Intraoperative radiotherapy in early breast cancer

BACKGROUND

Intraoperative radiotherapy (IORT) constitutes a paradigm shift from the conventional 3-5 weeks of whole-breast external beam radiotherapy (EBRT). IORT enables delivery of radiation at the time of excision of the breast tumour, targeting the area at highest risk of recurrence, while minimizing excessive radiation exposure to healthy breast tissue. The rationale for IORT is based on the observation that over 90 per cent of local recurrences after breast-conserving surgery occur at or near the original operation site.

METHODS

This article reviews trials of IORT delivered with different techniques and devices.

RESULTS

IORT is a very attractive option for delivering radiotherapy, reducing the traditional fractionated treatment to a single fraction administered at the time of surgery. IORT has been shown to be associated with reduced toxicity and has several potential benefits over EBRT. Only two randomized clinical trials have been published to date. The TARGIT-A and ELIOT trials have demonstrated that IORT is associated with a low rate of local recurrence, although higher than that after EBRT (TARGIT-A: 3·3 versus 1·3 per cent respectively, P = 0·042; ELIOT: 4·4 versus 0·4 per cent, P < 0·001). However, the local recurrence rate for IORT fell within the predefined 2·5 per cent non-inferiority margin in TARGIT-A, and the 7·5 per cent equivalence margin in ELIOT.

CONCLUSION

Longer follow-up data from existing trials, optimization of patient criteria and cost-effectiveness analyses are needed. Based on the current evidence, IORT can be offered as an alternative to EBRT to selected patients within agreed protocols, and outcomes should be monitored within national registries.

Long-term efficacy and safety of canagliflozin over 104 weeks in patients aged 55-80 years with type 2 diabetes

AIMS

The long-term efficacy and safety of canagliflozin, a sodium glucose co-transporter 2 inhibitor, was evaluated over 104 weeks in patients aged 55-80 years with type 2 diabetes mellitus (T2DM) inadequately controlled on a stable antihyperglycaemic agent regimen.

METHODS

In this randomized, double-blind, phase III study, patients received canagliflozin 100 or 300 mg or placebo once daily during a 26-week core period (N = 714) and a 78-week extension period (n = 624). Efficacy endpoints at week 104 included change from baseline in glycated haemoglobin (HbA1c), fasting plasma glucose (FPG) and systolic blood pressure, and percent change from baseline in body weight and fasting plasma lipids. Safety was assessed by adverse event (AE) reports.

RESULTS

At week 104, canagliflozin 100 and 300 mg were associated with reductions in HbA1c versus placebo (-0.32 and -0.43% vs 0.17%, respectively; overall mean baseline, 7.7%) and more patients achieved HbA1c <7.0% with canagliflozin 100 and 300 mg than with placebo (35.8 and 41.9% vs 20.3%, respectively). Reductions in FPG, body weight and systolic blood pressure, and increases in high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) were seen with canagliflozin compared with placebo. The overall incidence rates of AEs over 104 weeks were 88.0, 89.8 and 86.1% with canagliflozin 100 and 300 mg and placebo, respectively; serious AE rates were low across treatment groups. The incidence rates of urinary tract infections, genital mycotic infections and osmotic diuresis- and volume depletion-related AEs were higher with canagliflozin than with placebo.

CONCLUSION

Canagliflozin improved glycaemic control, reduced body weight and systolic blood pressure, and was generally well tolerated in patients aged 55-80 years with T2DM over 104 weeks.

Survival after postoperative morbidity: a longitudinal observational cohort study

Background

Previous studies have suggested that there may be long-term harm associated with postoperative complications. Uncertainty exists however, because of the need for risk adjustment and inconsistent definitions of postoperative morbidity.

Methods

We did a longitudinal observational cohort study of patients undergoing major surgery. Case-mix adjustment was applied and morbidity was recorded using a validated outcome measure. Cox proportional hazards modelling using time-dependent covariates was used to measure the independent relationship between prolonged postoperative morbidity and longer term survival.

Results

Data were analysed for 1362 patients. The median length of stay was 9 days and the median follow-up time was 6.5 yr. Independent of perioperative risk, postoperative neurological morbidity (prevalence 2.9%) was associated with a relative hazard for long-term mortality of 2.00 [P=0.001; 95% confidence interval (CI) 1.32–3.04]. Prolonged postoperative morbidity (prevalence 15.6%) conferred a relative hazard for death in the first 12 months after surgery of 3.51 (P<0.001; 95% CI 2.28–5.42) and for the next 2 yr of 2.44 (P<0.001; 95% CI 1.62–3.65), returning to baseline thereafter.

