Hemangiosarcoma in cats<\/strong> is a malignant blood vessel tumor that can affect the skin, internal organs, or heart. Symptoms vary widely but often include lethargy, pale gums, rapid breathing, and sudden collapse, especially with the visceral form. Because early signs are subtle and vague, the disease is frequently diagnosed only after a tumor ruptures. Prognosis depends heavily on location and how early treatment begins.<\/em><\/p>\n\n\n\n Hemangiosarcoma in cats (HSA) is an aggressive, malignant cancer that originates in the cells lining blood vessels. Because it arises from the vascular system, it can develop almost anywhere in the body, and in cats, it most commonly affects internal organs such as the spleen and liver, or the skin. While less prevalent in cats than in dogs, it is a serious diagnosis that requires prompt veterinary attention. According to VCA Animal Hospitals<\/a>, hemangiosarcoma accounts for fewer than 1.5\u20132% of non-blood cancers in cats. Affected cats are typically older, with research showing a mean age at diagnosis of around 10 years.<\/p>\n\n\n\n Hemangiosarcoma is a malignant neoplasm arising from endothelial cells, the cells that line blood vessels throughout the body. Because blood vessels exist in every organ and tissue, this cancer has the potential to develop in many locations. In cats, the disease presents in two main forms:<\/p>\n\n\n\n A landmark multi-institutional retrospective study published in the Journal of Veterinary Internal Medicine<\/em><\/a> (Culp et al., 2008) reviewed the records of 26 cats with visceral HSA and found that the disease was most often multifocal at the time of diagnosis, meaning it had already spread to multiple sites within the body before the cat showed obvious signs of illness.<\/p>\n\n\n\n \u201cEvery time Umi is hospitalized, it\u2019s for like four days and it costs over $5,000\u2026 Maven has helped me not only save money<\/strong> but also save his life<\/strong><\/em>\u201d <\/em><\/p>\n\n\n\n \u2605\u2605\u2605\u2605\u2605<\/p>\n\n\n\n Jessica Ortiz <\/p>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n Symptoms differ considerably depending on whether the tumor is located in the skin or inside the body.<\/p>\n\n\n\n Because visceral tumors grow silently, cats may appear normal right up until a tumor ruptures. When symptoms do appear, they are often nonspecific and easily mistaken for other conditions:<\/p>\n\n\n\n The Culp et al. (2008) study<\/a> found that 82% of cats with visceral HSA were anemic at the time of admission, and that elevated liver enzymes (AST) were present in more than half of cases, pointing to how extensively the disease had progressed before diagnosis. Metastatic lung involvement was identified in 33% of affected cats at the time of presentation.<\/p>\n\n\n\n The skin form is often easier to detect simply because it is visible. Signs include:<\/p>\n\n\n\n VCA Animal Hospitals notes<\/a> that there appears to be a higher incidence of cutaneous hemangiosarcoma in lightly pigmented animals, suggesting that sun exposure is a contributing environmental risk factor.<\/p>\n\n\n\n “Hemangiosarcoma can be especially difficult to recognize in cats because the early symptoms are often vague. Small changes in activity or resting respiratory rate may be the only clues before the disease becomes more advanced.”<\/em> – Carolina Domingues, DVM, Veterinarian at Maven Pet<\/strong><\/p>\n\n\n\n Prognosis in cats depends almost entirely on which form of the disease is present.<\/p>\n\n\n\n According to data reviewed by the Veterinary Society of Surgical Oncology (VSSO)<\/a>, the median survival time (MST) for feline visceral HSA ranges from 77 to 197 days<\/strong>, with death most commonly attributed to metastatic disease. More than three-quarters of cats have evidence of metastasis at the time of diagnosis. Treatment, typically surgery with or without chemotherapy, is mostly palliative and may extend life expectancy by a matter of weeks to months.