Chemotherapy is a risk factor for occurrence of infections. Tuberculosis is a common infection in high prevalence countries. Data on incidence of tuberculosis following lung cancer chemotherapy is limited. The current study was conducted to assess the spectrum and clinical profile of pleuro-pulmonary tuberculosis following lung cancer chemotherapy at a tertiary care institute in North India.

Retrospective data analysis of newly diagnosed lung cancer patients undergoing chemotherapy over a three-and-half year period. Diagnosis of tuberculosis was made by presence of suggestive clinicoradiological features (fever, cough, pleuritic chest pain, new parenchymal infiltrates or new onset pleural effusion on chest imaging) along with demonstration of acid fast bacilli (AFB) in sputum/pleural fluid/bronchoalveolar lavage (BAL) fluid and/or growth of Mycobacterium tuberculosis on culture. For biopsy/cytology specimens, tuberculosis was diagnosed by demonstration of granulomatous inflammation with AFB.

Overall six (0.9%) of 662 lung cancer patients developed tuberculosis [four pulmonary (PTB) and two pleural (TB-PE)]. Occurrence of PTB/TB-PE and of smear-positive PTB after lung cancer chemotherapy was at a rate of 2.59 per 1000 patients/year and 1.73 per 1000 patients/year respectively, compared with national incidences of 1.85 per 1000 population/year and 0.75 per 1000 population/year respectively. Four patients had objective response to chemotherapy. Diagnosis of PTB/TB-PE was established by sputum microscopy, BAL fluid microscopy and pleural biopsy in two patients each. All patients developed tuberculosis on same side as primary tumor. All patients received standard four-drug anti-tubercular therapy (ATT). Median time interval between diagnosis of lung cancer and that of tuberculosis was 144 (56-317) days while time interval between last chemotherapy cycle and diagnosis of tuberculosis was 55 (36-182) days. Median overall survival and survival after diagnosis of tuberculosis were 312 (141-504) days and 174 (41-199) days respectively.

Occurrence of PTB/TB-PE after lung cancer chemotherapy is higher than the corresponding incidence of tuberculosis observed in the general Indian population. Overall survival of these patients is similar to lung cancer patients in general if clinical suspicion of tuberculosis is actively pursued and ATT initiated promptly following diagnosis of tuberculosis.

Singh N, Madan K, Aggarwal AN, Gupta N, Das A, Behera D. Pleuropulmonary Tuberculosis Following Chemotherapy for Lung Cancer at a Tertiary Care Center in India. J Postgrad Med Edu Res 2013;47(4):177-180.