O blastoma pulmonar é um tumor primário do pulmão, raro, de mau prognóstico e que acomete doentes mais jovens do que os portadores do carcinoma de células não pequenas do pulmão. Geralmente, são vistos sob a forma de grandes massas pulmonares, sintomáticas e com metástases para linfonodos mediastinais. Do ponto de vista anátomo-patológico, estes tumores são bifásicos, englobando na sua estrutura componentes mesenquimal e epitelial. Embora infrequente, este tipo de tumor deve fazer parte do diagnóstico diferencial das neoplasias pulmonares. Os autores apresentam um caso de blastoma pulmonar e fazem revisão da literatura.

Pulmonary blastoma is a rare primary lung tumor with poor prognosis that commonly presents at a younger age than the non-small cell lung cancer. Classicaly they are large, symptomatic tumors with lymph nodal metastasis and carry poor prognosis. Pathological examination revealed features suggesting a biphasic tumor with mesenchymal and epithelial components. Over 200 cases have been reported so far worldwide since the first description of the tumor in 1945. Authors present a case of pulmary blastoma with literature revision.

OBJECTIVE: To determine the contribution of percutaneous biopsy with core cutting needle in the diagnosis of mediastinal tumors. METHOD: Retrospective review of 22 patients with mediastinal lesions who were submitted to percutaneous core cutting needle biopsy, oriented, but not guided by computer assisted tomography of the thorax, between 1999 and 2002. RESULTS: Percutaneous biopsy with core cutting needle provided adequate material in 18/22 cases, with a total positive sample rate of 82%. In 4/22 cases, the material was insufficient to define the diagnosis (18%). Percutaneous core cutting needle biopsy established a specific histologic diagnosis in 82% of the patients: 8/22 (36%) lymphoma; 5/22 (28%) thymoma; 2/22 (11%) thymic carcinoma; 1/22 (6%) metastatic adenocarcinoma; 1/22 (6%) neuroectodermic primitive tumor; and 1/22 (6%) plasmocytoma. All the patients were submitted to a thoracic X-ray after the biopsy. No complications were found in these patients. CONCLUSION: Percutaneous core cutting needle biopsy oriented, but not guided by computer assisted tomography of the thorax, is an easy and safe procedure which can provide a precise diagnosis in most mediastinal tumors, and can prevent the exploratory thoracic surgery in inoperable or chemotherapy-treated cases.