Bronchioloalveolar Carcinoma in Spain: A Rare and Different Form of Lung Cancer

ObjectiveTo describe a series of cases of bronchioloalveolar carcinoma (BAC) treated surgically between 1993 and 1997 in the 19 hospitals that make up the Bronchogenic Carcinoma Cooperative Group of the Spanish Society of Pulmonology and Thoracic Surgery (GCCB-S).Patients and methodsFrom a total of 2944 cases of nonsmall cell lung cancer (NSCLC), 82 (3%) were BAC. The clinical characteristics and prognosis of patients with BAC were compared with those of the remaining 2862 patients with NSCLC.ResultsThe percentage of men was lower for BAC than for other types of NSCLC (64.6% compared with 93.5%; P<.001) and BAC was associated with less comorbidity (50% vs 62%; P<.05), particularly in terms of chronic obstructive pulmonary disease (33% vs 47.2%; P<.05). Other characteristics showing significant differences were the higher frequency of BAC as a chance finding and the lower likelihood of weight loss or reduced performance status at the time of diagnosis. Classification as stage cI was significantly more common in patients with BAC (87% vs 75%; P<.001), and this difference between groups was more pronounced for stage pI (68.5% vs 47%; P<.01). Only taking into account patients classified as stage pI with complete resection of NSCLC and following exclusion of operative mortality, patients with BAC presented an overall 5-year survival of 65% (95% confidence interval [CI], 51%-79%), compared with a significantly lower survival of 53% (95% CI, 50%-56%; P<.05) in patients with other forms of NSCLC.ConclusionsIn Spain, among cases of lung cancer treated by surgery, BAC is very rare (3%) and displays clinical characteristics that are different from other forms of NSCLC. Controlling for the most basic prognostic factors (stage pI and complete resection), survival is significantly higher for BAC.

ObjetivoDescribir una serie de casos de carcinoma bronquioloalveolar (CBA) tratados quirúrgicamente por los 19 hospitales del Grupo Cooperativo de Carcinoma Broncogénico de la Sociedad Española de Neumología y Cirugía Torácica (GCCB-S) entre 1993 y 1997.Pacientes y métodosDel total de 2.944 casos de carcinoma broncogénico no microcítico (CBNM), 82 (3%) eran CBA. Se compararon las características clínicas y el pronóstico de los CBA con los de los restantes 2.862 CBNM.ResultadosLos CBA ocurren menos frecuentemente en varones (el 64,6 frente al 93,5%; p = 0,001), tienen menos comorbilidad en general (el 50 frente al 62%; p < 0,05) y enfermedad pulmonar obstructiva crónica en particular (el 33 frente al 47,2%; p < 0,05). Otras características con diferencias significativas son la mayor frecuencia de que el CBA sea un hallazgo casual y la menor probabilidad de que en el momento del diagnóstico exista historia de pérdida de peso o peor estado clínico. Por estadios clínicos, la clasificación Ic es significativamente más frecuente en los CBA (el 87 frente al 75%; p = 0,001), diferencia que se incrementa en la estadificación Ip (el 68,5 frente al 47%; p < 0,01). Considerando la población de CBNM con resección completa en estadio Ip, y una vez excluida la mortalidad operatoria, los CBA presentan una supervivencia global a los 5 años del 65% (intervalo de confianza [IC] del 95%, 51-79%), significativamente superior al resto de CBNM no CBA, en que es del 53% (IC del 95%, 50-56%) (p < 0,05).ConclusionesEn España, entre los casos de cáncer de pulmón operado, el CBA es muy infrecuente (3%) y presenta características clínicas diferentes del resto de los CBNM. Controlando con los factores pronósticos más básicos (estadio Ip y resección completa), la supervivencia del CBA es significativamente superior.