Adenocarcinoma of the lung usually evolves from the mucosal glands and represents about 40% of all lung cancers. It is the most common subtype to be diagnosed in people who have never smoked. Lung adenocarcinoma usually occurs in the lung periphery, and in many cases, may be found in scars or areas of chronic inflammation.
Usually single, polypoid or ulcerated mass May cause serosal puckering if muscularis propria is involved Right colon tumors tend to be polypoid and exophytic, while left colon tumors tend to be annular, encircling lesions