Clinical signs of cancer in horses can be vague, nonspecific (such as weight loss, failure to gain weight, or fever), and unapparent until the disease is in an advanced state, making it challenging to diagnose. | Photo: iStock

Cancer might be rare in horses compared to humans and small animals, but it occurs and requires treatment nonetheless, often with chemotherapy. It hasn’t always been clear, however, just how effective chemotherapy is at fighting equine cancer. But recent research suggests that, for equine lymphoma at least, chemotherapy can help horses achieve remission and extend their lifespans for several months or years.

At the 2018 American College of Veterinary Internal Medicine Forum, held June 14-16 in Seattle, Washington, Daniela Luethy, DVM, Dipl. ACVIM, a large animal internal medicine lecturer at the University of Pennsylvania School of Veterinary Medicine, in Kennett Square, shared the results of a study she and colleagues conducted to evaluate the long-term outcomes of treated equine lymphoma cases.

Clinical signs of cancer in horses can be vague, nonspecific (such as weight loss, failure to gain weight, or fever), and unapparent until the disease is in an advanced state, making it challenging to diagnose. Lymphoma is a type of hematologic (blood) cancer in which the tumor cells arise from lymphocytes, a type of white blood cell. Multicentric lymphoma can, essentially, affect the entire body, whereas cutaneous lymphoma affects the skin