eP276 - A Two-Stage Cytoreductive Surgery with a Second Stage Hyperthermic Intraperitoneal Chemotherapy for Peritoneal Surface Malignancies

Purpose/Background: Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) is an essential option for peritoneal surface malignancies (PSM), with desirable outcomes relating to survival and quality of life. CRS-HIPEC, may be associated with increased morbidity that may impact on disease-related outcomes. We propose a wider use of a two-stage approach—wherein CRS and HIPEC are done on separate operative dates. This study will review and analyze eleven such cases in our institutionMethods/Interventions: A retrospective study was conducted on all adult cases who underwent a two-stage CRS-HIPEC from 2013 to 2023. The following data were obtained: patient demographics, type of PSM, peritoneal carcinomatosis index (PCI), time interval to second surgery, operative times, postoperative length of stay (LOS)--from the first procedure, and 30-day outcomesResults/Outcomes: Eleven patients underwent a two-stage CRS-HIPEC, with a mean age of 53 years. Most were female. The mean PCI was 11, with complete cytoreduction already achieved during the initial surgery in 7 (63%) patients—requiring only HIPEC on the second surgery. Further CRS, in the second surgery, was done prior to HIPEC in the other four.The median duration of the first procedure was 366 minutes, the second was 340 minutes. Time interval between the two surgeries was 6 days and the average total LOS was 16 days . No mortalities were reported.Conclusion/

Discussion: In our setting, many patients with PSM needing CRS-HIPEC have advanced disease (high PCI), require multivisceral resection, have undergone prior laparotomies, and are of poor nutritional (hypoalbuminemia) and functional status. The proposition for a two-stage procedure arose from cases with PSM, who may benefit from HIPEC, but were not recognized preoperatively (e.g. perforated appendiceal mucocoele diagnosed as appendicitis, carcinomatosis not seen on imaging). Logistical concerns restrict us from delivering HIPEC at the time of discovery of the more extensive abdominal disease. Thus, the need to resort to a second stage. From this experience, we saw the potential benefits a two-stage procedure may have on sicker patients, those needing a more formidable cytoreduction, or both. It is vital that the second procedure be done within ten days from the first, prior to the onset of obliterative peritonitis.Among those where CRS was not completed during the first surgery, reasons for non-completion were: persistent hypotension, significant blood loss (>1000cc), prolonged surgery(>10 hours), or a combination of these. These were optimized prior to the second procedure, with completion of CRS + HIPEC done later. Thus, we can recommend that termination of the initial CRS should be considered, and second stage procedure be planned when the mentioned factors are encounteredThe study showed that performing a two-stage procedure is safe with comparable oncologic and patient outcomes. We propose a wider use of a two-staged approach for CRS-HIPEC, not only as a bail-out procedure, but as a planned two-stage procedure—for patients with disease- and patient-related factors predictive of a potential volatile perioperative course. This strategy may be best for complex peritoneal diseases with significant medical concerns.Patient Characteristics and Identified Clinical Outcomes