Near complete remission of an inoperable pancreatic acinar cell carcinoma after BRAF-/MEK-inhibitor treatment—A case report and review of the literature

Introduction: Pancreatic acinar cell carcinomas are rare malignant neoplasms. High-quality evidence about the best treatment strategy is lacking. We present the case of a 52-year-old male with a BRAF^V600E-mutated PACC who experienced a complete remission after chemotherapy with BRAF-/MEK-inhibitors. Case: The patient presented with upper abdomen pain, night sweat, and weight loss. CT scan showed a pancreatic tumor extending from the pancreas head to body. Histological workup identified an acinar cell carcinoma. As the tumor was inoperable, chemotherapy with FOFIRNIOX was initiated and initially showed a slight regression of disease. The regimen had to be discontinued due to severe side effects. Molecular analysis identified a BRAF^V600E mutation, so the patient was started on BRAF- and MEK-inhibitors (dabrafenib/trametinib). After 16 months, CT scans showed a near complete remission with a markedly improved overall health. Discussion: Studies suggest that up to one-fourth of PACCs carry a BRAF mutation and might therefore be susceptible to a BRAF-/MEK-inhibitor therapy. This offers a new therapeutic pathway to treat this rare but malignant neoplasm.