Harsha D. S1, Vishnu Sharma Moleyar2, Alka Chaitra Bhat3, Mithuneshwar Reddy Konda4, Abhishek Bali5, Abdu Rahiman Erinhikath Ummer6

Accurate staging is the cornerstone in management of lung cancer. It helps to determine the therapeutic modality and to assess prognosis. More than half of bronchogenic carcinomas have distant metastasis at the time of diagnosis. Presence of metastasis confers stage 4 for the disease. Presence of metastasis also increases patient morbidity and mortality. So the knowledge of pattern and sites of metastasis in bronchogenic carcinoma is crucial for its detection and management. Staging of bronchogenic carcinoma is one of the important indications for Positron Emission Tomography. Combined Computed tomography and PET (PET-CT) is superior to either modality alone in staging of lung cancer. It helps in identifying the site and morphology of lesion.
Aims and Objectives- 1. To determine the sites of metastases in Bronchogenic carcinoma by PETCT 2. To compare sites of metastases with the histological cell type
It was a hospital based retrospective study involving 78 patients with histologically proven bronchogenic carcinoma who underwent PETCT scan from June 2016-May 2017 in A J Institute of medical sciences, Mangalore. The sites of metastasis were noted. Brain metastasis was not included as MRI is a more sensitive tool. The sites of metastases as determined by PETCT were compared with histological cell type of bronchogenic carcinoma.
There were a total of 78 patients 61 male and 17 females. Majority of them were adenocarcinoma, followed by squamous cell carcinoma 38.5% and small cell carcinoma 9%. Majority had lymph node metastasis to supraclavicular nodes (61.53%) followed by contralateral lung (51.28%), bone metastasis (48.71%), abdominal nodes (28.21%), pleural metastasis (25.64%), adrenals (23.1%), Liver (20.51%), pericardial effusion (3.84%), spleen (2.56%). Among cases of adenocarcinoma 65.85% had metastasis to supraclavicular nodes, 56.09% had metastasis to contralateral lung, followed by bone metastasis (53.65%). Among patients with squamous cell carcinoma, majority ie, 53.33% had metastasis to contralateral lung, 40% had bone metastasis.
1. Most common site of metastasis in bronchogenic carcinoma is supraclavicular nodes. 2. Most common organ of metastasis is contralateral lung followed by bone. 3. Commonest extra nodal site of metastasis is contralateral lung for both adenocarcinoma and squamous cell carcinoma.