Antibiotic utilisation and resistance over the first decade of nationally funded antimicrobial stewardship programmes in Singapore acute-care hospitals

OBJECTIVE

The aim of this study was to describe the time series of broad-spectrum antibiotic utilisation and incidence of antibiotic-resistant organisms during the implementation of antimicrobial stewardship programmes (ASP) in Singapore.

METHODS

An observational study was conducted using data from 2011 to 2020 in seven acute-care public hospitals. We applied joinpoint regressions to investigate changes in antibiotic utilisation rate and incidence density of antibiotic-resistant organisms.

RESULTS

Across the seven hospitals, quarterly broad-spectrum antibiotic utilisation rate remained stable. Half-yearly incidence density of antibiotic-resistant organisms with two joinpoints at first half (H1) of 2012 and second half (H2) of 2014 decreased significantly in the second and third period with a half-yearly percentage change (HPC) of -2.9% and - 0.5%, respectively. Across the five hospitals with complete data, half-yearly broad-spectrum antibiotic utilisation rate with one joinpoint decreased significantly from H1 of 2011 to H2 of 2018 (HPC - 4.0%) and H2 of 2018 to H2 2020 (HPC - 0.5%). Incidence density of antibiotic-resistant organisms decreased significantly in the two joinpoint periods from H1 of 2012 to H2 of 2014 (HPC - 2.7%) and H2 of 2014 to H2 of 2020 (HPC - 1.0%). Ceftriaxone with one joinpoint decreased significantly from H1 of 2011 to H1 of 2014 (HPC - 6.0%) and H1 of 2014 to H2 of 2020 (HPC - 1.8%) and ceftriaxone-resistant E. coli and K. pneumoniae decreased significantly in later periods, from H2 of 2016 to H2 of 2020 (HPC - 2.5%) and H1 of 2012 to H2 of 2015 (HPC - 4.6%) respectively. Anti-pseudomonal antibiotics with one joinpoint decreased significantly from H1 of 2011 to H2 of 2014 (HPC - 4.5%) and H2 of 2014 to H2 of 2020 (HPC - 0.8%) and that of quinolones with one joinpoint at H1 of 2015 decreased significantly in the first period. C. difficile with one joinpoint increased significantly from H1 of 2011 to H1 of 2015 (HPC 3.9%) and decreased significantly from H1 of 2015 to H2 of 2020 (HPC - 4.9%).

CONCLUSIONS

In the five hospitals with complete data, decrease in broad-spectrum antibiotic utilisation rate was followed by decrease in incidence density of antibiotic-resistant organisms. ASP should continue to be nationally funded as a key measure to combat antimicrobial resistance in acute care hospitals.

Protocol for a mixed-methods and multi-site assessment of the implementation process and outcomes of a new community-based frailty programme

Background

Frailty is increasing in prevalence internationally with population ageing. Frailty can be managed or even reversed through community-based interventions delivered by a multi-disciplinary team of professionals, but to varying degrees of success. However, many of these care models’ implementation insights are contextual and may not be applicable in different cultural contexts. The Geriatric Service Hub (GSH) is a novel frailty care model in Singapore that focuses on identifying and managing frailty in the community. It includes key components of frailty care such as comprehensive geriatric assessments, care coordination and the assembly of a multi-disciplinary team. This study aims to gain insights into the factors influencing the development and implementation of the GSH. We also aim to determine the programme’s effectiveness through patient-reported health-related outcomes. Finally, we will conduct a healthcare utilisation and cost analysis using a propensity score-matched comparator group.

Methods

We will adopt a mixed-methods approach that includes a qualitative evaluation among key stakeholders and participants in the programme, through in-depth interviews and focus group discussions. The main topics covered include factors that affected the development and implementation of each programme, operations and other contextual factors that influenced implementation outcomes. The quantitative evaluation monitors each programme’s care process through quality indicators. It also includes a multiple-time point survey study to compare programme participants’ pre- and post- outcomes on patient engagement, healthcare services experiences, health status and quality of life, caregiver burden and societal costs. A retrospective cohort study will compare healthcare and cost utilisation between participants of the programme and a propensity score-matched comparator group.

