Background: Despite meticulous preoperative diagnostics, aborted hyperthermic intraperitoneal chemotherapy (AHIPEC) is a common, unsuccessful outcome of curative cytoreductive surgery (CRS)/HIPEC.
Objective: The aim of this study was to evaluate the association between AHIPEC and preoperative risk factors of patients with mucinous appendiceal cancer (AC).
Methods: A single-institute, case-control study was conducted using a prospective database. Potentially resectable patients with peritoneal carcinomatosis of mucinous AC origin with AHIPEC between October 1994 and February 2019 were identified. Preoperative risk factors were reviewed. Analysis was conducted by tumor grade: low-grade, high-grade, and signet ring cell carcinoma (high-S). All available tumor-type-matched successful CRS/HIPEC controls were obtained from the same database. Univariable and multivariable analyses were performed.
Results: Overall, 21, 44, and 15 AHIPEC cases and 153, 133, and 53 tumor-matched controls were identified for low-grade, high-grade, and high-S populations, respectively. Multivariable analysis revealed preoperative cancer antigen (CA) 19-9 > 1 upper limit of normal (ULN) [odds ratio (OR) 6.32; p = 0.014], CA125 > 2 ULN (OR 7.02; p = 0.039), C-reactive protein (CRP) > 2.5 mg/L (OR 13.7; p = 0.001), and previous HIPEC (OR 7.5; p = 0.031) were significantly associated with AHIPEC in the low-grade population. Preoperative CRP > 2.5 mg/L (OR 7.77; p < 0.0001) and previous HIPEC (OR 4.69; p = 0.004) were associated with AHIPEC in a multivariable model for high-grade AC. No single factor showed a significant association with AHIPEC in high-S patients.
Conclusion: Risk factors vary for AHIPEC among low-grade, high-grade, and high-S AC histology. Elevated preoperative CA19-9, CA125, CRP, and previous HIPEC should be considered in the selection process for CRS/HIPEC in low-grade AC, as well as elevated CRP and previous HIPEC in high-grade AC, to avoid unnecessary surgery.