Treatment of Peritoneal Surface Malignancies by Cytoreductive Surgery (CRS) and Hyperthermic Intraperitoneal Chemotherapy (HIPEC) in Spain: Results of the National Registry of the Spanish Group of Peritoneal Oncologic Surgery (REGECOP).

INTRODUCTION: Treatment of Peritoneal Surface Malignancies (PSM) with cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) has achieved results never seen before in these patients, which classically have a poor prognosis. The possibility of conducting clinical trials in these diseases is complicated, since some of them are rare, so the analysis of large databases provides very valuable scientific information. The aim of this study is to analyze the global results of the National Registry of the Spanish Group of Peritoneal Oncologic Surgery (REGECOP), whose objective is to register all patients scheduled for HIPEC nationwide. METHODS: This is a retrospective analysis of the data recorded in the REGECOP from 36 Spanish hospitals from 2001 to 2021. There were 4159 surgical interventions in 3980 patients. RESULTS: 66% are women and 34% are men with a median age of 59 years (range 17-86). 41.5% of the patients were treated for Peritoneal Metastases (PM) of colorectal cancer (CRC); 32.4% were women with ovarian cancer (OC) with PM; 12.8% were treated for pseudomyxoma peritonei (PMP); 6.2% had PM from gastric cancer (GC); 4.9% had PM of non-conventional origin; and, finally, 2.1% of cases were patients diagnosed with peritoneal mesothelioma. The median Peritoneal Cancer Index (PCI) was 9 (0-39), and complete cytoreduction was achieved in 81.7% of the procedures. Severe morbidity (Dindo-Clavien grade III-IV) was observed in 17.7% of surgeries, with 2.1% mortality. Median hospital stay was 11 days (0-259). Median overall survival (OS) was 41 months for CRC patients, 55 months for women with OC, was not reached in PMP patients, was 14 months for GC patients, and 66 months in mesothelioma patients. CONCLUSIONS: large databases provide extremely useful data. CRS with HIPEC in referral centers is a safe treatment with encouraging oncologic results in PSM.

Efficacy and Safety of Intraoperative Hyperthermic Intraperitoneal Chemotherapy for Locally Advanced Colon Cancer: A Phase 3 Randomized Clinical Trial.

Importance: Peritoneal metastasis in patients with locally advanced colon cancer (T4 stage) is estimated to recur at a rate of approximately 25% at 3 years from surgical resection and is associated with poor prognosis. There is controversy regarding the clinical benefit of prophylactic hyperthermic intraperitoneal chemotherapy (HIPEC) in these patients. Objective: To assess the efficacy and safety of intraoperative HIPEC in patients with locally advanced colon cancer. Design, Setting, and Participants: This open-label, phase 3 randomized clinical trial was conducted in 17 Spanish centers from November 15, 2015, to March 9, 2021. Enrolled patients were aged 18 to 75 years with locally advanced primary colon cancer diagnosed preoperatively (cT4N02M0). Interventions: Patients were randomly assigned 1:1 to receive cytoreduction plus HIPEC with mitomycin C (30 mg/m2 over 60 minutes; investigational group) or cytoreduction alone (comparator group), both followed by systemic adjuvant chemotherapy. Randomization of the intention-to-treat population was done via a web-based system, with stratification by treatment center and sex. Main Outcomes and Measures: The primary outcome was 3-year locoregional control (LC) rate, defined as the proportion of patients without peritoneal disease recurrence analyzed by intention to treat. Secondary end points were disease-free survival, overall survival, morbidity, and rate of toxic effects. Results: A total of 184 patients were recruited and randomized (investigational group, n = 89; comparator group, n = 95). The mean (SD) age was 61.5 (9.2) years, and 111 (60.3%) were male. Median duration of follow-up was 36 months (IQR, 27-36 months). Demographic and clinical characteristics were similar between groups. The 3-year LC rate was higher in the investigational group (97.6%) than in the comparator group (87.6%) (log-rank P = .03; hazard ratio [HR], 0.21; 95% CI, 0.05-0.95). No differences were observed in disease-free survival (investigational, 81.2%; comparator, 78.0%; log-rank P = .22; HR, 0.71; 95% CI, 0.41-1.22) or overall survival (investigational, 91.7%; comparator, 92.9%; log-rank P = .68; HR, 0.79; 95% CI, 0.26-2.37). The definitive subgroup with pT4 disease showed a pronounced benefit in 3-year LC rate after investigational treatment (investigational: 98.3%; comparator: 82.1%; log-rank P = .003; HR, 0.09; 95% CI, 0.01-0.70). No differences in morbidity or toxic effects between groups were observed. Conclusions and Relevance: In this randomized clinical trial, the addition of HIPEC to complete surgical resection for locally advanced colon cancer improved the 3-year LC rate compared with surgery alone. This approach should be considered for patients with locally advanced colorectal cancer. Trial Registration: ClinicalTrials.gov Identifier: NCT02614534.

