Hemangiosarcoma is a malignant tumor of blood vessel cells — rarer in cats than dogs. Visceral HSA (splenic, hepatic) survives 1-4 months even with treatment; cutaneous forms exceed 12 months with excision. In cats, splenic and cutaneous (skin) are most common. Cutaneous HSA, usually from UV exposure in white/light cats, has much better prognosis than internal forms. Surgery: $1,500-$4,000.
Arises from blood vessel endothelial cells. In cats: spleen/liver (visceral—most aggressive), skin (cutaneous—best prognosis), rarely heart. Cutaneous HSA strongly linked to chronic UV exposure — white cats and those with unpigmented ears, nose, eyelids at highest risk. No genetic cause identified. UV exposure drives cutaneous form in white/light cats
Visceral (splenic/hepatic): acute collapse, pale gums, rapid heart rate from internal bleeding; or chronic weight loss, weakness, poor appetite. Cutaneous: red, purple, or dark lesions on ears, nose, eyelids, sparsely haired areas—may bleed or ulcerate. Cardiac: rare in cats, causes pericardial effusion and exercise intolerance. Sudden collapse from tumor rupture is often the first sign. Collapse from internal hemorrhage is common presentation
Abdominal ultrasound ($200-$400): splenic masses, free blood. Blood panel ($150-$250): anemia, thrombocytopenia. Chest X-rays ($150-$300): lung metastasis. Fine needle aspirate ($100-$200) for cutaneous form. Histopathology of tissue confirms diagnosis. Echocardiogram ($400-$600) for suspected cardiac HSA. Ultrasound + bloodwork is the first diagnostic step
Splenic HSA: splenectomy ($1,500-$3,000) is emergency surgery when tumor ruptures. Median survival post-surgery: 1-3 months in cats. Chemotherapy (doxorubicin-based) may extend to 3-6 months. Cutaneous HSA: wide surgical excision ($800-$1,500) + sun protection—median survival exceeds 12 months. Apply SPF sunscreen to at-risk skin. Splenectomy is the immediate treatment for visceral HSA
Emergency splenectomy + staging + possible chemotherapy. Cutaneous HSA: $1,000-$2,000 for excision and follow-up.
White cats and cats with light-colored ears, nose, and eyelids are at greatest risk for cutaneous HSA from UV damage. Older cats (median age 10+ years) for visceral forms. No specific breed predisposition identified.
Cutaneous (localized): median survival 12+ months with excision. Visceral (splenic/hepatic): 1-4 months even with surgery. Cardiac: weeks to months. Metastatic disease has a poor prognosis.
Limit UV exposure for white and light-colored cats: keep indoors during peak sun hours (10am-4pm). Apply pet-safe SPF sunscreen to ears and nose. Annual vet checks to detect skin changes early.
02/04
Emergency splenectomy + diagnostics for visceral HSA.
Hemangiosarcoma is covered as cancer by most accident and illness policies. Coverage: emergency surgery, diagnostics, staging, chemotherapy. Visceral HSA often strikes as life-threatening emergency—insurance authorizes and funds immediate surgery.
If a splenic mass was identified on prior imaging before enrollment—even if considered benign—HSA-related claims may be denied as pre-existing. Cats with prior abdominal ultrasound showing splenic abnormality face this risk. Enroll before any imaging is done.
Splenic HSA often ruptures without warning, requiring immediate emergency splenectomy. Most insurers cover emergency procedures, but pre-authorization may be required. Keep your insurer's emergency number accessible—call from the vet during surgery if possible.
Some policies have per-condition or annual limits for cancer. Verify your policy's cancer limit covers emergency surgery + staging + chemotherapy ($5,000+). Low cancer limits ($2,000-$3,000) may not cover full treatment for visceral HSA.
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