Dog Toe Cancer: What to Know

Toe cancer in dogs is uncommon (Marconato et al., 2021), but when a toe is removed because of a mass or a persistent problem, the cause is often a tumor. In a study of 404 amputated dog toes sent to diagnostic laboratories, 73% had a tumor, and 77.7% of those tumors were malignant. The most common were squamous cell carcinoma (36.3%), melanoma (17.3%), soft tissue sarcoma (9.7%), and mast cell tumor (6.7%) (Wobeser et al., 2007).

Toe cancer is easy to miss because it looks like other toe problems: a swollen toe, a nail that's loose or falls out, a sore that won't heal, or limping. In a study of 79 dogs with toe squamous cell carcinoma, signs had been present for a median of 90 days before referral, and longer delays were linked to the cancer progressing (Marconato et al., 2021).

Removing the affected toe usually controls the cancer locally and also provides the tissue needed for a diagnosis (Marconato et al., 2021; Mouser, 2026). For toe squamous cell carcinoma, 81% of dogs were alive at one year and 60% at two years after treatment (Marconato et al., 2021). Toe melanoma has a more guarded outlook, with a median survival of 365 days in one study (Wobeser et al., 2007).

Key points

• Most tumors found in amputated dog toes are malignant, most often squamous cell carcinoma or melanoma (Wobeser et al., 2007).
• Toe squamous cell carcinoma mostly affects large, dark-coated dogs. Breeds named include Giant Schnauzers, Standard Poodles, black Labrador Retrievers, Gordon Setters, Rottweilers, Beaucerons, and Briards (Belluco et al., 2013; Marconato et al., 2021).
• Signs often look like an infection or nail injury, which delays diagnosis (Marconato et al., 2021).
• Bone destruction on X-rays is very common with toe squamous cell carcinoma, seen in 92.4% of dogs in one study (Marconato et al., 2021), but it also happens with infections and doesn't predict how serious a lesion is (Mouser, 2026).
• About 1 in 5 dogs with toe squamous cell carcinoma later develop a new tumor on another toe (Belluco et al., 2013; Marconato et al., 2021).
• Toe melanoma has a median survival of about one year (Wobeser et al., 2007).

Detailed explanation

What dog toe cancer looks like

Owners usually notice one of these:

• A swollen, red, or enlarged toe
• A nail that's cracked, loose, deformed, or missing
• A sore or "infection" around the nail bed that keeps coming back
• Limping or licking at one foot

Lameness was the most common reason for referral (58.2%) among dogs with toe squamous cell carcinoma, and the front feet were affected in 61% (Marconato et al., 2021). Toe lesions are often painful, especially when the bone is involved (Mouser, 2026).

The problem is that these signs mimic common, non-cancer problems such as nail bed infections and injuries. Researchers note that signs are frequently underestimated, which delays diagnosis (Marconato et al., 2021). A toe that hasn't healed after a standard course of treatment for infection deserves X-rays and a tissue sample.

The main types of toe cancer

Squamous cell carcinoma. This is the most common toe cancer in dogs. It usually starts in the nail bed (subungual squamous cell carcinoma) (Mouser, 2026; Wobeser et al., 2007). It strongly favors large, dark-coated dogs. In a study of 105 dogs, 92% were dark-haired, and 75.2% were large or giant breeds (Belluco et al., 2013). In the 79-dog study, Schnauzers made up about a third of cases, median age was 10 years, and median weight was 33 kg (Marconato et al., 2021). Our page on squamous cell carcinoma in dogs covers this cancer elsewhere on the body.

Melanoma. Melanoma of the toe accounted for 17.3% of toe tumors in the multi-laboratory study and was associated with a poor prognosis, with a median survival of 365 days (Wobeser et al., 2007). See our melanoma in dogs hub.

Other tumors. Soft tissue sarcomas, mast cell tumors, plasma cell tumors, and benign growths such as keratoacanthomas can also affect the toes (Mouser, 2026; Wobeser et al., 2007). Our pages on mast cell tumors and soft tissue sarcoma explain those.

Not every swollen toe is cancer. In the multi-laboratory study, 27% of amputated toes had inflammation alone, with no tumor (Wobeser et al., 2007).

