What is the difference between tumor and adenoma

5 iun. The basic difference between a benign tumor and a cancer is its slower growth and lower capacity to spread. In other words adenomas are much. 1 mai with an eye toward correlating any distinct differences or similarities between carcinoid tumors and adenomas of the middle ear. 11 iul. It is important to differentiate PALG from adenoid cystic carcinoma (ACC) because of their vastly different prognosis and treatment. Diagnosis.