Outcomes of Primary Colorectal Sarcoma: A National Cancer Data Base (NCDB) Review

Introduction: Primary colorectal sarcomas are a rare entity with anecdotally poor outcomes. We sought to inform surgeons, oncologists, and researchers of the characteristics and outcomes of these understudied and difficult-to-manage tumors. Methods: The National Cancer Data Base (NCDB) was queried for patients with pathologically confirmed primary sarcoma of the colon or rectum (1998–2012). Gastrointestinal stromal tumors were excluded. Unadjusted overall survival was reported using the Kaplan-Meier method. Patients with colorectal adenocarcinoma were used as a comparison cohort. Results: Four hundred thirty-three patients with primary colorectal sarcoma were identified (57.5% leiomyosarcoma subtype). Median age was 63 [inter-quartile range 52, 75] years with 23.1% between the ages of 18 and 50 and 48.7% female. Majority of sarcomas were located in the colon (70.7%). When compared to 696,902 patients with adenocarcinoma, sarcoma patients were younger, had larger tumors, were more likely node negative and rectal in location, and higher grade (all p < 0.001), while sex, race, and comorbidity score were similar (all p > 0.05). Overall survival was lower at 5 years in patients with sarcoma (43.8%) than adenocarcinoma (52.3%, p < 0.001). Conclusion: Primary colorectal sarcomas are rare and present at a younger age and higher grade than adenocarcinoma of the colon and rectum. Survival is significantly worse compared to adenocarcinoma patients.