Association of germline variants in telomere maintenance genes (POT1, TERF2IP, ACD, and TERT) with spitzoid morphology in familial melanoma: A multi-center case series

Background

Spitzoid morphology in familial melanoma has been associated with germline variants in POT1, a telomere maintenance gene (TMG), suggesting a link between telomere biology and spitzoid differentiation.

Objective

To assess if familial melanoma cases associated with germline variants in TMG (POT1, ACD, TERF2IP, and TERT) commonly exhibit spitzoid morphology.

Methods

In this case series, melanomas were classified as having spitzoid morphology if at least 3 of 4 dermatopathologists reported this finding in ≥25% of tumor cells. Logistic regression was used to calculate odds ratios (OR) of spitzoid morphology compared to familial melanomas from unmatched noncarriers that were previously reviewed by a National Cancer Institute dermatopathologist.

Results

Spitzoid morphology was observed in 77% (23 of 30), 75% (3 of 4), 50% (2 of 4), and 50% (1 of 2) of melanomas from individuals with germline variants in POT1, TERF2IP, ACD, and TERT, respectively. Compared to noncarriers (n = 139 melanomas), POT1 carriers (OR = 225.1, 95% confidence interval: 51.7-980.5; P < .001) and individuals with TERF2IP, ACD, and TERT variants (OR = 82.4, 95% confidence interval: 21.3-494.6; P < .001) had increased odds of spitzoid morphology.

Limitations

Findings may not be generalizable to nonfamilial melanoma cases.

Conclusion

Spitzoid morphology in familial melanoma could suggest germline alteration of TMG.

Protocol for the implementation of a stepped-care model to address fear of cancer recurrence in patients previously diagnosed with early-stage (0-II) melanoma

INTRODUCTION

Fear of cancer recurrence (FCR) is commonly reported by patients diagnosed with early-stage (0-II) melanoma and can have a significant impact on daily functioning. This study will pilot the implementation of the Melanoma Care Program, an evidence-based, psychological intervention to reduce FCR, into routine practice, using a stepped-care model.

METHODS AND ANALYSIS

Intervention effectiveness and level of implementation will be investigated using a hybrid type I design. Between 4 weeks before and 1 week after their next dermatological appointment, patients with melanoma will be invited to complete the Fear of Cancer Recurrence Inventory Short-Form, measuring self-reported FCR severity. Using a stepped-care model, clinical cut-off points will guide the level of support offered to patients. This includes: (1) usual care, (2) Melanoma: Questions and Answers psychoeducational booklet, and (3) three or five psychotherapeutic telehealth sessions. This longitudinal, mixed-methods pilot implementation study aims to recruit 108 patients previously diagnosed with stage 0-II melanoma. The primary effectiveness outcome is change in FCR severity over time. Secondary effectiveness outcomes include change in anxiety, depression, stress, health-related quality of life and melanoma-related knowledge over time. All outcomes are measured at baseline, within 1 week of the final telehealth session, and 6 and 12 months post-intervention. Implementation stakeholders at each study site and interested patients will provide feedback on intervention acceptability and appropriateness. Implementation stakeholders will also provide feedback on intervention cost, feasibility, fidelity and sustainability. These outcomes will be measured throughout implementation, using questionnaires and semistructured interviews/expert group discussions. Descriptive statistics, linear mixed-effects regression and thematic analysis will be used to analyse study data.

ETHICS AND DISSEMINATION

Ethics approval was granted by the Sydney Local Health District-Royal Prince Alfred Zone (2020/ETH02518), protocol number: X20-0495. Results will be disseminated through peer-reviewed journals, conference presentations, social media and result summaries distributed to interested participants. TRIAL REGISTRATION DETAILS: (ACTRN12621000145808).

Efficiency of Detecting New Primary Melanoma Among Individuals Treated in a High-risk Clinic for Skin Surveillance

Importance

A previous single-center study observed fewer excisions, lower health care costs, thinner melanomas, and better quality of life when surveillance of high-risk patients was conducted in a melanoma dermatology clinic with a structured surveillance protocol involving full-body examinations every 6 months aided by total-body photography (TBP) and sequential digital dermoscopy imaging (SDDI).

