When Greylock arrived for his appointment, his owner and I spent some time chatting on the porch. The handsome grey middle-aged cat had originally been a stray. “He was almost feral but crying for food at my doorstep and then refusing to leave the property for a few weeks,” she told me. She described his behavior back then — slinking about and hissing whenever he saw her. In fact, he seemed so vicious at first she was afraid he might have rabies and kept her other cats safely away from him. But over time he had become tamer. She named him Greylock.
Two years ago when I first met him, Greylock had a condition in both eyes called feline eosinophilic keratitis (FEK). No one knows exactly what causes FEK, though it is sometimes related to chronic feline herpesvirus-1 infection. Greylock had classic lesions — raised pinkish-white plaques on his corneas that were painful and occluding his vision. He was lucky he did not have any other issues that may come with FEK, such as corneal ulcers. Diagnosis is usually made based on physical exam and history, though corneal biopsy or scraping can be done to confirm. In Greylock’s case I simply prescribed the standard treatment for cases without corneal ulceration — topical ophthalmic ointment containing corticosteroids. “This should help,” I said, “but there are other medications we can try if it doesn’t.” Lesions often resolve completely with treatment, although it can sometimes take weeks to months, and recurrence rates are very high. “This condition is treatable,” I added, “but not really curable.”
Greylock’s next problem was his foot. One toe was massively swollen and oozing fluid from the pad. If this had been a brand new lesion, I might have thought it was an infected bite wound or the result of some other injury, but this swelling had been going on for a while. Although trauma and infection were still on my differential diagnosis list, so were other possibilities. Pododermatitis, eosinophilic granuloma complex, cancer.
Plasma cell pododermatitis is another quirky cat disease, also called “pillow foot” because of the way the affected foot pads puff up like big squishy down pillows. An immune-mediated inflammatory condition of unknown cause sometimes linked to feline immunodeficiency virus (FIV), pododermatitis may affect one or more paws, and the swollen pads may ulcerate and develop secondary bacterial infections. Eosinophilic granuloma complex is another odd disease with a fancy name whose etiology is also not really well understood. It usually causes lesions on the lips, chin, thighs, or belly, but can occasionally affect the foot pads. Could Greylock’s foot and eyes be connected? I wondered.
Treatment for pododermatitis may include oral doxycycline, used primarily for its immune-modulating effects as much as for its antibiotic properties, and/or high doses of prednisolone. Since pododermatitis, eosinophilic granuloma complex, and feline eosinophilic keratitis all often respond to systemic prednisolone or other corticosteroids, we tried various forms of cortisone, sometimes paired with antibiotics. I’ve also seen cats with these diseases improve when switched to a hypoallergenic diet, but that is hard to do with an outdoor, semi-feral cat, especially in a multiple cat household. Over the next year our various treatments met with varying degrees of success but eventually we decided to amputate the affected toe and biopsy the lesion.
Last summer, when we removed his toe and submitted it for biopsy, Greylock was officially diagnosed with histiocytic sarcoma — a form of malignant cancer fairly common in dogs but rare in cats. Histiocytic sarcoma can present as a single localized tumor, multiple tumors at different sites, or cancer disseminated throughout the body. It primarily affects middle-aged to older cats. Symptoms depend on the location and extent of the cancer. In Greylock’s case, we hoped the toe amputation would cure him. Post-operatively, we discussed consulting with an oncologist about radiation or chemotherapy but, all things considered, this seemed more than Greylock would tolerate. For a while we were optimistic but five months later, the tumor reappeared on the same foot. His owner struggled with what to do. Greylock was in pain again. The choices seemed to be amputation or euthanasia. Could he adjust at this late stage of life to getting around with three feet? After much deliberation, his owner decided to give him a chance and opted for amputating the lower leg. Greylock recovered and adapted well.
Again, we were hopeful. Then last month a pea-sized lesion appeared on Greylock’s lower lip. Another histiocytic sarcoma? Something else? “What would you do if it was your cat?” his owner asked. Many veterinarians hate that question. Me, I don’t mind at all . . . but I do know that what I would do is not necessarily what you would do. Much depends on how risk averse you are. It’s like investing in the stock market, or betting on a poker hand. How much are you willing to risk? Do potential benefits outweigh potential harm? The prognosis for histiocytic sarcoma in cats is poor, with survival times often measured in days or months, not years. Greylock was already beating the odds. “If we want to do surgery, we should do it now, while the lesion is small,” I replied. “I would probably go for it, but remember there are no guarantees.”
“Why did you name him Greylock?” I asked later that day when she came to pick him up after surgery. She told me about Mount Greylock in the Berkshires. How he somehow had reminded her of the mountain. There was a word she felt explained the feeling behind his name. He was, she said, indomitable. “Eyes clouded over or half blind, tumors on his foot . . . but surviving nevertheless. Feisty in his self-defense and determined to thrive. I couldn’t resist taking him in and giving him a soft bed and warm home in his later years.” Whatever the biopsy results are this time round, however many weeks or months or years he may have left, the indomitable Greylock will spend them in a soft bed and a warm home. Purr.