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OBJECTIVES: To estimate the rates of rectal bleeding after dose-escalated three-dimensional conformal radiation therapy (3D-CRT) on a prospective, Phase II study in which a modified intrarectal balloon was used for prostate gland localization and immobilization. METHODS: The study cohort comprised 100 men with biopsy-proven adenocarcinoma of the prostate and at least one high-risk feature (prostate-specific antigen level greater than 10 ng/mL, Gleason score 7 or higher, or clinical or radiographic T3 disease). Treatment consisted of androgen suppression therapy and four-field 3D-CRT with an intrarectal balloon for the initial 15 treatments. Planning treatment volume dose was 75.6 Gy. The primary endpoint of time to grade 3 rectal bleeding was estimated with the Kaplan-Meier method for 57 men with a minimum follow-up of 1 year. RESULTS: For 57 men with a median (range) follow-up of 1.8 (1.0 to 3.3) years, the median (range) volume of rectum exceeding 70 Gy was 3.7 (0.6 to 14.7) cm3, and the 2-year estimate of grade 3 rectal bleeding rate was 10%. This rate was 100% as compared with 0 (P < 0.0001) for men who were taking warfarin (n = 3) or high-dose aspirin (n = 1) as compared with neither, respectively. All grade 3 rectal bleeding events were controlled with argon plasma coagulation. CONCLUSIONS: Dose-escalated 3D-CRT with an intrarectal balloon technique for prostate localization and immobilization produced no measurable grade 3 rectal bleeding unless the patient was taking anticoagulants.
The National Notifiable Disease Surveillance System received 1,076 tuberculosis (TB) notifications in 2004, of which 1,043 were new cases and 33 were relapses. The incidence of TB in Australia has remained at a stable rate since 1985 and was 5.4 cases per 100,000 population in 2004. The high-incidence groups remain people born overseas and Indigenous Australians at 21.7 and 8.1 cases per 100,000 population, respectively. By contrast, the incidence of TB in the non-Indigenous Australian-born population was 1.0 cases per 100,000 population. Comparison of the 2004 TB notification data against the performance indicators set by National Tuberculosis Advisory Committee highlights that enhanced TB control measures should be considered among these high-risk groups.
PURPOSE: We determined the acute gastrointestinal (GI), genitourinary (GU), and dermatologic (D) toxicity during dose-escalated three-dimensional conformal radiation therapy (3DCRT). A modified intrarectal balloon (Medrad) was used for prostate gland localization and immobilization. METHODS: Forty-six men with clinical category T1c to T3a, and at least one high-risk feature (PSA >10, Gleason > or =7, or MRI evidence of extracapsular extension or seminal vesical invasion) comprised the study cohort. Treatment consisted of hormonal therapy and 4-field 3DCRT using an intrarectal balloon for the initial 15 of 40 treatments. Planning treatment volume dose was 72 Gy (95% normalization). A Mantel-Haenzel Chi-square test compared the distribution of GU, GI, and D symptoms at baseline and at end of treatment (EOT). RESULTS: There was no significant difference between the 2 time points in the proportion of patients with bowel symptoms (p = 0.73), tenesmus (p = 0.27), nocturia (p = 1.00), or GU urgency (p = 0.40). However, there was a significant decrease in GU frequency (70% vs. 50%, p = 0.46) as a result of medical interventions and a significant increase in hemorrhoidal irritation (4% vs. 20%, p = 0.02) and anal cutaneous skin reaction (0% vs. 70%, p < 0.001). By 3 months after EOT compared to baseline, there was no significant difference in the proportion of patients experiencing hemorrhoidal bleeding (4% vs. 8%, p = 0.52), requiring intervention for hemorrhoidal symptoms (7% vs. 5%, p = 0.8), or experiencing persistent anal cutaneous skin reaction (0% vs. 3%, p = 0.31). CONCLUSION: Dose-escalated 3DCRT using an intrarectal balloon for prostate localization and immobilization was well tolerated. Acute GU, GI, and D symptoms resolved with standard dietary or medical interventions by the EOT or shortly thereafter.
