Treatment of the axilla in early breast cancer: past, present and future

Background: The optimal treatment of the axilla in early breast cancer is controversial. The present study reviews the pattern and predictors of regional recurrence (RR) and prognosis after RR in patients with early breast cancer treated by conservative surgery and radiotherapy (CS + RT). Implications of the results on current practice and future directions are explored. Methods: Between 1979 and 1994, 1158 patients with stage I or II breast cancer were treated with CS + RT at Westmead Hospital. Two groups of patients were compared: 782 patients who underwent axillary dissection (axillary surgery group) and 229 patients who received radiotherapy (axillary RT group) as the only axillary treatment. At least 10 lymph nodes were dissected in 82% of the axillary surgery group. Of the women in the RT group, 90% received RT to the axilla and supraclavicular fossa (SCF) only and 10% also received RT to the internal mammary chain (IMC). Results: With a median follow‐up period of 79 months for the axillary surgery group and 111 months for the axillary RT group, 27 patients developed a RR (2.8% and 2.2%, respectively). Seven patients (0.9%) in the axillary surgery group and three patients (1.3%) in the axillary RT group developed a RR in the axilla (P, not significant). Of the patients with SCF recurrences, 14 (1.8%) were in the axillary surgery group and one (0.4%) in the axillary RT group (P, not significant). One patient in the axillary surgery group developed concurrent axillary and SCF recurrences, while a patient in the axillary RT group developed an IMC recurrence. Twenty (74%) of the 27 patients with a RR developed a concurrent or subsequent distant relapse (30% and 44%, respectively). In the pathologically node‐positive patients, the axillary recurrence rate was higher in those who had less than five nodes removed (17%) than those who had 10 or more nodes removed (0%; P = 0.01). The SCF recurrence rate was higher in patients with four or more positive axillary nodes (9.5%) than in those with 0–3 positive nodes (1.5%; P = 0.003). Conclusion: Adequate treatment of the axilla by surgery or RT alone is associated with a low rate of RR. The incidence of distant relapse was substantial in patients who developed a RR, which gives emphasis to the importance of optimizing local–regional control.     

Burkholderia pseudomallei sequencing identifies genomic clades with distinct recombination,accessory, and epigenetic profiles

