The Influence of the Bronchioloalveaolar Component of an Invasive Adenocarcinoma on Survival
Philip S Hasleton, Trond-Eirik Strand, Erik H Strom, Hans Rostad. Hebrew University, Jerusalem, Israel; Cancer Registry of Norway, Oslo, Norway; Oslo University Hospital, Oslo, Norway
Background: The literature has been divided as to whether the adenocarcinoma in situ (AIS) component of an invasive adenocarcinoma has an influence on prognosis. We were able to study a cohort of Norwegian patients, who had resections for adenocarcinoma to answer this question.
Design: 137 cases with an AIS component were selected from a series of invasive adenocarcinomas. Some cases were reclassified as different tumor types and discarded. The cases were studied by one pathologist (PSH) who had no knowledge of the clinical outcome. The percentage of the AIS component was calculated on the total number of tumor sections and a mean calculated. The presence of lymphatic, vascular and pleural invasion, when present, were noted. A final diagnosis as to the predominant cell type in the tumor was recorded. Age, sex, tumor size, pTNM grade and pathology variables were adjusted for in a Cox regression analysis.
Results: 103 patients were identified with an AIS component, five cases had 'pure' AIS and two further cases had more than a 95% component. The remaining 96 cases had invasive adenocarcinoma with an AIS component. 56.3% of the patients were aged 50 - 69 years. There were 55 females and 48 males. 64% of cases were p stage I (TNM7). Correlations with age, sex, pTNM stage, side of the tumor had no significant correlations. Patients with a greater AIS component had superior survival (p = 0.019). However mucinous tumors had a worse prognosis than non-mucinous (p=0.022). As expected, patients with lymph node metastases as well as pleural invasion and lymphatic and vascular involvement had poorer survivals than those without.
Conclusions: The percentage of the AIS component plays an independent significant prognostic factor in adenocarcinomas of lung with this component. It is recommended that histopathologists routinely calculate this percentage and incorporate the information into their final report, as this is a significant factor relating to survival. It does not take long to calculate the percentage of the AIS component. This data needs an interobserver verification study. The present data is compared with that in the literature.
Tuesday, March 20, 2012 9:30 AM
Poster Session III # 316, Tuesday Morning