CORRELATION BETWEEN PATHOLOGIC AND INTRAOPERATIVE FINDINGS IN PATIENTS UNDERGOING PERITONEAL ONCOLOGIC SURGERY

Abstract

Abstract Introduction Surgical Peritoneal Carcinomatosis Index (PCIq) subjectively calculated during surgery is a universally accepted value, both selective and prognostic. Calculation of PCI based on anatomopathological findings (PCIp) could be a more reliable value of tumor burden. We compare the differences between PCIq and PCIp by evaluating the prognostic significance and usefulness of PCIp. Methods We conducted a retrospective study of patients undergoing cytoreduction surgery and HIPEC between 2015 and 2019 in our General Surgery Department. Resected specimens were classified according to their definitive pathological anatomy for the calculation of PCIp, and compared with PCIq for each patient. ROC curves were applied to compare the prognostic value of both PCIs. Results Within the 68 procedures, the difference between PCIq and PCIp was 1.19 (0–8), with a total concordance in 53% of the cases. The discordance did not depend on the type of tumor, previous surgeries or neoadjuvant treatment. In 75% of the procedures there were negative samples for malignancy, which was associated with a higher disease-free survival (p = 0.017). ROC curves showed that PCIp was similar to PCIq as a predictor of survival or recurrence, with the number of positive resected specimens being the best predictor of recurrence (p = 0.035). Conclusions PCIq overestimates tumor burden, as the presence of negative specimens is frequent. PCIp does not seem to be a better tool for predicting recurrence or survival in our series. The number of positive samples more accurately estimates the probability of recurrence than PCIq, which may have prognostic significance.