Introduction SRCC is an aggressive variant affecting younger population and has poorer prognosis. The literature explaining the biology as well as the optimum treatment algorithm of this particular variant is scarce due to its low incidence. Here, we present our experience about this peculiar variant from a tertiary cancer centre from India (Tata Memorial Centre, Mumbai).
Method It’s a retrospective study (2011–2014) of all patients diagnosed with SRCC with department of gastro-intestinal oncology. SRCC was defined as per WHO criteria (adenocarcinoma with more than 50% of signet-ring cells). Peritoneal metastases or recurrences constituted peritoneal deposits, malignant ascites, omental deposits, ovarian deposits. SPSS-20 was used for statistical calculation.
Results 170 consecutive patients with SRCC were diagnosed. It constituted 11.4% of all colorectal cases (170/1487). Median Age of the cohort was 41 years. Male to female ratio was 1.8:1. Most common location was recto-sigmoid area (Rectum: 41.2% and Sigmoid: 13.5%). Majority patients presented in stage III (51.8%) and stage IV (39.4%). Most of the stage IV patients had isolated peritoneal metastases (58/67, 86.5%). Colonic tumours, as compared to rectal tumours had higher incidence of peritoneal metastases (83.3% v/s 91.4%, p = 0.074) as well as isolated peritoneal recurrences (20.5% v/s 37.5%, p = 0.062). Most patients had high nodal burden (pN2: 57.9%). Curative therapy was feasible only in 56.47% (79/170) patients. 36.7% patients recurred after curative surgery. Amongst them 65.5% patients had isolated peritoneal recurrences. Amongst rectal cases, pathological complete response after NACTRT was seen in 21.6% (8/37) patients. Circumferential resection margin (CRM) was involved in 17.9% (7/39) patients. Median follow up was 17.4 months. Median relapse free survival (RFS) and overall survival (OS) of the cohort were 14.9 and 18.13 months respectively. OS of peritoneal and non-peritoneal metastases were equivalent (16 v/s 13months; p = 0.729). CRM involvement was associated with poorer RFS (15 months v/s 37.2 months; p = 0.060) and OS (19.9 months v/s 41.5 months; p = 0.018). Colonic primaries were associated with poorer OS than rectal tumours after curative resection (32.298 months v/s 40.089 months, p = 0.058) and RFS (24.74 months v/s 34.02 months; p = 0.048).
Conclusion SRCC affects young patients and has predilection for peritoneal dissemination. More aggressive and/or extended chemotherapy schedules as well as prophylactic HIPEC at the time of primary surgery, especially for colonic tumours, should be attempted in a randomised control trial setting in order to improve dismal survival in these patients.
Disclosure of interest None Declared.