E351: Minimally Invasive Approach to Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy Improves Perioperative Outcomes

Introduction: Minimally invasive surgery (MIS) is gaining recognition for its potential to achieve comparable oncological outcomes while reducing morbidity and mortality in various cancer surgeries. Limited data are available regarding the short and long-term effects of MIS in the context of cytoreduction (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC).

Methods: A retrospective analysis of our institutional prospectively maintained CRS database was performed. Patients who underwent open or MIS CRS and HIPEC between 2017 and 2023 were included. Associations of surgery type with demographic and clinical characteristics were examined using chi-square tests for categorical variables and two sample t-tests for continuous variables. Propensity scores were generated using logistic regression analysis, modeling surgery type as the outcome variable and all statistically significant (p< 0.05) demographic and clinical variables as exposures with resulting weights applied to outcomes associations to account for BMI, tumor histology and peritoneal carcinomatosis index (PCI) between groups.   

Results: Among 154 patients, 124 (80.5%) underwent open CRS and 30 (19.5%) MIS CRS, (26 robotic and 4 laparoscopic). Prior to propensity score weighting, MIS and open groups differed significantly with regards to tumor histology (appendiceal most common for open group (50.8%) vs gastric in MIS group (48.3%), p< 0.0001), BMI (45.5% with BMI < 25 in open vs 20.0% in MIS group, p< 0.012), and PCI (50.4% in open group with PCI ≥ 10 vs 16.7% in MIS group, p=0.01). Post propensity weighting, these differences were no longer statistically significant. Complete cytoreduction (CC0) was 90% in MIS and 74% in open (p=0.26). MIS group had significantly fewer post-operative complications with lower rates of deep space infection (6.7% vs. 17.2%, p=0.014), acute kidney injury (6.7% vs. 26.8%, p=0.026), and grade ≥3 Clavien-Dindo complications (10% vs. 32.3%, p=0.004). MIS approach was also associated with a lower transfusion requirement ((13.3% vs. 48.8%, p< 0.0001), shorter length of stay (mean 5.2 vs. 11 days, p=0.04), and reduced 30-day readmissions (16.7% vs. 26.8%, p=0.0034).

Conclusions: Minimally invasive CRS and HIPEC, when selectively performed, showed improved perioperative outcomes including fewer complications, shorter stay, and fewer readmissions. Complete oncologic resections were achieved safely across various tumor histologies. Future studies are needed to validate the long-term oncologic safety of MIS CRS and HIPEC.