[A man with colorectal signet ring cell carcinoma: which therapy is required?]

Primary colorectal signet ring cell carcinoma (SRCC) is rare and often affects younger patients. It demonstrates a different biological behaviour and has a less favourable prognosis than the more conventional colorectal adenocarcinoma.

Patient A, a 65-year-old man, presented with a change in bowel habit. Colonoscopy showed a stenosis with signs of a nonspecific inflammation. However, laparoscopy revealed a primary colorectal SRCC with diffuse peritoneal metastases. Standard chemotherapy was unsuccessful. Patient A died 13 months after diagnosis.

Based on clinical and molecular differences, SRCC can be recognized as a separate subtype of colorectal cancer. The case description illustrates that this group of patients may benefit from a different management strategy than the usual therapy. A greater understanding of the characteristics of this specific malignancy is needed.