RAS Mutation Decreases Overall Survival After Optimal Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy of Colorectal Peritoneal Metastasis: A Modification Proposal of the Peritoneal Surface Disease Severity Score
- 275 Downloads
Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) are currently the most accepted treatment for peritoneal metastases from colorectal cancer. Restrictive selection criteria are essential to obtain the best survival benefits for this complex procedure. The most widespread score for patient selection, the peritoneal surface disease severity score (PSDSS), does not include current biological factors that are known to influence on prognosis. We investigated the impact of including RAS mutational status in the selection criteria for these patients.
We studied the risk factors for survival by multivariate analysis using a prospective database of consecutive patients with carcinomatosis from colorectal origin treated by CRS and HIPEC in our unit from 2009 to 2017. The risk factors obtained were validated in a multicentre, international cohort, including a total of 520 patients from 15 different reference units.
A total of 77 patients were selected for local análisis. Only RAS mutational status (HR: 2.024; p = 0.045) and PSDSS stage (HR: 2.90; p = 0.009) were shown to be independent factors for overall survival. Early PSDSS stages I and II associated to RAS mutations impaired their overall survival with no significant differences with PSDSS stage III overall survival (p > 0.05). These results were supported by the international multicentre validation.
By including RAS mutational status, we propose an updated RAS-PSDSS score that outperforms PSDSS alone providing a quick and feasible preoperative assessment of the expected overall survival for patients with carcinomatosis from colorectal origin undergone to CRS + HIPEC.
The authors thank Dr. Jesus Esquivel for the diffusion of our study proposal to the different groups belonging to ASPSM (American Society Peritoneal Surface Malignancies). They also thank Dr. Pera (Department of Surgery of Hospital del Mar, Barcelona, Spain) for the review of the paper and Dr. Merlo (University Hospital Reina Sofia Cordoba, Spain) and Dra. Sluiter (Department of Surgery, VU. University Medical Center, Amsterdam, The Netherlands) for the collection of the data.
- 1.Mirnezami R, Mehta AM, Chandrakumaran K, et al. Cytoreductive surgery in combination with hyperthermic intraperitoneal chemotherapy improves survival in patients with colorectal peritoneal metastases compared with systemic chemotherapy alone. Br J Cancer. 2014;111:1500–8.CrossRefPubMedPubMedCentralGoogle Scholar
- 4.Cavaliere F, De Simone M, Virz S, et al. Prognostic factors and oncologic outcome in 146 patients with colorectal peritoneal carcinomatosis treated with cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy: Italian multicenter study S.I.T.I.L.O. Eur J Surg Oncol. 2011; 37: 148–54.Google Scholar
- 7.Esquivel J, Lowy AM, Markman M, et al. The American Society of peritoneal surface malignancies (ASPSM) multi-institution evaluation of the peritoneal surface disease severity score (PSDSS) in 1,013 patients with colorectal cancer with peritoneal carcinomatosis. Ann Surg Oncol. 2014;21:4195.CrossRefGoogle Scholar
- 12.COMPASS. Simkens GA, van Oudheusden TR, Nieboer D, et al. Development of a prognostic nomogram for patients with peritoneally metastasized colorectal cancer treated with cytoreductive surgery and HIPEC. Ann Surg Oncol. 2016;23:4214–21.Google Scholar
- 21.Prada-Villaverde A, Esquivel J, Lowy AM, et al. 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. J Surg Oncol. 2014. https://doi.org/10.1002/jso.23728.