Objective

To examine longer-term sustainability and expansion of the surveillance program to numerous practices, including a primary care skin cancer clinic setting.

Design, Setting, and Participants

This prospective cohort study recruited 593 participants assessed from 2012 to 2018 as having very high risk of melanoma, with a median of 2.9 years of follow-up (interquartile range, 1.9-3.3 years), from 4 melanoma high-risk clinics (3 dermatology clinics and 1 primary care skin cancer clinic) in New South Wales, Australia. Data analyses were conducted from February to September 2020.

Exposures

Six-month full-body examination with the aid of TBP and SDDI. For equivocal lesions, the clinician performed SDDI at 3 or 6 months.

Main Outcomes and Measures

All suspect monitored or excised lesions were recorded, and pathology reports obtained. Outcomes included the incidence and characteristics of new lesions and the association of diagnostic aids with rates of new melanoma detection.

Results

Among 593 participants, 340 (57.3%) were men, and the median age at baseline was 58 years (interquartile range, 47-66 years). There were 1513 lesions excised during follow-up, including 171 primary melanomas. The overall benign to malignant excision ratio, including keratinocyte carcinomas, was 0.8:1.0; the benign melanocytic to melanoma excision ratio was 2.4:1.0; and the melanoma in situ to invasive melanoma ratio was 2.2:1.0. The excision ratios were similar across the 4 centers. The risk of developing a new melanoma was 9.0% annually in the first 2 years and increased with time, particularly for those with multiple primary melanomas. The thicker melanomas (>1-mm Breslow thickness; 7 of 171 melanomas [4.1%]) were mostly desmoplastic or nodular (4 of 7), self-detected (2 of 7), or clinician detected without the aid of TBP (3 of 7). Overall, new melanomas were most likely to be detected by a clinician with the aid of TBP (54 of 171 [31.6%]) followed by digital dermoscopy monitoring (50 of 171 [29.2%]).

Conclusions and Relevance

The structured surveillance program for high-risk patients may be implemented at a larger scale given the present cohort study findings suggesting the sustainability and replication of results in numerous settings, including a primary care skin cancer clinic.

Australian general practitioners' attitudes and knowledge of sentinel lymph node biopsy in melanoma management

BACKGROUND AND OBJECTIVES

In Australia, the uptake of the sentinel lymph node biopsy (SLNB) appears low despite clinical practice guideline recommendations. The aim of this study was to describe the knowledge and attitudes of general practitioners (GPs) to SLNB.

METHOD

GPs were recruited at an annual conference and a skin cancer skills workshop, and using GP professional communications. A mixed methods approach comprised a cross-sectional questionnaire and, for a subset of participants, semi-structured interviews.

RESULTS

Overall, 231 GPs completed the questionnaire, of whom 23 were interviewed. One-third (32%) described themselves as quite or very familiar with the guidelines, and two-thirds (68%) thought that SLNB had an important role in the management of patients with melanoma. Of GPs who would discuss SLNB with eligible patients, <40% correctly identified that SLNB is recommended for patients with an invasive melanoma >1 mm thick.

DISCUSSION

GPs were generally supportive of SLNB. Familiarity with the guidelines was low, particularly regarding which patients should be considered for SLNB.

Birth cohort-specific trends of sun-related behaviors among individuals from an international consortium of melanoma-prone families

BACKGROUND

Individuals from melanoma-prone families have similar or reduced sun-protective behaviors compared to the general population. Studies on trends in sun-related behaviors have been temporally and geographically limited.

METHODS

Individuals from an international consortium of melanoma-prone families (GenoMEL) were retrospectively asked about sunscreen use, sun exposure (time spent outside), sunburns, and sunbed use at several timepoints over their lifetime. Generalized linear mixed models were used to examine the association between these outcomes and birth cohort defined by decade spans, after adjusting for covariates.

