Peritoneal Carcinomatosis and Its Mimics: Review of CT Findings for Differential Diagnosis

Our plain-English summary of Peritoneal Carcinomatosis and Its Mimics: Review of CT Findings for Differential Diagnosis, by J.H. Cho, S.S. Kim (Journal of the Belgian Society of Radiology, 2020).

The study

• Authors: J.H. Cho, S.S. Kim
• Journal: Journal of the Belgian Society of Radiology
• Published: 2020;104(1):8
• Type of article: Case report
• Cited by: 22 articles, as counted by NIH iCite
• Read it: PubMed · Publisher · Free full text

Abstract

Peritoneal carcinomatosis (PC) indicates the metastasis of a malignant neoplasm to the peritoneal surface. PC can be incidentally detected before discovery of the primary malignancy during an imaging study. There are other conditions that can mimic PC, such as pseudomyxoma peritonei, peritoneal lymphomatosis, peritoneal malignant mesothelioma, leiomyomatosis peritonealis disseminata, and tuberculous peritonitis. These diseases may appear similar on computed tomography (CT), but there are some clues for the differential diagnosis. This article will describe the CT findings of PC and its mimics for the differential diagnosis.

Copyright: © 2020 The Author(s).

In plain English

This article was a pictorial essay, a type of review. It did not report a study of a measured group of patients. Drawing on earlier published work, and illustrated with CT images of individual patients, it described how peritoneal carcinomatosis (cancer that has spread to the lining of the abdomen) looks on computed tomography (CT) scans. It also described how several conditions that can look similar might be told apart: pseudomyxoma peritonei, peritoneal lymphomatosis, peritoneal malignant mesothelioma, leiomyomatosis peritonealis disseminata and tuberculous peritonitis. For peritoneal malignant mesothelioma, the authors wrote that it is difficult to distinguish from peritoneal carcinomatosis by abdominal imaging alone, but that a history of asbestos exposure or the presence of pleural plaques could help. Citing earlier literature, they stated that 6%–10% of malignant mesotheliomas originate from the peritoneum. One illustrated case was an 80-year-old woman with peritoneal malignant mesothelioma and a history of asbestos exposure, whose chest CT showed multiple calcified pleural plaques. The authors concluded that telling peritoneal carcinomatosis apart from tuberculous peritonitis on CT remains a challenge.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: Pictorial essay (narrative review of CT findings, illustrated with individual patient images)
• Who was studied: No study population. The article is illustrated with CT images of single patients, including an 80-year-old woman with peritoneal malignant mesothelioma and a history of asbestos exposure.
• Exposure: Asbestos exposure was not studied as such. It was mentioned only as a clue that could help tell peritoneal malignant mesothelioma apart from peritoneal carcinomatosis. No fiber types were named.
• Main results:
  • The authors described the typical CT findings of peritoneal carcinomatosis as multifocal discrete nodules to infiltrative masses, omental haziness, ascites, and peritoneal thickening, nodularity and enhancement.
  • Scalloping of the surfaces of abdominal organs was described as a typical CT finding in pseudomyxoma peritonei.
  • Coexisting splenomegaly (enlarged spleen) and extensive lymphadenopathy (enlarged lymph nodes) were described as features suggesting peritoneal lymphomatosis over peritoneal carcinomatosis.
  • Citing earlier literature, the authors stated that most malignant mesotheliomas arise from the pleura, but 6%–10% originate from the peritoneum.
  • The authors wrote that peritoneal malignant mesothelioma is difficult to distinguish from peritoneal carcinomatosis by abdominal imaging findings alone.
  • In the illustrated case of peritoneal malignant mesothelioma (an 80-year-old woman with a history of asbestos exposure), chest CT showed multiple calcified plaques in both pleura.
  • Leiomyomatosis peritonealis disseminata was described as appearing on CT as well-circumscribed solid masses with smooth contour.
  • The authors stated that tuberculous peritonitis is difficult to differentiate from peritoneal carcinomatosis in daily practice.
• The authors' conclusion: The authors concluded that pseudomyxoma peritonei, peritoneal lymphomatosis, peritoneal malignant mesothelioma and leiomyomatosis peritonealis disseminata can be distinguished from peritoneal carcinomatosis by certain findings, including a history of asbestos exposure or pleural plaques for mesothelioma. They also concluded that distinguishing peritoneal carcinomatosis from tuberculous peritonitis on CT remains a challenge.

Topics

Medical terms in this study, explained in our Lexicon: Differential Diagnosis, Metastasis, Neoplasm, Discovery, Mesothelioma.

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