Conclusions

Prolonged morbidity after surgery is associated with a risk of premature death for a longer duration than perhaps is commonly thought; however, this risk falls with time. We suggest that prolonged postoperative morbidity measured in this way may be a valid indicator of the quality of surgical healthcare. Our findings reinforce the importance of research and quality improvement initiatives aimed at reducing the duration and severity of postoperative complications.

Tumour-infiltrating lymphocytes predict for outcome in HPV-positive oropharyngeal cancer

BACKGROUND

Human papillomavirus (HPV)-positive oropharyngeal cancer (OPSCC) is associated with improved survival compared with HPV-negative disease. However, a minority of HPV-positive patients have poor prognosis. Currently, there is no generally accepted strategy for identifying these patients.

METHODS

We retrospectively analysed 270 consecutively treated OPSCC patients from three centres for effects of clinical, pathological, immunological, and molecular features on disease mortality. We used Cox regression to examine associations between factors and OPSCC death, and developed a prognostic model for 3-year mortality using logistic regression analysis.

RESULTS

Patients with HPV-positive tumours showed improved survival (hazard ratio (HR), 0.33 (0.21-0.53)). High levels of tumour-infiltrating lymphocytes (TILs) stratified HPV-positive patients into high-risk and low-risk groups (3-year survival; HPV-positive/TIL(high)=96%, HPV-positive/TIL(low)=59%). Survival of HPV-positive/TIL(low) patients did not differ from HPV-negative patients (HR, 1.01; P=0.98). We developed a prognostic model for HPV-positive tumours using a 'training' cohort from one centre; the combination of TIL levels, heavy smoking, and T-stage were significant (AUROC=0·87). This model was validated on patients from the other centres (detection rate 67%; false-positive rate 5.6%; AUROC=0·82).

INTERPRETATION

Our data suggest that an immune response, reflected by TIL levels in the primary tumour, has an important role in the improved survival seen in most HPV-positive patients, and is relevant for the clinical evaluation of HPV-positive OPSCC.

Antimicrobial resistant Escherichia coli in the municipal wastewater system: effect of hospital effluent and environmental fate

The prevalence of antimicrobial resistant (AMR) bacteria is increasing worldwide and remains a significant medical challenge which may lead to antimicrobial redundancy. The contribution of hospital effluent to the prevalence of resistance in wastewater treatment plant (WWTP) effluents is not fully understood. AMR bacteria contained in hospital effluent may be released into the aquatic and soil environments after WWTP processing. Hence, the objective of this study is to identify the extent hospital effluent contributes to contamination of these environments by comparing two WWTPs, one which receives hospital effluent and one which does not. AMR Escherichia coli were monitored in the two WWTPs. A model was developed using these monitored values to predict the effect of hospital effluent within a WWTP. The model predicted levels of AMR E. coli in the aquatic environment and potential bather exposure to AMR E. coli. The model results were highly variable. WWTP influent containing hospital effluent had a higher mean percentage of AMR E. coli; although, there appeared to be no within treatment plant effect on the prevalence of AMR E. coli. Examination of WWTP sludge showed a similar variation. There appeared to be no consistent effect from the presence of hospital effluent. The human exposure assessment model predicted swimmer intake of AMR E. coli between 6 and 193CFU/100ml sea water. It appears that hospital effluent is not the main contributing factor behind the development and persistence of AMR E. coli within WWTPs, although resistance may be too well-developed to identify an influence from hospital effluent. Mitigation needs to focus on the removal of already present resistant bacteria but for new or hospital specific antimicrobials focus needs to be on their limited release within effluents or separate treatment.

Long-term fracture rates seen with continued ibandronate treatment: pooled analysis of DIVA and MOBILE long-term extension studies

Ibandronate reduces the risk of vertebral and non-vertebral fractures versus placebo in postmenopausal women with osteoporosis. This analysis, in which fractures were reported as safety events, showed that long-term use of ibandronate was associated with low fracture rates over 5 years of treatment.

INTRODUCTION

A previous post-hoc meta-analysis of 2-3 year studies found that ibandronate regimens with annual cumulative exposure (ACE) of ≥10.8 mg reduced the risk of vertebral and nonvertebral fractures (NVFs) versus placebo in postmenopausal women. This post-hoc analysis used individual patient data from the 2-year monthly oral ibandronate in ladies (MOBILE) and dosing intravenous administration (DIVA) studies, including the 3-year long-term extensions (LTEs), to assess fracture risk in patients treated with ibandronate for 5 years.

METHODS

Patients treated for 2 years in MOBILE with monthly oral ibandronate 150 mg (n = 176) and in DIVA with IV ibandronate every 2 months 2 mg (n = 253) or quarterly 3 mg (n = 263) who continued on the same regimens for 3 additional years in the LTEs were included. Three-year placebo data (n = 1,924) were obtained from the ibandronate osteoporosis vertebral fracture trial in North America and Europe (BONE) and IV Fracture Prevention trials. The primary endpoint was clinical fracture rate; clinical fracture data were collected as adverse events. Time to fracture was analyzed using Kaplan-Meier and statistical analysis was conducted using the log-rank test. All clinical fractures included all NVFs and symptomatic vertebral fractures.

