Small Bowel Neuroendocrine Neoplasms: A Single Tertiary Center Real World Experience

Small bowel neuroendocrine neoplasms (SB-NENs) are a rare type of tumor that is clinically challenging and is often diagnosed in advanced stages. This retrospective study aimed to characterize the clinical presentation, diagnostic workup, and therapeutic strategies, as well as to evaluate the prognosis of patients managed in a tertiary care center in Bucharest, Romania, over five years.

We conducted an observational, retrospective cohort study on 42 cases of SB-NEN evaluated at our center between January 1, 2020, and March 31, 2025. Data regarding clinicopathological characteristics, treatments, and disease evolution were summarized. Overall survival was estimated at 1, 3, and 5 years.

Computed tomography was the most frequently used imaging method for diagnosis (52.4%). Surgery was the most adopted method for obtaining the pathological specimen, used in 70.7% of cases. The majority of tumors were well-differentiated (85.6%). The overall survival distribution showed a median survival time of 94 months. The cumulative proportion of patients surviving at 1 year was 97.6%, at 3 years was 89.3% and at 5 years was 75.7%. There was a significant difference in overall survival stratified by tumor grading (p=0.006), indicating that this was a significant prognostic factor; the metastatic status and large tumors showed a trend toward statistical significance, but they did not meet the conventional threshold (p=0.068 and 0.103, respectively).

SB-NEN showed favorable outcomes, with surgery improving survival even in some metastatic cases. Lower tumor grade was associated with a better prognosis, while somatostatin analogues (SSA) therapy showed no survival benefit. Patients with large tumors and metastatic disease also showed a trend towards reduced survival.