OBJECTIVES: To evaluate the risk of acute urinary retention (AUR) and sequelae after urethra-sparing magnetic resonance imaging (MRI)-guided prostate brachytherapy. METHODS: Between 1997 and 2003, MRI-guided prostate brachytherapy was performed after external beam radiotherapy (n = 60) or as monotherapy (n = 188) following a diagnosis of low-risk prostate adenocarcinoma. The median prostate gland volume was 40 cm3 (range 16 to 184). Of the 248 patients, 88 (35%) had prostate gland volumes greater than 45 cm3. The median follow-up was 40 months. RESULTS: Of the 248 patients, 18 (7%) developed AUR. Of the 248 patients, 2% (3 of 160), 6% (3 of 49), 28% (8 of 29), and 40% (4 of 10) of patients experienced AUR if the prostate gland volume was less than 45, 45 to 60, 60 to 90, or greater than 90 cm(3), respectively (P <0.0001). Retention requiring intermittent self-catheterization resolved in one half of the patients by 2 weeks and had resolved in all patients by 6 weeks. At 1, 3, and 6 months after implantation, 100%, 57%, and 29% of patients who experienced AUR, respectively, used Flomax (P <0.0001). The mean Flomax dose used decreased from 0.9 mg at 1 month to 0.53 mg at 1 year. CONCLUSIONS: AUR after urethral-sparing MRI-guided prostate brachytherapy is volume dependent and is self-limited despite very large prostate gland volumes.
OBJECTIVES: To determine whether pretreatment risk groups also predict for posttreatment prostate-specific antigen (PSA) doubling times (PSADTs). Pretreatment risk groups predict for posttreatment biochemical failure (BF) after conformal radiotherapy in patients with prostate cancer and posttreatment PSADTs can predict for prostate cancer-related deaths. METHODS: The study cohort consisted of 416 patients with clinically localized prostate cancer treated with conformal radiotherapy between 1989 and 2001. The patients were divided into low, intermediate, and high-risk groups. BF was defined using the American Society for Therapeutic Radiology and Oncology consensus definition. Patients with BF were grouped according to their PSADT (3 months or less, longer than 3 months to less than 6 months, 6 months to less than 12 months, and 12 months or longer). A Mantle-Haenszel chi-square metric tested for an association between the pretreatment risk group and the PSADT. Logistic regression multivariate analysis was performed to evaluate whether the pretreatment risk group predicted the PSADT. RESULTS: Of the 416 patients, 96 (23%), 194 (47%), and 126 (30%) were categorized as low, intermediate, and high risk, respectively. A total of 92 patients (22%) experienced BF. Of these 92 patients, the PSADT was 3 months or less in 6 (7%), longer than 3 months to less than 6 months in 13 (14%), 6 months to less than 12 months in 35 (36%), and 12 months or longer in 38 (41%). The pretreatment risk group correlated significantly with the PSADT (P = 0.026). Logistic regression analysis revealed that intermediate and high-risk disease was significantly associated with shorter PSADTs (P = 0.039). CONCLUSIONS: A significant association between the pretreatment risk group and posttreatment PSADT was demonstrated. Use of this selection criterion at diagnosis for more aggressive treatment appears warranted.
PURPOSE: We investigated whether pretreatment factors predicted time to prostate cancer-specific mortality (PCSM) after conventional-dose and conformal radiation therapy (CRT). PATIENTS AND METHODS: Between 1988 and 2002, 421 patients with low (prostate-specific antigen [PSA] level < or = 10 ng/mL and biopsy Gleason score < or = 6) or favorable intermediate-risk (PSA > 10 to 15 ng/mL or biopsy Gleason score 3 + 4, but not both factors) disease underwent CRT (median dose, 70.4 Gy). Cox regression multivariable analysis was performed to determine whether the PSA level, Gleason score, T category, or the percentage of positive cores (% PC) predicted time to PCSM after CRT. After a median follow-up of 4.5 years, 117 (28%) patients have died. RESULTS: The % PC was the only significant predictor (Cox P < or =.03). The relative risk of PCSM after CRT for patients with > or = 50% as compared with less than 50% PC was 10.4 (95% CI, 1.2 to 87; Cox P =.03), 6.1 (95% CI, 1.3 to 28.6; Cox P =.02), and 12.5 (95% CI, 1.5 to 107; Cox P =.02) in men with a PSA < or = 10 and Gleason score < or = 6, PSA < or = 10 and Gleason score < or = 7, and PSA < or = 15 and Gleason score < or = 6, respectively. By 5 years after CRT, 5% to 9% compared with less than 1% (log-rank P < or =.01) of these patients experienced PCSM if they had > or = 50% compared with less than 50% PC, respectively. CONCLUSION: CRT dose-escalation techniques, the addition of hormonal therapy, or both should be considered in the management of patients with low or favorable intermediate-risk disease and > or = 50% PC.