Discussion

The GSH sites share a common goal to increase the accessibility of essential services to frail older adults and provide comprehensive care. This evaluation study will provide invaluable insights into both the process and outcomes of the GSH and inform the design of similar programmes targeting frail older adults.

Trial Registration

ClinicalTrials.gov Identifier NCT04866316. Date of Registration April 26, 2021. Retrospectively registered.

Stranded seed displacement, migration, and loss after permanent prostate brachytherapy as estimated by Day 0 fluoroscopy and 4-month postimplant pelvic x-ray

PURPOSE

The aim of the study was to determine the incidence of local displacement, distant seed migration to the chest, and seed loss after permanent prostate brachytherapy (PPB) with stranded seeds (SSs) using sequential two-dimensional fluoroscopic pelvic and chest x-rays.

METHODS AND MATERIALS

Between October 2010 and April 2014, a total of 137 patients underwent PPB and 4-month followup pelvic and chest x-ray imaging. All patients had exclusively SSs placed and an immediate postimplant fluoroscopic image of the seed cluster. Followup x-ray images were evaluated for the number, location, and displacement of seeds in comparison to Day 0 fluoroscopic images. Significant seed displacement was defined as seed displacement >1 cm from the seed cluster. Followup chest x-rays were evaluated for seed migration to the chest.

RESULTS

Seed migration to the chest occurred in 3 of the 137 patients (2%). Seed loss occurred in 38 of the 137 patients (28%), with median loss of one seed (range, 1-16), and total seeds loss of 104 of 10,088 (1.0%) implanted. Local seed displacement was seen in 12 of the 137 patients (8.8%), and total seeds displaced were 0.15% (15/10,088).

CONCLUSIONS

SS placement in PPB is associated with low rates of substantial seed loss, local displacement, or migration to the chest. Comparing immediate postimplant fluoroscopic images to followup plain x-ray images is a straightforward method to supplement quality assurance in PPB and was found to be useful in identifying cases where seed loss was potentially of clinical significance.

Self-reported pain intensity with the numeric reporting scale in adult dengue

Background

Pain is a prominent feature of acute dengue as well as a clinical criterion in World Health Organization guidelines in diagnosing dengue. We conducted a prospective cohort study to compare levels of pain during acute dengue between different ethnicities and dengue severity.

Methods

Demographic, clinical and laboratory data were collected. Data on self-reported pain was collected using the 11-point Numerical Rating Scale. Generalized structural equation models were built to predict progression to severe disease.

Results

A total of 499 laboratory confirmed dengue patients were recruited in the Prospective Adult Dengue Study at Tan Tock Seng Hospital, Singapore. We found no statistically significant differences between pain score with age, gender, ethnicity or the presence of co-morbidity. Pain score was not predictive of dengue severity but highly correlated to patients’ day of illness. Prevalence of abdominal pain in our cohort was 19%. There was no difference in abdominal pain score between grades of dengue severity.

Conclusion

Dengue is a painful disease. Patients suffer more pain at the earlier phase of illness. However, pain score cannot be used to predict a patient’s progression to severe disease.

Determinants of Health-Related Quality of Life (HRQoL) in the Multiethnic Singapore Population - A National Cohort Study

BACKGROUND

HRQoL is an important outcome to guide and promote healthcare. Clinical and socioeconomic factors may influence HRQoL according to ethnicity.

METHODOLOGY

A multiethnic cross-sectional national cohort (N = 7198) of the Singapore general population consisting of Chinese (N = 4873), Malay (N = 1167) and Indian (N = 1158) adults were evaluated using measures of HRQoL (SF-36 version 2), family functioning, health behaviours and clinical/laboratory assessments. Multiple regression analyses were performed to identify determinants of physical and mental HRQoL in the overall population and their potential differential effects by ethnicity. No a priori hypotheses were formulated so all interaction effects were explored.

