Relationship between weight gain and survival rate in patients with metastatic lung cancer

Lung cancer accounts for about 13% of all cancers and about 60% of patients with lung cancer also experience weight loss during treatment. There seems to be a clear correlation between the therapeutic outcomes of patients based on their weight changes during treatment. The aim of this study was to investigate the relationship between weight changes during and after treatment and the therapeutic outcomes of a patient with metastatic lung cancer.

This cohort study was performed on patients with the diagnosis of non-surgical metastatic lung cancer referred to Hematology and Oncology Clinic, Rasoul-e-Akram Hospital. Patients were divided into two groups with a weight gain of more than 5% and a weight gain of 5% and less. The information was entered into the SPSS version 21 software. In the descriptive analysis, mean and standard deviation (SD) were used. To compare quantitative variables, independent samples t-test , Mann-Whitney, chi-square or Fisher exact tests were used to compare qualitative variables and correlation test was used to determine the correlation between quantitative data. Survival curves were used to show differences in two groups of studies. A regression model was used to calculate the hazard ratio. The significance level was less than 0.05. 

Sixty patients, including 40 males (66.7%) and 20 females (33.3%) were studied. The mean age of patients was 62.22±9.00 years (43-83 years). The mean weight changes in the patients were -1.28±6.11 kg (-16 to 16kg). Forty-seven patients (78.3%) had weight gain less than 5%. There was no significant difference in overall survival (OS) and progression-free survival (PFS) according to weight gain.

Finally, the findings of the study showed that, despite the fact that PFS and OS in the weight gain group were greater than 5% of the original weight; the difference was not statistically significant.