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

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.

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.

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.

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.