Primary Colorectal Signet-Ring Cell Carcinoma with Synchronous Colonic Metastases in an Asymptomatic Patient: Case...

Less than 1% of all colorectal cancers (CRCs) are primary colorectal signet-ring cell carcinomas (SRCCs), which represent an uncommon and aggressive histological subtype. Given their subtle onset and rapid progression, these are often diagnosed in an advanced stage, and can be distinguished by the presence of mucin-producing signet-ring cells. Synchronous colonic metastases at initial diagnosis are rather uncommon.

We report the case of a 65-year-old male patient who underwent a routine colonoscopy following a positive fecal immunochemical test (FIT). The patient had no remarkable medical history and was asymptomatic. A 3 cm semi-pedunculated polyp and several smaller depressed lesions, 2 cm maximum in diameter, were observed in the descending colon during the colonoscopy. Multiple biopsies were obtained. The lesions were found to be SRCC according to histopathological examination. There was no sign of extra-colonic metastases on the computed tomography (CT). The patient was referred for extensive hemicolectomy, regional lymphadenectomy, and adjuvant chemotherapy.

This article provides a thorough literature review on this uncommon presentation and discussion regarding the current understanding of the pathogenesis, clinical manifestations, and management strategies of SRCC. This case highlights the importance of routine screening in detecting aggressive malignancies like SRCC in asymptomatic individuals. Early identification through colonoscopy can lead to timely intervention, potentially improving prognosis.