Hemangiosarcoma in Dogs – Whole Dog Journal

While a analysis of canine most cancers isn’t good, there are few varieties worse than hemangiosarcoma (HSA). Like all most cancers diagnoses, it’s scary, surprising, and devastating. Often with this type of most cancers there are not any warning indicators or signs; it may well hit arduous and quick and there could also be little time to make selections, a lot much less analysis remedy choices. 

HSA is a extremely aggressive most cancers of blood vessel cells that develops virtually solely in canines. While the dermal kind can typically be efficiently handled, the visceral kind can out of the blue turn into evident with vital, and sometimes deadly, signs. 

Hemangiomas are benign clusters of blood vessels on or beneath the pores and skin, such because the purple birthmarks that happen on infants; sarcomas are uncommon cancers that develop within the bones and smooth tissues, together with the blood vessels. Hemangiosarcoma refers to a extremely malignant illness that develops within the endothelial cells that line the floor membrane of blood vessels after which invades the blood vessels themselves. Because hemangiosarcoma impacts blood vessels, it may well develop in virtually any organ, with the spleen being the most typical anatomic location (40 to 50% of instances). 

HSA tumors affecting the atrium and the auricle of the guts have been initially considered a results of metastasis however at the moment are acknowledged as major tumor places comprising anyplace from 10 to 25% of instances; HSAs are the most typical cardiac tumor present in canine. In canine with splenic HSA, 25% may even have a heart-based HSA. 

The dermal type of the illness contains about 13 to 15% of the instances. Less widespread websites embrace liver, tongue, kidney, bladder, lung, muscle, and bone.

It is estimated that HSA accounts for five to 7% of all canine cancers. Any age or breed can develop the illness. It often happens in bigger breed middle-aged and older canine (ages eight to 12 years), although it has been reported in canine below one yr of age. While historically there was no intercourse predilection, latest experiences are beginning to present a slight improve in prevalence in males.


HSA is classed into three varieties primarily based on anatomical location: dermal, hypodermal/subcutaneous, and visceral. 

The dermal (cutaneous) type of HSA develops on the pores and skin in areas which have minimal or no fur, showing as black or reddish growths (may be singular or a number of plenty) anyplace on the physique, with the stomach, rear legs, and prepuce the most typical websites. 

In most instances, the most cancers doesn’t unfold to the dermis tissue and may be handled (and doubtlessly cured) with surgical elimination. Because of the malignant nature of the illness, nevertheless, it may well unfold internally, which happens in about one third of instances; early analysis and immediate remedy is important. 

This type of HSA has a predilection for canine with mild or non-pigmented pores and skin, sparse coats, and areas of white fur, and has been linked to extreme publicity to the solar. Thus, canine with brief white fur, resembling Dalmatians, are predisposed to creating this sort. It is believed that limiting solar publicity in canine with skinny fur and pale pores and skin might help to stop this type of the illness (there isn’t any identified preventive for different forms of HSA).

The hypodermal (slightly below the highest layer of pores and skin) type of HSA is extra aggressive and invasive than the dermal kind. This kind is characterised by darkish purple to black growths slightly below the traditional overlying pores and skin; a smooth or agency mass could also be palpable (as a consequence of bleeding), and ulceration is widespread. Local management is difficult, because the illness could also be intensive; greater than 60% of those instances unfold internally. 

Visceral (inside) hemangiosarcoma impacts the inner organs, primarily the spleen and coronary heart. It is an invasive and quickly spreading malignancy, typically life-threatening because the tumors can break open and bleed – typically with out warning.


Large breed canine look like at an elevated threat, however particularly Box-ers, Bully-type breeds, Dobermans, English Setters, Flat-Coated Retrievers, German Shepherds, Golden Retrievers, Great Danes, Labrador Retrievers, Poodles, Portuguese Water Dogs, Skye Terriers, and Whippets. The dermal kind is overrepresented in Basset Hounds, Dalmatians, and Whippets and in canine middle-aged (four years) or older.

SIDEBAR: Making the Most Out of the Time You Have


The reason for HSA is unknown, however the breed affiliation suggests a genetic predisposition. The dermal kind is considered related to extra publicity to daylight as it’s typically present in lightly-pigmented and/or thin-coated canine. It has additionally been hypothesized that native irradiation could also be contributing issue. Exposure to sure chemical substances might also contribute to the event of the illness; although HSA in people is extraordinarily uncommon, publicity to vinyl chloride has been implicated. 


HSA tends to progress slowly at first, often with out signs and with out ache. As a outcome, a canine’s physique can tolerate the illness till it reaches a vital stage. Symptoms could seem for less than a restricted length and can rely on the kind of HSA and the precise location within the physique (see above for dermal kind). 

