Colorectal carcinoma (CRC) is one of the major causes of cancer mortality worldwide.[1] Colorectal signet ring cell carcinoma (SRCC) is a rare subtype of CRC, manifesting at a low rate of about than 1%.[2] The term of SRCC is a descriptive term, denoted by the histologic observation of cell nuclei being pushed to the periphery due to excess intracytoplasmic mucin.[3–5] SRCC was firstly reported in 1951 by Laufman and Saphir.[6] The majority of SRCC cases are found in stomach, although some cases have also been reported in breast, lung, bladder, pancreas, and colon-rectum. Here, MUC5AC is linked to colorectal carcinoma.