabine and albumin-bound paclitaxel chemotherapy from March 15, 2017 to June 30, 2017, and Nivolumab immunotherapy as the maintenance therapy. After serum CA-199 level increased, Olaparib was orally administered from August 17, 2017 to March. After tumor relapsed, he received multiple lines of chemotherapy, including Trametinib Oxaliplatin, S-1, bevacizumab, and irinotecan liposome injection till July 17, 2018. OUTCOMES: We observed the patient had a good progression-free survival (7.4 months); the lesion of the pancreas was classified as partial disease through Olaparib treatment, which indicated significant shrinkage. But it is difficult to conclude whether such therapy could help prolong the overall survival for such patients. LESSONS: The targeted therapy Olaparib showed early signs of potential in treating PC in patients with mutations of the BRCA genes. With emerging therapeutic modalities and next-generation sequencing development, it is increasingly relevant to consider mutation screenings of patients with PC.