Long-term survival after multimodality treatment of metastatic mixed adenoneuroendocrine carcinoma of colon: A case report.

BACKGROUND

Mixed adenoneuroendocrine carcinoma (MANEC) is a rare malignancy that can be effectively treated with surgery in its early stages. However, there is currently no established treatment protocol for metastatic cases.

CASE SUMMARY: We present a case of a patient diagnosed with liver metastasis (LM) from ascending colon MANEC. The patient is a 40-year-old male who was diagnosed to have ascending colon MANEC with LM in March 2014. Following surgical resection of both the primary tumor and the LM, the patient received first-line chemotherapy with the mFOLFOX6 regimen. After six months of the initial treatment, the patient experienced multiple recurrences of LM. These LM were successfully treated by a multidisciplinary approach including chemotherapy, surgical resection, and radiofrequency ablation (RFA). Remarkably, in June 2017, the patient achieved a complete response, which has been maintained to date, resulting in overall long-term survival of ten years. Advanced colorectal MANEC is often associated with LM, and multiple intrahepatic recurrences may be characteristic of this disease.

CONCLUSION

The use of local treatment modalities, such as surgery and RFA, in conjunction with chemotherapy, has demonstrated promising efficacy and warrants further investigation.