Breast Hemangiopericytoma

Hemangiopericytoma is a rare, soft tissue tumor and it is even rarer for it to develop within the breast.

So rare and the good news is that it is also benign – not a cancer.

It is a soft tissue tumor that arises in the pericytes surrounding the walls of blood vessels. In that sense, this rare tumor is ‘vascular‘ occurring within blood vessels of the breast.

So pericytes above the basement membrane of a blood vessel or organ line characterize a hemangiopericytoma.

These lesions are mostly benign and occur in various locations around the body. However, breast hemangiopericytomas occur almost exclusively in women.

Diagnosis of Hemangiopericytomas

These breast tumors can occur at any age from the early twenties to the late sixties, and sometimes even later.

Hemangiopericytoma of the breast is so rare, there is still controversy as to whether or not they constitute a distinct category of breast tumor

They are difficult to evaluate and most diagnostic methods fail to produce a definitive diagnosis.

So, pathologists will tend to classify this breast lesion as an ‘anaplastic mesenchymal neoplasm’. The kinds of neoplastic cells within these tumors tend to lack specific ‘markers’ for easy identification.

There is a new list of benign breast tumors with more information here

Pericytes or Rouget cells

A pericyte or ‘Rouget’ cell is a connective tissue cell that usually occurs around blood vessels. They are also sometimes called adventitial cells or mural cells.

Pericytes are relatively ‘immature’ or undifferentiated cells, that can also form into fibroblasts, smooth muscle cells or macrophages.

Pericytes are important in the proper regulation of blood flow at the capillary level. Also pericytes frequently express smooth muscle actin (SMA) and desmin proteins.

Is there an increase in the risk of Breast Cancer?

Hemangiopericytoma is neoplastic cell growth. However, the cells are not bizarre, genetically mutated cells that are generally present in cancerous tumors.

When hemangiopericytoma occurs in the breast, the only real issue is misdiagnosis as a cystosarcoma phyllodes (phylloides’ tumor).

However, hemangiopericytomas sometimes, in very rare cases grow aggressively and metastasize to distant body sites.

Hemangiopericytoma does not bring an increase in the risk for breast cancer development either at the same site or in other areas of the breast.

However, this tumor is nonetheless, an abnormal growth, and treatment usually involves surgical removal.

How is Breast Hemangiopericytoma discovered?

The clinical presentation of breast hemangiopericytoma can vary. One typical feature of hemangiopericytoma of the breast is that it is a very slow-growing tumor.

On discovery of these types of tumor there may be a palpable lump. These lumps tend to be painless, firm and not attached to the skin.

Breast hemangiopericytomas tend to be round or oval in shape, well-circumscribed and often of a pinky-red color. The size of the tumors can be quite variable, ranging from about 1.5 cm all the way up to 19 cm in some cases.

Hemangiopericytomas generally do not contain microcalcifications. On the whole, specialists describe the profile of these tumors on a mammogram as ‘non-specific’.

Breast hemangiopericytomas tend to be somewhat radiopaque (somewhat dense, blocking light) with smooth, well-circumscribed borders. However, in some cases the borders might be less well-defined.

Ultrasound imaging of breast hemangiopericytomas will tend to show a well-circumscribed, hypoechoic solid mass, usually with a homogeneous distribution of internal echoes and posterior enhancement.

Sometimes a mammogram will be able to identify large veins surrounding the lesion. This is a useful clue as to the ‘vascular’ nature of the tumor.

Histological features characteristic of hemangiopericytoma of the breast

Reticulin staining often enhances the microscopic aspects of hemangiopericytomas.

Typical histological features of breast hemangiopericytoma include multiple layers of spindle-shaped neoplastic cells surrounding thin-walled blood vessels.

Normal endothelial cells tend to line these blood vessels, which often appear in ‘stag-horn’ shapes.

Tumor cells grow outside the capillaries and preserve the basement membrane. Sometimes medics use an electron microscope to help diagnose breast hemangiopericytoma.

This may then also reveal:-

myofibrils
basal laminae
pinocytic granules
elongated cytoplasmic processes
sparse cellular organelles.

Histological features suggesting a more malignant presentation of breast hemangiopericytoma

Hemangiopericytomas, including breast hemangiopericytomas, are generally benign, but certain histological features tend to be associated with a more aggressive, potentially metastasizing form of the disease.

