Fine-needle trucut biopsy versus fine-needle aspiration cytology with ultrasound guidance in the abdomen

Historically, fine-needle aspiration cytology (FNAC) has varying sensitivity, specificity and accuracy in the diagnosis of abdominal lesions with a high insufficient sampling rate. We compared 20-G fine-needle trucut biopsy (FNTB) with FNAC results in the biopsy of solid abdominal tumours. A retrospective review of 171 (128x 20-G FNTB and 43x FNAC) ultrasound-guided biopsies of abdominal tumours on 157 patients (male : female 85:72, mean age 61.25 years) were carried out. One hundred and seventy-one biopsies were carried out: liver 109, pancreas 19, lymph node 10, omentum 5, right iliac fossa mass 6, adrenal 6 and others 16. An average of 2.06 and 1.97 passes (range 1-4) were carried out per FNTB and FNAC, respectively. A definitive diagnosis was made in 122/128 biopsies (95.3%) and 32/43 biopsies (74.4%) for FNTB and FNAC, respectively. Diagnoses consisted of metastatic liver disease (74/171), pancreatic adenocarcinoma (10/171), lymphoma (8/171) and others (33/171) and benign (29/171). No significant complications occurred in either group. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 87, 100, 100, 50, 84.4 and 93.1, 100, 100, 60, 71.4 for FNTB and FNAC, respectively. A greater and more consistent positive diagnosis rate is yielded by 20-G FNTB (95.3%) than FNAC (74.4%). The diagnostic accuracy of FNTB is 84.4% compared with 69.8% for FNAC. A greater insufficient sampling rate occurs with FNAC (25.6%) than with FNTB (4.7%). For abdominal biopsy, 20-G FNTB needles have a much higher yield than FNAC with no increase in complications. FNTB is the preferred choice, particularly where cytological assistance at the time of biopsy is unavailable.