What is the difference between hemangioma and hemangiosarcoma

The neoplastic cells are generally elongated or spindle-shaped and may form solid areas occupying dilated hepatic sinusoids. These neoplasms are typically locally invasive. A hemangioma has destroyed the normal hepatic parenchyma. A thrombus is present at the top of the hemangioma; high magnification shows dilated vascular channels lined by flattened endothelial cells. There is minimal atrophy of hepatic cords. Dilated vascular spaces have replaced hepatic parenchyma in this hemangioma.

Both of these tumor types arise from the same cell lines, the vascular endothelium. Hemangiosarcoma is an aggressive tumor that can spread to other organs and locations in the body. Sun exposure increases the risk for both types of tumor formation on the skin and subcutaneous tissue. The tumors often appear like red to purple blisters or bumps on the skin and are typically found in areas of the body with the least amount of fur, such as the belly, scrotum, prepuce and lower limbs for dogs and the ears and face for cats.

Tumors below the skin, often bleed or bruise easily, may be painful to the touch, and may cause your pet to feel ill. You might notice general symptoms such as a reduced appetite, lethargy, lameness, and pain.

Both tumor types appear the same to the naked eye, so additional testing is necessary to determine what type of tumor is present. These tumors are more prevalent in middle age to senior large breed dogs. These tumors can intermittently bleed, causing panting, weakness, lethargy, collapse, pale gums, abnormal heart rate or rhythm, muffled heart sounds, and reduced appetite.

Since both the benign and malignant forms appear the same, a biopsy is typically needed to make the diagnosis. Regrettably, the standard-of-care for this disease has not seen significant advancement over the past 20 or 30 years. There is presently no readily available, effective test for early diagnosis of hemangiosarcoma. Careful analysis of blood samples by experienced pathologists may hint at the presence of chronic hemorrhage and blood vessel abnormalities that are suggestive of hemangiosarcoma.

However, this method is neither sensitive nor specific to confirm the diagnosis. Non-invasive imaging methods are useful aids to diagnose the disease. In particular, ultrasound is moderately specific, but it is not sensitive, and the tumor must be large enough to be grossly visible. In addition, biopsies are required for confirmation of imaging results.

Repeated biopsies of tissues where the tumors may arise without other evidence for the presence of a tumor are of little use to provide early diagnosis, and considering the fact that there is some risk to these procedures, such an approach is practically and ethically unacceptable.

The options for therapy of canine hemangiosarcoma are limited, largely because the disease is not diagnosed until the late stages. The standard consists of surgery to shrink or remove the primary tumor, when possible, followed by intensive chemotherapy.

In some cases, surgery is not feasible, or it can be impractical or inappropriate for example, if there is evidence of extensive metastatic spread to sites beyond the primary tumor. Median survival for dogs treated with surgery alone is approximately 90 days, and that is extended to approximately days by the addition of chemotherapy using one of several protocols available.

Because the goal for chemotherapy in pet dogs is to extend life with good quality, toxicity is generally not a major issue of concern, and when it occurs it is most often managed without much difficulty. There is no other therapy that has been proven to be effective to manage or control hemangiosarcoma. As we will mention below, the cells that give rise to this disease originate in the bone marrow. We do not yet know when or why they localize to the organ where the disease will arise, but this means that prophylactic splenectomy removing the spleen to prevent the development of the disease is unlikely to have any benefit, since in the absence of a spleen, the transformed cell or cells can simply go to another organ.

Several alternative and complementary approaches diet, herbs, mystical energy, etc. This usually follows extensive publicity such as from Internet chat groups after a dog receives these treatments and survives longer than anticipated, leading proponents to advertise this as success and evidence that their approach is curative for hemangiosarcoma.

The danger of attributing curative power to treatment approaches after an anecdotal response cannot be overstated. There is no reported case where one of these therapies has been consistently successful or even as good as the standard of care after it has been tested without bias to try to replicate the anecdotal response. In fact, sometimes such treatments can actually interfere with - or increase the toxicity of chemotherapy drugs.

We know that when some tumors are caught early enough, surgery alone, surgery plus chemotherapy, and in some cases no treatment at all can lead to extended survival.

In rare instances, the behavior of the tumor itself is such that disease progression is extremely slow and dogs can survive for an extended period regardless of the therapy used. This means that a small proportion of dogs diagnosed with hemangiosarcoma will live 2, 3, 4 years and longer even without aggressive management. Therefore, it is essential for families who have dogs that are diagnosed with cancer to recognize two things.

One is that veterinarians would not willingly hold back effective therapies for any disease. Our job and our responsibility are to improve the health and well being of dogs and their families, and all of us would welcome an effective and non-toxic cure for this disease. The other is that there is no shortage of predators on the Internet and elsewhere who benefit from the desperation people feel when they know a beloved family member will probably die from a serious, incurable disease.

The unwavering support of the dog-loving community has already made a difference in our understanding of canine hemangiosarcoma. To end this article, we will highlight new information that makes us optimistic about our chances to win the battle against this disease. Here, we wish to note our gratitude for the support that our group and our collaborators have collectively received from dog clubs and owners alike, both financial and by making samples available for ongoing studies.

Development of a Test for Early Detection As we mentioned above, one way to improve our success treating hemangiosarcoma is by detecting the disease early. Previous work from our group showed there are unique patterns of protein expression that can help distinguish hemangiosarcoma cells from normal blood vessel lining cells, even within the tumor.

We also knew that most tumors shed some cells into the circulation. We reasoned, then, that we could take advantage of this to develop a test to look for tumor cells in the circulation, providing a minimally invasive, accurate diagnostic test for hemangiosarcoma.

In many ways, this is similar to the proverbial search for a needle in a haystack. The tumor cells are so infrequent that they cannot be detected in routine blood tests, nor are they easy to enrich. To accomplish our goal, we needed to use a robust technology called flow cytometry. The work was published in the July issue of the journal Experimental Hematology.

Idexx Laboratories has licensed the technology from the University of Colorado.