Checkpoint inhibitors may work best “when the kidney and kidney tumor are still in place, because there are more cancer cells and molecules for the immune system to recognize and treat.”

Checkpoint-inhibitor drugs unleash immune cells that have been inactivated by cancer, allowing the body to mount a powerful defense against cancer cells. In renal cell carcinoma (RCC), “these drugs have been shown to shrink tumors, prolong survival, and occasionally offer cures for patients in whom the cancer has spread,” says Mohamad Allaf, M.D., Director of Minimally Invasive and Robotic Surgery. New studies suggest that the timing of these drugs may make an important difference – that checkpoint inhibitors may work best “when the kidney and kidney tumor are still in place, because there are more cancer cells and molecules for the immune system to recognize and treat.”

In a recent investigation, published in European Urology Oncology, Allaf and colleagues administered nivolumab (a potent checkpoint inhibitor) before surgery in 17 patients with large or locally advanced RCC. The study was designed to prove the safety of this approach, and it did; patients had very few side effects and no surgical complications were attributed to the drug. But that’s not all the study showed: “Our early laboratory analyses indicate that the drug leads to promising immune infiltration of the tumors, and oncologic analyses demonstrate very few recurrences at two years.” This work was published in European Urology Oncology.

Building on this work, a large-scale, randomized clinical trial called PROSPER has treated about 700 patients with nivolumab before and just after nephrectomy; Allaf is the principal investigator of this study, as well. “We hope the results of PROSPER, coupled with our earlier results, will dramatically change the management of patients with RCC.”