Abstract

Lung cancer is one of the most common types of malignancy in western nations with serious health problem, and it has become the leading cause of cancer death of males, second only to stomach cancer, in Korea. A review of the histopathology of 1363 cases (1231 patients) of lung carcinoma, diagnosed at the Keimyung University Medical center from 1987 to 1996, was performed to reclassify the type of carcinomas and to investigate the change in the distribution of histologic types of lung carcinoma according to age, sex and year. Among the 1363 cases, 132 patients underwent a surgical operation after biopsy. The diagnosis of each case was proven by histopathologic analysis of surgical specimens (13.2%) and biopsy materials (86.8%). The histologic types in our study were basically based on modified WHO classification (1982) and on new WHO classification (1999). The classification of small cell carcinoma was based on International Association for the Small Cell Lung Cancer (IASLC, 1988). Of the 1231 patients with lung carcinoma, 1012 were male and 219 were female (male to female ratio was 3.6:1). According to the analysis of age distribution, the most prevalent age group was 60~69 years in both sex as (n=516, 42.0%). Changing trends in sex distribution of lung carcinoma patients showed that the proportion of men had decreased throughout the years, whereas the proportion of women had significantly increased. Histologically, squamous cell carcinoma was the most common (n=624, 50.7%), followed by small cell carcinoma (21.1%), adenocarcinoma (18.1%), large cell undifferentiated carcinoma (2.1%), adenosquamous carcinoma (0.4%), and large cell neuroendocrine carcinoma (0.4%), in order of frequency. In men, squamous cell carcinoma was the most frequent type (55.1%). In women, adenocarcinoma was the most frequent type (39.7%). In both sexes, adenocarcinoma was the most common type in patients under the age of 40 (n=12, 41.4%), while squamous cell carcinoma proved the most frequent type in patients over the age of 40 (n=617, 51.3%). Changing trends of histologic types of lung cancer showed that the incidences of squamous cell carcinoma had significantly decreased throughout the years, whereas those of adenocarcinoma and small cell carcinoma had increased. In conclusion, the results showing increases in the percentage of female patients and in the number of cases of adenocarcinoma were noteworthy, and well correlated with other related reports.

• Keywords: Lung carcinomas;WHO classification (1999);Histopathologic features;