Although immunotherapy has increased in use and popularity as a form of cancer treatment, immunotherapy isn’t effective in treating all cancers or all people who have cancer.

The efficacy of immunotherapy is partly determined by a person’s own proteins. One of the problems faced by oncologists, though, is not only that all people have different sets of proteins, but also that each person’s proteins are often in flux.

Vamsidhar Velcheti, MD, the director of thoracic oncology at NYU Langone’s Perlmutter Cancer Center, spoke with SurvivorNet about why this is the case. “Oncologists still don’t have great tools to identify patients that will have long-term responses,” says Dr. Velcheti. Even though the search for answers continues, Dr. Velcheti is hopeful. “We’re constantly learning more about the biology of cancer, and we’re able to incorporate those biomarkers into practice.”

Watch more on SurvivorNet.