Presentation Patterns and Treatment Outcomes in Appendix Cancer Patients Traveling to a High-Volume Peritoneal Surface Malignancy Center

Abstract

Introduction

Mucinous appendix cancer (MAC) treatment is centralized at peritoneal surface malignancy centers (PSMCs), requiring patients to travel for cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC). We compared presentation patterns and outcomes for patients accessing a high-volume PSMC from in-state (I-S) vs out-of-state (O-S).

Methods

This cohort study of MAC patients with peritoneal metastases treated with CRS/HIPEC (1998-2023) used a prospective database. Travel distance, presentation (time from diagnosis [TFD], peritoneal cancer index [PCI], prior surgery score [PSS], and systemic chemotherapy [SCh]), quality (complete cytoreduction [CC-0/1] and grade III/IV Clavien-Dindo complications), and overall survival (OS) were compared between O-S and I-S patients. A hazard ratio (HR) with 95% confidence interval (CI) for 10-year OS was evaluated using Cox regression for O-S travel, adjusting for age, histology, PCI, and prior treatment.

Results

Overall, 369 patients were included: 223 (60.4%) O-S and 146 (39.6%) I-S, with median travel distances of 180 [IQR: 83-729] and 29 [IQR: 14-59] miles, respectively. Compared to I-S, O-S had longer TFD (median: 4.6 vs 2.8 months, P < 0.001), higher PCI (median: 32 vs 24, P = 0.001), and higher rates of PSS-2/3 (40.4% vs 28.6%, P = 0.023) and SCh (31.8% vs 19.2%, P = 0.007). CC-0/1 (84.8% vs 91.4%, P = 0.063) and major complication (15.2% vs 21.4%, P = 0.132) rates were comparable. O-S travel did not affect OS (HR: 1.08 [95% CI: 0.73, 1.61]).

Conclusion

Traveling to a PSMC is associated with delayed presentation, more advanced disease, and prior treatments. However, quality and survival outcomes remain unaffected. Early referral and support for travel are essential.

Graphical Abstract