Who Undergoes Cytoreductive Surgery and Perioperative Intraperitoneal Chemotherapy for Appendiceal Cancer? An Analysis of the National Cancer Database

Abstract Background We sought to identify patterns of care for patients with appendiceal cancer and identify clinical factors associated with patient selection for multimodality treatment, including cytoreductive surgery and perioperative intraperitoneal chemotherapy (CRS/PIC). Materials and methods National Cancer Database (NCDB) data from 2004 to 2014 of all diagnoses of appendiceal cancers were examined. We examined treatment modalities, as well as demographic, tumor-specific, and survival data. A multivariate logistic regression analysis was performed to determine the patient cohort most likely to receive CRS/PIC. Kaplan–Meier was used to estimate survival for all treatment groups. Significance was evaluated at P  ≤ 0.05. Results We analyzed data on 18,055 patients. Nine thousand nine hundred ninety-two (55.3%) were treated with surgery only, 5848 (32.4%) received surgery and systemic chemotherapy, 1393 (7.71%) received CRS/PIC, 520 (2.88%) received chemotherapy alone, and 302 (1.67%) received neither surgery nor chemotherapy. Significant predictors of receiving CRS/PIC included male sex (OR 1.33, 95% CI: 1.11-1.59), white race (OR 2.00, 95% CI 1.40-2.86), non-Hispanic ethnicity (OR 1.92, 95% CI 1.21-3.05), private insurance (OR 1.52, 95% CI 1.26-1.84), and well-differentiated tumors (OR 4.25, CI: 3.39-5.32) ( P versus 62.4%, P versus 65.4%, P Conclusions Patients were more likely to undergo CRS/PIC if they were male, white, privately insured, and with well-differentiated tumors. CRS/PIC was associated with improved survival in patients with mucinous and low-grade tumors.