PRINCIPAL FINDINGS

HRQoL levels differed between ethnic groups. Chinese respondents had higher physical HRQoL (PCS) than Indian and Malay participants (p<0.001) whereas mental HRQoL (MCS) was higher in Malay relative to Chinese participants (p<0.001). Regressions models explained 17.1% and 14.6% of variance in PCS and MCS respectively with comorbid burden, income and employment being associated with lower HRQoL. Age and family were associated only with MCS. The effects of gender, stroke and musculoskeletal conditions on PCS varied by ethnicity, suggesting non-uniform patterns of association for Chinese, Malay and Indian individuals.

CONCLUSIONS

Differences in HRQoL levels and determinants of HRQoL among ethnic groups underscore the need to better or differentially target population segments to promote well-being. More work is needed to explore HRQoL and wellness in relation to ethnicity.

Epigenetic state and expression of imprinted genes in umbilical cord correlates with growth parameters in human pregnancy

BACKGROUND

Genomic imprinting is a process causing genes to be expressed according to parental origin. Imprinting acts to coordinate fetal and prenatal growth, as well as control postnatal adaptations. Studies on human imprinting are confounded by tissue availability, sampling variability and limitations posed by tissue-specific expression and cellular heterogeneity within tissues. The human umbilical cord is an easily available, embryonic-derived fetal tissue with the potential to overcome many of these limitations.

METHODS

In a sensitive, gene-specific quantitative expression analysis, we show for the first time robust imprinted gene expression combined with methylation analysis in cords isolated from Asian Chinese full-term births.

RESULTS

Linear regression analyses revealed an inverse correlation between expression of pleckstrin homology-like domain, family A, member 2 (PHLDA2) with birth weight (BW). Furthermore, we observed significant down-regulation of the paternally expressed gene 10 (PEG10) in low BW babies compared to optimum BW babies. This change in PEG10 gene expression was accompanied by concomitant methylation alterations at the PEG10 promoter.

CONCLUSIONS

These data are the first to demonstrate relative expression of an imprinted gene associated with epigenetic changes in non-syndromic fetal growth restriction in babies. They show that perturbed expression in compromised fetal growth may be associated with in utero modulation of the epigenetic state at the imprinting control regions and implicate specific imprinted genes as new biomarkers of fetal growth.

Preliminary buprenorphine sublingual tablet pharmacokinetic data in plasma, oral fluid, and sweat during treatment of opioid-dependent pregnant women

BACKGROUND

Buprenorphine is currently under investigation as a pharmacotherapy to treat pregnant women for opioid dependence. This research evaluates buprenorphine (BUP), norbuprenophine (NBUP), buprenorphine-glucuronide (BUP-Gluc), and norbuprenorphine-glucuronide (NBUP-Gluc) pharmacokinetics after high-dose (14-20 mg) BUP sublingual tablet administration in three opioid-dependent pregnant women.

METHODS

Oral fluid and sweat specimens were collected in addition to plasma specimens for 24 hours during gestation weeks 28 or 29 and 34, and 2 months after delivery. Time to maximum concentration was not affected by pregnancy; however, BUP and NBUP maximum concentration and area under the curve at 0 to 24 hours tended to be lower during pregnancy compared with postpartum levels.

RESULTS

Statistically significant but weak positive correlations were found for BUP plasma and OF concentrations and BUP/NBUP ratios in plasma and oral fluid. Statistically significant negative correlations were observed for times of specimen collection and BUP and NBUP oral fluid/plasma ratios. BUP-Gluc and NBUP-Gluc were detected in only 5% of oral fluid specimens. In sweat, BUP and NBUP were detected in only four of 25 (12 or 24 hours) specimens in low concentrations (less than 2.4 ng/patch).

CONCLUSION

These preliminary data describe BUP and metabolite pharmacokinetics in pregnant women and suggest that, like methadone, upward dose adjustments may be needed with advancing gestation.

Multimodality therapy including surgical resection (SR) and intraoperative electron radiotherapy (IOERT) for locoregionally recurrent (LRR) or advanced primary malignancies of the urinary bladder (UB) or ureter

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Background: For patients (pts) with LRR or advanced primary tumors of the UB or ureter, limited therapeutic options exist. Outcomes of combined SR and IOERT are reported here.

