BREAKING NEWS ON THE CANCER FRONT

Particle Therapy Accelerator Penetrates Cancerous Tumors
And Blood Protein May Lead To Cancer Vaccine

Particle Therapy

     New age particle therapy to target inoperable brain and prostate can­cers are on the cutting edge of medical technology.

     Siemens Medical Solutions is installing the first Combined Particle Therapy Solution in Europe at the University Clinic at Heidelberg, Germany.

     It will use a variable energy accelerator to penetrate directly into cancerous tumor cells with­out damaging healthy tissue.

     Its creators say they expect the advanced, high technology proce­dure will establish "a new bench­mark" in the treatment of difficult to deal with tumors.

     "With this step, we have met the important technical prerequi­sites that allow us to begin treat­ing patients with tumors that up to now have been considered to be incurable," said Imtraut Gurkan, director of Administration of the University Clinic Heidelberg.

     "By using different particle therapies, a wider variety of tumor sites may be treated."

     The primary treatments will be tumors located in the brain and prostate, as well as soft tissue sar­comas.

     The system, which will be ca­pable of treating tumors with both carbon ions and protons, is ex­pected to begin treating patients in 2007.

     The treatment facility will in­clude space for three rooms that can treat patients with carbon ions and protons, as well as fa­cilities for approximately 80 support staff who will handle patient care and logistics, as well as research and develop­ment.

     The facility is expected to treat at least 1,000 patients each year, mostly on an outpatient basis.

     The use of particles like carbon ions and protons provides treatments that are highly accurate and have high biological effectiveness. The particles are accelerated to a very high speed by a variable energy accelera­tor. The particles are then de­posited directly into the tumor, where they cause irreparable damage to the tumor cells while sparing the normal surrounding tissues.

     "Siemens is pleased to have the University Clinic Heidelberg as our partner in this endeavor," stated Walter Folberth, Ph.D., senior vice president of Siemens Medical Solutions, and head of the Particle Therapy division.

     "Particle therapy treatments have shown excellent success rates, and the University Clinic has established an excellent repu­tation for particle therapy treat­ments with their existing facility in Darmstadt.

     "As the first European center to offer both proton and carbon ion treatments, we expect that a new benchmark in treatment out­comes will be established."

     Scientific, technical and clini­cal prerequisites for the Heidelberg Ion Beam Therapy Center (HIT) were a joint project of the University Clinic Heidelberg, the German Cancer Research Center (DKFZ), the Gesellschaft fur Schwerionenforschung (GSI) and the Research Center Rossendorf (FZR).

     Siemens Medical Solutions of Siemens AG with headquarters in Malvern, Pennsylvania and Erlangen, Germany, is one of the largest suppliers to the healthcare industry in the world.

     The company is known for bringing together innovative med­ical technologies, healthcare in­formation systems, management consulting, and support services, to help customers achieve tangible, sustainable, clinical and financial outcomes.

Blood Protein

     High levels of a recently identified protein in the blood may accu­rately and promptly estimate a cancer patients prognosis alter bone marrow transplantation.

     It offers hope of a future cancer vaccine.

     The protein, interleukin-12, or IL-12, may, give doctors the abil­ity to accurately assess a cancer patient's long-term prognosis a mere week after bone marrow transplantation.

     "What we found was patients with high levels of IL-12 in the blood after transplantation did quite well after transplantation in the way of less cancer relapse and improved survival after transplantation, suggesting that IL-12 is important in the fight against cancer," said Vijay Reddy, M.D., Ph.D., an assistant professor of hematology and on­cology at the University of Florida's College of Medicine who also is affiliated with the UF Shands Cancer Center.

     "The concept of a cancer vac­cine is to boost the immune sys­tem as one would for chickenpox or measles in trying to prevent those diseases," he said. "In the future, we hope to be able to challenge the immune system so it can recognize cancer before it's full-blown and be able to fight it - to be able to treat can­cer with the immune system itself."

     "What is most intriguing is that Dr. Reddy is measuring lev­els within the first week of trans­plantation and correlating these results with outcome down the road, specifically the risk of re­lapse and death." said Kenneth R. Cooke, M.D., an assistant pro­fessor of pediatrics at the University of Michigan Cancer Center.

Study Findings

     Doctors have had no reliable way of determining patients' chances of relapse or death in the long run. They estimate progno­sis by how well the bone marrow donor and recipient are matched, the kind of cancer the patient has and how well treatments prior to the transplant have controlled the disease.

     University of Florida researches identified the protein linked to remission in patients who have undergone bone mar­row transplantation for blood borne cancers such as leukemia or lymphoma.

     The protein's role in the body's hunt for insurgent cancer cells has yet to be fully defined, but study findings presented at the American Society of Hematology in San Diego showed patients with high levels soon after transplantation were twice as likely to survive as those with low levels.

     In addition, patients with high levels of IL-12 experienced no increase in adverse effects after transplantation, such as graft vs. ­host disease, in which trans­planted cells the graft don't discern between healthy tissues and cancer and attack both.

     The findings suggested the protein could someday be used to rev up the immune system to more effectively fight cancer, Reddy said. The results also built on related UF research on den­dritic cells, the captains of the immune system that normally initiate the body's response to in­fection or disease, ordering a molecular army of soldier like cells to the front lines.

     When dendritic cells are pro­duced in large enough numbers after blood stem cell transplanta­tion, they appear to launch the body's fight against the return of blood-borne cancers without at­tacking a patient's healthy tis­sues. These cells are believed to generate IL-12.

High Levels

"By looking at IL-12, we're able to identify how the immune system is functioning," said Reddy, adding that researchers eventually hope to evaluate whether the protein could some­day be used to strengthen the im­mune system's anticancer response.

     Each year, an estimated 30,000 patients undergo a bone marrow or peripheral blood stem cell transplant for a diagnosis of leukemia or another blood dis­ease. Both types of transplanta­tion aim to restore patients' blood stem cell counts after their own stem cells have been wiped out by high-dose chemotherapy or radiation therapy used to treat cancer.

     After they are infused into the bloodstream, stem cells take up residence in the bone marrow, where they give rise to the im­mune system's infection-fighting white blood cells, red blood cells or platelets.

     UF researchers studied 120 cancer patients who received a bone marrow transplant. In the first week after the procedure, 46 patients had low levels of IL-12, 49 patients had medium, levels and 25 patients had high levels.

     Those with high levels were less likely to relapse and were more likely to survive if they did than patients with lower levels. At 500 days post-transplant, 49 percent of those in the low-level group had relapsed, compared with only 23 percent in the high ­level group.

     Those with high IL-12 levels also were more likely to survive without ever relapsing at all and experienced no increase in trans­plant-related side effects. The re­search is part of an ongoing quest to identify cells that, when transplanted into a cancer pa­tient will not attack the body yet will recognize residual cancer cells and target them, a benefi­cial phenomenon known as graft ­vs. leukemia, Reddy said.