Neuroendocrine carcinomas of the digestive tract are rare and aggressive tumours. In localised disease, the treatment is surgery. Based on expert consensus, international guidelines recommend the administration of adjuvant chemotherapy combining etoposide and platinum derivatives, justified by the high risk of metastatic relapse. However, no clinical study has proven the benefit of neoadjuvant or adjuvant chemotherapy.

We aimed to evaluate their effect in this indication.

We performed a retrospective observational French study to evaluate overall and disease-free survivals, prognostic factors for survival and chemotherapy toxicity.

Seventy-three patients had surgical resection of a localised digestive neuroendocrine carcinoma between 2000 and 2016. The majority of patients presented colorectal (35%) tumours and median Ki-67 value was 70%. Forty-three patients received chemotherapy, either perioperative (neoadjuvant ± adjuvant) or adjuvant. Median overall and disease-free survivals for the whole population were 24 and 9 months, respectively. Median overall and disease-free survivals for patients receiving chemotherapy were 62 and 13 months, respectively. Positive postoperative node status and Ki-67≥ 80% had a negative prognostic impact on overall and disease-free survivals. Administration of chemotherapy had a positive prognostic impact on overall and disease-free survivals. Sixteen grade 3/4 toxicities were reported without toxic death.

Our results suggest a positive effect on survival of chemotherapy in resected digestive neuroendocrine carcinomas, but further studies are needed to confirm these results.