Ancillary Techniques for Early Detection of Lung Carcinoma in Sputum: An Update

Lung cancer is the most rapidly spreading cancer worldwide as well as in India.The major cause of development of such malignancy is the cigarette or bidi smoke being inhaled by the smokers as well as their family members passively, leading to predominantly squamous or the small cell variety of tumours.Lung cancer is regarded as one of the most common cancers in the world. 1 In 2012, lung cancer occurrence worldwide was approximately 1.8 million patients with an estimated mortality of 1.6 million. 1Immunohistochemistry (IHC) and fluorescence in-situ hybridisation (FISH) are molecular techniques involved in the diagnosis of particular mutations in lung cancer which would affect the therapeutic outcome of the tumour.The earliest known sputum cytology was performed in the year 1970, when it was mooted as non-invasive screening methodology for lung cancers.This review is an attempt to elucidate the role of sputum cytology to diagnose lung cancer as well as the ancilliary techniques available to improve the sensitivity and specifity of diagnosis of cancer by sputum cytology.[