Burkholderia pseudomallei (Bp) is the causative agent of the infectious disease melioidosis. To investigate population diversity, recombination, and horizontal gene transfer in closely related Bp isolates, we performed whole-genome sequencing (WGS) on 106 clinical, animal, and environmental strains from a restricted Asian locale. Whole-genome phylogenies resolved multiple genomic clades of Bp, largely congruent with multilocus sequence typing (MLST). We discovered widespread recombination in the Bp core genome, involving hundreds of regions associated with multiple haplotypes. Highly recombinant regions exhibited functional enrichments that may contribute to virulence. We observed clade-specific patterns of recombination and accessory gene exchange, and provide evidence that this is likely due to ongoing recombination between clade members. Reciprocally, interclade exchanges were rarely observed, suggesting mechanisms restricting gene flow between clades. Interrogation of accessory elements revealed that each clade harbored a distinct complement of restriction-modification (RM) systems, predicted to cause clade-specific patterns of DNA methylation. Using methylome sequencing, we confirmed that representative strains from separate clades indeed exhibit distinct methylation profiles. Finally, using an E. coli system, we demonstrate that Bp RM systems can inhibit uptake of non-self DNA. Our data suggest that RM systems borne on mobile elements, besides preventing foreign DNA invasion, may also contribute to limiting exchanges of genetic material between individuals of the same species. Genomic clades may thus represent functional units of genetic isolation in Bp, modulating intraspecies genetic diversity.Burkholderia pseudomallei (Bp) is the causative agent of melioidosis, a serious infectious disease of humans and animals and a leading cause of community-acquired sepsis and pneumonia in endemic regions (Currie et al. 2010). Initially thought to be confined to Southeast Asia and Northern Australia, the prevalence of Bp appears to be spreading (Wiersinga et al. 2012), and Bp has been designated a biothreat select agent in the United States. Bp can persist in extreme environmental conditions and can infect several plant and animal hosts, including birds, dolphins, and humans (Wuthiekanun et al. 1995; Howard and Inglis 2003; Sprague and Neubauer 2004; Larsen et al. 2013). Treatment of clinical melioidosis is challenging because the bacterium is inherently resistant to many antibiotics, and Bp infections can persist in humans for more than a decade (Hayden et al. 2012; Wiersinga et al. 2012).The Bp genome comprises one of the largest and most complex bacterial genomes sequenced to date. Consisting of two large circular replicons (chromosomes) with a combined 7.2-Mb genome size (Holden et al. 2004), it contains a rich arsenal of genes related to virulence (e.g., Type III and Type VI secretion systems, polysaccharide biosynthesis clusters), metabolic pathways, and environmental adaptation (Wiersinga et al. 2012). Besides conserved regions, accessory genes on mobile elements and genomic islands may also contribute to phenotypic and clinical differences in microbial behavior (Currie et al. 2000; Sim et al. 2008). Analysis of the Bp genome has revealed previously unknown toxins and mechanisms of antibiotic resistance (Chantratita et al. 2011; Cruz-Migoni et al. 2011).Most large-scale studies of Bp genetic diversity to date have analyzed strains using multilocus sequence typing (MLST). These studies have suggested a high degree of genetic variability between Bp strains and related Burkholderia species (Cheng et al. 2008), and have shown that Bp strains belonging to different sequence types (STs) can often coexist in the same locale and sometimes even within the same sample (Pitt et al. 2007; Wuthiekanun et al. 2009). However, due to the limited number of genes analyzed by MLST, these studies cannot comment on the global proportion of genetic material shared between strains of different STs nor on the relative contribution of recombination, mutation, and horizontal gene transfer on intraspecies genetic diversity. Moreover, although previous studies have applied whole-genome sequencing (WGS) to study global patterns of Bp genetic heterogeneity and evolution, earlier Bp WGS reports have been confined to a limited number of isolates (10–12) derived from diverse geographical regions (Nandi et al. 2010), where geophysical barriers likely limit the propensity of the analyzed strains to exchange genetic material. To achieve a comprehensive understanding of genetic variation among closely related Bp strains, WGS analysis of much larger strain panels, ideally performed on strains isolated from a common region and belonging to the same (or closely related) ST groups, is required.In this study, we attempted to fill this important knowledge gap by performing WGS on 106 Bp strains drawn from a restricted Asian locale (Singapore and Malaysia). The WGS data, exceeding previous Bp WGS studies by 10-fold, enabled us to identify specific genomic clades of Bp, molecular features of Bp recombination at the whole-genome level, and accessory genome features contributing to recombination and horizontal gene transfer. We found a consistent pattern of genetic separation correlating with MLST, recombination haplotypes, shared accessory genes, and restriction modification (RM) systems. We provide evidence that restriction modification, beyond its role as defense against foreign DNA invasion, may have also partitioned the Bp species by restricting gene flow, resulting in the other observed correlations. Because RM systems are widely dispersed through the bacterial kingdom, it is possible that similar principles may apply to other bacterial species, implicating a potential role for epigenetic barriers as a driver of early incipient speciation.     

New experimental melting properties as access for predicting amino-acid solubility

The properties of melting are required for the prediction of solubility of solid compounds. Unfortunately, direct determination of the enthalpy of fusion and melting temperature by using conventional DSC or adiabatic calorimetry is often not possible for biological compounds due to decomposition during the measurement. To overcome this, fast scanning calorimetry (FSC) with scanning rates up to 2 × 10⁴ K s⁻¹ was used in this work to measure the melting parameters for l-alanine and glycine. The enthalpy of fusion and melting temperature (extrapolated to zero heating rate) were Δ_fusH = (22 ± 5) kJ mol⁻¹ and T_fus = (608 ± 9) K for l-alanine, and Δ_fusH = (21 ± 4) kJ mol⁻¹ and T_fus = (569 ± 7) K for glycine. These melting properties were used in the modeling framework PC-SAFT to predict amino-acid solubility in water. The pure-component PC-SAFT parameters and one binary parameter were taken from literature, in which these parameters were fitted to solubility-independent thermodynamic properties such as osmotic coefficients or mixture densities. It was shown that this allowed accurately predicting amino-acid solubility in water over a broad temperature range. The combined methodology of PC-SAFT and FSC proposed in this work opens the door for predicting solubility of molecules that decompose before melting.

