Ovarian metastases of pancreatic adenocarcinoma: clinical presentation, role of surgery, and potential value of the mutational profile for the differential diagnosis with primary mucinous ovarian carcinoma

Background: Ovarian metastases (OM) of pancreatic adenocarcinoma (PA) (OM-PA) can mimic primary ovarian mucinous carcinoma (POMC) on imaging and histology. These metastases are often symptomatic and not highly chemosensitive, so that oophorectomy may be considered. Aims: The aims of this study were to compare the characteristics of OM-PA and POMC, and discuss the role of surgery. Patients and Methods: Clinical, imaging, and histological data of patients with OM-PA and POMC (2000-2017) in three tertiary centers were reviewed. Twenty-six genes were analyzed by next generation sequencing (NGS) on both primary PA and OM-PA. Results: Twenty-two women with OM-PA (n = 13, 11 with surgical resection) or POMC (n = 9) were selected. OM-PA were smaller than POMC (p = 0.02); imaging, histological, and immunohistochemistry data did not clearly differentiate OM-PA from POMC in 12 of 22 cases (54%). Seven PA/OM-PA pairs were analyzed, and a concordant KRAS mutation was identified in all cases. In four OM-PA, concordant mutations were also found in TP53 (n = 3), SMAD4 (n = 1), MET (n = 1), and PDGFRA (n = 1) genes. The aim of oophorectomy in 11 OM-PA was for antalgic (n = 6) or curative (n = 5) intent. Pain improved in 4/6 of the former patients, but 2/6 had significant morbidity, and 2/6 died of rapid tumor progression. After oophorectomy, median progression-free and overall survivals were 6 (0-11) and 8 months (1-131), respectively. Conclusion: Analysis of mutation profiles in both primary PA and ovarian tumors, especially KRAS, can help to determine the pancreatic origin of OM-PA. Surgical resection of OM-AP in highly selected patients may improve pelvic symptoms but may also cause significant morbidity. The benefit to survival requires further studies.