Initial Clinical Outcomes of a Phase II Trial of Focal Salvage LDR Brachytherapy for Local Recurrence of Prostate Cancer after External Beam Radiation Therapy

PURPOSE/OBJECTIVE(S)

To evaluate the clinical outcomes of focal salvage low dose rate brachytherapy (FSB) for biopsy proven local recurrence of prostate cancer after definitive external beam radiation therapy (EBRT).

MATERIALS/METHODS

Patients with a Phoenix definition PSA recurrence (nadir + 2.0ng/dL) after definitive EBRT for localized prostate cancer and a negative metastatic work up were enrolled in a Phase II clinical trial. Patients first underwent MR-guided transperineal mapping biopsy of the prostate using a template grid. Patients with a pathologically confirmed recurrence underwent FSB using iodine-125 seeds to a prescription dose of 145 Gy. The brachytherapy planning target volume (PTV) was defined by the positions of the pathologically negative core biopsies adjacent to the positive core biopsies as recorded on the template grid during the biopsy procedure. An intraoperative treatment plan was then developed to cover the PTV with the 145 Gy isodose line. Follow up included assessment of genitourinary (GU) and gastrointestinal (GI) toxicities using Common Terminology Criteria for Adverse Events version 4.03 (CTCAEv4.03), patient reported outcomes using the International Prostate Symptom Score (IPSS) and Expanded Prostate Cancer Index-26 (EPIC-26) forms, and serial PSA blood draws.

RESULTS

Ten patients underwent FSB. The median prior EBRT dose was 7805 cGy (interquartile range IQR 7560-7920) and the median time from completion of EBRT to FSB was 81 months (IQR 68-134). The median PSA prior to FSB was 3.2 ng/dL (IQR 2.3 - 4.5). The median follow up after FSB was 32 months (IQR 18-57). Eight patients were free of Phoenix definition PSA failure at last follow up. Of the two patients who experienced a PSA failure, one developed distant metastases 5 months after FSB and the other a biopsy proven seminal vesicle recurrence 3 years after FSB. The median change in post FSB IPSS score compared to the pre-FSB IPSS score was an increase of 1.5 (IQR -1.5 to 8) at 3 month follow up and an increase of 3.5 (IQR 0.5 to 5.5) at last follow up (≥1 year). The median change in post FSB EPIC-26 urinary domain score compared to the pre-FSB score was -1 (IQR -26 to +14.5) at 3 month follow up and +2 (IQR -12.5 to +14.5) at last follow up (≥1 year). The median change in post FSB EPIC-26 bowel domain score compared to the pre-FSB score was -2 (IQR -9.5 to 0.0) at 3 month follow up and 0 (IQR -6.0 to +3.0) at last follow up (≥1 year). No patients experienced post FSB Grade 3 or higher GU or GI toxicities.

CONCLUSION

High dose FSB for a local recurrence of prostate cancer after EBRT can be delivered with good biochemical control and a favorable toxicity profile. Further clinical trial enrollment and longer follow up will be needed to better assess long term outcomes.

Primary versus trauma-induced Gorham-Stout disease

Gorham-Stout disease - also known as "disappearing bone disease" is currently considered a single entity with varying clinical manifestations. We reviewed the existent literature from the earliest historic description(Jackson in 1838) and Gorham and Stout's original series of patients, multiple case reports and series since. After analyzing 212 reported cases, we identified 76 cases with details that recorded either a history of multifocal disease or an identifiable history of preceding trauma. From this review, we have defined two distinct Gorham-Stout entities - those characteristically associated with lymphangiomatosis [a form of GLA (generalized lymphangiomatosis) questionably distinguishable by bone biopsy and radiologic appearance] with multifocal distributed bone lesions, and those others, usually self-limited, first appearing after a traumatic event and always confined to a single bone or closely adjacent one. Multifocal disease is more likely to have chylothorax as a complication. These two Gorham-Stout entities differ in their demographic distribution, clinical history and manifestations, and they follow divergent clinical courses. The prognosis differs, and so should approaches to monitoring as well as acute and long-term treatment. Further research should seek to identify and define the differences in pathology and molecular mechanisms.

Slip! Slop! Slap! and SunSmart, 1980-2000: Skin cancer control and 20 years of population-based campaigning

The Anti-Cancer Council of Victoria has been running sun protection programs for more than 20 years: Slip! Slop! Slap! from 1980 to 1988 and SunSmart from 1988 to the present. The Victorian Health Promotion Foundation has provided funding for the SunSmart program for the past 13 years. These programs have played an important role in changing the whole society's approach to the sun and have resulted in marked reductions in sun exposure. This article describes the social, political, economic, and organizational context within which these programs developed. Then 10 areas are discussed that illustrate a critical aspect of the development and implementation of this successful systemwide health promotion program. These areas focus on key aspects of the context within which the program operates and on issues that derive from the experience of implementing program strategies. In summary, the success of the two programs is described as having been built on two key foundations: the vital integration of research and evaluation, on one hand, and a strong basis of consistency and continuity, on the other.

