Blood test in dogs may predict lymphoma response ^{CEFR B2}

Diffuse large B-cell lymphoma is an aggressive blood cancer for which the current standard treatment combines an antibody that targets B cells with four chemotherapy drugs. The approach cures many patients but fails in about three in ten, and the chemotherapy can cause heart damage, a serious risk particularly for older people. Because clinicians cannot reliably predict who will respond, they are often reluctant to try newer, potentially less toxic regimens.

A new study in pet dogs suggests a way to predict response at an early stage. Researchers from the Cummings School of Veterinary Medicine at Tufts University and UMass Chan Medical School re‑analysed blood samples from a previous randomized trial. In that trial, dogs received a canine antibody equivalent to the human drug plus a low dose of doxorubicin, then one of three experimental immune‑boosting therapies; two of those immunotherapies are also under human study.

Instead of sampling tumour tissue, the team measured gene activity in circulating immune cells. Samples were taken before treatment, seven days into treatment (just before the novel immunotherapy), at the end of the chemo‑immunotherapy cycle, and either when cancer returned or at 400 days if the dog remained cancer‑free. Researchers compared gene activity patterns between dogs that relapsed quickly and those that survived much longer.

The study, published in Scientific Reports, identified two genes, CD1E and CCL14, whose higher activity was linked to long‑term survival; CD1E helps T cells recognise cancer and CCL14 helps recruit other immune cells. By contrast, interferon‑stimulated genes were consistently associated with poorer outcomes, including shorter survival and early relapse, and the team suggests some interferon‑related signals may help cancerous blood cells survive in this setting. The authors also noted three early‑warning genes (TBHD, NPNT, ISG20) that were detectable one week into treatment.

Co‑senior author Heather Gardner developed a simple laboratory test to detect elevated activity of the early‑warning genes. Cheryl London plans to test whether using such a blood test to guide treatment can improve survival in dogs. The researchers say these findings point toward blood tests that could help guide more personalised treatment decisions in both veterinary and human lymphoma care.