Internal HSAs – each the hypodermal and visceral types – could produce any mixture of signs from basic indicators of sickness resembling lethargy, despair, dementia, inappetence, weight reduction, constipation/uncommon bowel actions, lameness, and decreased stamina, to extra acute signs of fainting or weak point, lack of coordination, partial paralysis, intermittent collapse, seizures, stomach swelling, nosebleeds, coughing, and elevated panting. 

These malignancies are vascular by nature and develop their very own blood provide; nevertheless, the blood vessels are fashioned with mutated cells, and so they ultimately leak blood into surrounding areas. This gradual, power bleeding in small quantities could cause refined transient signs with the canine recovering as new blood cells are produced. Eventually the tumors will rupture, leading to a considerable hemorrhage with vital and apparent signs generally involving problem respiratory, elevated coronary heart and respiratory charges, pale mucous membranes, and collapse as a consequence of hemorrhagic/hypotensive shock requiring emergency veterinary care.


If HSA is suspected, your veterinarian will carry out an intensive bodily examination, noting particularly any of the signs listed above. At occasions, stomach tumors may be massive sufficient that they’re felt when palpated. Various assessments will probably be carried out, resembling an entire blood cell depend (CBC), serum biochemistry profile, urinalysis, and coagulation profile. In canine with HSA, abnormalities famous within the blood panel could embrace anemia, purple blood cell fragmentation, low platelet depend, and excessive variety of neutrophils (the first white blood cells that reply to bacterial an infection). 

The coagulation profile will decide if there are clotting abnormalities suggestive of disseminated intravascular coagulation (DIC), which is current in about half of the canine with visceral HSA. DIC is characterised by the event of small blood clots that block the blood vessels; this depletes the platelets and clotting compounds wanted to manage bleeding, which in flip could cause extreme bleeding. Heart arrhythmias are generally related to cardiac and splenic HSAs; accordingly, an electrocardiogram could also be advisable.

Diagnostic imaging utilizing radiographs or ultrasound are helpful strategies for finding, figuring out, and characterizing plenty within the stomach and cardiac areas in addition to offering doable proof of free fluid or blood. When a mass on the spleen is detected, it will not be doable to find out if the mass is malignant previous to elimination. 

A wonderful needle aspirate could also be used to take a tissue or fluid biopsy; evaluation of samples taken instantly from the tumor (or from a surgically eliminated tumor) gives essentially the most conclusive technique for making a analysis. This process, nevertheless, just isn’t with out threat: not solely does it have the potential to unfold malignant cells through the course of, it may well additionally set off bleeding of the delicate tumors. 

Imaging may assess the extent of the malignancy (staging) and decide whether or not metastasis has occurred. This may be difficult as a result of there could also be a number of tumors and/or the first tumor web site could also be tough to find out. 

A latest examine by Carloni, et al, printed within the ACVIM Journal of Veterinary Medicine (“Prevalence, distribution, and clinical characteristics of hemangiosarcoma-associated skeletal muscle metastases in 61 dogs: A whole body computed tomographic study,” Volume 33, Issue 2, March/April 2019, Pages 812-819) discovered that scientific examination and conventional diagnostic imaging modalities missed the presence of skeletal muscle metastases. The authors suggest entire physique computed tomography (CT) scans for correct evaluation and detection of metastasis to lungs, muscle, and different websites.

The visceral type of HSA could be very aggressive and grows quickly with native infiltration occurring early in the midst of this illness. The probability that it has unfold from the first tumor by the point of analysis could be very excessive, with about 80% of instances with metastasis upon preliminary presentation. The liver and lungs are widespread websites of metastasis, however the illness can unfold to any location within the physique as a consequence of its connection to the blood vessels. 

Because the signs related to HSA may be refined and non-specific, many instances are usually not identified till a ruptured tumor leads to catastrophic hemorrhage. While dermal HSA tends to have a decrease metastatic charge and has the potential to be cured, it is crucial {that a} complete evaluation even be accomplished in these instances as a result of this kind can nonetheless metastasize.


Clinical staging relies on the outcomes of the assorted diagnostic assessments carried out and might present a basis from which to discover and make remedy selections. Two totally different three-stage classification techniques are historically used for HSA.

Visceral HSA

  • Stage I: Localized tumor; no different tumors seen in imaging or at time of surgical procedure.
  • Stage II: Ruptured tumor confined to the first web site, with or with out metastasis current close to the positioning of the first tumor.
  • Stage III: Ruptured major tumor with invasion into adjoining constructions plus native or distant metastasis.

Dermal / Subcutaneous HSA

  • Stage I: Primary tumor confined to the dermis.
  • Stage II: Primary tumor involving the hypodermis with or with out dermal involvement.
  • Stage III: Primary tumor with underlying muscular involvement.


