Potential New Treatment For Melanomas

Electrochemotherapy offers promise

Luckily, melanomas (cancers originating from pigmented cells) are rare in cats. They most commonly occur in the iris (colored part that surrounds the pupil) and limbus (border between the transparent cornea and the whitish sclera) of the eye. Iris melanomas may be malignant, while limbal melanomas are most commonly benign.

Unfortunately, melanomas around the mouth and nose of cats tend to be aggressive and fast growing. While surgery is currently considered the best option for treating these aggressive cancers, fully removing oral and nasal melanomas in cats is challenging, and prognosis after surgical excision is poor.

A recent report from North Downs Specialist Referrals in London describes a case in which electrochemical therapy (ECT),  a potential new treatment option that has been used to treat human melanomas, was used in a four year old cat with nasal melanoma. After an intravenous injection of bleomycin (a chemotherapeutic medication), electrical pulses, which make a tumor more permeable and susceptible to chemotherapy, were applied to the cat’s tumor. The treatment was repeated two weeks later.

The cat did not experience any significant negative effects of this therapy and is currently in remission after 292 days. Given the fact that the current median survival time for cats with melanomas of the mouth and nose is approximately 83 days, this case report suggests that further investigation of ECT as an option to treat cats with oral and nasal melanomas is warranted.