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Purpose: To report an update of our previous experience using stereotactic body radiation therapy (SBRT) for the primary treatment of prostate cancer, risk stratified by the updated National Comprehensive Cancer Network (NCCN) version 2.2014, reporting efficacy and toxicity in a community hospital setting., Methods: From 2007 to 2012, 142 localized prostate cancer patients were treated with SBRT using CyberKnife. NCCN guidelines Version 2.2014 risk groups analyzed included very low (20%), low (23%), intermediate (35%), and high (22%) risk. To further explore group heterogeneity and to comply with new guidelines, we separated our prior intermediate risk group into favorable intermediate and unfavorable intermediate groups depending on how many intermediate risk factors were present (one vs. > one). The unfavorable intermediate group was further analyzed in combination with the high risk group as per NCCN guidelines Version 2.2014. Various dose levels were used over the years of treatment, and have been categorized into low dose (35 Gy, n = 5 or 36.25 Gy, n = 107) and high dose (37.5 Gy, n = 30). All treatments were delivered in five fractions. Toxicity was assessed using radiation therapy oncology group criteria., Results: Five-year actuarial freedom from biochemical failure (FFBF) was 100, 91.7, 95.2, 90.0, and 86.7% for very low, low, intermediate and high risk patients, respectively. A significant difference in 5 year FFBF was noted for patients with Gleason score (GS) ≥8 vs. 7 vs. 5/6 (p = 0.03) and low vs. high dose (p = 0.05). T-stage, pretreatment PSA, age, risk stratification group, and use of ADT did not affect 5-year FFBF. Multivariate analysis revealed GS and dose to be the most predictive factors for 5-year FFBF., Conclusion: Our experience with SBRT for the primary treatment of localized prostate cancer demonstrates favorable efficacy and toxicity comparable to the results reported for IMRT in literature. GS remains the single most important pretreatment predictor of outcome.

Unlabelled: The internalizing properties of murine antibody 17-1A in human colon cancer cells make it attractive as a carrier for radionuclides with short range emissions such as 125I. Murine 17-1A IgG2a antibody, which reacts against human gastrointestinal cancers, has been chimerized by joining its variable region with human IgG1 k constant region. A pilot clinical trial of increasing doses of 125I-chimeric 17-1A in patients with metastatic colorectal cancer has been conducted., Methods: Patients were treated in groups of 2-4; 2 patients at Hahnemann University and 26 at the University of Alabama at Birmingham. Groups 1-5 received single administrations with 125I doses of 20, 40, 60, 80 or 100 mCi. Subsequent groups received therapeutic doses of 150, 200 or 250 mCi, with the dose subdivided into infusing of 50 or 100 mCi at 4-day intervals. All treatments were delivered in an outpatient setting using radiation precautions. Labeling at 10 mCi/mg antibody was performed on the day of treatment., Results: Pharmocokinetics of circulating antibody was studied for initial patients, showing alpha T 1/2 of 17-27 hr and beta T 1/2 of 100-190 hr. Whole-body T 1/2 of radioactivity was determined by measuring urinary excretion or gamma emissions. Treatment was well tolerated without significant acute or late side effects. No significant bone marrow suppression or other dose-limiting toxicities were noted over this dose range. No objective responses were noted., Conclusion: These results show that high-dose outpatient radioimmunotherapy with an 125I-labeled internalizing antibody can be achieved without significant patient toxicity or radiation hazard.

We present the findings on iodine-131 (131I) scintigraphy, thallium-201 (201Tl) scintigraphy and quantitative thyroglobulin (QTG) estimation in two patients with follicular carcinoma of the thyroid with extensive metastases. The lesions were initially seen on 131I scintigraphs, but were not subsequently visualized with scanning doses of 131I (5 mCi), while retaining their ability to produce increasing amounts of thyroglobulin and take up 201Tl. Implications in choosing the appropriate diagnostic tests in the management of differentiated thyroid cancer are discussed.

The present report elucidates the movement of 201Tl through the cerebrospinal fluid compartment and its subsequent uptake by normal brain. Autoradiographic studies of rat brain, after stereotaxic 201Tl injection into either the lateral or fourth ventricle, reveal that 201Tl moves freely through the cerebrospinal and extracellular fluid compartments. Subsequent to lateral ventricular injection, central thalamic and specific hypothalamic nuclei are heavily labeled. Densely labeled mesencephalic nuclei include the periaqueductal grey and oculomotor nuclear complex. Labeling of giant cells within the vestibular complex is suggestive of neuronal uptake. Major fiber tracts are devoid of label confirming that 201Tl uptake does not occur in white matter. Most labeling following fourth ventricle injection occurs within the caudal medulla and cervical spinal grey. Our findings suggest that 201Tl uptake by normal brain from the cerebrospinal fluid occurs as a function of thallium concentration and neuronal activity.

Malignant soft-tissue neoplasms may be demonstrated in the course of triple-phase skeletal scintigraphy due to the presence of either abnormal vascularity or calcifications. We report the unusual case of a malignant lymphoma which was detected in the vascular phases of a triple-phase skeletal scintigraphic study but was not visualized utilizing conventional radioangiographic techniques. Lymphoma should be included in the differential diagnosis of soft-tissue neoplasms demonstrable by scintiangiography.

Radiation oncologists have contributed greatly to the improved quality of care of the cancer patient; this has been shown repeatedly in various reports. The improvements in quality have been achieved because of a greater understanding of the natural history of cancer and a more critical evaluation of the results of clinical treatment. Increasing numbers of physicians involved in radiation oncology are participating in clinical evaluation and in multimodal programs of treatment. Major areas for future research in radiation oncology have been identified. The radiation oncologist is now a fully integrated member of the multidisciplinary cancer team participating in clinical treatment and in national cooperative clinical trials. The radiation oncologist's active participation in multidisciplinary clinical treatment programs is significantly changing the character of cancer management. Integration of new techniques of treatment, new combined programs, and greater emphasis on the efficacies of single treatment programs offer major opportunities to cure many cancers that were previously considered incurable.

5-thio-D-glucose (5-TDG) exerts profound effects on rapidly metabolizing tissues. We have used liquid scintillation counting to study the tissue distribution and pharmacokinetics of S-35-labeled 5-TDG in hamster models of pancreatic tumors. In the normal hamster, initial uptake of S-35 activity into kidney, liver, and blood was high, but rapidly decreased with time. The pancreatic uptake (% dose/g) never exceeded 0.75%. This level occurred only at the earliest times after administration. Uptake in all three tumor models exceeded that in pancreatic tissue within 15 min of injection. The highest tumor-to-pancreas ratio was seen in the duct-tumor model, which also exhibited the most favorable tumor-to-tissue ratio when compared with kidney, liver and muscle. Favorable ratios were most pronounced at 6 and 24 hr after injection. These studies provide impetus for the use of 5-TDG as a model compound for the synthesis of potentially useful agents for clinical detection of pancreatic tumors.