Retrospective comparison of clinical and histopathological features, treatment-related outcomes and survival rates in lung cancer patients under seventy years of age and over

Objective: Lung cancers are the leading cause of cancer deaths in both women and men worldwide. The aim of this study is to investigate and compare the overall survival, disease-free survival, event-free survival, progression-free survival, treatment rates, clinical, and histopathological characteristics of geriatric patients and non-geriatric patients diagnosed with lung cancer. Methods: The study included 610 patients over the age of 18, who were diagnosed with lung cancer and whose diagnosis, treatment and follow-ups were carried out in the Dokuz Eylul University (DEU) Faculty of Medicine Medical Oncology Outpatient Clinic between 2018 and 2022. Lung cancer patients with missing data were excluded from the study. Demographic, clinical, histopathological and laboratory data of the patients were analyzed retrospectively. The patients were divided into two main groups as those under 70 years of age and over. The data of the patients were evaluated separately according to stage groups. Kaplan Meier Test and Log Rank Test were used in survival analysis. Results: When patients diagnosed with lung cancer at all stages are compared; the median overall survival of patients under the age of 70 was 14.46 [95% CI (12.51-16.40)] months, while the median overall survival of patients over the age of 70 was 12.16 [95% CI (8.94-15.37)] months and found to be shorter (p=0,009). Elderly patients were found to have higher ECOG-PS and more comorbidities (p<0,001). It was determined that the group aged 70 years and under received more cisplatin-based regimens, and the group aged 70 years and above received more carboplatin-based regimens in adjuvant chemotherapy in the early and locally advanced stages and in first-line treatment in the metastatic stage (Early stage: p=0,007, locally advanced stage: p=0,026, metastatic stage p=0,038). In the metastatic phase; in first-line treatment, it was observed that the rate of receiving chemotherapy was lower in the group aged 70 and over (p=0,022), and metastatic patients under the age of 70 were hospitalized due to higher rates of treatment side effects (p=0,017). While there was no difference in overall survival between age groups in the early and locally advanced stages, overall survival was found to be longer in the group under 70 years of age in the metastatic stage (Early stage: p=0,085, locally advanced stage: p=0,314, metastatic stage p=0,049). When disease-free survival (DFS) in the early stage, event-free survival (EFS) in the locally advanced stage and progression-free survival (PFS) in the metastatic stage were examined, no difference was detected between the two age groups (p=0,187, p=0,083, p=0,404, respectively). Conclusion: In our study, overall survival was found to be longer in patients under 70 years of age. When the durations of DFS in the early stage, EFS in the locally advanced stage and PFS in the metastatic stage are examined, no difference is detected between the two age groups. This shows that both age groups benefit from the treatments at similar rates. Therefore when planning the treatment of elderly patients, age alone should not be considered. Each patient should be evaluated individually with a systematic approach. Keywords: Lung cancer, age, prognosis, lung cancer in the elderly, survival