Squamous Cell Carcinoma in Rabbits

Squamous cell carcinoma, often shortened to SCC, is a malignant tumor that develops from squamous epithelial cells. These cells make up the outer layers of the skin and also line some body surfaces. In rabbits, SCC is most often discussed as a skin cancer, though squamous tumors can also affect other locations.

This cancer can start as a small crust, sore, or thickened patch that does not heal. Over time, it may become ulcerated, bleed, invade nearby tissue, and cause pain. Some lesions grow slowly at first, which can make them easy to mistake for a wound, abscess, or chronic skin irritation.

A retrospective study of pet rabbits found cutaneous SCC among the skin tumors diagnosed in domestic rabbits, supporting that this is a real, though not everyday, cancer seen in companion rabbits. Because rabbits often hide discomfort, a lesion may be more advanced than it first appears. That is why any persistent skin lesion deserves a prompt exam with your vet.

There is not one single cause of SCC in rabbits. Like many cancers, it likely develops from a mix of risk factors that damage cells over time. In veterinary medicine across species, chronic ultraviolet light exposure is a recognized contributor to cutaneous SCC, and rabbit-focused sources note that white or lightly pigmented rabbits may be more vulnerable to sun-related skin injury.

Chronic inflammation or repeated irritation may also play a role in some cases. A lesion that is repeatedly traumatized, infected, or slow to heal can create ongoing tissue damage. That does not mean every irritated area becomes cancer, but it is one reason your vet may want to sample a stubborn skin lesion rather than keep treating it as a simple wound.

Age may matter too. Many cancers are more common in middle-aged to older rabbits, although SCC is not limited to seniors. In wild rabbit species, papillomavirus-associated lesions have also been studied, but that does not mean pet rabbit skin masses should be assumed to be viral. For an individual rabbit, the practical takeaway is this: persistent skin changes need diagnosis, not guesswork.

Diagnosis starts with a hands-on exam and a careful history. Your vet will look at the lesion's size, location, depth, surface changes, and whether nearby lymph nodes feel enlarged. Photos showing how fast the lesion changed can be very helpful.

A biopsy or surgical removal with histopathology is usually needed to confirm SCC. Fine-needle aspirates sometimes help rule in or out other problems, but surface tumors can be difficult to classify accurately without tissue architecture. Histopathology tells your vet whether the mass is cancer, how aggressive it appears, and whether the sample edges are clean if the lesion was removed.

Depending on the location and how invasive the mass seems, your vet may also recommend blood work, skull or body radiographs, or advanced imaging such as CT. These tests help with anesthesia planning, surgical mapping, and checking for local invasion or spread. Rabbits with cancer often benefit from an exotics-focused veterinarian or referral center because anesthesia, pain control, and recovery planning are different in rabbits than in dogs and cats.

Not every case of SCC can be prevented, but you can lower risk by reducing avoidable skin damage and catching changes early. For rabbits with white fur, pink skin, thin fur coverage, or outdoor time, limit intense direct sun exposure, especially during peak midday hours. Provide reliable shade and avoid long periods in sunny enclosures.

Check your rabbit's skin regularly during grooming and handling. Look for crusts, sores, scabs, thickened patches, or bumps that do not resolve. Early lesions can be subtle. A small abnormal area is much easier for your vet to evaluate and treat than a large ulcerated mass.

Prompt care matters. If a wound keeps reopening, a scab returns in the same spot, or a skin lesion does not heal as expected, schedule an exam rather than continuing home treatment indefinitely. Prevention is partly about sun safety, but it is also about not ignoring persistent skin changes.