Methods: From 1983 to 2009, a total of 17 pts with urothelial (16 pts) or squamous cell carcinoma (1 pt) of the UB (n=13) or ureter (n=4) were treated with SR and IOERT. Pts had LRR after radical cystoprostatectomy or nephroureterectomy (n=15) or advanced primary tumor (n=2). Extent of SR was R0 (microscopic negative margins), R1 (microscopic positive margins), and R2 (gross residual tumor) in 7, 1, and 9 pts, respectively. After maximal SR, IOERT was delivered to the tumor bed. Median IOERT dose and energy delivered were 12.5 Gy (range; 10-20) and 9 MeV (range; 6-18), respectively, with 1 (n=15), 2 (n=1), or 3 (n=1) IOERT fields. Sixteen pts also received perioperative external beam radiotherapy (EBRT) with a median dose of 50.4 Gy (range; 21.6- 60). Five pts received concurrent chemotherapy (CT) with perioperative EBRT. Overall (OS), disease-free survival (DFS) and relapse patterns were estimated from the date of SR and IOERT using the Kaplan-Meier method.

Results: The median pt age was 63 years (yrs) (range; 51-76). The median follow-up of surviving pts was 3.6 yrs (range; 1.1-10.0). OS and DFS at 1, 2, and 5 yrs were 53%, 31%, and 16%, and 24%, 18%, and 18%, respectively. Central (within the IOERT field), locoregional (tumor bed or first echelon draining lymphatics), and distant relapse at 2 yrs were 15%, 49%, and 67%, respectively. Seven pts received systemic CT after relapse. Mortality within 30 days of SR and IOERT was 0%. Two pts (12%) experienced grade 4-5 (NCI-CTCAE v. 4) toxicity potentially related to the multimodality therapy.

Conclusions: For pts with LRR or advanced primary tumor of the UB or ureter, this multimodality therapy including SR and IOERT resulted in durable OS and DFS in a small but significant number of pts. Both LRR and distant relapse were common, indicating a need for more effective systemic therapy along with more refined locoregional therapy.

No significant financial relationships to disclose.

Quality of life after pelvic radiotherapy with hypofractionated IMRT boost and long-term hormone therapy for locally advanced prostate cancer

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Background: Combined radiotherapy (RT) and long-term hormonal therapy (HT) is a standard treatment option for high-risk prostate cancer. Dose escalated RT alone has been shown to improve disease free survival. Increased sensitivity of prostate cancer to high doses per fraction has led to hypofractionation as a method to radiobiologically escalate dose.We report on the quality of life of patients treated with combined hypofractionated RT and HT.

Methods: A prospective phase I/II study enrolling patients with any of: clinical T3, PSA ≥20, or Gleason 8-10. Forty-five Gy (1.8 Gy/fraction) was delivered to the pelvic nodes with a concomitant 22.5 Gy intensity-modulated RT boost to the prostate, for a total of 67.5 Gy (2.7 Gy/fraction) in 25 fractions over 5 weeks. Hormonal therapy was administered for 2-3 years. Patient reported outcomes were measured at baseline and every 6 months using the validated Expanded Prostate Cancer Index Composite (EPIC) questionnaire, which measures urinary, bowel, sexual, and hormonal domains.

Results: Sixty patients with a minimum 24 months of patient-reported outcomes were analyzed. Mean scores comparing baseline to 24 month values are reported. There were no statistically significant changes in the urinary summary scores (86.3 vs. 86.0, p=0.45) or any of the urinary subscales (function, bother, incontinence, irritative/obstructive). Domain summary score decreases were observed in: bowel by 4.4% (94.7 vs. 90.3, p<0.01), sexual by 27% (44.5 vs. 17.5, p<0.01), and hormonal by 11.9% (93.1 vs. 81.2, p<0.01). Examining time trends in outcomes, most changes occurred within the first 6 months with smaller changes thereafter.

Conclusions: Hypofractionated RT combined with long-term HT is associated with good patient-reported urinary and bowel outcomes at 24 months. Sexual and hormonal summary scores are affected, largely due to continued androgen deprivation therapy. Further follow-up is needed to document patient reported outcomes after testosterone recovery.

