The Importance of Sputum Cytology in the Diagnosis of Lung Cancer

Introduction: Worldwide lung cancer is the leading cause of death. The incidence of lung cancer is increasing in developing countries like Pakistan. Mortality is more than 90 % in diagnosed cases and it is directly related to the stage of disease so it is important to diagnose at an early stage. Sputum cytology is a definite way to diagnose lung cancer. It is cost effective, non-invasive, does not need any instrumentation and free of investigating complications. Objective: To study the role of sputum cytology in the diagnosis of lung cancer. Study Setting: This study was conducted at the Institute of Chest Medicine, Mayo Hospital - A tertiary care hospital affiliated with King Edward Medical University, Lahore. Study Design: Cross sectional evidence based study. Materials and Methods: Ninety seven patients (80 males, 17 females) with radiological suspicion of malignancy were included in the study. Three Consecutive morning sputum samples were collected after deep coughing. Two smears were made of each specimen and stained with Haematoxylin and Eosin and papanicolaou. All the specimens were examined by a consultant cytohistopathologist. Results: A total of 97 patients (80 males and 17 females) with clinical and radiological suspicion of lung cancer were included in the study. The patient's ages ranged between 50 - 83 years with mean age of 66.5 +/- 14.5 years. Sputum cytology was positive in 46 (45.3%) patients. Amongst males 41 (51.25%) have positive cytology, while in females 5 (29.41%) have positive sputum cytology. Out of 46 patients with positive cytology 37 (80.43%) patients (33 males and 04 females) have non small cell carcinomas while 09 (19.56%) patients (08 males and 01 female) have small cell carcinoma. Conclusion: Sputum cytology is a definite way of lung cancer detection. It is cost effective, non invasive and free of investigating complications.