(Proton, Neutron, Or Helium Ion) Radiation Therapy The801.023 ______Coverage
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CHARGED-PARTICLE (PROTON, NEUTRON, OR HELIUM ION) RADIATION THERAPY THE801.023 _________________________________________________________________ COVERAGE: Charged-particle using radiation therapy with proton, neutron, or helium ion beams is considered medically necessary in the following: · As primary therapy for melanoma of the uveal tract (iris, choroid, or ciliary body), in patients with no evidence of metastasis or extrascleral extension, and with tumors up to 24mm in largest diameter and 14 mm in height; · As postoperative therapy (with or without conventional high-energy x-rays) in patients who have undergone biopsy or partial resections of; § a chordoma of the basisphenoid region (skull-base chordoma), § a low-grade (I or II) chondrosarcoma of the basisphenoid region (skull-base chondrosarcoma), or § cervical spine. Patients eligible for this treatment have a residual localized tumor without evidence of metastasis; · As primary therapy for early localized prostate cancer. _________________________________________________________________ DESCRIPTION: Charged particle beams consisting of 3 to 5 fixed beams of protons, neutrons, or helium ions are a type of particulate radiation therapy that contrasts with conventional electromagnetic (i.e., photon) radiation therapy. This contrast is due to the unique properties of minimal scatter as the particulate beams pass through the tissue and deposition of the ionizing energy at a precise depth (i.e., the Bragg peak). Thus, radiation exposure to surrounding normal tissues is minimized. The theoretical advantages provided by protons and other charged-particle can exploit beams for clinical gains when the following conditions apply: · Conventional treatment modalities do not provide adequate local tumor control; · The likelihood of metastasis prior to radiotherapy is small to nonexistent; · There is evidence that local tumor response depends on the dose of radiation delivered; · Delivery of an adequate radiation dose to the tumor is limited by the proximity of vital radiosensitive tissues or structures. This type of radiation therapy should not be confused with Intensity Modulated Radiation Therapy (IMRT), a rapidly evolving technique of conformal radiation planning and delivery. IMRT narrows the beam radiation using electrons rather than protons. _________________________________________________________________ RATIONALE: Charged-particle beam radiation therapy has been most extensively studied in uveal melanomas. The available evidence suggests that charged-particle beam radiation therapy is as effective as, and may be superior to alternative therapies, including conventional radiation or resection as treatment for chordomas, chondrosarcoma of the skull base, or cervical spine. In a 260 patient study with early stage prostate cancer (defined as stages T1-T2B, PSA < 15ng/mL or less, with no prior hormonal therapy or surgery), the actuarial four year freedom from biochemical relapse for all patients was 84%. When broken down by clinical stage, the chance of showing no evidence of disease was 97% for stage T1 patients, 83% for stage T2A, and 80% for stage T2B. In a second study of 319 patients with the same parameters and protocol, the overall five year clinical and biochemical disease-free survival rate was 97%. It appears that those patients treated with conformal protons have comparable survival rates to those that undergo radical prostatectomy and they also display no significant toxicity. _________________________________________________________________ DISCLAIMER: State and federal law, as well as contract language, including definitions and specific inclusions/exclusions, takes precedence over Medical Policy and must be considered first in determining coverage. The member’s contract benefits in effect on the date that services are rendered must be used. Any benefits are subject to the payment of premiums for the date on which services are rendered. Medical technology is constantly evolving, and we reserve the right to review and update Medical Policy periodically. HMO Blue Texas physicians who are contracted/affiliated with a capitated IPA/medical group must contact the IPA/medical group for information regarding HMO claims/reimbursement information and other general polices and procedures. ______________________________________________________________________ Blue Cross and Blue Shield of Texas, a Division of Health Care Service Corporation, a Mutual Legal Reserve Company* Southwest Texas HMO, Inc.* d/b/a HMO BlueÒ Texas * Independent Licensees of the Blue Cross and Blue Shield Association ______________________________________________________________________ Posted Jan. 7, 2003.