No significant financial relationships to disclose.

High-sensitivity C-reactive protein concentrations among patients with and without diabetes in a multiethnic population of Singapore: CREDENCE Study

OBJECTIVES

To determine whether high-sensitivity C-reactive protein (hs-CRP) concentrations differ between Chinese, Malays, and Indians with and without type 2 diabetes mellitus and to look for an association with demographic, metabolic and therapeutic variables.

METHODS

Phase 1: We retrieved records of 50 Chinese, 51 Malay, and 67 Indian individuals who had routine health screening blood tests. Phase 2: We recruited 111 Chinese, 68 Malays, and 67 Indians with type 2 diabetes mellitus and measured their hs-CRP in addition to standard laboratory tests.

RESULTS

Phase 1: The median hs-CRP was 0.6 mg/L (0.2-6.2) in Chinese, 1.2 mg/L (0.2-7.9) in Malays, and 1.9 mg/L (0.2-10.0) in Indians. The Indians had higher hs-CRP compared to Chinese (P < 0.05) when adjusted for age, sex, body mass index (BMI), lipids, blood pressure, and smoking, and a significant correlation was seen between female sex, smoking status, fasting glucose and triglyceride concentration, and hs-CRP in all three ethnicities. Phase 2: The median hs-CRP was 1.2 mg/L (0.2-9.9) in Chinese, 2.2 mg/L (0.2-9.0) in Malays, and 2.3 mg/L (0.2-9.8) in Indians. Indians had higher hs-CRP when compared to Chinese (P < 0.05) and a significant correlation was seen between BMI, female gender, diabetes, and the use of metformin and hs-CRP in all three ethnicities (P < 0.05) when adjusted for the above variables and use of aspirin, angiotensin-converting enzyme inhibitor/angiotensin receptor blockers (ACE-I/ARB), statin, metformin, rosiglitazone, sulfonylurea, glinides, acarbose, and insulin.

CONCLUSION

hs-CRP concentrations are significantly higher in Indians compared to the Chinese (in both the diabetic and nondiabetic individuals) after adjustment for the various demographic, metabolic, and therapeutic variables.

Maternal buprenorphine dose, placenta buprenorphine, and metabolite concentrations and neonatal outcomes

Buprenorphine is approved as pharmacotherapy for opioid dependence in nonpregnant patients in multiple countries and is currently under investigation for pregnant women in the United States and Europe. This research evaluates the disposition of buprenorphine, opiates, cocaine, and metabolites in five term placentas from a US cohort. Placenta and matched meconium concentrations were compared, and relationships among maternal buprenorphine dose, placenta concentrations, and neonatal outcomes after controlled administration during gestation were investigated. Buprenorphine and/or metabolites were detected in all placenta specimens and were uniformly distributed across this tissue (coefficient of variation less than 27.5%, four locations), except for buprenorphine in three placentas. In two of these, buprenorphine was not detected in some locations and in the third placenta was totally absent. Median (range) concentrations were 1.6 ng/g buprenorphine (not detected to 3.2), 14.9 ng/g norbuprenorphine (6.2-24.2), 3 ng/g buprenorphine-glucuronide (1.3-5.0), and 14.7 ng/g norbuprenorphine-glucuronide (11.4-25.8). Placenta is a potential alternative matrix for detecting in utero buprenorphine exposure, but at lower concentrations (15- to 70-fold) than in meconium. Statistically significant correlations were observed for mean maternal daily dose from enrollment to delivery and placenta buprenorphine-glucuronide concentration and for norbuprenorphine-glucuronide concentrations and time to neonatal abstinence syndrome onset and duration, for norbuprenorphine/norbuprenorphine-glucuronide ratio and maximum neonatal abstinence syndrome score, and newborn length. Analysis of buprenorphine and metabolites in this alternative matrix, an abundant waste product available at the time of delivery, may be valuable for prediction of neonatal outcomes for clinicians treating newborns of buprenorphine-exposed women.

