Accuracy of MDCT in the preoperative definition of peritoneal cancer index (PCI) in patients with advanced ovarian cancer who underwent peritonectomy and hyperthermic intraperitoneal chemotherapy (HIPEC)

Due to the lack of specific symptoms and early tendency to peritoneal dissemination, epithelial ovarian cancer is most commonly detected in an advanced stage after it has spread into the peritoneal cavity (stage FIGO III), when the overall five-year survival rate is 30-40%. Peritoneal carcinomatosis (PC) is a clinical entity with unfavourable prognosis that commonly characterises the terminal evolution of abdominopelvic neoplastic diseases. Being particularly difficult to treat, cancers with widespread peritoneal dissemination often cause their great morbidity and mortality through progressive involvement of the peritoneal surfaces. The standard treatment of ovarian cancer with peritoneal dissemination involves optimal surgical cytoreduction (CRS) followed by platinum/taxane based chemotherapy. However, despite the notable chemosensitivity of this neoplasm, tumor recurrence occurs in most cases, particularly when extra-pelvic peritoneal dissemination is present, resulting in very low long-term survival probability. Hyperthermic intraperitoneal chemotherapy (HIPEC) is a locoregional treatment which involves the washing of peritoneal cavity with heated solutions and high drug concentrations. The rationale for HIPEC is based on direct cytotoxicity of hyperthermia against malignant cells, combined with heat-related enhanced cytotoxic effects and pharmacokinetic advantages of the intraperitoneal route of anticancer drug. In the treatment of peritoneal carcinomatosis HIPEC is generally associated with surgical debulking and peritonectomy, with the aim to remove macroscopic tumor. Theoretically, CRS is performed to treat the macroscopic disease and HIPEC to treat the microscopic residual disease, eradicating neoplastic disease in a single procedure. This advanced multimodality treatment has shown significant improvement in long-term results with respect to the conventional treatment. Preoperative imaging, essentially CT and MRI, that theoretically could assist not only in planning cytoreduction but also in preventing unwarranted laparotomy in patients with unresectable disease, are currently limited in the ability to reliably visualize localised peritoneal carcinomatosis, having decreased sensitivity for low-volume disease. The extent of peritoneal dissemination at the time of surgery and HIPEC is generally scored according to the Peritoneal Cancer Index (PCI), described by Jacque and Sugarbaker, which is commonly used for the classification of peritoneal carcinomatosis from different diseases. The PCI has been shown to have prognostic value: it is a quantitative indicator of PC useful to guide selection of patients who are most likely to respond to the treatment and to exclude those who have little or no chance of benefiting [3], allowing to estimate with reasonable accuracy the probability of complete cytoreduction; proving to be a prognostic indicator for survival. The aim of our work has been to evaluate the accuracy of MDCT in the preoperative definition of PCI in patients with advanced ovarian cancer who underwent peritonectomy and HIPEC after neoadjuvant chemotherapy, in order to obtain a pre-surgery prognostic evaluation and a prediction of optimal cytoreduction.