Feline squamous cell carcinoma

Among the most common malignant cancers of cats, feline squamous cell carcinoma has a wide range of survival expectations and treatments. The neoplasm tends not to produce distant metastases, but is highly invasive, and, especially in the mouth cavity, can interfere with quality of life.

Early diagnosis is key. A biopsy is likely to be needed, possibly aspirational but preferably incisional. If in the oral cavity, a high index of suspicion for infection should be kept and appropriate antibiotic therapy used aggressively.

Treatment

Detected very early, the tumor may be removable by surgery, but, in most cases, it is inoperable yet the surgery allows a definitive histopathological diagnosis.

Specific tumor reduction

Assuming the owner authorizes active treatment, the first steps are radiation or radiation coupled with chemotherapy, followed by additional cycles of chemotherapy and possibly additional radiation. One series using these methods, with bleomycin or carboplatin after fractionated electron beam radiotherapy, had survivals from 11 to over 400 days, with a median of 90. Other protocols have substantially extended life.

Some of the tumors express cyclooxygenase-2, so a selective NSAID offers both pain relief and the potential to reduce the inflammation of a tumor. Unfortunately, these agents also can cause life-threatening gastrointestinal bleeding. It is not yet standard practice to administer them with a prophylactic proton pump inhibitor or histamine H2 antagonist.

Experimental treatments

Various studies have used electric stimulation, hyperthermia and hyperbaric oxygen as a supplement to chemotherapy or radiotherapy. Photosensitization and photodynamic therapy is being explored.

Quality of life

The tumor itself may not be painful; the concern, especially in oral cancers, is that it interferes with eating or breathing.

The cat may suffer pain after manipulation of the tumor for examinations or oral medication, or perhaps by trauma (e.g., while eating). Pain management is a challenge in cats, due to their intolerance of many opioid analgesics. Gabapentin, orally or by a skin-absorptive gel, can provide baseline pain relief. Buprenorphine, orally, in the buccal cavity, or subcutaneously is useful for breakthrough pain.

Complications

Especially in the oral cavity, the owner and clinician must be alert to secondary infection.