Methadone maintenance and long-term lactation

Breastfeeding among methadone-maintained women is frequently challenged because of unclear guidelines regarding this practice. Previous research has confirmed that concentrations of methadone in breastmilk in the neonatal period are low. Currently unknown are the concentrations of methadone in breastmilk among women who breastfeed for longer periods of time. The purpose of this research is to examine concentrations of methadone in the plasma and breastmilk of women who breastfeed their infants beyond the neonatal period. Four methadone-maintained women provided blood and breastmilk samples up to 6 months postpartum. The concentrations of methadone in blood and breastmilk were low, contributing to the recommendation of breastfeeding for some methadone-maintained women.

Methadone maintenance and breastfeeding in the neonatal period

OBJECTIVE

In a sample of methadone-maintained breastfeeding women and a matched group of formula-feeding women, this study evaluated concentrations of methadone in breast milk among breastfeeding women and concentrations of methadone in maternal and infant plasma in both groups.

METHODS

Eight methadone-maintained (dose: 50-105 mg/day), lactating women provided blood and breast milk specimens on days 1, 2, 3, 4, 14, and 30 after delivery, at the times of trough and peak maternal methadone levels. Paired specimens of foremilk and hindmilk were obtained at each sampling time. Eight matched formula-feeding subjects provided blood samples on the same days. Infant blood samples for both groups were obtained on day 14. Urine toxicological screening between 36 weeks of gestation and 30 days after the birth confirmed that subjects were not using illicit substances in the perinatal period.

RESULTS

Concentrations of methadone in breast milk were low (range: 21.0-462.0 ng/mL) and not related to maternal dose. There was a significant increase in methadone concentrations in breast milk over time for all 4 sampling times. Concentrations of methadone in maternal plasma were not different between groups and were unrelated to maternal dose. Concentrations of methadone in infant plasma were low (range: 2.2-8.1 ng/mL) in all samples. Infants in both groups underwent neurobehavioral assessments on days 3, 14, and 30; there were no significant effects of breastfeeding on neurobehavioral outcomes. Fewer infants in the breastfed group required pharmacotherapy for neonatal abstinence syndrome, but this was not a statistically significant finding.

CONCLUSION

Results contribute to the recommendation of breastfeeding for methadone-maintained women.

How much does Gleason grade of follow-up biopsy differ from that of initial biopsy in untreated, Gleason score 4-7, clinically localized prostate cancer?

OBJECTIVE

To compare histologic grades between an initial biopsy and a follow-up biopsy in untreated, Gleason score (GS) 4-7, clinically localized prostate cancer.

METHODS AND MATERIALS

In a prospective single-arm cohort study, clinically localized, GS 4-7, prostate cancer was managed with active surveillance alone, provided that a pre-defined definition of disease progression was not met. One hundred five (63%) of a total of 168 eligible patients underwent a follow-up prostate biopsy during surveillance. Median time to a follow-up biopsy was 22 months (range: 7-81). Histologic grades between these two biopsies were compared to evaluate the extent of histologic grade change.

RESULTS

On the follow-up biopsy, GS was unchanged in 33 patients (31%), upgraded in 37 (35%), and downgraded in 34 (32%). Eleven (10%) had upgrading by 2 Gleason points or more. Eight (8%) had upgrading to GS 8 (none to GS 9 or 10); of these, six were among those with upgrading by 2 Gleason points or more. Twenty-seven (26%) had no malignancy on the follow-up biopsy. Negative follow-up biopsy was more prevalent in patients with a small volume of malignancy in the initial biopsy and a low baseline PSA.

CONCLUSIONS

No consistent change in histologic grade was observed on the follow-up biopsy at a median of 22 months in untreated, GS 4-7, clinically localized prostate cancer. Upgrading to GS > or =8 or by 2 Gleason points or more was relatively uncommon.

