Se realizo un estudio descriptivo a una muestra constituida por 89 pacientes que acudieron al servicio de radiologia del Hospital Docente de Pinar del Rio, siendo portadores de una lesion de aspecto tumoral de torax o abdomen, ya fueran estas palpables o diagnosticadas por radiografia y/o ultrasonido con el objetivo de evaluar la utilidad de la puncion aspirativa con aguja fina, como metodo diagnostico, a estos pacientes se les realizo una puncion aspirativa con aguja fina, en el periodo comprendido entre el 1 de octubre de 1991 al 31 de mayo de 1997. Obtuvimos 90 muestras utiles, y de estas 62 resultaron verdaderos positivas (69.6%) y 7 fueron verdaderos negativos (7.8%) hubo tambien 5 falsos y 3 falsos negativos. Se hizo ademas una descripcion de la tecnica utilizada y se analizo la utilidad de las muestras (segun el metodo imagenologico empleado y las complicaciones presentadas durante el estudio. Para comprobar la eficiencia del proceder correlacionamos los resultados citologicos con los histologicos obtenidos por otros medios. Calculamos la sensibilidad, especificidad, indices predictivo positivos, negativos y fraccion positivo. Se concluyo que este proceder de gran valor diagnostico que tiene un bajo costo escasas complicaciones y es facil de realizar por un personal debidamente entrenado. DeCS: BIOPSIA CON AGUJA, NEOPLASMA ABDOMINALES/diagnostico, NEOPLASMA TORAXICAS/diagnostico. A sample of 89 patients with an abdominal or thoraxic tumor-like injury (detected on physical examination or through x-ray and/or ultrasound) was included in a descriptive study aiming to evaluate the usefulness of the needle aspiration puncture as a diagnostic method. The study was carried out in the Radiology Department at Abel Santamaria General Hospital between October 1, 1991 and May 31, 1997. The patients were submitted to a needle aspiration puncture obtaining 80 useful samples; 62 were true positive (69.6%), 7 were true negative (7.8%), 5 were false positive and 3 were false negative. A description of the technique was made. The complications during the study and the usefulness of the sample, according to the imaging method, were also analyzed. The efficacy of the procedure was proved through the correlation established between cytologic and histologic methods obtained through different means. Sensitivity, specificity, negative and positive predictive indexes and false negative fraction were estimated. It was concluded, this procedure has a great diagnostic value and significant advantages such as a low cost, and few complications. Besides, it is an easy method to be used by a properly trained staff. DeCS: BIOPSY NEEDLE, ABDOMINAL NEOPLASMS/diagnosis, THORACIC NEOPLASMS/diagnosis.