The National Notifiable Disease Surveillance System (NNDSS) received 982 tuberculosis (TB) notifications in 2003, of which 947 were new cases, 33 were relapses and two were cases with unknown history. The incidence of TB in Australia has remained at a stable rate since 1985 and was 4.9 cases per 100,000 population in 2003. The high-incidence groups remain people born overseas and Indigenous Australians at 19.9 and 8.7 cases per 100,000 population, respectively. By contrast the incidence in non-Indigenous Australians was 0.9 per 100,000. Comparison of the 2003 TB notification data against the performance indicators set by National Tuberculosis Advisory Committee highlights that enhanced TB control measures should be considered among these high-risk groups.
The deposition of a 30-A-thick layer of iridium upon a 250-A-thick osmium reflective layer for use as a diffraction grating in the Cosmic Hot Interstellar Plasma Spectrometer (CHIPS) satellite observatory has provided sufficient protection from an expected maximum orbital atomic-oxygen fluence of 1 x 10(16) atoms/cm2. The grating parameters of groove constant and depth, efficiencies of zeroth-order, first and second inside orders, and first inside-order efficiency positional uniformity as well as stray light near the first inside order of the Ir-Os-coated grating were measured within a CHIPS spectral bandpass of 90-260 A. Stray-light measurements were also made near the first inside spectral order at 304, 584, and 1216 A. The results make the Ir-Os coat an acceptable grating reflectivity layer for CHIPS and other spaceborne extreme-ultraviolet spectrometers that employ grazing-incidence reflection optics.
OBJECTIVES: To determine whether high-dose radiation delivered to a subvolume of the prostate gland (peripheral zone) using intraoperative magnetic resonance imaging-guided brachytherapy provided comparable 5-year prostate-specific antigen (PSA) control rates to radical prostatectomy (RP) in select patients compared prospectively but in a nonrandomized setting. METHODS: Between 1997 and 2002, 322 and 196 patients with clinical Stage T1c, PSA less than 10 ng/mL, biopsy Gleason score 3 + 4 or less, and without perineural invasion underwent RP or intraoperative magnetic resonance imaging-guided brachytherapy, respectively, and had a 2-year minimal follow-up. Cox regression multivariable analysis was used to evaluate whether the initial therapy, pretreatment PSA level, biopsy Gleason score, percentage of positive biopsies, or prostate gland volume were predictors of the time to post-therapy PSA failure. PSA failure was estimated using the Kaplan-Meier method and defined using the American Society for Therapeutic Radiology Oncology consensus definition. RESULTS: Only the percentage of positive prostate biopsies (P(Cox) = 0.02) was a significant predictor of the time to post-treatment PSA failure. However, the distribution of this parameter between RP and brachytherapy-treated patients was not significantly different (P(chi-square) = 0.25). The initial therapy did not predict for the time to post-therapy PSA failure (P(Cox) = 0.18). The 5-year estimate of PSA control was 93% versus 95% (P(log-rank) = 0.16) for the RP and brachytherapy patients, respectively. CONCLUSIONS: Despite only partial prostatic irradiation using intraoperative magnetic resonance imaging-guided brachytherapy, similar 5-year estimates of PSA control were found for both brachytherapy and RP-managed patients.
