Background: The greater omentum can serve as a useful target for percutaneous biopsy; in clinical practice, CT is commonly used for biopsy guidance. Purpose: To evaluate the diagnostic yield of percutaneous ultrasound (US)-guided omental biopsy and to explore the association of diagnostic yield with pre-biopsy diagnostic CT findings. Methods: This retrospective study included 163 patients (mean age, 65±12 years; 120 women, 43 men; mean BMI, 28.9±7.9) who underwent US-guided omental biopsy between 2002-2020 at a single institution at which US served as the firstline modality for omental biopsy guidance. Biopsies were performed by abdominal radiologists without dedicated interventional radiology fellowship training. Post-biopsy clinical and imaging follow-up were reviewed to establish each patient's ultimate diagnosis. Omental biopsies were characterized as diagnostic or non-diagnostic relative to the ultimate diagnosis. Associations were explored between diagnostic yield and findings on pre-biopsy CT and biopsy US. Results: US-guided omental biopsy was performed by 18-gauge core in 156 and fine-needle aspiration in 7 patients. Mean passes was 2.5±1.0. Mean omental thickness was 2.6±1.2 cm. On pre-biopsy diagnostic CT, omental disease appeared infiltrative in 127 (78%) versus mass-forming in 36 (22%), and appeared hypoechoic in 105 (64%) versus iso-to-hyperechoic in 58 (36%). The ultimate diagnosis was malignant in 154 (95%) [gynecologic in 82 (most commonly high-grade serous adenocarcinoma, n=56) and gastrointestinal in 45] and benign in 9 (6%). The omental biopsy was diagnostic relative to the ultimate diagnosis in 155 (95%). A diagnostic versus non-diagnostic biopsy was not associated (p>.05) with age, BMI, number of passes, or omental target thickness or attenuation. A total of 94% (120/127) of infiltrative and 97% (35/36) of mass-forming cases were diagnostic (p=.50). A total of 96% (102/106) of hypoechoic and 93% (53/57) of iso-to-hyperechoic cases were diagnostic (p=.36). No complication occurred. Conclusion: US-guided biopsy of omental disease suspected on CT is safe and effective for tissue diagnosis. Though omental disease commonly appears on US as diffuse infiltrative thickening without a discrete target, sampling based on pre-biopsy CT landmarks is diagnostic in the large majority of cases. Clinical Impact: US should be considered the first-line modality for omental biopsy guidance when feasible.
Background: The greater omentum can serve as a useful target for percutaneous biopsy; in clinical practice, CT is commonly used for biopsy guidance. Purpose: To evaluate the diagnostic yield of percutaneous ultrasound (US)-guided omental biopsy and to explore the association of diagnostic yield with pre-biopsy diagnostic CT findings. Methods: This retrospective study included 163 patients (mean age, 65±12 years; 120 women, 43 men; mean BMI, 28.9±7.9) who underwent US-guided omental biopsy between 2002-2020 at a single institution at which US served as the firstline modality for omental biopsy guidance. Biopsies were performed by abdominal radiologists without dedicated interventional radiology fellowship training. Post-biopsy clinical and imaging follow-up were reviewed to establish each patient's ultimate diagnosis. Omental biopsies were characterized as diagnostic or non-diagnostic relative to the ultimate diagnosis. Associations were explored between diagnostic yield and findings on pre-biopsy CT and biopsy US. Results: US-guided omental biopsy was performed by 18-gauge core in 156 and fine-needle aspiration in 7 patients. Mean passes was 2.5±1.0. Mean omental thickness was 2.6±1.2 cm. On pre-biopsy diagnostic CT, omental disease appeared infiltrative in 127 (78%) versus mass-forming in 36 (22%), and appeared hypoechoic in 105 (64%) versus iso-to-hyperechoic in 58 (36%). The ultimate diagnosis was malignant in 154 (95%) [gynecologic in 82 (most commonly high-grade serous adenocarcinoma, n=56) and gastrointestinal in 45] and benign in 9 (6%). The omental biopsy was diagnostic relative to the ultimate diagnosis in 155 (95%). A diagnostic versus non-diagnostic biopsy was not associated (p>.05) with age, BMI, number of passes, or omental target thickness or attenuation. A total of 94% (120/127) of infiltrative and 97% (35/36) of mass-forming cases were diagnostic (p=.50). A total of 96% (102/106) of hypoechoic and 93% (53/57) of iso-to-hyperechoic cases were diagnostic (p=.36). No complication occurred. Conclusion: US-guided biopsy of omental disease suspected on CT is safe and effective for tissue diagnosis. Though omental disease commonly appears on US as diffuse infiltrative thickening without a discrete target, sampling based on pre-biopsy CT landmarks is diagnostic in the large majority of cases. Clinical Impact: US should be considered the first-line modality for omental biopsy guidance when feasible.
Authors: Amjad Alhyari; Christian Görg; Christoph Frank Dietrich; Corrina Trenker; Lena Strauch; Ehsan Safai Zadeh Journal: BMJ Open Gastroenterol Date: 2022-05