To define Peritoneal Carcinomatosis and to briefly review its pathogenesis, the modalities in which peritoneal metastases spread, the importance of peritoneal boundaries, of peritoneal spaces and peritoneal fluid circulation. To review CT appearance of peritoneal carcinomatosis underlying some typical aspects and sites that radiologists have to check to make a detail report. To propose a new reporting scheme.

Definition: Peritoneal Carcinosis is defined as seeding and implantation of neoplastic cells into peritoneal cavity and may represents the advanced evolutive stage of every tumors developed into abdominal and pelvic organs. However ovarian, stomach and colorectal cancers accounts for almost all case 1-2. Furthermore, there are also tumors, even though rare, that develop directly from peritoneum (mesothelioma) or extraperitoneal organs (breast cancer). When the disease increases, the tumoral cells reach and affect the membrane covering the same organs (visceral peritoneum). Once this “barrier” has been...

CT imaging of peritoneal carcinomatosis Peritoneal Carcinosis is characterized by the presence of neoplastic implants with different morphological features and distribution in peritoneal cavity (6-10). Radiologist should evaluate: 1. Morphology 2. Localization Morphological aspects: There are three board categories: Solid implants Cystic implants Mixed implants In all types of categories calcifications can be present or not. Solid, cystic and mixed implants can present with different patterns that depicts typical aspects of peritoneal carcinomatosis (10). Micronodular Pattern Micronodular pattern is characterized by the presence of tiny...

Pretreatment approach to Peritoneal Carcinomatosis requires an accurate staging with detailed information about number of implants and sites involved. Knowledge of patterns of peritoneal carcinomatosis and sites most frequently involved is crucial for radiologists. A reporting scheme is necessary to lead report and description of disease.

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