Because canine HSA tends to develop undetected till it has reached a sophisticated stage, the illness is usually immune to most types of remedy. The modalities of surgical procedure, chemotherapy, and radiotherapy can doubtlessly have some impact.

Surgery Surgery is often the first choice for remedy for all instances of HSA. 

For the dermal kind, it could be the one remedy that’s vital. Sunlight-induced and superficial dermal HSAs are typically thought-about cured following surgical procedure; nevertheless, new tumors can develop elsewhere on the physique unbiased of a earlier prevalence. It is suggested that canine identified with this type of pores and skin most cancers ought to keep away from as a lot solar publicity as doable. Dermal and subcutaneous HSA surgical procedure websites may be fairly intensive because of the necessity of eradicating all affected tissues.

For visceral types of the illness, surgical procedure is often advisable for all places besides these involving the guts. Cardiac surgical procedure is inherently tough, however vascular tumors are much more difficult. Depending on the dimensions and involvement, atrial tumors could also be thought-about for excision. Because HSA is related to life-threatening hemorrhage and a dismal prognosis, the tough choice of whether or not to pursue emergency surgical procedure should typically be made rapidly on the time of analysis. 

For canine with splenic plenty, elimination of the spleen (splenectomy) is advisable, despite the fact that it will not be identified prematurely if the tumor is benign or malignant. It is estimated that roughly 50% of splenic tumors are benign, however even when they’re non-cancerous, the tumors may be harmful as a result of the spleen itself could be very vascular and might rupture and trigger substantial and critical bleeding. Removal of the spleen thus turns into each a diagnostic (by offering tissue for biopsy) and a therapeutic process. During the process, your entire stomach cavity will likely be examined for proof of metastasis and extra tumors with samples of any suspicious tissue taken for biopsy.

If there may be time earlier than the surgical procedure, it may well assist to have a choice made and plan in place for what you need accomplished, relying upon the findings made through the process. 

While surgical procedure could also be the best choice out there and supply the best likelihood of accelerating survival time, there are dangers and considerations. Due to the inherent nature of the illness, there’s a vital threat for extreme hemorrhage through the surgical process. 

Dogs presenting with emergency HSA could already be compromised; stabilization previous to surgical procedure often entails fluid remedy and/or blood transfusions and intensive care monitoring. Cardiac arrhythmias can happen post-surgery and, whereas most occurrences resolve inside 24 to 48 hours, some could require remedy. 

Removal of the spleen in deep-chested canine could create more room within the stomach cavity; consequently the canine could also be extra vulnerable to gastric torsion and gastropexy (abdomen tacking) could also be warranted on the time of surgical procedure.

Chemotherapy. Given the propensity for HSA to metastasize, chemotherapy is usually advisable as an adjunct remedy to surgical procedure, particularly in instances of incomplete surgical elimination, or as a major remedy for heart-based HSAs (as surgical procedure within the cardiac space may be very tough). 

There are a number of chemotherapy protocols used, consisting of both a single agent or a mixture of medication; doxorubicin (Adriamycin), vincristine, piroxicam, cyclophosphamide, and methotrexate are the most typical ones. Doxorubicin seems to scale back the gravity of the illness, but it doesn’t essentially prolong the survival time past that of different protocols. 

Metronomic chemotherapy (a relentless low dose of chemotherapy given at residence in oral kind) is being studied as an strategy that not solely reduces the possibilities of uncomfortable side effects however helps management the unfold of illness and thereby improve survival time. Since HSA just isn’t curable, the intention of chemotherapy remedy is to gradual the most cancers development whereas offering high quality of life. 

Radiotherapy. Radiotherapy (RT) has restricted use in remedy of HSA due to the place the illness types within the physique (websites have a tendency to not be conducive to receiving radiotherapy) and the extraordinarily excessive charge of metastasis. It could also be thought-about as a remedy choice for dermal types the place surgical elimination from exterior surfaces didn’t obtain clear margins, as an adjunct to chemotherapy, and for instances with localized Stage II or Stage III illness. 

As a palliative remedy, RT may be helpful in lowering ache and probably extending survival time. Exploration of radiotherapy as a remedy choice is continuous, nevertheless, and a few latest – albeit small – research have demonstrated that RT can present scientific advantages to canine with HSA.

SIDEBAR: You can’t help it: Reconsidering past decisions after a devastating diagnosis


I’m-Yunity and Yunnan Baiyao are two different therapeutics which were documented as having some success in treating HSA. While the analysis could also be restricted and within the early levels (research are persevering with), veterinary oncologists are incorporating these modalities into their remedy protocols.

