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Everyone with an interest in medicine and healthcare keeps a watchful eye for "the next big thing." Patients, clinicians, researchers, drug companies, investors, journalists -- we all want to be ready for the next "breakthrough." OncoBlog is a blog by the 番茄社区 Medical Today staff for readers with an interest in oncology. This post comes from Charles Bankhead.

As most of my colleagues in medical reporting will agree, the term "breakthrough" gets tossed around far too often and far too casually. In most cases, breakthroughs get all the credit when the underlying technology made it all possible. Case in point: monoclonal antibodies. Consider all of the major therapies that have names ending in "-mab." They're all monoclonal antibodies.

Concepts and contributions dating back to the early 20th century culminated in the development of the first human monoclonal antibodies in the mid-to-late 1980s. The ability to produce identical clones from a single unique parent cell became integral to laboratory research and clinical medicine.

Perhaps no field of medicine has gotten more mileage from the term breakthrough (legitimately or otherwise) than oncology. The historical fear and loathing that surround cancer have made it ripe for new (and sometimes false) hope spawned by the designation of a clinical or scientific development as a breakthrough.

In reality, breakthroughs in medicine occur infrequently. At the risk of incurring the ire of people who think their favorite breakthrough has been snubbed, I'll mention a few developments that come to mind as breakthroughs: tamoxifen, first for treatment and then prevention of breast cancer; trastuzumab (Herceptin), which has helped extend the life of untold numbers of women with an aggressive form of breast cancer; imatinib (Gleevec), which many credit with revolutionizing (another overused term) the treatment of chronic myelogenous leukemia.

Today, improved cancer survival tends to occur incrementally. A few months here, a few months there, and before you know it, you've added several years to a person's life. In some cases, patients are cured, when years ago their diagnosis would have been terminal.

That brings me to the subject of this essay: The next big thing in cancer. In the interest of mollifying critics, I probably should say "one of the next big things," but I won't.

At the recent American Society of Hematology meeting, the majority of a press conference was devoted to advances in therapeutic use of chimeric antigen receptors, or CARs. In 番茄社区's preview story before the meeting, ASH president Janis Abkowitz, MD, said meeting organizers would have included an entire session on CARs, had they known that the subject would be such a hot topic by the end of 2013. Instead, meeting planners added a special session to review some of the notable research.

In essence, CAR technology offers a means to ignite a supercharged immunologic attack against cancer cells. Simply put, CARs are bioengineered receptors with tumor antigen-specific activity. When introduced into T-cells (and other immunologic cells), CARs lead to rapid generation of tumor-targeted T cells that speed past many of the obstacles to conventional immunization. For example, studies conducted thus far have demonstrated penetration of the blood-brain barrier, a limitation of many therapies for cancers that metastasize to the brain. Researchers believe the technology can be adapted to multiple types of hematologic malignancies and at least some solid tumors.

For those of you with a thirst for knowledge about these sorts of things, check out this article published earlier this year in .

Back to the press conference at the ASH meeting. Speakers who have been helping to lead the way in CAR research shared some of their results:

• Michael Kalos, PhD, of the University of Pennsylvania in Philadelphia, reported that six of six patients with chronic lymphocytic leukemia (CLL), three of four children with acute lymphoblastic leukemia (ALL), and two of two adults with ALL had total absence of B-cells in their blood, marrow, or both after treatment with CAR-redirected T-cells targeting CD19.
• Stephan Grupp, MD, PhD, also of the University of Pennsylvania, reported remission rates of about 90% in more than 60 patients with relapsed ALL (children and adults) and with CLL after induction therapy with CAR-induced T-cell targeting of CD19.
• , of the National Cancer Institute, said 12 of 13 evaluable patients with refractory B-cell lymphoma had complete or partial remissions after treatment with engineered autologous T-cells expressing an anti-CD19 CAR.

Small sample size aside, results have been at least encouraging, if not yet worthy of the term breakthrough. Many of these patients had run out of options.

Only time will tell whether CAR-directed T-cells represent a breakthrough in cancer treatment. In a recent article by , , and David P. Steensma, MD, both of Harvard, concluded that "use of CAR T-cells is likely to be practice changing, not only in the realm of lymphoid malignancies, but also for other neoplasms."

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