Chemotherapy patients still have functional immune response

Patients treated with sunitinib and sorafenib responded to the flu vaccine, which suggests the agents do not damage the immune system as much as previously feared, according to a study in Clinical Cancer Research, a journal of the American Association for Cancer Research.

Keith Flaherty, M.D., director of developmental therapeutics at the Massachusetts General Hospital and a senior editor of Clinical Cancer Research, said the findings have broad implications beyond questions of patient management.

"The damage that chemotherapy does to normal, healthy cells as it treats cancer has been well documented, but the precise effect that the new class of targeted agents has on the immune system is less well known," he said. "This study helps us answer that question."

Flaherty said the indication that the flu vaccine is safe and effective in cancer patients treated with sunitinib and sorafenib, tyrosine kinase inhibitors that have been shown to have an effect on several types of cancer, suggests that clinicians can be less concerned about other targeted therapies.

"At the very least, it allows us to have a method of testing the capacity of the immune system when we use these agents, similar to how a stress test would test heart function," said Flaherty.

Flaherty cautioned, however, that the findings would have to be confirmed both with other tyrosine kinase inhibitors and with other classes of drugs. As a question of patient management, the effect is more conclusive, according to Flaherty.

The study, led by Carla van Herpen, M.D., Ph.D., a medical oncologist at Radboud University Nijmegen Medical Centre in The Netherlands, included 40 patients: 16 were treated with sunitinib, six were treated with sorafenib, seven patients with metastatic renal cell cancer were treated with neither drug and 11 were healthy.

The researchers observed an antibody response in all patients comparable with healthy participants.

"The exact incidence of influenza in patients with cancer is not known, however, it is definitely higher than in the general population," said van Herpen. "Managing these patients with the flu vaccine would improve their quality of life."

(Source: American Association for Cancer Research (AACR): Clinical Cancer Research)