In 2002, there were 1,028 cases of tuberculosis (TB) reported to the National Notifiable Disease Surveillance System, of which 997 were new cases, 30 were relapses and 1 unknown. The incidence rate of TB in Australia in 2002 was 5.2 cases per 100,000 population. The highest incidence of TB was reported in people born overseas (20.2 cases per 100,000 population), followed by Indigenous Australians (8.5 cases per 100,000 population). By contrast, the incidence rate of TB in the nonIndigenous Australian-born population was 1.1 cases per 100,000 population. This pattern of TB incidence rates amongst the sub-populations of Australia has been observed for over 10 years. The rates were evaluated against the performance indicators set by the National Tuberculosis Advisory Committee to ensure that Australia's record of TB control is maintained and improved.
The design and calibration of thin-film Zr transmission filters for the Cosmic Hot Interstellar Plasma Spectrometer (CHIPS) spaceborne astronomical telescope is presented. The transmission of a 1,000-A-thick Zr filter is measured for wavelengths from 45 to 1,304 A as well as its variability with respect to expected space-flight enviromental extremes of temperature, vibration, and atomic O bombardment. For the CHIPS spectral band of 90-260 A, the transmission of the Zr fiter is deemed useful between 90 and 200 A and is stable with respect to expected temperature and vibrational changes. The maximum atomic O bombardment decreases the filter transmission between 90 and 130 A by approximately 20% and does not appreciably affect the rest of the CHIPS bandpass. These results make Zr an acceptable filter candidate for CHIPS.
STUDY OBJECTIVES: The contribution of atopy to childhood asthma has been debated. We aimed to examine the relationship between atopy and asthma, taking into account differences in respiratory symptoms and disease severity. DESIGN: A cross-sectional asthma survey involving the following: (1) a population sample of 758 (81% of eligible) school children aged 8 to 10 years from randomly selected schools in the Australian Capital Territory in 1999, and (2) a hospital-based sample of 78 (70% of eligible) children attending the hospital for asthma. Skin-prick test results to 10 common aeroallergens were available on 722 children and 77 children, respectively. Baseline spirometry was obtained on a subset of school children (n = 515, 78% of eligible). RESULTS: The association between atopy and wheeze by wheeze frequency over the past year was as follows: no episodes (odds ratio [OR], 1.00 [reference]), 1 to 3 episodes (OR, 3.27; 95% confidence interval [CI], 2.15 to 4.97), 4 to 12 episodes (OR, 3.44; 95% CI, 1.75 to 6.75), and > 12 episodes (OR, 8.70; 95% CI, 3.07 to 24.55), with a higher population attributable fraction (PAF) for > 12 episodes (75%) than 1 to 3 episodes (49%). Atopy was moderately related to asthma ever (OR, 2.09; 95% CI, 1.52 to 2.85; PAF, 33%) but strongly related to 1999 hospital attendance for asthma (OR, 16.95; 95% CI, 6.76 to 42.48; PAF, 89%). Adjustment for child age, gas heater use, and maternal smoking near the child did not materially alter these findings. CONCLUSIONS: The clinical features of frequent wheeze or hospital asthma attendance are largely attributable to atopy, but infrequent wheeze or a history of asthma ever are not. Atopic children are overrepresented in the severe range of the asthma spectrum.
In 2001, there were 997 cases of tuberculosis (TB) reported to the National Notifiable Diseases Surveillance System, of which, 967 were new cases of TB and 30 cases were relapses. The incidence rate of TB in Australia in 2001 was 5.1 cases per 100,000 population. The highest incidence of TB was reported in people born overseas (19.3 cases per 100,000 population), followed by Indigenous Australians (9.8 cases per 100,000 population). In contrast, the incidence rate of TB in the non-Indigenous Australian-born population was 1.0 cases per 100,000 population. This pattern of TB incidence rates amongst the sub-populations of Australia has been observed for over 10 years. Eighty-six per cent of TB cases completed treatment in 2001. Treatment was unsuccessful in 7 cases and only 22 cases defaulted. The National Tuberculosis Advisory Committee has published a National Strategic Plan with performance indicators to ensure that this enviable record of TB control is maintained and improved.