Leiomyoma in Cats: Vet Guide 🐱🩺 2025

By Dr Duncan Houston BVSc, veterinarian & founder of Ask A Vet.

Leiomyoma refers to a benign tumor arising from smooth muscle—commonly occurring in the stomach, small or large intestine of middle-aged to older cats. Though non-cancerous and rare, they can cause blockage, bleeding, or discomfort. This guide covers:

• 🔍 What leiomyomas are and how they form
• 🧬 Risk factors and prevalence
• 🚨 Clinical signs based on location
• 🧪 Diagnostic workup
• 💉 Treatment and surgical management
• 📆 Prognosis and follow-up
• 🤝 Ask A Vet telehealth support

🔍 What Is a Leiomyoma?

A leiomyoma is a benign (non-spreading) tumor of smooth muscle tissue. In cats, these often arise from the stomach or intestinal wall, potentially causing obstruction or organ displacement :contentReference[oaicite:2]{index=2}.

🧬 Risk Factors & Prevalence

• Typically affects cats over 6 years old; no breed or sex predisposition :contentReference[oaicite:3]{index=3}.
• Benign—unlike leiomyosarcoma, which is malignant and more aggressive :contentReference[oaicite:4]{index=4}.

🚨 Clinical Signs by Location

Symptoms vary depending on tumor location:

• Stomach: Chronic or intermittent vomiting, sometimes blood-tinged; nausea and weight loss :contentReference[oaicite:5]{index=5}.
• Small intestine: Vomiting, weight loss, abdominal rumbling, gas, palpable mass :contentReference[oaicite:6]{index=6}.
• Large intestine/rectum: Straining, tenesmus, hematochezia (bright-red blood), rectal prolapse :contentReference[oaicite:7]{index=7}.
• Paraneoplastic hypoglycemia sometimes seen with large tumors :contentReference[oaicite:8]{index=8}.

🧪 Diagnostic Process

1. History & Exam: chronic GI disturbance, mass on palpation.
2. Bloodwork: CBC and chemistry often normal; hypoglycemia or anemia may occur :contentReference[oaicite:9]{index=9}.
3. Imaging: Abdominal X-rays and ultrasound reveal gut wall thickening or mass; contrast studies help localize lesions :contentReference[oaicite:10]{index=10}.
4. Endoscopy: Visualizes gastric masses; biopsies often inconclusive for deep tumors :contentReference[oaicite:11]{index=11}.
5. Surgical biopsy/resection: Required for definitive diagnosis :contentReference[oaicite:12]{index=12}.

🛠️ Treatment & Surgical Management

Surgical removal is treatment of choice:

• Complete resection of the mass often curative :contentReference[oaicite:13]{index=13}.
• Benign tumors allow narrower margins versus malignant ones.
• Surgery resolves symptoms and prevents blockages.

📆 Prognosis & Follow-Up

• Excellent long-term outcomes if completely removed :contentReference[oaicite:14]{index=14}.
• No follow-up typically needed unless pre-surgical hypoglycemia or anemia was present :contentReference[oaicite:15]{index=15}.
• Recurrence unlikely due to benign nature.

🩺 Ask A Vet Telehealth Role

Ask A Vet offers:

• 📸 Review symptoms and decide urgency for imaging or surgery.
• 💬 Help interpret imaging results and guide referral timing.
• 📆 Post-op monitoring of appetite, vomiting, incision and follow-up testing.
• 📈 Provide reassurance and guidance after surgery for recovery milestones.

✅ Key Takeaways

• Leiomyomas are benign smooth muscle tumors, most often in older cats.
• Signs include vomiting, weight loss, mass palpable, GI discomfort, and possible hypoglycemia.
• Diagnosis relies on imaging and surgical biopsy.
• Surgical removal is curative; prognosis excellent with complete excision.
• Ask A Vet telehealth supports decision-making, recovery and monitoring.

📞 Final Thoughts

Although leiomyomas are rare, they can significantly impact gut function—but surgical removal is usually curative. With Ask A Vet guidance through diagnosis, surgical planning, and recovery, your cat can get back to healthy, happy living. 😊

Need help interpreting imaging findings, deciding on surgery timing, or post-op care? Visit AskAVet.com and download the Ask A Vet app for personalized telehealth support anytime!