These may include:-

increased cellular density
cytological pleomorphism (such as multiple irregular vascular luminal formations)
focal calcification
hemorrhage
necrosis
an increase in the number of mitoses
perivascular lamellar growth of atypical mesenchymal cells with vimentin-positive cytoplasm.

However, specialists generally agree that hemangiopericytoma develops as a primary breast lesion (and not as metastasis of a tumor somewhere else).

These breast tumors will almost always behave as a benign tumor, irrespective of the histological features.

Treatment for hemangiopericytoma of the breast

The main treatment for breast hemangiopericytomas is by a wide local excision and careful clinical follow-up.

Generally speaking, if the lesion is larger, there is a higher probability of potential malignancy, in which case your doctor may recommend a mastectomy.

Lymph node dissection is generally not felt to be necessary. Attempts have been made at incorporating chemotherapy and radiotherapy with inconclusive results.

Studies estimate the recurrence rate of breast hemangiopericytoma at between 25% and 50%, but there are no conclusive reports of morbidity directly associated with the disease.

Here are a few very helpful Q&A’s

What are the symptoms?

It depends on the location in the body, but symptoms include:-

sweating
a severe cough
persistent chest pain
headaches
difficulty breathing

However, most of these tumors are painless masses, often without any symptoms.

What are the hemangiopericytoma treatments?

Someone on the internet wrote

“Minimally invasive therapy, radiotherapy, radiation therapy and chemotherapy”,

but I think that’s only for brain tumors. For the breast, start with surgical removal alone, and wait to see if it recurs would be my suggestion.

What are hemangiopericytoma diagnosis?

A biopsy can provide a definite diagnosis. Also useful in the diagnosis process are imaging scans such as MRI or CT scan.

What about the hemangiopericytoma prognosis?

Some doctors say that a patient’s prognosis varies depending on the stage, location, and size of the tumor. I simply say, excellent prognosis.

What is the hemangiopericytoma survival rate?

If you read the internet, you might stumble accidentally into writings about when the tumor is in the brain, cerebellum or brainstem.

Those are completely different. Ignore that.

The breast hemangiopericytoma has an excellent prognosis.

References

Arias-Stella J Jr, Rosen PP. (1988) Hemangiopericytoma of the breast. Mod Pathol 1:98-103 https://www.ncbi.nlm.nih.gov/pubmed/3237697
Díaz-Flores L, Gutiérrez R, Varela H, Rancel N, Valladares F (1991). Microvascular pericytes: a review of their morphological and functional characteristics. Histol. Histopathol. 6 (2): 269–86. https://www.ncbi.nlm.nih.gov/pubmed/1802127
Kanazawa N, Ono A, Nitou G, Ueno E, Fujiwara M, Kamma H, Izumiya N, Fukao K. (1999) Primary malignant hemangiopericytoma of the breast: Report of a case. Surgery Today, Volume 29, Number 9 .(September, 1999). Pages 939-944 https://www.ncbi.nlm.nih.gov/pubmed/10489142
McMaster MJ, Soule EH, Ivins JC. (1975) Hemangiopericytoma: a clinicopathologic study and long-term follow up of 60 patients. Cancer 36:2232-2244. https://www.ncbi.nlm.nih.gov/pubmed/1203874
Meoli FG, Kopitnik NL. (1991) Hemangiopericytoma of the breast. Journal of the American Osteopathic Association, Vol 91, Issue 6, 606-606. https://www.ncbi.nlm.nih.gov/pubmed/1874657
Stout AP, Murray MR. (1942) Hemangiopericytoma: a vasculartumor featuring Zimmermann’s pericytes. Ann Surg 116:26- 33
Tang Q, Wang Z, Xu H: (2008) Hemangiopericytoma of the Breast: A Case Report. Breast Care 2008;3:431-433 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2931033/
Tavassoli FA, Weiss S. (1981) Hemangiopericytoma of the breast. Am J Surg Pathol 19815:745-752 https://www.ncbi.nlm.nih.gov/pubmed/6278973
Van Kints MJ, Tjon A Tham RTO, Klinkhamer JJM, Van den Bosch HCM. (1994) Hemangiopericytoma of the Breast: Mammographic and Sonographic Findings. American Journal of Roentgenology, 163 (July 1994) p. 61-63.