As a young student first pursuing medicine, Mark Kirschbaum, M.D., began working with health professionals who gave chemotherapy to patients in an inner-city cancer ward — and cancer’s toll on patients shocked him.

“How do you get used to seeing people dying all the time?” Kirschbaum asked the physician in charge of the department.

“Don’t ever get used to it,” the doctor warned. “You’re not here to get used to it; you’re here to fight it.”

Since becoming a hematologic oncologist in the early ‘90s, Kirschbaum, the Tim Nesvig Lymphoma Fellow at City of Hope, has been fighting not only cancer but also the notion of “standard therapy.” As he treated patients with blood cancers, he grew frustrated that standard therapies not only were painful, hard to tolerate and sometimes disfiguring, but also were not effective enough.

He began searching for therapies that offered patients better odds.

Before joining City of Hope, he helped develop protocols for potential new therapies against a variety of cancers and was part of a team that first developed a less intense stem cell transplant regimen, now widely used.

Kirschbaum joined City of Hope in 2003 and directs new drug development for the Division of Hematology & Hematopoietic Cell Transplantation. He also coordinates clinical trials for patients with hematologic malignancies within the California Cancer Consortium — a major part of City of Hope’s assessment of potential new treatments through the National Institutes of Health (NIH) Cancer Therapy Evaluation Program.

Today, he pursues potential new targeted and epigenetics-based drugs for hematologic cancers, testing them in the lab and then taking them to patients. Often, he is among the first to offer certain drugs to patients through clinical trials.

Among his targets are lymphomas, cancers that arise in the lymph nodes, glands that filter the blood and rid the body of bacteria and viruses.

Kirschbaum likens lymphatic cells to firefighters on standby. “When an emergency arises, such as a bacterial infection, the cells begin reproducing,” he said. “Their job is to take out the bacteria, then turn off and stop growing and killing. But sometimes something goes wrong. Somehow, in the millions of cells that do that, one has figured out how to not turn off afterward.” A tumor is born.

Kirschbaum and colleagues are investigating molecular therapies to reprogram these cancer cells and repair this broken “off” switch. He is enthusiastic about the collaboration with colleagues that pushes the research forward, including a dedicated group of physicians, data managers and nurses — especially nurse coordinator Bernadette Pulone, R.N. — who carefully monitor patients on clinical trials.

“We’re going to unravel a set of diseases that really has a much broader impact than merely lymphoma,” he said. “What we saw in the effect in lymphocytes made us understand some of the processes in immune response — both normal and abnormal.”

His white board is nearly filled with names of 22 clinical trials in which he has participated or begun. Kirschbaum and his colleagues now are designing new NIH clinical trials to test agents alone and in unusual combinations, and they are receiving increasing requests from companies wanting to test new drugs. “Sometimes we bounce people from one drug to another until they get some response to it — until we find the one that will really cure them,” he said.

They aim to buy quality time for patients. He has seen patients told they had three weeks to live suddenly rebound through new therapies.

“There are days,” Kirschbaum said, “when it’s so exhilarating to be alive.”

At age 28, City of Hope patient Tim Nesvig was diagnosed with non-Hodgkins lymphoma. After an 18-month struggle, including an autologous bone marrow transplant at City of Hope, he died on Feb. 8, 2005. The disease overcame him, said his family, but it never defeated him. To honor his memory and try to spare other families a similar loss, the Nesvig family established the Tim Nesvig Fellowship for Lymphoma Research, now supported by hundreds of donors, to help fund the work of innovative specialists such as Mark Kirschbaum, M.D., the 2007-08 recipient.