Lung to lung metastasis is seen in ?

Ans. is 'a' i.e., Adenocarcinoma of lung o Bronchoalveolar carcinoma (BAC) is a relatively unusual (5% of all lung cancer) subtype of adenocarcinoma that has a unique growth pattern that differs from adenocarcinoma. Rather than invading and destroying contiguous lung parenchyma tumor cells multiply and fill the alveolar spaces. Because of their grwoth within alveoli, BAC tumor cells from one site can aerogenously seed other pas of the same lobe or lung, or the contralateral lung. This growth pattern and tendency to seed can produce three radiographic presentation: a single nodule, multiple nodules (in single or multiple nodes), or a diffuse form with an appearance mimicking that of a lobar pneumonia. Because tumorcells fill the alveolar spaces and envelop small airways rather than destroying them, air bronchograms can be seen, unlike with other carcinomas. o it has the best prognosis of all the cell types.