<\/p>\n\n\n\n A particularly sobering figure from the Culp et al. study<\/a>: 71% of euthanized cats in the study were euthanized within one day of diagnosis, reflecting how advanced the disease typically is at the time it is first detected.<\/p>\n\n\n\n The skin form carries a meaningfully better prognosis. A retrospective study of 18 cats with feline cutaneous HSA, reviewed in dvm360<\/a>, found that cats treated with aggressive surgical excision had significantly longer survival times than those who received no treatment. The VSSO<\/a> reports MSTs of 283 to 912 days<\/strong> for dermal and subcutaneous HSA, a stark contrast to the visceral form. However, local recurrence remains a risk, particularly when surgical margins are incomplete.<\/p>\n\n\n\n The biological nature of this cancer makes early detection genuinely difficult, even for experienced veterinarians:<\/p>\n\n\n\n Regular biannual veterinary check-ups with bloodwork are one of the best-validated strategies for earlier detection. The Cornell Feline Health Center<\/a> recommends routine wellness exams and cancer awareness as core components of feline preventive care. Bloodwork revealing early anemia may prompt further diagnostic imaging before a crisis occurs.<\/p>\n\n\n\n Treatment decisions depend heavily on the tumor’s location, extent of spread, and the cat’s overall health.<\/p>\n\n\n\n Honest conversations with a veterinary oncologist are essential: for many cats with advanced visceral HSA, the realistic goal shifts from cure to maximizing comfort and quality of life for the time that remains.<\/p>\n\n\n\n Because hemangiosarcoma and other serious internal diseases often announce themselves through small, gradual changes long before a crisis, paying close attention to your cat’s daily patterns matters enormously. Contact your veterinarian promptly if you observe:<\/p>\n\n\n\n These signs are not exclusive to hemangiosarcoma, but any combination of them in an older cat warrants same-day or next-day veterinary evaluation.<\/p>\n\n\n\n One of the greatest challenges with hemangiosarcoma, and many other serious internal diseases, is that the window between “subtle early change” and “acute crisis” can be very short. The Maven pet health app<\/a> is designed to close that gap by providing continuous, objective data on your cat’s health patterns through the Maven pet health tracker<\/a>.<\/p>\n\n\n\n Monitor heart rate, respiratory rate, activity & rest, itch behavior.<\/strong><\/p>\n<\/div><\/div>\n\n\n\n
\n\n\n\nKey Takeaways<\/strong><\/h2>\n\n\n\n
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\n\n\n\nWhat Is Hemangiosarcoma in Cats<\/strong><\/strong>, Explained<\/strong><\/h2>\n\n\n\n
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<\/figure>\n\n\n\nHow Does <\/strong>Hemangiosarcoma Present Itself?<\/h2>\n\n\n\n
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Umi<\/strong><\/p>\n\n\n\n
\n\n\n\nWhat Are the Symptoms of Hemangiosarcoma in Cats?<\/strong><\/h2>\n\n\n\n
Visceral Hemangiosarcoma Symptoms<\/strong><\/h3>\n\n\n\n
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Cutaneous Hemangiosarcoma Symptoms<\/strong><\/h3>\n\n\n\n
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A Note on Subtlety<\/strong><\/h3>\n\n\n\n
\n\n\n\nHow Does Hemangiosarcoma Affect Life Expectancy?<\/strong><\/h2>\n\n\n\n
Visceral HSA: Poor Prognosis<\/strong><\/h3>\n\n\n\n
Cutaneous HSA: More Favorable Outlook<\/strong><\/h3>\n\n\n\n
\n\n\n\nWhy Is Hemangiosarcoma Hard to Detect Early?<\/strong><\/h2>\n\n\n\n
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\n\n\n\nWhat Treatment Options Are Available?<\/strong><\/h2>\n\n\n\n
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\n\n\n\nWhen Should You Be Concerned About Subtle Changes?<\/strong><\/h2>\n\n\n\n
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\n\n\n\nHow Maven Helps<\/strong><\/h2>\n\n\n\n
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