Testosterone recovery after two years of androgen suppression in prostate cancer patients

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Background: The time course of testosterone (TST) recovery after prolonged androgen suppression (AS) is not well established. We examined TST recovery prospectively in prostate cancer (PCa) patients treated with 2 years of AS. Methods: 153 PCa men with pT3N0 or positive margins after radical prostatectomy (RP), or with PSA relapse (persistently detectable postoperative PSA [= 0.2 ng/mL], delayed detectable PSA = 6 months after surgery, or palpable/biopsy proven local recurrence after RP), were treated with radiation (RT) to the prostate bed (60 - 70 Gy in 30 - 35 fractions) plus 2 years of AS as part of a phase II study. AS consisted of nilutamide 100 mg PO tid for 4 weeks, starting within 1 week after completing RT, and busereline acetate 6.6 mg SC every 2 months for 2 years, starting within 2 weeks of nilutamide. The primary endpoint was PSA relapse-free survival. Serum TST levels were measured at baseline, every 4 months during AS, and every 6 months after completing AS. The planned sample size was 150 patients. Time to TST recovery was analyzed using the Kaplan-Meier method. Cox Proportional Hazards regression was used for a multivariate analysis of predictive factors for TST recovery. Results: 122 men completed the planned AS. Median follow up after finishing AS was 36.4 months (range 9.4 - 76.2). A castrate TST level was defined as =1.7 nmol/L (50 ng/dL), with normal levels being 10 - 40 nmol/L. All men achieved castrate TST levels on AS. Table 1 shows TST recovery at 36 months after completing AS and median times to recovery. Median recovery time to normal TST was 27 months, although 8% of men did not recover to above castrate levels by 3 years. On multivariate analysis, younger age (<60 vs. =60) predicted for a significantly shorter recovery time to normal TST (P = <0.0001), while baseline TST (<10 nmol/L vs. =10.0 nmol/L) was of borderline significance (P = 0.06). Conclusions: TST recovery after 2 years of AS is protracted. Older men have significantly longer recovery times.

[Table: see text]

[Table: see text]

Preliminary results of a phase II study of continuous low dose metronomic (LDM) cyclophosphamide (CTX) and celecoxib (CEL) for asymptomatic hormone refractory prostate cancer (HRPC) with assessment of anti-angiogenic biomarkers

14046

Background: LDM CTX is a minimally toxic anti-angiogenic therapy that has demonstrated activity in multiple tumour types including HRPC. Increased Cyclooxygenase 2 (COX 2, a prostaglandin synthase enzyme) expression appears to be a consistent feature of a variety of human tumours, including prostate cancer. COX 2 inhibitors like CEL exhibit anti-tumour activity in pre-clinical studies, at least in part due to their anti-angiogenic activity. Pre-clinical work supports the concept that the combination of selective angiogenesis inhibitors like CEL with metronomic chemotherapy can enhance the effects of these agents on tumour angiogenesis. Methods: Men with asymptomatic HRPC at a single Canadian centre received celecoxib 400 mg po BID and cyclophosphamide 50 mg po daily. The primary efficacy endpoint of this 2 stage phase II study is disease control rate (DCR): 50% PSA response, tumour response or prolonged (=6 mos) PSA or stable measurable disease. This study is also assessing the safety of LDM CTX and CEL as well as potential anti-angiogenic biomarkers in these patients including circulating endothelial cells and their precursors (CEC/P), plasma levels of thrombospondin-1 (TSP-1) and vascular endothelial growth factor (VEGF). Results: Enrollment for the first stage of this study (10 men) has been completed. There were 2 patients with disease control by the a priori criteria: one patient with a partial tumour response (PR) (PR duration 13 mos with PSA stabilization for 12 mos) and one patient that had both prolonged stable PSA (7 mos) and prolonged stable measurable disease (8 mos). In addition, another patient had an unconfirmed PR. The therapy was well tolerated. One patient had angina that responded well to medical therapy but there were no serious arterial-thromboembolic events. One patient developed grade 3 hypertension. All other toxicities were grade 1/2. Data on CEC/P, TSP-1 and VEGF levels will be presented at the meeting. Conclusions: LDM CTX + CEL is a well tolerated therapy in men with asymptomatic HRPC. 2/10 patients achieved disease control in the first stage of the trial, meeting the criteria to proceed to the second stage.

