[Diagnostic rentability of close pleural biopsy: Tru-cut vs. Cope]

The prevalence of pleural effusion in Mexico is over 400 per 100 000 inhabitants. The etiology is infectious in 45.7% and neoplastic in 32.6%. Closed pleural biopsy sensibility is 48-70% in cancer and 50-59% in tuberculosis using Cope or Abrams needle. In 1989, Tru-cut needle biopsy was described in a small study for massive pleural effusions with a sensibility of 86%. Our Institute has a wide experience with this infrequently procedure with reliable results than using Cope needle. Diagnostic yield should be evaluated. We aimed to evaluate the diagnostic yield of Tru-cut vs. standard Cope biopsy in the histopathological diagnosis of pleural effusion.

Experimental, not blinded, analytical, cross-sectional study. We studied 44 patients (24 male and 20 female) with exudative pleural effusion over a period of 14 months. Every patient underwent four Tru-cut and four Cope needle biopsies. The diagnostic yield of both methods was compared.

The mean age of patients was 61.4 ± 12.2 years. The diagnosis was achieved in 25 (57%) of patients using Tru-cut and 22 (50%) of patients using Cope's closed pleural biopsy. The diagnostic value was not significantly higher (p = 0.41). The most common diagnoses were adenocarcinoma (20.5%), mesothelioma (15.9%) and tuberculosis (15.9%).

The diagnostic yield of Tru-cut needle biopsy is slightly higher than Cope pleural biopsy, very similar to that reported previously. The experience in this procedure is an advantage in our clinical practice.