Greenberg Sd

Prognostic significance of histopathologic subtype and stage in small cell lung cancer

A study of 149 light microscopic tissue slides from 147 patients with recorded initial diagnoses of small cell lung cancer (SCLC) (114 cases) and undifferentiated carcinoma (35 cases) was undertaken to test the reproducibility and prognostic impact of a new histopathologic subclassification of SCLC proposed by the Pathology Panel of the International Association for the Study of Lung Cancer (IASLC). This study was further designed to test the impact of clinical stage, age, sex, and race on survival. The tissue slides were blindly reclassified as SCLC or non-SCLC by a panel of five pathologists with no knowledge of the initial diagnosis. The SCLCs were divided into the three subtypes outlined by the IASLC pathology panel: small (classic or pure), mixed (small cell/large cell), and combined (small cell/squamous carcinoma or small cell/adenocarcinoma). Small cell lung cancer was clinically staged as local, regional, or distant. Consensus diagnosis (defined as agreement by at least three of the five pathologists) was achieved in 144 (96.6%) of the 149 cases. Of these 144 cases, 124 were reclassified as SCLC (115 [92.8%] small, five [4.0%] mixed, and four [3.2%] combined) and 20 were classified as non-SCLC. The median lengths of survival for the small, mixed, and combined subtypes were 225, 1,110, and 203 days, respectively (P = .025). Adequate staging data were available in 123 of the 124 SCLC cases. Of the 123 SCLC cases, 27 (21.9%) were local, 22 (17.9%) were regional, and 74 (60.2%) were distant stage. The median lengths of survival for the local, regional, and distant stages were 428, 251, and 111 days, respectively. This association was highly significant (P = .0001). We conclude that stage is the major determinant of survival in SCLC. Mixed subtypes had significantly longer survival times than the small or combined subtypes (P = .025). Survival times were longer for women than for men, and the survival time difference between men and women was significant (P = .0028). We found no significant differences in survival according to age or race.

Lung cancer heterogeneity: prognostic implications

Although histologic heterogeneity of lung cancer is well recognized, little information is avilable related to possible effects of this heterogeneity on prognosis. We collected 100 consecutive lung cancer cases, including 35 autopsies and 65 surgical resections, which were extensively sampled (average, ten blocks per case) and analyzed for histologic heterogeneity. Slides were randomized and classified by five pathologists using the 1981 World Health Organization (WHO) classification scheme. Five‐year follow‐up data were obtained for the surgical cases, and detailed information on staging and survival from time of diagnosis was available in 91 cases. Survival time was analyzed with respect to the patients age, sex, stage, predominant histologic pattern, and presence or absence of major heterogeneity. The latter is defined as the presence on at least one slide of a major histologic pattern different from that of the remaining slides for that case. The only statistically significant predictor of survival was tumor stage (P < 0.0001). Heterogeneous tumors appeared to have a worse survival, but this did not reach statistical significance. There was no relationship between survival and predominant histologic pattern (cell type), sex, or age.