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Abstract A 46 year old male patient with metastatic prostate cancer developed Stevens-Johnson syndrome (SJS), initially in three well-demarcated areas on his scalp, chest and back, corresponding to ports of radiation therapy while on phenytoin. The rash spread from these locations and became more generalized and associated with pain and sloughing in the mucous lining of the mouth. There is a documented association between phenytoin administration with concurrent cranial radiation therapy and development of SJS. Erythema multiforme (EM) associated with phenytoin and cranial radiation therapy (EMPACT) is the term that describes this reaction. However, this term may not cover the full spectrum of the disease since it describes EM associated with phenytoin and only cranial radiation therapy. This case report presents evidence that SJS may be induced by radiation to other parts of the body in addition to the cranium while phenytoin is administered concomitantly. With increasing evidence that phenytoin and levetiracetam are equally efficacious for seizure treatment and prophylaxis, and since there is no link identified so far of an association between levetiracetam and SJS, we believe that levetiracetam is a better option for patients who need anticonvulsant medication(s) while undergoing radiation therapy, especially cranial irradiation.

One of the fundamental attributes of proton therapy and carbon ion therapy is the ability of these charged particles to spare tissue distal to the targeted tumor. This significantly reduces normal tissue toxicity and has the potential to translate to a wider therapeutic index. Although, in general, particle therapy also reduces dose to the proximal tissues, particularly in the vicinity of the target, dose to the skin and to other very superficial tissues tends to be higher than that of megavoltage x-rays. The methods presented here, namely, "interleaved carbon minibeams" and "radiosurgery with arrays of proton and light ion minibeams," both utilize beams segmented into arrays of parallel "minibeams" of about 0.3 mm incident-beam size. These minibeam arrays spare tissues, as demonstrated by synchrotron x-ray experiments. An additional feature of particle minibeams is their gradual broadening due to multiple Coulomb scattering as they penetrate tissues. In the case of interleaved carbon minibeams, which do not broaden much, two arrays of planar carbon minibeams that remain parallel at target depth, are aimed at the target from 90° angles and made to "interleave" at the target to produce a solid radiation field within the target. As a result, the surrounding tissues are exposed only to individual carbon minibeam arrays and are therefore spared. The method was used in four-directional geometry at the NASA Space Radiation Laboratory to ablate a 6.5-mm target in a rabbit brain at a single exposure with 40 Gy physical absorbed dose. Contrast-enhanced magnetic resonance imaging and histology 6-month later showed very focal target necrosis with nearly no damage to the surrounding brain. As for minibeams of protons and light ions, for which the minibeam broadening is substantial, measurements at MD Anderson Cancer Center in Houston, TX, USA; and Monte Carlo simulations showed that the broadening minibeams will merge with their neighbors at a certain tissue depth to produce a solid beam to treat the target. The resulting sparing of proximal normal tissue allows radiosurgical ablative treatments with smaller impact on the skin and shallow tissues. This report describes these two methods and discusses their potential clinical applications. [ABSTRACT FROM AUTHOR]

Symptomatic coronary artery disease is routinely treated with angioplasty and stenting. Unfortunately, treatment failure in the form of in-stent restenosis (ISR) occurs relatively frequently. Intravascular brachytherapy (IVBT) is a safe and effective method proven to markedly reduce the rate of ISR in native coronary arteries. The commercially available devices for IVBT are not FDA-approved for treatment of saphenous vein grafts (SVG). This article presents calculated dosimetry for treatment of a wide range of SVG, in addition to further evaluating the dose homogeneity for native coronary arteries.AAPM Task Group 43 and 60 formalisms permitted dose calculations for a wide range of vessel internal diameters (φ) in both native coronary arteries and SVG. Doses were analytically calculated for the Novoste Beta-Cath 5.0 French (F) treatment devices (30, 40, and 60 mm sourcetrains) when employed for the treatment of native vessels with 2.7 φ  4.0 mm and for SVG with 2.0  φ  5.0 mm. This latter range of φ was segmented into 7 bins to facilitate rapid clinical implementation with minimal errors. Calculations of dose and dose rate for the 3.5 F devices were also performed. Dose inhomogeneity in the form of dose maxima and minima were calculated for the 3.5 and 5.0 F catheters, with the 30, 40, and 60 mm sourcetrains, and for 2.0  φ  5.0 mm.The calculated doses rates for the 30 mm device were in agreement (typically ±0.3%) with measured dose rates. Reference dose calculations performed for SVG with 2.0  φ  5.0 mm were in alignment with those used for the more narrow range of native coronary arteries currently approved for IVBT. Errors associated with using a φ binning technique for simplifying clinical implementation did not exceed 15%, and were typically under 9%. The degree of dose inhomogeneity at a depth of 0.5 mm increased as φ increased, catheter size decreased, and sourcetrain length decreased, and was -42% and +101% relative to the prescribed dose for the 40 mm 5.0 F system with φ=4.0 mm.Use of 7 φ bins facilitates rapid clinical implementation of IVBT in the typical cardiac catheterization laboratory. While calculation of reference dose for treatment of large vessels is possible with established formalisms, the degree of dose inhomogeneity in light of current clinical results suggests further research is needed. [Copyright &y& Elsevier]

