Cis/Etop chemotherapy as a ray of hope in mixed adeno-neuroendocrine carcinoma of colon

Background: Mixed adeno-neuroendocrine carcinoma (MANEC) is a rare pathological diagnosis reported by the World Health Organization in 2010 for the first time. Neuroendocrine tumors are characterized by rapid progression. Case Presentation: A 70-year-old man who complained about anemia, diarrhea and significant weight loss did colonoscopy. Biopsy showed a poorly differentiated carcinoma. Biopsy upon surgical rectosigmoid resection revealed a mixed neuroendocrine-adenocarcinoma. Chemotherapy with fofox6 regimen was started but after eight months, tumor relapsed in anastomosis site of surgery involving para aortic lymph nodes and growth of tumor had led to gastrointestinal obstruction symptom. We did relieving surgery and changed chemotherapy regimen to cisplatin/etoposide regimen. He responded to the treatment well, and the mass almost disappeared. Conclusions: The optimal strategy for management of mixed endocrine tumor is variable as they present rare and atypical. Adjuvant chemotherapy play a critical role in the treatment and survival due to MANEC aggressive progression and recurrence. Our data derived from this case may be essential for the diagnosis, treatment, and management of MANEC patients’ symptoms.