Soft Tissue Cancer (Rhabdomyosarcoma) in Cats
Key takeaways
Rhabdomyosarcoma (RMS) in cats is a malignant tumor originating from the striated muscle cells (muscles normally attached to bones), occurring wherever there are striated muscle fibers.
- Common locations for RMS include the head,legs, oral cavity, heart, and bladder
- Most cases have no identifiable underlying trigger but very rare cases have been linked to injection site reactions
- Symptoms vary depending on location and may include tumors that are visible or palpable, weight loss, difficulty urinating or blood in the urine, lethargy, rapid breathing, difficulty swallowing or breathing
- Diagnosis involves physical examination, blood work, diagnostic imaging, and biopsy
- Treatment options involve tumor removal and in some cases, surgery may be combined with radiotherapy
- Prognosis varies depending on tumor location and secondary spread
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A closer look: Soft Tissue Cancer (Rhabdomyosarcoma) in Cats
A tumor is defined as a mass of abnormal cells that grow at a rapid rate. Tumors can be either benign (non cancerous) or malignant (cancerous). Benign tumors do not spread through the body however, malignant tumors can spread (metastasize) throughout the body.
Cats with a new mass, or signs associated with RMS require prompt veterinary attention, to ensure diagnosis and treatment are started early.
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Risk factors
RMS is a rare but highly aggressive tumor in cats which spreads to the lungs, liver and spleen. Complete removal of a mass before it has spread can be curative. However, many tumors are highly invasive and cannot be completely removed and carry a poor prognosis. Symptoms vary significantly depending on tumor size, location, and speed of diagnosis.
Possible causes
Potential causes of RMS include genetic and environmental factors. The exact disease mechanism is unknown. There is an association with injection site reactions in very rare cases.
Main symptoms
Symptoms vary on tumor location.
Specific symptoms based on tumor location may include:
Testing and diagnosis
Diagnosis of RMS involves:
- Biopsy or cell sampling of the mass
- Physical examination
- Blood work
- X-rays
- Ultrasound scan
Steps to Recovery
Treatment options include:
- Surgical removal of the mass
- Radiotherapy or chemotherapy after surgery in some cases
Treatment of secondary complications
- Pain relief
- Antibiotics
Complete removal of small tumors may be curative whereas incomplete removal, or tumors that have already spread internally often lead to recurrence and are fatal.
Prevention
RMS is a complex form of cancer which is not preventable. Early detection may be possible through monitoring of common injection sites.
Is Soft Tissue Cancer (Rhabdomyosarcoma) in Cats common?
RMS is a rare tumor in cats.
Typical Treatment
- Surgical removal of the mass
- Radiotherapy or chemotherapy after surgery in some cases
- Pain relief
- Antibiotics
