60 year old male came with progressive shortness of breath and chest pan, Contrast enhanced CT scan showed large heterogenously enhancing lesion (arrow in first image) in the left perihilar and lower lobe region occluding the left lower lobe bronchus completely. The lesion is partially encasing the descending thoracic aorta and extending in to the left atrium through the inferior pulmonary veins (arrow in secong image and arrow head in third image) . The biopsy of the lesion revealed Small cell carcinoma of lung.
Direct intravascular, cardiac extension and spread of bronchogenic carcinoma is an uncommon event. when tumor extends to left atrium, special techniques are needed is resectrion of still to be attempted.
The cardinal imaging signs of intarvenous extension of bronchogenic carcinoma on CT or MRI is filling defect of soft tissue density within the lumen of pulmonary vein and left atrium, which is continous with the primary mass. Obliteration of superior pulmonary vein is regardes as suggesting as intrapericardial tumor extension. CT remains the standard staging investigation for lung carcinoma.