New experimental melting properties combined with PC-SAFT allow quantitative solubility predictions of amino acids in water.     

The development of silk fibroin scaffolds using an indirect rapid prototyping approach: Morphological analysis and cell growth monitoring by spectral-domain optical coherence tomography

To date, naturally derived biomaterials are rarely used in advanced tissue engineering (TE) methods despite their superior biocompatibility. This is because these native materials, which consist mainly of proteins and polysaccharides, do not possess the ability to withstand harsh processing conditions. Unlike synthetic polymers, natural materials degrade and decompose rapidly in the presence of chemical solvents and high temperature, respectively. Thus, the fabrication of tissue scaffolds using natural biomaterials is often carried out using conventional techniques, where the efficiency in mass transport of nutrients and removal of waste products within the construct is compromised. The present study identified silk fibroin (SF) protein as a suitable material for the application of rapid prototyping (RP) or additive manufacturing (AM) technology. Using the indirect RP method, via the use of a mould, SF tissue scaffolds with both macro- and micro-morphological features can be produced and qualitatively examined by spectral-domain optical coherence tomography (SD-OCT). The advanced imaging technique showed the ability to differentiate the cells and SF material by producing high contrasting images, therefore suggesting the method as a feasible alternative to the histological analysis of cell growth within tissue scaffolds.     

Ministry of Health Clinical Practice Guidelines: Anxiety Disorders

The Ministry of Health (MOH) has developed the clinical practice guidelines on Anxiety Disorders to provide doctors and patients in Singapore with evidence-based treatment for anxiety disorders. This article reproduces the introduction and executive summary (with recommendations from the guidelines) from the MOH clinical practice guidelines on anxiety disorders, for the information of SMJ readers. Chapters and page numbers mentioned in the reproduced extract refer to the full text of the guidelines, which are available from the Ministry of Health website: http://www.moh.gov.sg/content/moh_web/healthprofessionalsportal/doctors/guidelines/cpg_medical.html. The recommendations should be used with reference to the full text of the guidelines. Following this article are multiple choice questions based on the full text of the guidelines.

1.1 Background information

Anxiety disorders are known to be one of the most prevalent of psychiatric conditions, yet they often remain under-diagnosed and under-treated. Their chronic, disabling symptoms cause considerable burden not only to sufferers but also to their families, and contribute to poorer quality of life and considerable economic burden on society.In many instances, there is a delay in seeking treatment and in some cases such delay may stretch up to nearly ten years. This may result from ignorance of the condition, fear of taking medications, and the stigma of receiving a psychiatric diagnosis, and or having to accept psychiatric treatment.The anxiety disorders include panic disorder with or without agoraphobia, social anxiety disorder, specific phobia, obsessive-compulsive disorder, generalised anxiety disorder, acute stress disorder and post-traumatic stress disorder. In the clinical evaluation of anxiety disorders, it is important to ascertain the type of anxiety disorder present. This would allow treatment to be targeted at the specific type of disorder.These guidelines are developed to provide practical, evidence-based recommendations to primary care physicians and specialists in psychiatry for the diagnosis and management of the anxiety disorders.The first edition of the guidelines was published in 2003. In this edition, we present data from newer research as well as older data not previously reported in the earlier guidelines.For example, we examine the efficacy of combining medications with psychological therapy over medications alone, or psychological therapy alone. In view of the majority of anxiety sufferers being female we have made recommendations for pharmacotherapy during pregnancy and breastfeeding. As these guidelines are intended for use in the Singapore context, we have omitted treatments that are currently not available in Singapore.

1.2 Aim

These guidelines are developed to facilitate the diagnosis and assessment of the anxiety disorders, and to ensure that their management is appropriate and effective.

1.3 Scope

These guidelines will cover the management of anxiety disorders in adults and address the issues of medication use during pregnancy and breastfeeding.

