Mixed Neuroendocrine Non-Neuroendocrine Tumor (MINEN) of the Liver: Report of Two Cases and Review of the Literature

Objective: To highlight two cases mixed neuroendocrine non-neuroendocrine tumors (MINEN) of the liver and to review the literature till date. To present two cases of MINEN of the liver diagnosed in our centre with clinical & diagnostic workup, the treatment modalities, and follow up. Extensive review of the literature and compilation of the presentation and treatment modalities used in those cases. Case Reports: Thirty-three cases of MINEN of the liver have been reported till date including ours. Our cases presented as incidental masses in liver during workup for other symptoms. AFP levels were normal in both cases but PIVKA (Protein induced by vitamin K absence) levels were increased. Resection was done in one of the cases while the other patient had to undergo transplantation. A diagnosis of MINEN was made on H&E, and confirmed on IHC. One patient was unfit for systemic chemotherapy whereas the other patient received cisplastin and etoposide based chemotherapy. Both patients developed metastasis on follow up but are still alive after 12-15 months. Conclusion: MINEN is an uncommon tumor of the liver with a poor prognosis as shown by the few studies available. Recurrence and distant metastases are often described even after complete resection and the course is fatal. The role of adjuvant chemotherapy following surgical resection is not fully elucidated. Mean survival in the cases reported ranged from 1 month to 33 months. However, no significant differences were seen in the clinicopathologic profile of the cases described so far. Further multiinstitutional studies and follow up will help to further characterize this subtype for appropriate treatment.