I’m-Yunit. This is a poly-saccharopeptide (PSP) compound from the Coriolus versicolor mushroom, generally often known as the Yunzhi or turkey tail mushroom. It has been used for over two millennia in conventional Chinese drugs; Western researchers have lately begun exploring this mushroom as a doable anti-cancer agent to be used in people and canines. It has been demonstrated to have antitumor exercise in tissue tradition research and might increase the physique’s personal cancer-fighting talents by bettering the perform of the immune system. 

In 2012, a small (15 canine) scientific trial on the University of Pennsylvania demonstrated the efficacy of I’m-Yunity mushroom dietary supplements in canine with most cancers. This double-blind randomized multidose pilot examine featured a high-dose of PSP, which considerably delayed the development of metastasis and elevated the reported survival occasions for canine hemangiosarcoma. 

The knowledge counsel that PSP, as a single agent, may provide vital enhancements in morbidity and mortality. For extra data, see “Single Agent Polysaccharopeptide Delays Metastases and Improves Survival in Naturally Occurring Hemangiosarcoma,” in Evidence-Based Complementary and Alternative Medicine, Volume 2012.

Yunnan Baiyao. Yunnan Baiyao can also be a Chinese natural drugs and is thought for its hemostatic (stops bleeding) and wound-healing properties. It is a protected Chinese conventional drugs and the precise system is a commerce secret, however labelling does establish its major parts. 

Yunnan Baiyao is often utilized in veterinary drugs to manage bleeding in canine by bettering clotting and platelet perform and veterinary oncologists are prescribing it to manage or cease bleeding from cancerous vessels. 

In laboratory experiments, Yunnan Baiyao has been proven to kill HSA cells. Yunnan Baiyao seems to be of profit to canine with HSA, however documentation on efficacy and uncomfortable side effects just isn’t but out there; scientific trials are nonetheless being carried out.

SIDEBAR: On the Horizon: Hemangiosarcoma Studies


HSA is a formidable illness, particularly when in comparison with most different canine cancers. As with any type of most cancers, statistics are offered as basic pointers and don’t signify how a person canine will reply to remedy.

The long-term prognosis for canine with HSA is dismal, even when the illness is found at its early levels. For canine who’re receiving remedy, nevertheless, their high quality of life often stays good to wonderful. Even because the illness progresses, it doesn’t seem to trigger a lot ache; as a substitute, canine could expertise a return or improve of signs resembling bleeding, anemia, or weak point. 

Overall, 6 to 13% of canine with HSA who’re handled with surgical procedure alone will likely be alive one yr publish analysis; of these handled with surgical procedure and chemotherapy, the one-year survival charge will increase to 12 to 20%. 

  • Survival time for canine with dermal HSA that can not be cured by remedy varies vastly and relies on such elements as location and stage. In instances the place the dermal lesions invade the sub-cutaneous tissues, the survival occasions fall within the vary of 5 to 10 months.
  • The common survival time for canine with hypodermal HSA is six months.
  • Without remedy, most canine identified with HSA of the inner organs will die inside one to 2 weeks of analysis, though some can survive for a number of months and others solely a day.
  • The prognosis for sufferers with splenic HSA handled with solely surgical procedure ranges from one to 3 months, whereas these handled with surgical procedure and chemotherapy have an improved prognosis vary of 4 to eight months. However, if intensive metastasis is current on the time of surgical procedure, survival time is just about two months when adopted with chemotherapy. 
  • Clinical stage tends to be strongly related to the prognosis for canine with splenic hemangiosarcoma.
  • The prognosis declines for canine with splenic tumors that rupture; survival time tends to be shorter and unpredictable.
  • Dogs with evident metastasis at analysis and who don’t bear surgical procedure could reply to chemotherapy, which might present a protracted high quality of life compared with canine who are usually not handled in any respect. 
  • The prognosis for canine with tumors that contain the guts, liver, and/or different inside organs is worse than for these with splenic tumors.
  • Dogs with Disseminated Intravascular Coagulation (DIC) seem to have shorter survival occasions than canine with out the situation.
  • Unfortunately, virtually all canine with HSA will succumb to the illness from tumor rupture or metastasis to the organs.


HSA impacts hundreds of canine yearly, however investigation into it has been restricted, primarily as a result of it’s virtually solely a canine illness. Most different forms of canine cancers happen in people as properly and consequently have a better impetus for analysis. 

It has been greater than 40 years since chemotherapy was added to the usual of take care of the remedy of HSA. While there was little enchancment within the prognosis for canine since then, latest research present promise for the event of recent screening strategies and early detection, which is able to enable for remedy to start sooner and, we hope, a greater consequence. See “On the Horizon: Hemangiosarcoma Studies” on the subsequent web page for extra details about the most recent analysis on this devastating illness. 

Source link

Leave a Reply