1.4 Target group

The content of the guidelines will be useful for all doctors treating patients with anxiety disorders. Efforts have been made to ensure that the guidelines are particularly useful for primary care physicians and specialists in psychiatry, including all those involved in the assessment and management of patients with anxiety disorders in the community. The doctor treating the patient is ultimately responsible for clinical decisions made after reviewing the individual patient’s history, clinical presentation and treatment options available.

1.5 Development of guidelines

These guidelines have been produced by a committee of psychiatrists, a clinical psychologist, pharmacist, patient representative, and family practitioners appointed by the Ministry of Health. They were developed by revising the existing guidelines, reviewing relevant literature, including overseas clinical practice guidelines, and by expert clinical consensus of professionals with experience in treating patients in the local setting.The following principles underlie the development of these guidelines:

• Treatment recommendations are supported by scientific evidence whenever possible (randomised controlled clinical trials represent the highest level of evidence) and expert clinical consensus is used when such data are lacking.
• Treatment should maximise therapeutic benefits and minimise side effects.

1.6 What’s new in the revised guidelines

This edition of the guidelines contains updated recommendations based on latest evidence, as well as detailed discussions and recommendations on the management of anxiety disorders in adult populations.The following represent changes to the revised guidelines

• An extensive review of the literature, including new evidence. This involved the re-writing and extensive revision of the chapters.
• Length of treatment, which provides answers to a pertinent question.
• Use of medications during pregnancy and breastfeeding. Given that females are more likely to be at risk of being diagnosed with anxiety disorders, this is an important subject.

We are aware that the Diagnostic and Statistical Manual of Mental Disorders-5 (DSM-5) was released in 2013. In DSM-5, post-traumatic stress disorder and obsessive-compulsive disorder have been removed and classified separately from the rest of the anxiety disorders. If we were to adhere strictly to DSM-5, this would entail omitting discussion on post-traumatic stress disorder and obsessive-compulsive disorder. As it is our aim to provide an update on the 2003 guidelines, post-traumatic stress disorder and obsessive-compulsive disorder have been included in this edition of the guidelines.In addition, anxiety conditions in children are included in DSM-5. Since the present guidelines are meant to address only adult anxiety disorders, guidelines on children’s anxiety conditions are not included here.Hence, for purposes of these guidelines, we will continue to use classifications based on the International Classification of Diseases-10 (ICD-10) and DSM-IV-TR criteria.

1.7 Review of guidelines

Evidence-based clinical practice guidelines are only as current as the evidence that supports them. Users must keep in mind that new evidence could supersede recommendations in these guidelines. The workgroup advises that these guidelines be scheduled for review five years after publication, or when new evidence appears that requires substantive changes to the present recommendations.     

Epinephrine injection therapy versus a combination of epinepnrine injection and endoscopic hemoclip in the treatment of bleeding ulcers

AIM: To assess the efficacy of hemoclip application in combination with epinephrine injection in the treatment of bleeding peptic ulcers and to compare the clinical outcomes between patients treated with such a combination therapy and those treated with epinephrine injection alone. METHODS: A total of 293 patients (211 males, 82 females) underwent endoscopic therapy for bleeding peptic ulcers. Of these, 202 patients (152 males, 50 females) received epinephrine injection therapy while 91 patients (59 males, 32 females) received combination therapy. The choice of endoscopic therapy was made by the endoscopist. Hemostatic rates, rebleeding rates, need for emergency surgery and 30-d mortality were the outcome measures studied. RESULTS: Patients who received combination therapy were significantly older (mean age 66±16 years, range 24-90 years) and more suffered from chronic renal failure compared to those who received epinephrine injection therapy alone (mean age 61±17 years, range 21-89 years). Failure to achieve permanent hemostasis was 4% in the group who received epinephrine injection alone and 11% in the group who received combination therapy. When the differences in age and renal function between the two treatment groups were taken into account by multivariate analysis, the rates of initial hemostasis, rebleeding rates, need for surgery and 30-d mortality for both treatment options were not significantly different. CONCLUSION: Combination therapy of epinephrine injection with endoscopic hemoclip application is an effective method of achieving hemostasis in bleeding peptic ulcer diseases. However, superiority of combination therapy over epinephrine injection alone, could not be demonstrated.