Table 1.

List of studies in which LC increases the risk of developing TB

Reference	Years	Countries	Experiment type	Sample size	LC-TB number	Time of follow-up	Contents
Aoki et al.128	1991	Japan	Retrospective	442	5	\	Five of 442 patients with LC developed active TB during LC treatment despite having latent TB.
Chen et al.132	1996	China	Retrospective	3928	31	2	Out of 3928 patients with LC, 31 individuals developed TB (tuberculosis). The risk of developing active TB was higher in patients with LC compared to the general population. Additionally, patients who developed active TB before or at the same time as their LC diagnosis experienced shorter survival times compared to those who did not develop TB (p = 0.007).
Tamura et al.185	1999	Japan	Retrospective	25a	3	\	Out of 25 patients with LC, one individual developed TB, resulting in a 1.9% incidence of active TB in patients with untreated LC.
Watanabe et al.186	1999	Japan	Retrospective	758	6	\	Out of the 758 patients with cancer, 16 individuals had combined TB. Among these patients, 6 were found to have both TB and cancer.
Remiszewski et al.133	2001	Poland	Retrospective	854	60	\	60 of 845 patients with small cell LC died from active TB.
Cicenas and Vencevicius187	2007	Lithuania	Retrospective	2218	46	\	Out of the 2,218 patients with LC, 46 individuals (2.1%) had coexisting LC and TB.
Kim et al.126	2008	Korea	Case-control	3618	9	3	The incidence of active TB was found to be 3.07 cases per 1000 person-years in patients with cancer, while it was 0.77 cases in controls. This difference was statistically significant with a p value of 0.009. Patients with cancer had an increased risk of developing TB compared to controls, with an incidence rate ratio (IRR) of 4.69 (95% CI: 1.52–14.46).
Cha et al.130	2009	Korea	Retrospective	108	36	\	Out of the patients with LC, 10 individuals (27.8%) were diagnosed with TB at the same time as the diagnosis of LC, while 26 individuals (72.2%) were diagnosed with TB after the diagnosis of LC. The median time from LC diagnosis to TB diagnosis was 4 months, with a range of 1–47 months.
Silva et al.129	2013	Portugal	Retrospective cross-sectional	24b	10	\	Out of the cases diagnosed with both TB and LC, 10 were diagnosed simultaneously, meaning they received the diagnoses at the same time. In 14 cases, TB was diagnosed before the diagnosis of LC. The median time between the diagnoses of TB and LC was 5 years, with an interquartile range of 1–30 years.
Suzuki et al.131	2016	Japan	Observational	904	9	2	During the observation period, 9 out of 904 patients with cancer (1.00%) developed TB. In all cases, the occurrence of TB disease was within 2 years of the cancer diagnosis. The cumulative incidence of TB disease at 6 months was 0.65%, at 1 year it was 1.15%, and at 2 years it was 1.38%.
Şimşek et al.188	2017	turkey	Retrospective	3101	11	\	Out of the total cases of LC and TB, 17 cases were diagnosed with both combined MTB or NTM and LC. These cases accounted for 1.2% of the total LC cases and 0.9% of the total TB cases. Among these 17 cases, in 11 of them (64.8%), MTB was identified as Mycobacterium bovis.
Cukic V.11	2017	Bosnia	Retrospective	2608	34	\	34 of 2,608 patients with LC, or 1.3%, were diagnosed with tb alone.
Tamura et al.189	2020	Japan	Retrospective	1450	7	2	Among the patients with LC, seven had active TB, 45 had previous TB, and 1,398 had neither active nor previous TB. Among the 1,398 patients without active or previous TB, 795 (57%) underwent an IGRA test, and of those, 120 (15%) were diagnosed with LTBI. This data indeed suggests that active TB is an important complication among patients with Japanese LC.
Liao et al.127	2023	China	Retrospective cohort	71793	1335		1,335 cases of TB were identified among 71,793 patients with LC. The incidence of TB increased with age, and men had a significantly higher risk of developing TB than women, with an incidence rate ratio of 1.7 (95% CI: 1.5–2.0). Patients aged 60–69 years (HR: 1.4; 95% CI: 1.1–1.8) and those ≥70 years (HR: 1.9; 95% CI: 1.5–2.4) had a higher risk of TB than those younger than 50 years. Patients with a history of pneumoconiosis and those treated with surgery and chemotherapy also had a significantly increased risk of developing TB.

^aThe sample size consisted of the number of cases in clinical records with lung cancer complicated with pulmonary tuberculosis. However, there were 2 cases of active pulmonary tuberculosis diagnosed concurrently with lung cancer, and only 1 case of active pulmonary tuberculosis was found after the diagnosis of lung cancer.

^bThe sample size consisted of the number of cases in clinical records with lung cancer complicated with pulmonary tuberculosis. However, only 10 cases of active pulmonary tuberculosis were found after the diagnosis of lung cancer, and the rest were discovered before the diagnosis of lung cancer.