Summary

Background:

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) are established treatments for peritoneal metastasis from colorectal cancer (PM-CRC). The peritoneal carcinomatosis index (PCI) measures disease burden.

Objectives:

To evaluate the effect of PCI on short- and long-term outcomes of patients with PM-CRC who underwent CRS-HIPEC.

Methods:

We retrospectively analyzed 120 PM-CRC patients who underwent CRS-HIPEC, categorizing them into four PCI groups (PCI ≤ 3, PCI 4–6, PCI 7–11, PCI >11). We evaluated perioperative outcomes and long-term survival.

Results:

Higher PCI scores were associated with increased surgical complexity, longer operative times, more organ resections, and higher blood transfusion requirements. Complete cytoreduction was achieved in 100% of the PCI ≤ 3 group, but only in 70.8% of the PCI > 11 group (P = 0.001). Postoperative outcomes showed a trend toward less major morbidity in low PCI patients (16.7% vs. 28%) and significantly shorter hospital stays (10–13 days vs. 19 days, P = 0.006). The 90-day mortality rate was 0% in the PCI ≤ 3 group compared to 11.5% in the PCI > 11 group. Long-term outcomes revealed significantly better disease-free survival (DFS) and overall survival (OS) for the PCI ≤ 3 group (DFS: 22 months vs. 4–6 months; OS: 79.6 months vs. 21–40 months, P < 0.001).

Conclusions:

Patients with low PCI scores experience reduced morbidity and improved long-term survival, supporting the use of CRS-HIPEC in this subgroup. Further research is needed to enhance treatment strategies for patients with high PCI scores.