### instruction:
If you are a doctor, please answer the medical questions based on the patient's description.

### input:
I had a soft tissue tumor removed about a year ago from my clavicle. At the time, it was approx.2-3 cm. It did not show up on ultrasound, mri or x-ray, but could be felt. Dr. didn t think it was cancerous, testing came back k negative. It was thought to be a hystiocytoma, but was negative for beta-catnine. It has come back. Very painful, all along the collar bone,shoulder and my neck. Just recently the lymph nodes on that side have swollen. My WBC IS low3.2, my platelets are low 145, MPV is 7.4, PMN 46, Grans 1.46. I am very worried that he was wrong in thinking that it wasn t cancer. Can a hystiocytoma become cancerous? . .

### output:

Hi, Thanks for writing in. There is an entity known as malignant fibrous histiocytoma. Malignant fibrous histiocytoma (MFH), a type of sarcoma, is a malignant neoplasm of uncertain origin that arises both in soft tissue and bone. It is a malignant tumor by itself and has several subtypes. This is seen in elderly population over 50 years age and rare in young people. Since your cancer testing is negative, it is unlikely to be a malignant form of histiocytoma. You might be having Benign fibrous histiocytoma (FH) is one of the most common mesenchymal neoplasms of the skin. Several histologic variants of cutaneous FH have been described, some of which also have distinct clinical features including a propensity for local recurrence. It is important to note that rarely there might be metastasis in benign fibrous histiocytomas which contain atypical cells. Please discuss with your doctor.