Survival of Cancer Patients with Co-Morbid Tuberculosis in Thailand

Background and objective We aimed to investigate the survival time and its related factors among cancer patients with co-morbid tuberculosis (TB) in Thailand. Methods We conducted this retro-prospective cohort study on cancer patients without co-morbid TB using the data from population-based cancer registry of Khon Kaen, TB databases from the Khon Kaen Central Hospital, and the Region 7 Office of Disease Prevention and Control from 2001 to 2015 to determine the onset of TB after cancer. The cancer patients were then followed up until 2017 to assess their survival status. The Kaplan-Meier method, log-rank test, and Cox proportional hazard regression were used to estimate cumulative survival curves, compare various survival distributions, and adjusted hazard ratios. Results Lung, head and neck, and liver cancers led to a significantly different survival time between patients with and without co-morbid TB. After adjustment, it was found that patients suffering from lung, head and neck, or liver cancer and co-morbid TB had significantly lower risk of death than those without co-morbid TB. Based on the stratified analysis, lung cancer patients with distant metastasis and co-morbid TB had 3.01-fold and 2.99-fold significantly increased risk of death compared to those without co-morbid TB. Conclusion We found that cancer patients with co-morbid TB were at lower risk of death compared with those without co-morbid TB. In addition to cancer stage, it seems that cancer comorbidity with TB could modify the risk of death for lung cancer patients.There is a need for further studies to support our findings including other related risk factors. .