Clinical features and the efficacy of adjuvant chemotherapy in resectable small bowel adenocarcinoma: a single-center, long-term analysis

BACKGROUND: Small bowel adenocarcinoma (SBA) is a rare gastrointestinal malignancy. There is no standard regimen for adjuvant chemotherapy for treating SBA. This study aimed to assess the efficacy of adjuvant chemotherapy in patients with resectable SBA. METHODS: This retrospective study collected data from 148 eligible SBA patients who received radical resection at a single institution. The patients’ clinicopathological characteristics were reviewed and disease-free survival (DFS) time and overall survival time (OS) were estimated by the Kaplan-Meier method. RESULTS: The patients had a median age of 57 years at the time of diagnosis. In most cases, the primary tumor was located in the duodenum (75.68%). Of the 55 patients who received adjuvant chemotherapy, 43 received the combined regimen and 12 received single agent chemotherapy. During the follow-up period, 87 patients (58.87%) relapsed. The median DFS and the median OS were 19 and 32 months for all patients, respectively. Stage, N-stage, adjuvant chemotherapy, and having more than one symptom at the time of diagnosis were factors associated with DFS and OS. The 43 patients who received combined adjuvant chemotherapy generally exhibited better DFS and OS at 3 and 5 years (DFS: 75.7% and 57.3%, respectively; OS: 75.7% and 62.5%, respectively) than the patients who did not receive the same treatment. The survival time was significantly improved in patients with initial CA19-9 of less than 300 µ/mL or CEA of less than 10 ng/mL. Multivariate analysis revealed N stage and combined adjuvant chemotherapy were independent factors for DFS. However, only combined adjuvant chemotherapy could prolong OS for patients who underwent radical resection. CONCLUSIONS: In our study, both N stage and combined adjuvant chemotherapy are found to influence postoperative recurrence of SBA. Moreover, combined adjuvant chemotherapy is an independent prognostic factor of DFS and OS.