Carcinome bronchiolo-alvéolaire (CBA) : particularités et prise en charge thérapeutique

Bronchiolo-alveolar carcinoma (BAC) is a primary pulmonary adenocarcinoma (ADC) developed from the terminal respiratory unit. The restrictive definition adopted by the 1999 WHO pathological classification needs complete tumour resection to exclude any signs of histological invasion. Although IIIB-IV tumours were excluded from the strict WHO definition of BAC, the first international workshop on BAC in 2004 focussed on the need to include in the same spectrum of disease pure BAC and ADC with BAC feature (ADC-WBF). BAC and ADC-WBF affect women, non smokers and asian people more frequently than other non small cell carcinomas. Their predominant lepidic and aerogenous tumour progression frequently results in a pneumonic, multifocal or diffuse presentation and explains why death is more frequently due to bilateral pulmonary involvement than extrathoracic metastasis. The natural history is slower and prognosis better than for other ADC. Surgical resection remains the best therapeutic option for localized tumours. The high frequency of epidermal growth factor receptor (EGFR) expression on tumour cells and its gene amplification and/or mutation, as well as a particular sensitivity of this entity to EGFR tyrosine kinase inhibitors offer a new strategy for therapeutic management in patients with unresectable tumours. However, the place of chemotherapy has recently been re-evaluated.