36. Diagnóstico do cancro do pulmão: comparação da expectoração pósbroncoscopia, lavado, escovado e biópsia brônquicos

Lung cancer is one of the most important respiratory diseases. The flexible bronchoscopy (FBC) is an exam widely used in its diagnosis and staging and, in specific cases, its treatment. There are several diagnostic bronchoscopies techniques currently used. The most common are the bronchial washing (BW), brushing (BBR) and biopsy (BB).It was our aim to evaluate the diagnostic yield of these three techniques, as well as, the post-bronchoscopy sputum cytology (PBSC), at presence of a suspicious visible endoscopy lesion of lung cancer. From September of 2001 to February of 2003, 56 FBC were carried out on patients with clinical history and suggestive endoscopy injury of lung cancer (hyperaemia/infiltration/tumour). In all patients we performed BW, BBR and BB and, always if it was possible, PBSC. The patients were excluded when the 4 applied diagnostic techniques were negative for malignancy. The results had been classified as positive, negative or suspected.The diagnosis of lung cancer, through at least one of three bronchoscopies techniques or PBSC, was obtained in 44 patients (78,6%). In the total of these patients the diagnostic yield from BW was 56,8%, from BBR 79,5%, from BB 95,5%. The yield from PBSC was 28,6% (n=42). The three techniques were simultaneously positive for malignancy in 52,3% of the total, being concordant, in terms of specification of the histologic type, in 69,6%. The BBR and the BB were both positive in 22,8% (70% agreement) and BW and BB in 4,5% (100% agreement). The BBR was the only positive diagnostic technique in 4,5% of the cases and the BB in 15,9%. The BW and the PBSC were never the only positive result.Of the 7 cases where the BBR was positive for malignancy but did not allow the specification of the histology type, 5 (71, 4%) were clarified by the BB. In turn, of the 7 cases where the BB was not diagnostic of the specific type of cancer, 3 were defined by BBR (42,9%).The endoscopy aspect had been described as infiltration in 63.4% cases and the remaining as tumour. The BW was more frequently positive in presence of infiltration in comparison to tumour (64% versus 36%). It were not verified significant differences in relation to the BBR and BB.In literature there continues to exist some controversy about the diagnostic value of the BW, BBR, BB and PBSC in lung cancer. This work clearly shows that the BB is the most cost-effective technique, but the values obtained for BW and BBR were also relevant. However, it is to be stressed that neither the BW nor the PBSC constituted at any time the only positive diagnostic technique for malignancy, neither did they contributed for the clarification of the histologic type. The BBR only increased by 3,5% the total diagnostic yield