Stage I pure bronchioloalveolar carcinoma: recurrences, survival and comparison with adenocarcinoma of the lung

Objective: Bronchioloalveolar carcinoma (BAC) is considered a subtype of adenocarcinoma of the lung, without pleural, stromal or vascular invasion (World Health Organization (WHO) classification). Previous reports had demonstrated a better prognosis following surgery for patients affected by early stage BAC than those affected by other type of non-small cell lung cancer (NSCLC). We aim to analyse differences between stage I peripheral nodular BAC and stage I peripheral adenocarcinoma of the lung, Methods: From January 1, 1993 to December 31, 1999, 1158 patients were submitted to surgical resection for NSCLC. Out of them, 28 patients (2.4%) resulted affected by stage 1 peripheral pure BAC and 80 (6.9%) by stage I peripheral adenocarcinoma. We made a comparison between these two groups. Results: The percentage of females in BAC patients was similar to that registered in adenocarcinoma patients (21.4 vs. 17.5%). No differences were detected between smokers in BAC and adenocarcinoma patients (P = 0.331). The upper lobes were the most common sites of the primary tumour in both tumour subtypes (71.4 vs. 67.5%). Relapse of disease was less frequent in BAC than in adenocarcinoma patients (14.2 vs. 33.7%); recurrent disease developed intrathoracic with higher frequency in BAC patients (75 vs. 33.3%). Both 5-year disease-free and long-term survival were significantly higher in patients affected by BAC (81 vs. 51% and 86 vs. 71%, respectively) (P < 0.05); when analysis is performed by dividing stage IA from IB tumours, BAC patients resulted to have higher DFS (stage IA, 93 vs. 58% - P = 0.044; stage IB, 61 vs. 32.5%) and higher long-term survival (stage IA, 92 vs. 79%; stage IB, 75 vs. 56%). Conclusion: Patients with stage I pure BAC have significantly longer disease-free and overall survival than those with similar stage adenocarcinoma. Even if classified as subtype of adenocarcinoma, BAC is characterised by clinical behaviour less aggressive than similar stage adenocarcinoma. (C) 2003 Elsevier Science B.V. All rights reserved.