Disease Guide

Cutaneous Hemangiosarcoma in Dogs & Cats: Symptoms, Diagnosis & Care [2025]

Cutaneous hemangiosarcoma has a better prognosis than the visceral form; UV exposure may be a risk factor. Early wide-margin surgical excision generally yields better outcomes.

Last updated: 2026/01/05
Pethealthmap Editorial Team
Sources: ACVIM, WSAVA, National Taiwan University Veterinary Hospital

When to See a Vet

Seek Emergency Care Immediately

  • Heavy, uncontrolled bleeding from the wound within a short period
  • Mass has ruptured with significant blood loss that cannot be stopped
  • Lethargy and markedly reduced appetite

Schedule a Clinic Visit Soon (Within 24–72 Hours)

  • Red or purple skin mass that bleeds
  • Mass is growing rapidly or has an irregular shape
  • Local pain with the pet avoiding touch or frequently licking and biting the area

01What symptoms indicate something is wrong?

Common signs include red-to-purple skin lumps or recurrent bleeding; the lump may enlarge rapidly or the surface may ulcerate. Early evaluation is recommended.

  • Red or purple nodules or lumps appear on the skin
  • The lump surface ulcerates, crusts over, or bleeds easily when bumped
  • The tumour grows rapidly or has an irregular shape
  • A repeatedly scratched area continues to bleed or forms a blood crust
  • The area may be painful — your pet may avoid being touched there
  • If there is recurrent bleeding or rapid changes in the lump, seek veterinary care promptly

Seek emergency care immediately if you notice the following symptoms:

  • ⚠️ Profuse bleeding from the wound that cannot be controlled within a short time
  • ⚠️ The lump suddenly ruptures and causes heavy bleeding
  • ⚠️ Bleeding is accompanied by a marked drop in energy and appetite

02How can I assess the situation at home? Key observations and emergency criteria

Recording key information at home helps the vet quickly understand the condition and arrange the appropriate tests.

  • Take close-up and full-body photos or a short video of the lesion for reference
  • Note when the lump was first noticed and any subsequent changes in size or shape
  • Record how often scratching, bleeding, or ulceration occurs and how you managed it
  • Watch for changes in energy, activity level, appetite, and toileting habits
  • Monitor body weight and water intake regularly for any significant changes
  • If heavy bleeding occurs, apply gentle pressure with a clean gauze pad and seek veterinary care

03How will the vet diagnose this? Common diagnostic steps

The vet will typically start with a physical exam, sampling, and imaging; advanced imaging or biopsy may follow depending on the findings.

Physical examination

palpation to assess lump size and pain response

Skin sampling

scraping or fine-needle aspiration for preliminary cytology

Chest and abdominal X-rays

to evaluate for visceral metastasis or abnormal shadows

Ultrasound

to examine changes in the abdominal organs or tissues surrounding the lesion

Advanced imaging (CT or MRI) and biopsy under anaesthesia for a definitive pathological diagnosis

04What treatment and aftercare are needed? Medication, diet, and home care guide

Treatment may include local excision or systemic therapy; post-operative wound care and regular imaging follow-up are needed to monitor for recurrence or metastasis.

  • Surgical excision is a common option for local control
  • Systemic treatment (e.g. chemotherapy) requires specialist evaluation
  • Schedule regular recheck appointments and imaging follow-ups as directed by your vet
  • Home care includes wound cleaning and preventing the area from getting wet or being licked
  • Appropriate diet and supportive care aid post-operative recovery and overall health
  • Discuss a follow-up plan with an oncologist or a hospital with advanced imaging capabilities

05What should I prepare before the vet visit? Key steps to help your vet assess quickly

1
Take close-up photos, full-body photos, and a short video of the lesion for reference
2
Write down when the lump was first noticed, how it has changed, and what you have done about it
3
Note the frequency of scratching or bleeding and whether any measures were taken to stop the bleeding
4
Mention any recent changes in appetite or living environment
5
Bring any previous test reports or imaging results if available
6
When booking, note that an evaluation for a skin tumour or advanced imaging is needed

This content is for reference only and cannot replace a professional veterinary diagnosis. If your pet shows signs of illness, please seek veterinary care promptly.

Frequently Asked Questions (FAQ)