Endometriosis shows key features on CT

Careful review of the features of abdominal wall masses identified on CT imaging may help to distinguish abdominal wall endometriosis (AWE) from other abdominal wall masses, according to the findings of a recently published retrospective study.¹ “There is a broad differential diagnosis for abdominal wall masses and the patient’s history and clinical presentation may not always point to the correct diagnosis. The identification of CT features that can discriminate AWE from other abdominal wall masses is important because it can facilitate an accurate diagnosis at the time of image interpretation that will allow for proper patient counseling and optimal management,” said Gail Yarmish, MD, lead author and radiologist, Staten Island University Hospital, New York, New York. “Diagnosis of AWE may obviate the need for resection, or if resection is deemed necessary in a particular clinical scenario, the information from the CT interpretation may guide the radicality of dissection and the need for complex abdominal wall reconstruction.”

Dr Yarmish told Contemporary OB/GYN that she became interested in undertaking the study after noticing that cases of AWE had a unique appearance on CT. Searching the literature on this topic, however, Dr Yarmish found no studies that aimed to delineate potential discriminating features of AWE. Blinded to the patients’ histopathologic diagnosis from biopsy/resection of the abdominal wall mass, Dr Yarmish and Dr H Alberto Vargas, a radiologist at Memorial Sloan Kettering Cancer Center, New York, New York, retrospectively reviewed CT images from 105 adult women seen consecutively at their 2 institutions.

NEXT: Study results >>

AWE was the most common histological diagnosis in the group (24.5%) followed by adenocarcinoma (21%), desmoid (14.3%), and leiomyosarcoma (8.6%). A total of 15 qualitative CT features were recorded and then analyzed for statistical associations with a diagnosis of AWE. The evaluations by both radiologists were consistent in identifying 3 features as being associated with AWE-location below the umbilicus, homogenous density, and presence of linear infiltration irradiating peripherally from a central soft tissue nodule.

Analyses of the performance of the individual features or various combinations of the 3 for predicting the diagnosis of AWE showed presence of all 3 features had the highest sensitivity (69%) and specificity (97%). Dr Yarmish noted to Contemporary OB/GYN that she and her co-authors are not making a recommendation to use CT for diagnosing endometriosis, but only defining key imaging features for differentiating AWE from other etiologies when an abdominal wall mass is encountered. 

Reference

1. Yarmish G, Sala E, Goldman DA, et al Abdominal wall endometriosis: differentiation from other masses using C T features. Abdom Radiol (NY). 2016 Dec 21. [Epub ahead of print]