The role of molecular biomarkers in outcomes and patient selection for cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for peritoneal metastases of colorectal origin.

BACKGROUND: Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) is effective in select patients with peritoneal metastases of colorectal (CRC) origin. The impact of different biomarkers in predicting recurrence after CRS/HIPEC is unclear. METHODS: Retrospective review of patients who underwent CRS/HIPEC for PC of CRC origin from 03/2007-08/2017. Molecular profile of the primary tumor was obtained from pathology reports, whenever available. RESULTS: Overall, 100 patients underwent CRS/HIPEC for peritoneal metastases of CRC origin. Most patients presented high grade tumor histology (G2/G3, n = 97, 97%), and a majority showed mucinous features (n = 61, 61%). At a median follow-up of 18 months, median DFS for the overall population was 13 months (95% CI 9.6, 16.4). Data reporting at least one mutational analysis was available in 64 patients. Microsatellite stability was detected in 42/50 (84%) patients, mKRAS in 25/51 (49%), and mBRAF in 5/35 (14.3%). On Kaplan-Meier analysis, BRAF was the only mutation associated with poor DFS (16 months, CI 95% 11.7-43.3 vs. 7 months, CI 95% 2.1-11.9, p = .008). On multivariate analysis, mBRAF independently predicted earlier recurrence (p = .032). CONCLUSIONS: In this analysis, mBRAF was independently associated with earlier recurrence in patients undergoing CRS/HIPEC for CRC, leading to dismal median DFS (7 months). Strict patient selection is advisable in these patients.

The Safety of Iterative Cytoreductive Surgery and HIPEC for Peritoneal Carcinomatosis: A High Volume Center Prospectively Maintained Database Analysis.

INTRODUCTION: Offering iterative cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) for recurrence of peritoneal carcinomatosis (PC) poses a surgical dilemma. Safety of this repeated operation in the short and long term has not been largely investigated. METHODS: Patients with PC who underwent 377 CRS/HIPEC procedures between 2007 and 2018 at our institution were included from a prospectively maintained database. Outcomes for patients who had singular CRS/HIPEC were compared with those for patients who had repeated CRS/HIPEC. RESULTS: Overall, there were 325 singular and 52 iterative CRS/HIPEC procedures performed during this time period. Age, sex, and ASA class were comparable between cohorts (p = NS). Optimal cytoreduction, mean operative time, mean length of hospital stay, 90-day major morbidity, and 90-day mortality were also similar. At a median follow-up of 24 months, there was no significant difference in recurrence rate (%, 60 vs 63, p = 0.76), disease-free survival (mean months, 19 vs 15, p = 0.30), and overall survival (mean months, 32 vs 27, p = 0.69). The iterative CRS/HIPEC group had significantly higher rates of major late complications than the singular CRS/HIPEC group (%, 18 vs 40, p < 0.01). CONCLUSION: Repeated CRS/HIPEC for PC has similar perioperative morbidity and mortality, as well as long-term oncological benefits, when compared with singular CRS/HIPEC. However, more than twice as many patients undergoing iterative CRS/HIPEC suffered from major late complications.

Surveillance of Low-Grade Appendiceal Mucinous Neoplasms With Peritoneal Metastases After Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy: Are 5 Years Enough? A Multisite Experience.

BACKGROUND: Low-grade appendiceal mucinous neoplasms (LAMNs) are tumors that often present with widespread mucin in the peritoneal cavity (pseudomyxoma peritonei [PMP]). Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) are effective treatment, but no published recommendations exist regarding surveillance. METHODS: Data from prospective databases of patients who underwent CRS-HIPEC from 2001 to 2017 at two high-volume institutions were retrospectively analyzed. Patients who underwent complete CRS-HIPEC for PMP secondary to LAMN were included in the analysis. Pathologic examination confirmed the diagnosis of LAMN. Cases of mucinous adenocarcinomas and neuroendocrine tumors (goblet cell carcinoids) were excluded. RESULTS: The study enrolled 156 patients. The median peritoneal cancer index (PCI) was 18 (interquartile range IQR1-3, 12-23), and 125 patients (80.1%) had a CC0 cytoreduction. According to American Joint Committee on Cancer (AJCC) grading, 152 patients (97.4%) presented with acellular mucin or G1 implants, 2 patients (1.3%) presented with G2 disease, and 2 patients (1.3%) presented with G3 disease. During the follow-up period (median, 45 months; IQR1-3 23-76 months), 23 patients (14.7%) experienced recurrence. All the recurrences were peritoneal and occurred within 5 years. The 1-, 3-, and 5-year disease-free survival (DFS) rates were respectively 95.5%, 83.4%, and 78.3%. Univariate Cox regression analysis showed that higher PCI scores (p < 0.001), a CC1 cytoreduction (p = 0.005), and higher preoperative levels of carcinoembryonic antigen (CEA) (p = 0.012) and CA-125 (p = 0.032) correlated with a shorter DFS. Only higher PCI scores independently predicted earlier recurrences (p < 0.001). CONCLUSION: Most patients had recurrence within 3 years after CRS-HIPEC, and none after 5 years. High PCI was the only independently significant variable. The study findings support intensive surveillance (every 3-6 months) with tumor markers and imaging methods during the first 3 years, and annual surveillance thereafter, with follow-up assessment after 5 years yielding limited benefit.

Correction to: Surveillance of Low-Grade Appendiceal Mucinous Neoplasms With Peritoneal Metastases After Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy: Are 5 Years Enough? A Multisite Experience.

In the original version of the article, Margaret Hofstedt's last name was misspelled.