Signet-Ring Cell Colorectal Cancer and Signet-Ring Cell Component Colorectal Cancer: Do They Differ in Clinical Behavior?

Background: Signet-ring cell colorectal cancer (SRCC) and colorectal cancer with a signet-ring cell component (SRC) are rare histological subtypes associated with poor prognosis. Although these entities are classified separately based on pathological criteria, it remains unclear whether they differ in clinical behavior and survival outcomes. This study aimed to compare the clinicopathological characteristics and survival of patients with SRCC and SRC. Methods: Patients who underwent surgery for colorectal cancer (CRC) between January 2012 and December 2019 and were diagnosed with SRCC or SRC on histopathological examination were retrospectively included. Demographic, clinical, and survival data were analyzed and compared between the two groups. Results: A total of 32 patients (22 males, 10 females) with SRCC or SRC were included, representing 2.6% (32/1253) of all CRC cases operated at our center. Seven patients (five with SRCC and two with SRC) had synchronous distant metastases, including liver-only metastases (9%), diffuse intra-abdominal seeding (9%), and ovarian metastasis (3%). The mean disease-free survival was 19.2 ± 3.3 months overall, and 17.18 ± 3.61 months for SRCC and 19.3 ± 9 months for SRC. The mean overall survival was 70.9 ± 10.18 months overall, and 65.95 ± 13.77 months for SRCC and 79.20 ± 15.03 months for SRC. No statistically significant difference in overall survival was observed between the groups (p = 0.534). Conclusions: SRCC and SRC demonstrate broadly similar clinicopathological features, with younger age at diagnosis observed in SRCC patients. However, given the limited sample size, the absence of statistically significant differences in survival outcomes should be interpreted with caution and does not imply equivalence. Distant metastasis remains the most important prognostic factor in both groups.