ORIGINAL RESEARCH

Microsatellite instability in colorectal neuroendocrine neoplasms

Meshcheryakova MYu, Kolesnikov EN, Trifanov VS, Timoshkina NN, Snezhko AV, Gvaldin DYu
About authors

National Medical Research Center of Oncology, Rostov-on-Don, Russia

Correspondence should be addressed: Milana Yu. Mesheryakova
14 liniya, 63, Rostov-on-Don; ur.liam@analimavokayrehsem

About paper

Author contributions: Kolesnikov EN — data collection, analysis and interpretation; manuscript editing; Trifanov VS — study design; data collection, manuscript editing; Timoshkina NN — data analysis and interpretation; manuscript preparation; Snezhko AV — data acquisition; Gvaldin DYu — data analysis and interpretation; Meshcheryakova MYu — literature analysis; manuscript preparation.

Compliance with ethical standards: the study was approved by the Ethics Committee of the National Medical Research Centre for Oncology (Protocol № 3 dated February 9, 2021); informed consent was obtained from all study participants.

Received: 2022-01-12 Accepted: 2022-01-27 Published online: 2022-02-14
|

Microsatellite instability (MSI) characterizes a special molecular genetic subtype of malignancies and is associated with the deficiency of mismatched DNA repair. There are no reliable data on the frequency of MSI in colorectal neuroendocrine neoplasms due to the relative rarity of this cancer type. The prognostic significance of MSI is debatable. The aim of this study was to investigate the frequency of the MSI phenotype among colorectal neuroendocrine neoplasms (NENs) with different primary location, grade and stage. Twenty-nine patients (15 men and 14 women, mean age: 62.5 years) included in the study underwent surgery for colorectal neuroendocrine tumors between 2015 and 2018. The mean follow-up period was 3.8 years.  Colorectal NENs were grouped by primary location and stage. The majority of the patients (52%) had stage III cancer at diagnosis. The microsatellite stability (MSS) phenotype was confirmed in 24 patients (83%), whereas the MSI phenotype was observed in 5 patients (17%). All MSI-positive tumors were stage I well-differentiated grade G1 or G2 neuroendocrine tumors (NETs) of the rectum. Overall survival was 50% for patients with stage II MSS-positive NENs of the colon and rectum, 33% for stage III and 0% for stage IV. For patients with stage I MSI-positive NENs of the rectum, overall survival was 100%. Thus, the frequency of MSI-positive colorectal NENs was estimated.

Keywords: prognosis, colorectal neuroendocrine neoplasms, microsatellite instability, overall survival

КОММЕНТАРИИ (0)