[Table: see text]

Rise in Prostate-Specific Antigen in Men with Untreated Low-Grade Prostate Cancer Is Slower During Spring-Summer

To test the hypothesis that the rate of rise in prostate-specific antigen (PSA) is slower during the spring-summer than during the rest of the year, we used PSA data from a prospective single-arm cohort study of men who had been followed to characterize a watchful observation protocol with selective delayed intervention for clinically localized, low-to-intermediate grade prostate adenocarcinoma. The rate of PSA increase was calculated as the visit-to-visit slope of log (PSA) against time, from 1 calendar-quarter visit to the next. The nonparametric Friedman test confirmed differences in rate of PSA rise among the calendar quarters (P = 0.041). Post hoc analysis showed the rate of PSA increase during Q2 was significantly slower than in each one of the other calendar quarters (Q1 versus Q2, P = 0.025; Q3 versus Q2, P = 0.002; Q4 versus Q2, P = 0.013), with no differences among quarters Q1, Q3, and Q4. These results are consistent with the vitamin D hypothesis that the higher 25-hydroxyvitamin D levels associated with spring and summer have a desirable effect on prostate biology. The therapeutic implication is that vitamin D supplementation in the range of 2000 IU/d, a dose comparable to the effect of summer, can benefit men monitored for rising PSA.

Comparison of histologic grade between initial and follow-up biopsy in untreated, low to intermediate grade, localized prostate cancer

OBJECTIVE

To examine the change of histologic grade of untreated, low to intermediate grade, clinically localized prostate cancer over time on repeat prostate biopsy.

METHODS AND MATERIALS

In a prospective single-arm cohort study, patients were managed with observation alone unless they met pre-defined criteria of disease progression (PSA, clinical or histologic progression). Sixty-seven (54%) of a total of 123 eligible patients underwent follow-up prostate biopsy. Median time to the follow-up biopsy was 22 months (range: 7-60).

RESULTS

On the follow-up biopsy, Gleason score was unchanged in 20 patients (30%), upgraded in 19 (28%), and downgraded in 27 (40%). Twenty-one (31%) had no malignancy on the follow-up biopsy. Sixteen (37%) of 43 patients with < or = 2 positive cores on the initial biopsy had negative follow-up biopsy, while only 2 (11%) out of 18 with > or = 3 positive cores on the initial biopsy did. Five (7%) patients were upgraded to Gleason score 8. There was no correlation between the extent of grade change and baseline variables (age, clinical stage, and initial PSA) as well as PSA doubling time.

CONCLUSIONS

There was no consistent histologic upgrade on the follow-up biopsy at a median of 22 months in untreated, low to intermediate grade, clinically localized prostate cancer.

Is there a progression of histologic grade from radical prostatectomy to local recurrence in patients with clinically isolated local recurrence following surgery?

OBJECTIVE

To evaluate whether there is any histologic progression from radical prostatectomy (RP) to local recurrence in patients with clinically isolated local recurrence following RP.

METHODS AND MATERIALS

A total of 43 patients with clinically isolated, biopsy proven, local recurrence following RP were retrospectively analyzed with respect to the change in Gleason score (GS) from RP to local recurrence. Central pathology review was undertaken for both RP and local recurrence biopsy specimens. The changes in primary and secondary Gleason grade (GG), and any potential correlation between the extent of GS change and other variables were also examined.

RESULTS

Median age at the time of local recurrence was 67 years (range: 55-78). Median interval between RP and local recurrence was 3.6 years (range: 0.3-17.7). Eight had a short course (<3 months) of hormone therapy prior to RP. Initial GS of RP specimens was 5, 6, 7, 8, and 9 in 1, 3, 29, 1, and 9 patients, respectively. At the time of local recurrence, GS was upgraded in 13, unchanged in 23, and downgraded in 7. The extent of GS change was correlated with the interval between RP and local recurrence, but not with pathological T stage or age.

CONCLUSION

There was no statistically significant change in GS from RP to local recurrence, although there was a trend toward a higher GS at the time of local recurrence. The extent of GS change was associated positively with the elapsed time to local recurrence.