Clinical epidemiological analysis of 2 403 cases of lung cancer

Abstract

Objective To understand preliminaryly the epidemiological trend of lung cancer in recent years by retrospective analysis of 2 403 cases of lung cancer in Zhongnan Hospital of Wuhan University from 2013 to 2017. Methods The clinical data of patients with primary bronchogenic cancer diagnosed in Zhongnan Hospital of Wuhan University from 2013 to 2017 were collected. The clinical data such as gender, age, history of tobacco and alcohol, operation, pathological type, clinical stage and epidermal growth factor receptor (EGFR) gene mutation were analyzed statistically. Results A total of 2 403 cases of lung cancer were collected, including 1 766 males and 637 females. There was no significant difference in gender ratio between male and female in five years (χ2=8.481, P=0.075). There were 2 398 cases with age information, the male-to-female ratios of lung cancer patients aged less than 40, 40-49, 50-59, 60-69, 70-79, 80 and over were 0.9∶1.0, 1.4∶1.0, 2.4∶1.0, 3.6∶1.0, 3.4∶1.0 and 3.3∶1.0 respectively, and the difference was statistically significant (χ2=59.004, P<0.001). The composition difference of adenocarcinoma was not statistically significant in five years (χ2=2.165, P=0.705). There was no statistically significant difference in the composition ratio of squamous cell carcinoma (χ2=4.788, P=0.310). Adenocarcinoma accounted for 43.15% (762/1 766) and 81.95% (522/637) of the pathological types of male and female patients respectively, and the difference was statistically significant (P<0.001). Squamous cell carcinoma accounted for 39.01% (689/1 766) and 7.28% (47/637) respectively, and the difference was statistically significant (P<0.001). The proportion of squamous cell carcinoma in smoking patients was 42.99% (583/1 356), which was significantly higher than that in non-smoking patients (14.61%, 153/1 047); the proportion of squamous cell carcinoma in drinking patients was 40.56% (277/683), which was higher than that in non-drinking patients (26.69%, 459/1 720), and the differences were statistically significant (both P<0.001). A total of 1 252 patients underwent surgery, accounting for 52.10% (1 252/2 403) of the total cases. The surgical rate of small cell carcinoma was 21.72% (48/221), and that of non-small cell carcinoma was 55.18% (1 204/2 182). In five years, the surgical rates of lung cancer patients were 55.11% (221/401), 51.53% (252/489), 58.23% (244/419), 53.18% (276/519) and 45.04% (259/575) respectively, and there was significant difference in the proportion of surgical and non-surgical patients in each year (χ2=19.553, P=0.001). A total of 483 patients were tested for EGFR mutation, the EGFR mutation rate was 58.8% (251/427) in adenocarcinoma patients and 15.6% (5/32) in squamous cell carcinoma patients. Among lung cancer patients aged less than 40, 40-49, 50-59, 60-69, 70-79, 80 and over, the proportions of adenocarcinoma were 76.74% (33/43), 62.39% (136/218), 57.73% (381/660), 47.95% (455/949), 52.22% (235/450) and 52.56% (41/78) respectively, and the difference was statistically significant (χ2=33.078, P<0.001); the proportions of squamous cell carcinoma were 9.30% (4/43), 21.56% (47/218), 28.03% (185/660), 34.14% (324/949), 32.44% (146/450) and 35.90% (28/78) respectively, and the difference was statistically significant (χ2=26.977, P<0.001). The difference of composition ratio of TNM staging was statistically significant in five years (χ2=21.003, P=0.034). Conclusion There has been no significant change of male-to-female ratio in patients with lung cancer in the past five years. With the increase of age, the male-to-female ratio increases first and then decreases. The proportion of adenocarcinoma and squamous cell carcinoma has not increased or decreased significantly in the past five years. Adenocarcinoma and squamous cell carcinoma are both common in male lung cancer patients, while the pathological type of female patients is mainly adenocarcinoma. Squamous cell carcinoma is highly prevalent in smokers and drinkers. The surgical rate of squamous cell carcinoma is higher than that of adenocarcinoma, and the surgical rate of non-small cell lung cancer is higher than that of small cell lung cancer. The EGFR mutation rate is higher in adenocarcinoma. With the increase of age, the proportion of adenocarcinoma in all pathological types tends to decrease, while that of squamous cell carcinoma tends to increase. The patients′ TNM staging has a downward trend, and the operation rate decreases slightly. Key words: Lung neoplasms; Epidemiology; Pathology