Abdominal wall endometriosis: differentiation from other masses using CT features
To assess the utility of morphologic and quantitative CT features in differentiating abdominal wall endometriosis (AWE) from other masses of the abdominal wall.
Retrospective IRB-approved study of 105 consecutive women from two institutions who underwent CT and biopsy/resection of abdominal wall masses. CTs were independently reviewed by two radiologists blinded to final histopathologic diagnoses. Associations between CT features and pathology were tested using Fisher’s Exact Test. Sensitivity, specificity, positive, and negative predictive values were calculated. P values were adjusted for multiple variable testing.
24.8% (26/105) of patients had histologically proven abdominal wall endometriosis. The other most common diagnoses included adenocarcinoma NOS (21%; 22/105), desmoid (14.3%; 15/105), and leiomyosarcoma (8.6%; 9/105). CT features significantly associated with endometriosis for both readers were location below the umbilicus (P = 0.0188), homogeneous density (P = 0.0188), and presence of linear infiltration irradiating peripherally from a central soft tissue nodule (i.e., “gorgon” sign) (P < 0.0001). The highest combined sensitivity (0.69, 95% CI: 0.48–0.86) and specificity (0.97, 95% CI: 0.91–1.00) for both readers occurred for patients having all three of these features present. Border type (P = 0.0199) was only significant for R2, peritoneal extension (P = 0.0188) was only significantly for R1, and the remainder of features were insignificant (P = 0.06–60). There was overlap in Hounsfield units on non-contrast CT (N = 26) between AWE (median: 45HU, range: 39–54) and other abdominal wall masses (median: 38.5HU, range: 15–58).
CT features are helpful in differentiating AWE from other abdominal wall soft tissue masses. Such differentiation may assist decisions regarding possible biopsy and treatment planning.
KeywordsEndometriosis Abdominal wall CT
Compliance with ethical standards
This research was funded in part through the NIH/NCI Cancer Center Support Grant P30 CA008748.
Conflict of interest
The authors declare that they have no conflict of interest.
All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Ethical approval was granted by the IRB of both institutions.
IRB of both institutions waived the requirement for informed consent.
- 12.Giudice LC, Swiersz LM, Burney RO (2010) Endometriosis. In: Jameson JL, De Groot LJ (eds) Endocrinology, 6th edn. New York: Elsevier, pp 2356–2370Google Scholar