Abstract: Purpose: To compare overall survival, local and distant failure rates, ocular toxicity, and vision preservation in patients treated with eye plaque brachytherapy at Tufts Medical Center with those in the published literature. Methods and Materials: Records were reviewed for 53 patients with the diagnosis of uveal melanoma treated with plaque brachytherapy at Tufts Medical Center over the past 17 years. American Joint Committee on Cancer staging (T1, T2, or T3) were 4, 39, and 10 patients, respectively. All the patients were treated using 125I (n =37), 103Pd (n =5), or 131Cs (n =11) to a dose of 85Gy (documented as 100Gy before 1996 for the same physical dose). Results: With a mean followup of 75 months, 38 of 53 patients were still alive. Five patients (all 125I) developed liver metastases (9%) with no evidence of local failure. There were 10 definitive local failures and four additional transpupillary thermo-therapy procedures performed to ensure local control for lesions slow to respond. Twelve patients (23%) required enucleation. At most recent followup, 32 patients (71%) maintained 20/200 vision or better in the treated eye. In this first report of 131Cs plaque therapy with a mean followup of 20 months, there were two transpupillary thermo-therapy procedures and one definitive failure requiring enucleation after 10 months. Conclusions: Our disease control and ocular results were comparable to those in the literature given the extended followup. We are developing a multi-institutional, prospective clinical protocol for considering radionuclide selection and other prescriptive criteria. [Copyright &y& Elsevier]

Background: The incidence of bilateral trigeminal neuralgia (TN) is 1-6% of total number of TN cases. Gamma Knife Radiosurgery (GKRS) is effective in treating unilateral TN; however, outcomes of bilateral TN treated by GKRS have not been well evaluated. The purpose of this study is to evaluate the long-term GKRS outcomes of bilateral TN at our institution and compare with our published treatment outcomes of unilateral TN., Methods: Between 2000 and 2006, eight patients with bilateral TN were treated with GKRS. Data available on seven patients were collected. Facial pain outcomes were defined using the Barrow Neurological Institute pain intensity scale. Outcomes and toxicities were compared to published outcomes of unilateral TN patients treated with GKRS at our institution., Results: The incidence of bilateral TN in our series is 2.3%. Treatment outcomes were excellent in 5/14, good in 1/14, and poor in 8/14. Median follow-up time was 58 months. Median time-to-failure was 38 months. Pain control rate was 80% at 12 months and 65% at 36 months. Bothersome side effects were seen in 4/14 nerves treated. Compared with our long-term unilateral TN cohort, there was no statistically significant difference in outcome, time-to-failure, or rate of toxicity., Conclusion: Bilateral TN is rare, and effective treatment is crucial to improve the quality of life of those afflicted. Salvage GKRS is a reasonable treatment modality for individuals with bilateral TN.

Treatment of in-stent restenosis using intravascular brachytherapy (IVBT) has been demonstrated to be successful and has become the standard of care for native coronary artery disease. Based on the current Food and Drug Administration (FDA) indications for use and the clinical demand to increase the scope of this form of therapy to include saphenous vein grafts for the Beta-Cath System (Novoste Corporation, Norcross, Georgia), we set out to obtain institutional approval for off-label use. Identification of institutional regulatory bodies and related procedures for obtaining off-label device use was performed. Additionally, the IVBT written directive proscription and patient informed consent forms were revised to accurately administer radiation dose and to disclose the regulatory status of using IVBT for this anatomic site. While the specifics are outlined in this report, this process and the resources needed to obtain institutional approval for off-label use are indicative of that to be expected at similar institutions.