A hemangiopericytoma, or HPC, is a form of soft-cell sarcoma that appears in the pericyte cells of capillaries, the smallest of the blood vessels.
These growths are usually painless and can form anywhere in the body, but they most commonly appear in the lower extremities, pelvic area, head, and neck. These tumors tend to grow very slowly; some patients had the tumor for twenty years before a diagnosis was made.
However, when these tumors develop in the central nervous system, they are very aggressive and can metastasize, or spread, very quickly.
Signs & Symptoms
This tumor’s signs and symptoms depend on its location in the body. Tumors near the abdomen usually cause vomiting, nausea, diarrhea, and severe abdominal pain. Patients exhibiting these symptoms should seek medical treatment immediately to determine if the cause of these symptoms is a hemangiopericytoma or an intestinal blockage.
These tumors grow slowly in other parts of the body. In the legs or pelvis, for example, it may take some time for a noticeable mass to form, but other symptoms can include limping, pain or soreness in the pelvis or legs, or difficulty walking.
Depending on the location of the tumor, other symptoms can include sweating, a severe cough, persistent chest pain, and difficulty breathing.
Diagnosis & Treatment
Because the mass may not have many obvious symptoms, or because the growth can take some time to spread, a patient may not receive a diagnosis for years. Many patients seek treatment for other conditions, such as persistent headaches or other neurological problems, and that is often when the hemangiopericytoma is detected and diagnosed.
A biopsy can provide a definite diagnosis, and an imaging scan, such as an MRI or CAT scan, will show how much the mass has metastasized.
Surgery is the most effective form of treatment for this type of tumor. For masses in the skull, a procedure called the Endoscopic Endonasal Approach (EEA) is used. Through this process, a doctor can remove the tumor through the nasal cavity, which does not require incisions in the skull or face. Radiation and chemotherapy are other common treatment options; they can often be started after the EEA has been done.
A patient’s prognosis varies depending on the stage, location, and size of the tumor. 75 percent of patients have a 5-year survival rate, but the overall long-term prognosis is often fair to poor.