Clinicopathological importance of colorectal medullary carcinoma

Purpose Medullary carcinoma (MC) is a rare tumor with a solid growth pattern without glandular differentiation and constitutes less than 1% of colorectal cancers. Lymph node positivity and distant organ metastasis were reported to be lower than in other poorly differentiated adenocarcinomas. Therefore, the diagnosis of MC is pathologically important in terms of follow-up and treatment. We aimed to investigate the characteristics of medullary cancer in our case series.