Malignant disease is a leading cause of pleural effusion, with about 40 000 cases occurring annually in the UK and 175 000 in the USA. Pleural fluid cytology establishes a diagnosis in only 60% of these effusions. Pleural biopsy using an Abram’s needle, first introduced in 1958, is routinely performed for establishing a diagnosis in the remaining cases. This procedure has a low sensitivity and is associated with numerous complications. Undiagnosed patients may either have to undergo the procedure again or be referred for a thoracoscopic biopsy.

In this single centre, prospective, parallel, randomised study the authors compared CT-guided needle biopsy with standard pleural biopsy using Abram’s needle. Fifty patients with cytologically negative unilateral and exudative pleural effusions were randomised to undergo either CT-guided pleural biopsy or Abram’s pleural biopsy performed by a single competent operator. Three patients did not undergo the procedure at all and, of the remaining 47, 24 underwent Abram’s biopsy while 23 underwent CT-guided biopsy. The results showed that sensitivity for pleural malignancy with the CT-guided procedure was 87% compared with 47% with Abram’s needle. Although the specificity and positive predictive value for both CT-guided biopsy and Abram’s biopsy were the same at 100% each, the negative predictive value of CT-guided biopsy was superior at 80% compared with 44% with Abram’s needle.