Why toe amputation is so often recommended

X-rays of an affected toe often show bone destruction. With toe squamous cell carcinoma, it was present in 92.4% of dogs (Marconato et al., 2021). But bone destruction also occurs with infections and other non-cancer problems, so X-rays alone can't tell you what's going on or how serious it is (Mouser, 2026).

That's why toe amputation is often both the test and the treatment. Removing the toe relieves pain and provides tissue for a definitive diagnosis, and that diagnosis is what determines the prognosis (Mouser, 2026). For toe squamous cell carcinoma, amputation achieved good local control in most dogs, with local recurrence in only 3.8% (Marconato et al., 2021).

Your veterinarian will discuss which toe is involved and what recovery looks like. Our article on recovery after cancer surgery covers general aftercare.

Staging and spread

Before or after surgery, your veterinarian may check the nearby lymph nodes and take chest X-rays to look for spread. In the 79-dog study, 15.2% had spread to regional lymph nodes at diagnosis, none had distant spread at that point, and 17.7% developed spread later, mostly to the lungs (Marconato et al., 2021). In the multi-laboratory study, 11 of 42 dogs with follow-up developed metastatic disease, and the authors noted that toe squamous cell carcinoma appears to spread more readily than squamous cell carcinoma elsewhere on the body (Wobeser et al., 2007). Our article on why dogs need X-rays for cancer explains chest imaging.

Outlook for toe squamous cell carcinoma

The outlook after amputation is often good. In the 79-dog study, 81% of dogs were alive at one year and 60% at two years, and median survival wasn't reached during the study (Marconato et al., 2021). Earlier reports put one-year survival at 50% to 83% and two-year survival at 18% to 62% (Marconato et al., 2021).

Several factors were linked to worse outcomes (Marconato et al., 2021):

• Signs lasting more than 90 days before treatment
• More than one toe affected
• Spread at the time of diagnosis
• Schnauzer breed

The authors recommended reserving chemotherapy for dogs whose cancer has spread (Marconato et al., 2021).

New tumors on other toes

Dogs who have had toe squamous cell carcinoma can develop it again on a different toe. A new toe tumor developed in 22.4% of dogs in one study (Belluco et al., 2013) and in 22.8% in another (Marconato et al., 2021). After treatment, check all of your dog's toes and nails regularly, and have any new swelling or nail change examined quickly.

When to contact a veterinarian

Book an appointment soon if your dog has:

• A swollen toe or a nail bed sore that hasn't healed in about two weeks
• A nail that's loose, cracked, deformed, or fell out without an obvious injury
• Limping or licking at one foot that keeps coming back
• A new toe problem after a previous toe tumor

Call the same day if a toe is bleeding heavily, your dog won't bear weight on the foot, or the swelling is spreading up the leg.

Questions to ask your veterinarian

• Could this toe problem be a tumor rather than an infection?
• Should we take X-rays of the toe and chest?
• Would toe amputation give us a diagnosis and treat the problem at the same time?
• Should the nearby lymph nodes be checked?
• If it's squamous cell carcinoma or melanoma, what's the plan after surgery?
• How often should we recheck the other toes?

Sources

Belluco, S., Brisebard, E., Watrelot, D., Pillet, E., Marchal, T., & Ponce, F. (2013). Digital squamous cell carcinoma in dogs: Epidemiological, histological, and immunohistochemical study. Veterinary Pathology, 50(6), 1078-1082. 

Marconato, L., Murgia, D., Finotello, R., Meier, V., Morello, E. M., Pisoni, L., Foglia, A., Guerra, D., Chalfon, C., Aralla, M., Mesto, P., Annoni, M., Albanese, F., Bettini, G., & Sabattini, S. (2021). Clinical features and outcome of 79 dogs with digital squamous cell carcinoma undergoing treatment: A SIONCOV observational study. Frontiers in Veterinary Science, 8, Article 645982. 

Mouser, P. (2026, March 6). Amputate that digit! MSPCA-Angell. https://www.mspca.org/clinical/amputate-that-digit/

Wobeser, B. K., Kidney, B. A., Powers, B. E., Withrow, S. J., Mayer, M. N., Spinato, M. T., & Allen, A. L. (2007). Diagnoses and clinical outcomes associated with surgically amputated canine digits submitted to multiple veterinary diagnostic laboratories. Veterinary Pathology, 44(3), 355-361.