Humans When<unk> s affect humans, they are typically found in skin. They usually occur as a single lesion on the trunk or wrist. Although it is rare,<unk> s are sometimes found in the lung. It can also affect children. Other animals Mast cell tumors are known among veterinary oncologists as 'the great pretenders' because their appearance can be varied, from a wart-like nodule to a soft subcutaneous lump (similar on palpation to a benign lipoma) to an ulcerated skin mass. Most mast cell tumors are small, raised lumps on the skin. They may be hairless, ulcerated, or itchy. They are usually solitary, but in about six percent of cases, there are multiple mast cell tumors (especially in Boxers and Pugs). Manipulation of the tumor may result in redness and swelling from release of mast cell granules, also known as Darier's sign, and prolonged local hemorrhage. In rare cases, a highly malignant tumor is present, and signs may include loss of appetite, vomiting, diarrhea, and anemia. The presence of these signs usually indicates mastocytosis, which is the spread of mast cells throughout the body. Release of a large amount of histamine at one time can result in ulceration of the stomach and duodenum (present in up to 25 percent of cases) or disseminated intravascular coagulation. When metastasis does occur, it is usually to the liver, spleen, lymph nodes and bone marrow. File:Mast cell tumor side.Mast cell tumor on the side of a dog File:Mast cell tumor inner thigh.Mast cell tumor on the inner thigh of a dog File:Mast cell tumor of the toe.Mast cell tumor of the paw
Mastocytoma
Oncocytoma
Histiocytoma
Pineocytoma
Renal oncocytoma
Melanocytoma
Pleomorphic adenoma
Angiomyolipoma