RESULTS

For ibandronate regimens with ACE ≥10.8 mg, time to fracture was significantly longer for all clinical fractures, NVFs, and clinical vertebral fractures versus placebo (P = 0.005). For all fracture types, the rate of fracture appeared stable during the 5-year treatment period.

CONCLUSION

In women with postmenopausal osteoporosis, continuous treatment with ibandronate over 5 years results in low sustained clinical fracture rate.

Cortical regulation of dopaminergic neurons: role of the midbrain superior colliculus

Dopaminergic (DA) neurons respond to stimuli in a wide range of modalities, although the origin of the afferent sensory signals has only recently begun to emerge. In the case of vision, an important source of short-latency sensory information seems to be the midbrain superior colliculus (SC). However, longer-latency responses have been identified that are less compatible with the primitive perceptual capacities of the colliculus. Rather, they seem more in keeping with the processing capabilities of the cortex. Given that there are robust projections from the cortex to the SC, we examined whether cortical information could reach DA neurons via a relay in the colliculus. The somatosensory barrel cortex was stimulated electrically in the anesthetized rat with either single pulses or pulse trains. Although single pulses produced small phasic activations in the colliculus, they did not elicit responses in the majority of DA neurons. However, after disinhibitory intracollicular injections of the GABA_A antagonist bicuculline, collicular responses were substantially enhanced and previously unresponsive DA neurons now exhibited phasic excitations or inhibitions. Pulse trains applied to the cortex led to phasic changes (excitations to inhibitions) in the activity of DA neurons at baseline. These were blocked or attenuated by intracollicular administration of the GABA_A agonist muscimol. Taken together, the results indicate that the cortex can communicate with DA neurons via a relay in the SC. As a consequence, DA neuronal activity reflecting the unexpected occurrence of salient events and that signaling more complex stimulus properties may have a common origin.

Insulin degludec: overview of a novel ultra long-acting basal insulin

All the basal insulin products currently available have suboptimal pharmacokinetic (PK) properties, with none reliably providing a reproducible and peakless pharmacodynamic (PD) effect that endures over 24 h from once-daily dosing. Insulin degludec is a novel acylated basal insulin with a unique mechanism of protracted absorption involving the formation of a depot of soluble multihexamer chains after subcutaneous injection. PK/PD studies show that insulin degludec has a very long duration of action, with a half-life exceeding 25 h. Once-daily dosing produces a steady-state profile characterized by a near-constant effect, which varies little from injection to injection in a given patient. Clinically, insulin degludec has been shown consistently to carry a lower risk of nocturnal hypoglycaemia than once-daily insulin glargine, in both basal+bolus and basal-only insulin regimens. The constancy of the steady-state profile of insulin degludec also means that day-to-day irregularities at the time of injection have relatively little PD influence, thereby offering the possibility of greater treatment flexibility for patients.

The effect of hospital effluent on antimicrobial resistant E. coli within a municipal wastewater system

There is a concern that hospital effluent potentially containing antimicrobial compounds, antimicrobial resistant (AMR) bacteria and genetic determinants of resistance may contribute to the emergence, dissemination and persistence of AMR bacteria in municipal wastewaters. Hence, it is of interest to investigate the effect, if any, hospital effluent has on the percentage of AMR bacteria within wastewater. Water from two wastewater treatment plants (WWTPs) (one receives and treats hospital effluent (WWTPhe) and the second does not (WWTPc)) were examined for E. coli expressing resistance to seven antimicrobials (ampicillin, streptomycin, cefoxitin, cefotaxime, tetracycline, sulphonamide and ciprofloxacin). A two-sample t-test showed that AMR E. coli are present in WWTP influent and effluent, irrespective of receiving hospital effluent, and are being released into the environment (no statistical difference in count between the two WWTPs). The effect of hospital effluent on resistance varies for each AMR bacteria. Excluding tetracycline, sulphonamide and ciprofloxacin, the results suggest that the release of hospital effluent does not significantly affect the frequency with which AMR E. coli are detected in effluent. For some hospital specific antimicrobial agents, such as ciprofloxacin, the release of hospital effluent is associated with an increased proportion of antimicrobial resistance. The results suggest resistance to AMR E. coli may already be well developed in the community, making the effect of hospital effluent on AMR E. coli indistinguishable. However, for hospital specific antimicrobials, there may be a selective effect and hence limiting the release of hospital effluent containing such antimicrobials may impact the proportion of antimicrobial resistance. This research has provided statistical evidence to support necessary mitigation and remediation of antimicrobial residue release and subsequent resistance in the environment.

