Bronchioloalveolar carcinoma is a type of cancer that originates in the lung. Specifically, it arises from the alveoli, which are the small sacs of tissue present in the lung where the exchange of gas between blood and inhaled air takes place. Compared with other lung cancers, it is less strongly associated with smoking, and it is less likely to spread to other parts of the lung. Symptoms can include cough, weight loss and shortness of breath. Treatment focuses on removing the cancer.
There are many types of lung cancers, and they typically are differentiated based on the types of lung cells from which they arise. Bronchioloalveolar carcinoma represents an unregulated and abnormal growth of cells of the alveoli. Some experts consider the cancer to be a subtype of adenocarcinoma of the lung, which are cancers that arise from the glandular tissue of the lung.
Risk factors for developing bronchioloalveolar carcinoma include old age, being male and having certain types of chronic lung disease. Smoking also increases the risk for developing this type of cancer. This type of cancer, however, is less strongly associated with smoking than other types of lung cancer are.
Symptoms of having bronchioloalveolar cancer can vary. Some patients might be asymptomatic. Others might complain of coughing, shortness of breath, wheezing, pain during inhalation and coughing up blood. Systemic symptoms could include weight loss, decreased appetite and night sweats.
Diagnosing bronchioloalveolar carcinoma can be tricky because its presentation on imaging studies can mimic other pathologic conditions. On a chest X-ray, it might be mistaken for diseases such as pneumonia or pulmonary edema. If an abnormality is noted on a chest X-ray and it does not go away with time, bronchioloalveolar carcinoma might be suspected. Other imaging studies, such as a computed tomography (CT) scan of the chest can further characterize the lesion. To definitively diagnose the condition, a biopsy of the abnormal tissue should be taken, and the tissue obtained from the biopsy should be examined by a trained pathologist.
The mainstay of treatment for bronchioloalveolar carcinoma is surgery. Often, the cancer grows only in a certain area of the lung and can be removed surgically before it has the chance to spread to other areas of the lung or other parts of the body. During the surgery, both the lung tumor and the lymph nodes on the affected side of the lung are often removed. Some patients who have a certain sub-type of the cancer can respond well to chemotherapy regimens that include the agents gefinitib and erlotinib.