[Clinicopathological characteristics of 130 cases of lung cancer in the youth]

Trends in the incidence rate of lung cancer by histological type and gender in Sichuan, China, 1995-2015: A single-center retrospective study

BACKGROUND

In recent years, lung cancer incidence has been increasing; however the impact of different histological types of lung cancer is not yet clear.

METHODS

Trends in the lung cancer incidence rate by histological type were examined based on data of 36 658 primary lung cancer patients from West China Hospital between 1995 and 2015.

RESULTS

The most common histological type of lung cancer in our hospital was adenocarcinoma (ADC) in both genders, followed by squamous cell carcinoma (SQCC), and small cell carcinoma (SCLC), which is consistent with general worldwide trends. The proportion of young patients with SCLC showed a downward trend. In the overall population with lung cancer, the number of elderly patients with lung cancer increased significantly, while the proportion of elderly patients increased gradually. The mean age at diagnosis also increased. The number of women with ADC increased sharply in recent years, especially in young patients, and the incidence rate in women is now greater than in men.

CONCLUSION

Significant increases in the number of patients with ADC and the rate of lung cancer in women over recent years were observed, indicating that research on the pathogenesis of disease in these patients is urgent.

Comparison of clinicopathological and molecular features between young and old patients with lung cancer

Objective: To investigate whether features of lung cancer in young patients differ from those of elderly patients. Method: A retrospective analysis was made to compare clinicopathological and molecular characteristics between 272 young patients under 40 years old (young Group) with lung cancer and 167 elderly patients over 60 years old (elderly group). Results: The young group had significantly higher proportions of females, adenocarcinoma, and were well differentiated, without lymph node metastasis, and were of lower clinical stage as compared with the elderly group (P<0.05). The positive rate of ALK in the young group was significantly higher than in the elderly group (17.01% vs. 4.17%, P<0.05), but there was no significant difference between the mutation rate of EGFR and ROS1 in two groups. However, the distribution of EGFR mutation sub-types in the two groups was significantly different, with the proportion of 19del in the young group being significantly higher than that in the elderly group. Conclusions: The young patients with lung cancer have distinct features compared with elderly patients, and may have different mechanisms of tumorigenesis.