The Tuberculosis-Cancer Conundrum – Experience of 1000 patients at a tertiary cancer centre

<bold>Background:</bold> Immunosuppression due to cancer (CA) therapies predisposes patients to various infections, with Tuberculosis (TB) presenting the most challenge due to overlapping symptoms, radiology mimics, drug interactions & interruptions in therapy. <bold>Objectives:</bold> To study the profile and outcomes of patients (pts) with TB & CA in a tertiary care oncology institute <bold>Methods:</bold> Retrospective audit of pts treated at our ‘TB -Cancer clinic’ from 2017-2019 <bold>Results:</bold> 1000 patients with TB were seen in clinic. Mean age was 46 years. 56% were males & Mean BMI was 21.2kg/m^2. Diabetes mellitus was seen in 15.7% pts, HIV in 1.2% pts. TB masquerading as CA with no underlying CA was seen in 304 patients (30.4%) which were excluded. In the TB with cancer ("TBC") cohort of 696 pts; 414 (60%) had pulmonary TB. Extra-pulmonary & disseminated TB was seen in 30% & 10% respectively. In TBC cohort, TB diagnosis was established by microbiology in 55%, histopathology in 28% & clinicoradiology in 17% pts. Majority of these pts had drug sensitive TB (89%), while drug resistance (DR) was detected in 11% [MonoDR 3% , PolyDR 1%, MDR 6%, XDR 1%]. Most common neoplasms were from hematolymphoid (23%), head & neck (19%), gastroenterology (17%), thoracic (13%) & breast (12%). TB was diagnosed in 437pts (63%) while on CA therapy, 16% concurrently at CA diagnosis & 21% after therapy completion. Cytotoxic therapy was given in 88% of TBC cohort pts [Chemotherapy-90%, tyrosine kinase inhibitor-12%, immunotherapy-1%]. TB drug toxicity was seen in 17% pts. Adherence to TB & CA therapy was good with modifications required in 1% of pts. <bold>Conclusions:</bold> TB cancer co-occurrence is a multifaceted challenge which warrants a tailored treatment approach.