Simulation model to predict the fate of ciprofloxacin in the environment after wastewater treatment

The extent hospital effluent contributes to antimicrobial presence in the environment and its impact on resistance dissemination remains unknown. To investigate the fate of the antimicrobial ciprofloxacin in hospital effluent a Monte Carlo simulation model was developed to model levels from hospital use to wastewater treatment plant (WWTP) effluent release, in addition to modeling resistance formation potential, hazard quotient (HQ) and swimmer exposure. The mean predicted concentration (PC) of ciprofloxacin in hospital effluent, urban effluent, WWTP effluent, sludge, soil and sea water was 579, 6.06, 2.59, 3.48, 0.006 and 0.15 mg/m(3), respectively. A parallel surveillance study confirmed levels of ciprofloxacin above or below the limit of detection. The model predicted levels would never exceed the ECOSAR toxicity value. The model predicted a 98% probability of ciprofloxacin exhibiting a HQ > 1 (low toxicity concern). The mean ciprofloxacin PC in WWTP effluent was less than the minimum inhibitory concentration (MIC). The probability of conditions in WWTP effluent being favorable for resistance at 20% and 80% of the MIC was 3% and 72%, respectively. In all instances, when the MIC was bound, the probability for resistance formation within soil and sea water was < 1%. The probability of a swimmer being exposed to a level of ciprofloxacin greater than the acceptable daily intake was negligible. The study concluded that release of hospital effluent into the environment may lead to concentrations of ciprofloxacin which are of low toxicity concern but may be conducive to resistance formation and allow for the dissemination of resistance.

The effect of conventional wastewater treatment on the levels of antimicrobial-resistant bacteria in effluent: a meta-analysis of current studies

Antimicrobial agents in the environment are a cause for concern. Antimicrobial drug residues and their metabolites reach the aquatic and terrestrial environment primarily through wastewater treatment plants (WWTP). In addition to the potential direct negative health and environmental effects, there is potential for the development of antimicrobial-resistant bacteria. Residue levels below the minimum inhibitory concentration for a bacterial species can be important in selection of resistance. There is uncertainty associated with resistance formation during WWTP processing. A meta-analysis study was carried out to analyse the effect of WWTP processing on the levels of antimicrobial-resistant bacteria within bacterial populations. An analysis of publications relating to multiple antimicrobial-resistant (MAR) bacteria (n = 61), single antimicrobial-resistant (SAR) E. coli (n = 81) and quinolone/fluoroquinolone-resistant (FR) bacteria (n = 19) was carried out. The odds-ratio (OR) of MAR (OR = 1.60, p < 0.01), SAR (OR = 1.33, p < 0.01) and FR (OR = 1.19, p < 0.01) bacteria was determined. The results infer that WWTP processing results in an increase in the proportion of resistant bacteria in effluent, even though the overall bacterial population may have reduced (i.e. a reduction in total bacterial numbers but an increase in the percentage of resistant bacteria). The results support the need for further research into the development of antimicrobial-resistant strains and possible selective pressures operating in WWTPs.

Barium proctography vs magnetic resonance proctography for pelvic floor disorders: a comparative study

AIM

Accurate and reliable imaging of pelvic floor dynamics is important for tailoring treatment in pelvic floor disorders; however, two imaging modalities are available. Barium proctography (BaP) is widely used, but involves a significant radiation dose. Magnetic resonance (MR) proctography allows visualization of all pelvic midline structures but patients are supine. This project investigates whether there are measurable differences between BaP and MR proctography. Patient preference for the tests was also investigated.

METHODS

Consecutive patients referred for BaP were invited to participate (National Research Ethics Service approved). Participants underwent BaP in Poole and MR proctography in Dorchester. Proctograms were reported by a consultant radiologist with pelvic floor subspecialization.

RESULTS

A total of 71 patients were recruited. Both tests were carried out on 42 patients. Complete rectal emptying was observed in 29% (12/42) on BaP and in 2% (1/42) on MR proctography. Anismus was reported in 29% (12/42) on BaP and 43% (18/42) on MR proctography. MR proctography missed 31% (11/35) of rectal intussusception detected on BaP. In 10 of these cases no rectal evacuation was achieved during MR proctography. The measure of agreement between grade of rectal intussusception was fair (κ=0.260) although MR proctography tended to underestimate the grade. Rectoceles were extremely common but clinically relevant differences in size were evident. Patients reported that they found MR proctography less embarrassing but harder to empty their bowel.

CONCLUSIONS

The results demonstrate that MR proctography under-reports pelvic floor abnormalities especially where there has been poor rectal evacuation.