Hrs interacts with SNAP-25 and regulates Ca(2+)-dependent exocytosis

Synaptosome-associated protein of 25 kDa (SNAP-25) is a neuronal membrane protein essential for synaptic vesicle exocytosis. To investigate the mechanisms by which SNAP-25 mediates neurosecretion, we performed a search for proteins that interact with SNAP-25 using a yeast two-hybrid screen. Here, we report the isolation and characterization of a SNAP-25-interacting protein that is the rat homologue of mouse hepatocyte growth factor-regulated tyrosine kinase substrate (Hrs). Hrs specifically interacts with SNAP-25, but not SNAP-23/syndet. The association of Hrs and SNAP-25 is mediated via coiled-coil interactions. Using an Hrs-specific antibody, we have shown that Hrs is highly enriched in brain, where it codistributes with SNAP-25 in most brain regions. Subcellular fractionation studies demonstrate that in brain, Hrs exists in both cytosolic and membrane-associated pools. Studies using indirect immunofluorescence and confocal microscopy reveal that, in addition to early endosomes, Hrs is also localized to large dense-core secretory granules and synaptic-like microvesicles in nerve growth factor-differentiated PC12 cells. Moreover, overexpression of Hrs in PC12 cells inhibits Ca(2+)-dependent exocytosis. These results suggest that Hrs is involved in regulation of neurosecretion through interaction with SNAP-25.

Influence of dosing vehicles on the preclinical pharmacokinetics of phenolic antioxidants

Phenolic antioxidants, such as butylated hydroxyanisole (BHA) and propyl gallate (PG), have demonstrated paradoxical cancer initiating and preventive actions in animals. Studies examining the disposition and biological effects of these agents have used solutions in ethanol-saline, PEG400-saline, corn oil, or DMSO. The aim of this study was to compare the pharmacokinetics of BHA and PG in mice following dosing in either a "control" dosing vehicle (ethanol-saline, 2:3) or a solution of an inclusion complex of each agent with hydroxypropyl-beta-cyclodextrin (HPB) in saline. Results demonstrate that BHA or PG are rapidly absorbed and eliminated in mice following i.p. or p.o. dosing in either dosing vehicle. Pharmacokinetic parameters of BHA estimated in mice correlated with those reported for other species, including humans ("Interspecies Scaling"), suggesting that exposures are proportional to body weight across species. Therefore, rodents are appropriate animal models to study these phenolic antioxidants. The oral absorption of PG was influenced by dosing vehicle in mice, suggesting the need for cautious selection of traditional nonaqueous vehicles (such as DMSO, ethanol, etc.) in the investigation of biological activities of these xenobiotics. Indeed, DMSO elevated plasma alanine aminotransferase (ALT) and alkaline phosphatase (ALP) concentrations following subchronic i.p. administration of various blank vehicles to mice. Such elevations in plasma concentrations of these enzymes are considered biomarkers of hepatotoxicity. The absolute oral bioavailability of PG (administered as an HPB complex) in rats was low (5%) suggesting extensive metabolism or incomplete absorption. The low oral bioavailability of these phenolic antioxidants in rodents suggests that the risk assessment of these antioxidants should include an evaluation of their metabolites as well.

Cognitive strategy instruction in mathematics for students with learning disabilities

This article provides a context for understanding and using cognitive strategy instruction to improve students' performance in mathematics. The theoretical and research base for strategy instruction is reviewed, and characteristics of students who have difficulties in mathematics are discussed from a developmental perspective. Then, a practical illustration of cognitive strategy instruction used to assess the teach mathematical problem solving to middle school students with learning disabilities is presented.

Construction and analysis of linking libraries from the mouse X chromosome

A hybrid cell line containing the mouse X chromosome on a human background has been used to construct linking libraries from the mouse X chromosome, and approximately 250 unique EagI and NotI clones have been identified. Seventy-three clones have been sublocalized onto the X chromosome using interspecific Mus spretus/Mus domesticus crosses and a panel of somatic cell hybrids carrying one-half of reciprocal X-autosome translocations. The average spacing of the linking clones mapped to date is about one every 2 Mb of DNA. Two clones from the central region of the chromosome have been physically linked by pulsed-field gel electrophoresis. A large number of clones contain conserved sequences, indicating the presence of CpG-rich island-associated genes. The clones isolated from these libraries provide a valuable resource for comparative mapping between man and mouse X chromosomes, isolation of X-linked disease loci of interest by reverse genetics, and analysis of the long-range structure and organization of the chromosome.