Lung Cancer in Dogs: Vet’s Guide to Signs, Diagnosis & Treatment 2025 🐾

By Dr. Duncan Houston BVSc

Hi—I’m Dr Duncan Houston BVSc, veterinarian and Ask A Vet founder. Lung cancer is rare in dogs (~1 % of canine cancers), but when it appears—especially in older dogs—it’s essential to act quickly. This vet‑approved guide will help you:

• Recognize common signs
• Understand how it's diagnosed and staged
• Know treatment options—surgery, chemo/radiation, palliative care
• Expect likely outcomes and recovery
• Support your dog at home

1. What Is Lung Cancer in Dogs?

It can be:

• Primary – originating in the lungs (usually bronchoalveolar carcinoma).
• Metastatic – spread from another cancer elsewhere.

Primary forms occur mostly in dogs aged 9–11, with carcinomas graded I–III based on aggressiveness.

2. Common Signs & Secondary Effects

• 🌬️ Persistent cough, sometimes with blood.
• Breathing faster or labored, exercise intolerance, lethargy, weight loss, appetite drop.
• Paraneoplastic effects like hypertrophic osteopathy—limb swelling and lameness.

3. Diagnosis & Staging

• ⬜ Chest X-rays and CT scans—detect nodules and plan surgery.
• Microscopy via needle aspirate, bronchoscopy, or biopsy—confirm type and malignancy.
• Abdomen imaging and lymph node assessment—to check for spread.
• Pathologic staging:
• Stage I: single tumor, no spread
• Stage II–III: larger or lymph node spread
• Stage IV: distant metastasis.

4. Treatment Options

4.1 Surgery (Lobectomy)

• Primary option if no metastasis—removal of affected lobe and nodes.
• Often curative for stage I, with many dogs recovering quickly.

4.2 Chemotherapy & Radiation

• Adjuvant chemo (vinorelbine, carboplatin) for metastatic or high-grade tumors.
• Stereotactic body radiation (SBRT) is used when surgery isn't feasible.

4.3 Palliative & Supportive Care

• Thoracocentesis for fluid in the chest
• Pain relief: NSAIDs, corticosteroids
• Cough suppressants, bronchodilators, and antibiotics for infections.
• Home environment: calm, easy feeding, avoid smoke/irritants.

5. Prognosis & Survival Times

• Stage I, low-grade tumors: survival often 12–16 months, sometimes >2 years.
• Advanced or metastatic: median survival 2–3 months.
• Chemo can extend survival modestly for unsuitable surgery cases.

6. Quality‑of‑Life Considerations

• Work with oncologists to weigh treatment benefits vs. stress and side effects.
• Palliative care focuses on comfort if treatment not pursued.
• Stay attuned: appetite, breathing, mobility, joy in daily life.

📌 Final Thoughts from a Vet

Though rare, lung cancer in dogs can be treated effectively—especially when caught early. Surgery offers the best chance of long-term survival for localized tumors; chemo/radiation and palliative care support quality of life when surgery isn't an option. At Ask A Vet, we provide treatment planning, symptom tracking tools, and comfort care strategies to support you and your dog through every stage. 🐾❤️