Diagnosis and treatment of peritoneal carcinomatosis - a comprehensive overview.

Peritoneal carcinomatosis, which is the most common malignant process of the peritoneal cavity, originates mostly from colorectal, gastric, and gynaecological malignancies. The differential diagnosis is broad and covers primary peritoneal malignancies, as well as many benign disorders such as endometriosis, and inflammatory and infectious diseases. Peritoneal implants tend to locate in the areas of the physiological stasis of the peritoneal fluid: pelvic peritoneal reflections, right and left paracolic gutters, superior part of the sigmoid mesocolon, ileocolic area, and the right subdiaphragmatic space. The 3 most common imaging findings are ascites, nodular implants, and infiltration of the peritoneal fatty tissue. Several imaging modalities may be applied in patients with peritoneal carcinomatosis. Ultrasound has low sensitivity and specificity, and therefore plays only a marginal role. Computed tomography is the method of choice, due to its availability, cost-effectiveness, and relatively high sensitivity. The sensitivity of magnetic resonance imaging depends on the size of peritoneal implants - in cases of implants larger than 10 mm is comparable to CT. Some studies suggest that PET/CT may be the most sensitive method, yet its usefulness in everyday practice is controversial. The Peritoneal Carcinomatosis Index (PCI) is a scale used to assess the tumour burden in the peritoneum and may serve as a communication tool between clinicians and radiologists. The imaging findings may influence the surgeon's decision on performing cytoreductive surgery, which may be followed by intraperitoneal chemotherapy (HIPEC or EPIC procedures). The introduction of these therapeutic methods has significantly improved the life expectancy of patients with peritoneal carcinomatosis.