His pioneering research established interleukin-2 (IL-2) as the first U.S. Food and Drug Administration–approved cancer immunotherapy in 1992.
To recognize his trailblazing work and other achievements, the American Association for Cancer Research (AACR) will award Dr. Rosenberg with the 2024 AACR Award for Lifetime Achievement in Cancer Research at its annual meeting in April.
Dr. Steven A. Rosenberg
Dr. Rosenberg, a senior investigator for the Center for Cancer Research at the National Cancer Institute (NCI), and chief of the NCI Surgery Branch, shared the history behind his novel research and the patient stories that inspired his discoveries, during an interview.
Tell us a little about yourself and where you grew up.
Dr. Rosenberg: I grew up in the Bronx. My parents both immigrated to the United States from Poland as teenagers.
As a young boy, did you always want to become a doctor?
Dr. Rosenberg: I think some defining moments on why I decided to go into medicine occurred when I was 6 or 7 years old. The second world war was over, and many of the horrors of the Holocaust became apparent to me. I was brought up as an Orthodox Jew. My parents were quite religious, and I remember postcards coming in one after another about relatives that had died in the death camps. That had a profound influence on me.
How did that experience impact your aspirations?
Dr. Rosenberg: It was an example to me of how evil certain people and groups can be toward one another. I decided at that point, that I wanted to do something good for people, and medicine seemed the most likely way to do that. But also, I was developing a broad scientific interest. I ended up at the Bronx High School of Science and knew that I not only wanted to practice the medicine of today, but I wanted to play a role in helping develop the medicine.
What led to your interest in cancer treatment?
Dr. Rosenberg: Well, as a medical student and resident, it became clear that the field of cancer needed major improvement. We had three major ways to treat cancer: surgery, radiation therapy, and chemotherapy. That could cure about half of the people [who] had cancer. But despite the best application of those three specialties, there were over 600,000 deaths from cancer each year in the United States alone. It was clear to me that new approaches were needed, and I became very interested in taking advantage of the body’s immune system as a source of information to try to make progress.
Were there patients who inspired your research?
Dr. Rosenberg: There were two patients that I saw early in my career that impressed me a great deal. One was a patient that I saw when working in the emergency ward as a resident. A patient came in with right upper quadrant pain that looked like a gallbladder attack. That’s what it was. But when I went through his chart, I saw that he had been at that hospital 12 years earlier with a metastatic gastric cancer. The surgeons had operated. They saw tumor had spread to the liver and could not be removed. They closed the belly, not expecting him to survive. Yet he kept showing up for follow-up visits.
Here he was 12 years later. When I helped operate to take out his gallbladder, there was no evidence of any cancer. The cancer had disappeared in the absence of any external treatment. One of the rarest events in medicine, the spontaneous regression of a cancer. Somehow his body had learned how to destroy the tumor.
Was the second patient’s case as impressive?
Dr. Rosenberg: This patient had received a kidney transplant from a gentleman who died in an auto accident. [The donor’s] kidney contained a cancer deposit, a kidney cancer, unbeknownst to the transplant surgeons. [When the kidney was transplanted], the recipient developed widespread metastatic kidney cancer.
[The recipient] was on immunosuppressive drugs, and so the drugs had to be stopped. [When the immunosuppressive drugs were stopped], the patient’s body rejected the kidney and his cancer disappeared.
That showed me that, in fact, if you could stimulate a strong enough immune reaction, in this case, an [allogeneic] reaction, against foreign tissues from a different individual, that you could make large vascularized, invasive cancers disappear based on immune reactivities. Those were clues that led me toward studying the immune system’s impact on cancer.
From there, how did your work evolve?
Dr. Rosenberg: As chief of the surgery branch at NIH, I began doing research. It was very difficult to manipulate immune cells in the laboratory. They wouldn’t stay alive. But I tried to study immune reactions in patients with cancer to see if there was such a thing as an immune reaction against the cancer. There was no such thing known at the time. There were no cancer antigens and no known immune reactions against the disease in the human.
Around this time, investigators were publishing studies about interleukin-2 (IL-2), or white blood cells known as leukocytes. How did interleukin-2 further your research?
Dr. Rosenberg: The advent of interleukin-2 enabled scientists to grow lymphocytes outside the body. [This] enabled us to grow t-lymphocytes, which are some of the major warriors of the immune system against foreign tissue. After [studying] 66 patients in which we studied interleukin-2 and cells that would develop from it, we finally saw a disappearance of melanoma in a patient that received interleukin-2. And we went on to treat hundreds of patients with that hormone, interleukin-2. In fact, interleukin-2 became the first immunotherapy ever approved by the Food and Drug Administration for the treatment of cancer in humans.