Accuracy of bronchial washing cytology before and after biopsy for lung cancer diagnosis

Bronchoscopic methods including: biopsy, bronchial washing and bronchial lavage have different rates of accuracy. Routine use of bronchial cytology as a simple method for diagnosis of lung cancer diagnosis is controversial. This study was performed to compare the diagnostic value of bronchial washing in lung cancer before and after biopsy. Patients with clinical and radiographic signs of lung cancer were included in this study, from January 2000 to July 2002, 1050 patients referred to Endoscopic ward of Imam khomaini hospital (Tehran) and underwent bronchoscopy. Lung cancer was demonstrated in 80 patients. Biopsy was our gold standard for diagnosis of lung malignant tumor in this study. Bronchial washing specimens before and after biopsy and biopsy specimens were studied by an expert pathologist and the pathologic reports were collected. Data were analyzed and sensitivity of bronchial washing cytology was estimated. According to the results of this study 55 patients with confirmed diagnosis of lung cancer had negative cytology indicating the sensitivity of cytology of bronchial washing to be 31.25 percent. Bronchial washing cytology was positive both before and after biopsy in 20 patients but positive tests were obtaind in 3 patients only before and in 2 only after biopsy. In general, the sensitivities of bronchial washing cytology before and after biopsy were 28.5% and 27.5% respectively which were compatible in 95.6%of caces. According to the result of this study bronchial washing cytology is not recommended as a routine procedure for diagnosis of lung cancer but if biopsy is contraindicated this procedure may be helpful.