Lucky patient "number four", who took part in an experimental melanoma treatment program at the Fred Hutchinson Cancer Research Center in Seattle, has experienced an amazing outcome: complete remission of a malignant melanoma that had already spread to his internal organs. The New England Journal of Medicine published the report June 19.

This 52-year-old man received an infusion of his own CD4+ T cells, a specific component of the immune system. The cells were isolated from his blood and cloned, with 3.3 billion of these cells infused back into the patient. Two months later, the melanoma disappeared.

"This is further proof of something we've known all along," said Dr. Eddy Hsueh, a cancer researcher and associate professor of surgery at St. Louis University School of Medicine. "Immunotherapy can work for melanoma."

In fact, this is an expansion of a discovery that took place nearly a century ago, Hsueh said. "There have been reports of patients with metastatic cancer and, after a case of a bad pneumonia, the cancer is gone," he said. "Even spontaneous regressions of melanoma have been seen. This is what makes us believe in immunotherapy for cancer."

The science of immunotherapy

Immunotherapy is a technique that engages a patient's own immune system to fight disease . Some of these new-fangled weapons in the anti-cancer arsenal include interferons and other immune proteins known as cytokines, monoclonal antibodies and cancer vaccines.

Hsueh is investigating melanoma cancer vaccines. One clinical trial has been closed as the process was taking too long to be of benefit to the patients. Hsueh is now working in a new direction focusing on the production of a vaccine that can be more of an "off the shelf" variety, ready in as little as 1 to 2 weeks. "We have been searching for a vaccine for melanoma for many years," Hsueh said. "We did not know how complicated the immune system is."

The process of the vaccine development is quite similar to that described in the NEJM article, according to Hsueh. A patient's own immune cells, along with tumor cells, are collected, fused and expanded to then be infused back into the patient. The theory is that this form of vaccine could be used to treat an existing cancer, rather than preventing the disease which is how most vaccines work.

Renegade success

The melanoma treatment program at the Hutchinson Center "is a good example of outstanding 'investigator-initiated' research, when a scientist in a lab comes up with an idea and, without [pharmaceutical] industry support, develops and administers a new treatment on their own," said Dr. Gerald Linette, a specialist in hematology/oncology and professor of medicine at Washington University School of Medicine

The implications could be profound, as most pharmaceutical companies are not focused on these types of cellular therapies, Linette said. "These types of therapies are very involved, very labor -- and time-intensive," he said. "It is a customized type of medicine, specific to each patient and individualized."

Current techniques used in immunotherapy, such as the above mentioned monoclonal antibodies, are usually generated as a single product to be given to all patients. This new research took a different approach in a much more individualized direction.

Yet questions remain

"This is still in the research phase. It is exciting yet preliminary data and it will take more studies and more time," said Linette. "They had one good response. How can they take this and expand it to others?"

And the study was small, with only 9 participants involved and "patient four" receiving a higher dose of these cells than the first three patients but the same or lower dose than the remaining five. The first three patients had zero response and the later patients had a small response, although none with as dramatic an outcome as patient four.

So why only that one patient? Were other treatments involved that may have been key to success? Was it a "super-response" specific to him alone?

It is clear that more research is needed.

"We need more research and we need to get it funded," Linette said. "We need to be able to streamline the manufacturing process and get this out to others in other centers."

Bottom line?

"It can be done and we need to do more of it," Linette concludes.