What is the term for an abnormal mass of proliferating cells?

The term for an abnormal mass of proliferating cells is neoplasm. This term encompasses any new and abnormal growth of tissue, which can be benign or malignant. Neoplasms arise when normal regulatory mechanisms that control cell division and proliferation malfunction, leading to uncontrolled cell growth. This can occur in various tissues throughout the body.

In contrast, malignancy refers specifically to a neoplasm that is cancerous, indicating that it possesses the potential to invade and spread to other parts of the body. A cyst is a closed sac-like structure that can be filled with fluid or other material but does not necessarily involve proliferating cells in the same context as neoplasms. Fibromas are benign tumors made up of fibrous or connective tissue, which are a type of neoplasm, but they are more specific compared to the broader category defined by the term neoplasm. Therefore, neoplasm is the most appropriate and encompassing term for an abnormal mass of proliferating cells.