Cancer in Dogs

Cancer in Dogs: Treatment Options, Palliative Care, and How to Know When It’s Time for Euthanasia

Cancer is one of the most common health challenges facing dogs, particularly as they age. While hearing the word cancer can feel devastating, it’s important to remember that not all cancers are the same — and many can be managed for long periods with the right care.

Some cancers are highly treatable and even curable. Others are more aggressive and require a focus on comfort and quality of life. This guide will help you understand your options, from medical treatment to palliative care, and how to know when it may be time to say goodbye.

As a hospice and palliative care veterinarian practicing in New York City, my goal is always this: regardless of the path you choose, to make sure your dog’s remaining time on Earth is full of love and happiness. If your options are confusing or you aren’t sure how to know when it’s time for euthanasia, don’t hesitate to schedule a quality of life teleconsult with one of our doctors.

Treatment Options for Cancer in Dogs

The best treatment depends on the type and location of the cancer, how advanced it is, and your dog’s overall health. Common treatment approaches include:

Surgery

Pros:

• Often curative for localized tumors that haven’t spread

• Provides immediate relief if the tumor is painful or obstructive

• Typically one of the least time-intensive treatments

Cons:

• Requires anesthesia, which may be risky for senior or frail dogs

• Not possible for widespread or internal cancers

• May need follow-up treatment if the tumor recurs

Chemotherapy

Pros:

• Can slow cancer growth and extend quality time

• Most dogs tolerate chemotherapy better than humans do (minimal nausea/hair loss)

• Can improve comfort even if not curative

Cons:

• Time- and cost-intensive (multiple visits and thousands of dollars)

• Not curative in most cases — remission periods vary by cancer type

• Side effects (lethargy, appetite loss, GI upset) can occur

Radiation Therapy

Pros:

• Effective for tumors that cannot be removed surgically

• Can significantly reduce pain and slow tumor growth

Cons:

• Requires specialized equipment and anesthesia for each session

• May cause skin irritation or fatigue

• Availability may be limited

Targeted and Immunotherapy Treatments

Pros:

• Newer therapies (like Palladia for mast cell tumors) specifically target cancer cells

• Fewer side effects than traditional chemotherapy

Cons:

• Often expensive and not available for all cancer types

• Long-term success rates vary

Palliative Care for Dogs with Cancer

When treatment is no longer curative or not pursued, palliative care focuses on comfort, dignity, and happiness.

Pain Management

• NSAIDs, opioids, or gabapentin can control pain and inflammation

• Adjust medications regularly as disease progresses

Steroid Therapy 

• In some types of cancer, steroids can provide relief from inflammation, swelling, and discomfort, as well as improve appetite

Appetite and Nausea Support

• Entyce (capromorelin) stimulates appetite

• Cerenia or Zofran can relieve nausea and vomiting

Energy and Comfort

• Gentle, frequent meals and plenty of hydration

• Warm, soft bedding and easy access to food, water, and favorite spots

• Minimize stairs or provide ramps for mobility

Emotional Care

• Keep routines predictable

• Offer quiet companionship, touch, and reassurance

• Celebrate small moments: a favorite walk, a sunbeam nap, or a special treat day

How to Know When It’s Time for Euthanasia

Cancer in dogs can progress slowly or suddenly. Making an end-of-life care plan early helps ensure your decisions are thoughtful — not made in crisis.

Create an End-of-Life Care Plan

Your plan should include:

• Which treatments you would or would not pursue (e.g., surgery, chemo, steroids only)

• Whether you would hospitalize your dog in an emergency or prefer a home goodbye

• Who will be present and how you’d like the final day to unfold

You can learn more about creating an end-of-life care plan at pawsatpeace.com/time.

Keep a Daily Quality-of-Life Journal

Record your dog’s good and bad days with a simple smile or frown. Patterns will help you see changes that are easy to miss day-to-day.

Our Quality of Life Scale can help you objectively evaluate your dog’s comfort and happiness.

Develop objective criteria for euthanasia

• Persistent loss of appetite despite medication

• Uncontrolled pain or labored breathing

• Extreme weight loss or weakness

• Recurrent vomiting, diarrhea, or dehydration

• Disinterest in family, surroundings, or favorite activities

• Difficulty standing, walking, or resting comfortably

When bad days start to outnumber good ones, it’s often a sign your beloved companion is ready for peace. Giving them a gentle goodbye at home, surrounded by love, can be one of the most compassionate gifts you offer.

Final Thoughts

A cancer diagnosis can be overwhelming — but it doesn’t have to mean an immediate goodbye. Some dogs live months or even years with a good quality of life through the right combination of treatment and comfort care.

No matter what path you choose, the most important thing is ensuring your dog’s remaining time is full of love, comfort, and dignity.

If you’d like personalized guidance, schedule a teleconsult with one of our compassionate veterinarians. We’ll review your pet’s records, discuss your options, and help you craft a care plan that aligns with your values.

And when it does come time to say goodbye, Paws at Peace offers in-home euthanasia in all five boroughs of NYC — Manhattan, Brooklyn, Queens, the Bronx, and Staten Island — 7 days a week.