A common medical error: Lung cancer misdiagnosed as sputum negative tuberculosis

Objective: To emphasize that delay in diagnosis of lung cancer can be caused by the wrong diagnosis of tuberculosis (TB) in TB endemic countries. This is of major concern as early-diagnosis of lung cancer can increase the chance of tumor resectability and timely chemo-radiotherapy may provide better quality of life. Methods: Proven lung cancer patients, who had received anti-tubercular treatment (ATT) since onset of current symptoms, were studied retrospectively during the period of Nov-07 to Nov-08. Data-source: Patient interview and medical records. Results: Total of 14 out of 70 patients received wrong diagnosis of TB and had received ATT [male-12, female-2; mean age-58.07±6.81; Non Small Cell Lung Cancer (NSCLC)-12, Small Cell Lung Cancer (SCLC)-2], 12 were smokers with median smoking pack-years of 44(15 to 112). Pre-referral sputum Acid fast Bacilli (AFB) was done in only 3 out of these 14 patients and sputum AFB was negative in these 3 patients. ATT was started on the basis of chest X-ray finding and clinical symptoms. Mean duration of ATT taken was 4.46±3.15 months. Conclusion: Due to high TB prevalence and radiological similarities, a large number of lung cancer patients initially get wrongly treated for TB. Also, clinicians associate lung cancer with high case-fatality and start ATT without detailed investigation. Altogether, this leads to delay in diagnosis and progression of disease.