Percutaneous omental biopsy: efficacy and complications.

PURPOSE: To determine the efficacy and safety of percutaneous omental biopsy.

METHODS: Retrospective review was performed of all 181 percutaneous omental biopsies performed at a single institution between 9/18/2002 and 2/12/2016. Mean patient age was 67 (±14) years, and 114 (63%) patients were female. Biopsy results were compared to subsequent surgical pathology and paracentesis cytology, when available, and cases were further evaluated based on the imaging appearance of the omental abnormality. Complications were classified using Society of Interventional Radiology (SIR) consensus guidelines.

RESULTS: Of the 181 cases, histopathology was positive for malignancy in 166 (92%) patients and showed benign inflammation/fibrosis in 15 (8%) patients. Seventy-three (40%) patients underwent subsequent surgery, and omental malignancy was diagnosed in every case. Percutaneous omental biopsy and surgical pathology results were concordant in all but 1 case (diagnostic accuracy of 99%). In contrast, the accuracy of paracentesis cytology in surgically confirmed malignant cases was only 76% (p = 0.004). Biopsy was positive for malignancy in 95% of patients with omental caking, 92% with omental nodularity, 80% with a single omental nodule, and 20% with omental thickening (p = <0.001). In 118 (65%) patients, a previously unknown (new or additional) malignancy was diagnosed. No clinically significant complications occurred.

CONCLUSIONS: Percutaneous biopsy is an effective and safe method to evaluate omental abnormalities. Omental biopsy is more sensitive than paracentesis cytology for determining malignancy. Omental malignancy is more likely as the abnormality advances through the spectrum of imaging appearances from omental thickening to omental caking.