Document Type : Research/Original Article
Asian School of Peritoneal Surface Malignancy Treatment, Kyoto City, Kyoto Prefecture, Japan
Department of Regional Cancer Therapy, Peritoneal Surface Malignancy Treatment Center, Kishiwada Tokushukai Hospital, Kishiwada City, Osaka Prefecture, Japan
Department of Regional Cancer Therapy, Peritoneal Dissemination Center, Kusatsu General Hospital, Kusatsu City, Shiga Prefecture, Japan
Department of Surgery, Mizonokuchi Hospital, Teikyo University, School of Medicine, Kawasaki, Kanagawa, Japan
Comprehensive treatment (COMPT) consisting of cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) improves survival in selected patients with peritoneal metastasis (PM) from colorectal cancer (CRC). The aim of the present study was to clarify clinicopathologic parameters that are indications to perform COMPT in CRC-patients with CRC-PM.
Between 2006 and 2021, 447 patients were selected as eligible for COMPT among 906 CRC-patients with PM. Clinicopathologic parameters contributing to long-term survival and cure were analyzed.
Results: A log-rank test showed a significant survival difference for peritoneal cancer index (PCI) (≤12 vs. ≥13), completeness of cytoreduction (CCR) score (CCR-0 vs. CCR-1), small bowel (SB)-PCI (≤2 vs. ≥3), liver/lung metastasis (LLM) (negative vs. positive), histologic type (differentiated type vs. signet ring cell (SRC) subtype), number of involved peritoneal sectors (≤6 vs. ≥7), HIPEC (done vs. not done) and postoperative complication (grade 0, 1, or 2 vs. grade 3, 4, or 5).
Muti-variate analyses revealed that CCR score (CCR-0 vs. CCR-1), SB-PCI score (≤2 vs. ≥3), LLM (negative vs. positive), and HIPEC (performed vs. not done) were independent prognostic factors.
The incidence of postoperative grade 3, 4 or 5 complication was 19.0% (85/447) and the mortality rate was 2.0% (9/447).
One hundred and seventy patients fulfilled the following clinicopathologic factors,PCI ≤12, SB-PCI ≤2, number of involved peritoneal sectors ≤6, no LLM, differentiated histologic type and CCR-0. The MST of these patients was 5.5 years, and 5- and 10-year survival rates were 57.8% and 24.6%, respectively. Postoperative grade 3, 4, and 5 complications in these 170 patients occurred in 9 (5.3%), 15 (8.8%) and 1 (0.6%), respectively.
Cured patients were defined as those alive without recurrence more than 5 years after CRS. All of the cured patients underwent CCR-0 resection. The PCI and SB-PCI of these 23 patients were ≤12 and ≤2, respectively.