Medullary colonic carcinoma with microsatellite instability has lower survival compared with conventional colonic adenocarcinoma with microsatellite instability

• Main Authors: Miguel A. Gómez-Álvarez, Leonardo S. Lino-Silva, Rosa A. Salcedo-Hernández, Alejandro Padilla-Rosciano, Erika B. Ruiz-García, Horacio N. López-Basave, German Calderillo-Ruiz, José M. Aguilar-Romero, Jorge A. Domínguez-Rodríguez, Ángel Herrera-Gómez, Abelardo Meneses-García
• Format: Article
• Language: English
• Published: Termedia Publishing House 2016-12-01
• Series: Gastroenterology Review
• Subjects: colorectal; cancer; microsatellite instability; medullary carcinoma; survival
• Online Access: https://www.termedia.pl/Medullary-colonic-carcinoma-with-microsatellite-instability-has-lower-survival-compared-with-conventional-colonic-adenocarcinoma-with-microsatellite-instability,41,28944,1,1.html

Introduction: Colorectal medullary carcinoma (MC) is a rare subtype of poorly differentiated adenocarcinoma (PDA) with unclear prognostic significance. Microsatellite instable (MSI) colorectal carcinomas have demonstrated better prognosis in clinical stage II. Aim: To analyze the survival and clinicopathological characteristics of MCs versus PDAs with MSI in clinical stage III. Material and methods: We studied 22 cases of PDAs with MSI versus 10 MCs. Results : Of the 10 MCs, 7 patients were men; the mean age was 57.8 ±5.6 years. The mean tumor size was 9.6 ±4.1 cm, and the primary site was the right colon in 9; 7 patients showed lymph node metastases (LNM) and lymphovascular invasion (LVI). Of the 22 PDA cases, 12 (54.5%) were women with a mean age of 75 ±16.1 years. The mean tumor size was 6.4 ±3.2 cm. Twelve (54.5%) presented in the right colon, 21 (95.5%) showed LNM and 7 (31.8%) LVI. Follow-up was 32 ±8 months, with a 5-year overall survival of 42.9% for MCs and 76.6% for PDAs (p = 0.048). Univariate analysis found local recurrence (p = 0.001) and medullary subtype (p = 0.043) associated with lower survival. Conclusions : Medullary carcinomas were of greater tumor size and associated with more LVI and worse survival versus PDAs with MSI in stage III.