Perioperative chemotherapy versus surgery alone for resectable colorectal liver metastases: an international multicentre propensity score matched analysis on long-term outcomes according to established prognostic risk scores.

BACKGROUND: There is still uncertainty regarding the role of perioperative chemotherapy (CTx) in patients with resectable colorectal liver metastases (CRLM), especially in those with a low-risk of recurrence. METHODS: Multicentre retrospective analysis of patients with CRLM undergoing liver resection between 2010-2015. Patients were divided into two groups according to whether they received perioperative CTx or not and were compared using propensity score matching (PSM) analysis. Then, they were stratified according to prognostic risk scores, including: Clinical Risk Score (CRS), Tumour Burden Score (TBS) and Genetic And Morphological Evaluation (GAME) score. RESULTS: The study included 967 patients with a median follow-up of 68 months. After PSM analysis, patients with perioperative CTx presented prolonged overall survival (OS) in comparison with the surgery alone group (82.8 vs 52.5 months, p = 0.017). On multivariable analysis perioperative CTx was an independent predictor of increased OS (HR 0.705, 95%CI 0.705-0.516, p = 0.029). The benefits of perioperative CTx on survival were confirmed in patients with CRS and TBS scores ≤2 (p = 0.022 and p = 0.020, respectively) and in patients with a GAME score ≤1 (p = 0.006). CONCLUSION: Perioperative CTx demonstrated an increase in OS in patients with CRLM. Patients with a low-risk of recurrence seem to benefit from systemic treatment.

The American Society of Peritoneal Surface Malignancies evaluation of HIPEC with Mitomycin C versus Oxaliplatin in 539 patients with colon cancer undergoing a complete cytoreductive surgery.

BACKGROUND: Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) are gaining acceptance as treatment for selected patients with colorectal cancer with peritoneal carcinomatosis (CRCPC). Tremendous variations exist in the HIPEC delivery. METHODS: The American Society of Peritoneal Surface Malignancies (ASPSM) examined the overall survival in patients with CRCPC who underwent a complete cytoreduction and HIPEC with Oxaliplatin vs. Mitomycin C (MMC), stratifying them by the Peritoneal Surface Disease Severity Score (PSDSS). RESULTS: Median overall survival (OS) of 539 patients with complete cytoreduction was 32.6 months, 32.7 months for the MMC group and 31.4 months for the Oxaliplatin group (P = 0.925). However, when stratified by PSDSS, median OS rates in PSDSS I/II patients were 54.3 months in those receiving MMC vs. 28.2 months in those receiving oxaliplatin (P = 0.012), whereas in PSDSS III/IV patients, median OS rates were 19.4 months in those receiving MMC vs. 30.4 months in those receiving Oxaliplatin (P = 0.427). CONCLUSION: These data suggest that MMC might be a better agent for HIPEC delivery than Oxaliplatin in patients with CRCPC, favorable histologies and low burden of disease (PSDSS I/II) undergoing complete cytoreduction. Prospective studies are warranted, which stratify patients by their PSDSS and randomize them to HIPEC with MMC vs. Oxaliplatin.