RESULTS

A total of 2407 participants from 547 families across 17 centers were analyzed. Sunscreen use increased across subsequent birth cohorts, and although the likelihood of sunburns increased until the 1950s birth cohort, it decreased thereafter. Average sun exposure did not change across the birth cohorts, and the likelihood of sunbed use increased in more recent birth cohorts. We generally did not find any differences in sun-related behavior when comparing melanoma cases to non-cases. Melanoma cases had increased sunscreen use, decreased sun exposure, and decreased odds of sunburn and sunbed use after melanoma diagnosis compared to before diagnosis.

CONCLUSIONS

Although sunscreen use has increased and the likelihood of sunburns has decreased in more recent birth cohorts, individuals in melanoma-prone families have not reduced their overall sun exposure and had an increased likelihood of sunbed use in more recent birth cohorts. These observations demonstrate partial improvements in melanoma prevention and suggest that additional intervention strategies may be needed to achieve optimal sun-protective behavior in melanoma-prone families.

Knowledge and attitudes of Australian dermatologists towards sentinel lymph node biopsy for melanoma: a mixed methods study

BACKGROUND/OBJECTIVES

In melanoma management, sentinel lymph node biopsy (SLNB) is used to stage patients and to indicate prognosis. More recently, it has been used to select patients for adjuvant therapy. This study aimed to report knowledge of and attitudes towards SLNB for patients with melanoma among Australian dermatologists.

METHODS

Mixed methods study using cross-sectional questionnaires (n = 88) and semi-structured interviews (n = 13), May-September 2019.

RESULTS

Of the dermatologists surveyed, 56% thought SLNB had an important role in melanoma management, 26% were unsure and 18% thought SLNB unimportant. Of the 92% who would discuss SLNB with their patients, the main stated value of SLNB was for assessing eligibility for adjuvant therapies (79%); only 60% indicated SLNB was of value for providing prognostic information, and just over half (53%) thought it could improve staging. Interview data indicated that attitudes towards SLNB are shifting among dermatologists, driven by data from landmark clinical trials and the influence of professional networks. Accordingly, interviewees adopted one of three positions in relation to SLNB: (a) believed in utility of SLNB and adhered to the guidelines; (b) were unconvinced about utility of SLNB but adhered to the guidelines; and (c) were unconvinced about utility of SLNB and did not adhere to the guidelines.

CONCLUSION

Although most of the dermatologists surveyed were familiar with and follow the SLNB recommendations, some disagreement with and distrust of the recommendations was evident. Greater acceptance of the SLNB recommendations appeared to be driven by the improved outcomes demonstrated in stage III patients receiving adjuvant systemic therapy.

FRAMe: Familial Risk Assessment of Melanoma-a risk prediction tool to guide CDKN2A germline mutation testing in Australian familial melanoma

Germline mutations in CDKN2A greatly increase risk of developing cutaneous melanoma. We have constructed a risk prediction model, Familial Risk Assessment of Melanoma (FRAMe), for estimating the likelihood of carrying a heritable CDKN2A mutation among Australian families, where the prevalence of these mutations is low. Using logistic regression, we analysed characteristics of 299 Australian families recruited through the Sydney site of GenoMEL (international melanoma genetics consortium) with at least three cases of cutaneous melanoma (in situ and invasive) among first-degree blood relatives, for predictors of the presence of a pathogenic CDKN2A mutation. The final multivariable prediction model was externally validated in an independent cohort of 61 melanoma kindreds recruited through GenoMEL Queensland. Family variables independently associated with the presence of a CDKN2A mutation in a multivariable model were number of individuals diagnosed with melanoma under 40 years of age, number of individuals diagnosed with more than one primary melanoma, and number of individuals blood related to a melanoma case in the first degree diagnosed with any cancer excluding melanoma and non-melanoma skin cancer. The number of individuals diagnosed with pancreatic cancer was not independently associated with mutation status. The risk prediction model had an area under the receiver operating characteristic curve (AUC) of 0.851 (95% CI 0.793, 0.909) in the training dataset, and 0.745 (95%CI 0.612, 0.877) in the validation dataset. This model is the first to be developed and validated using only Australian data, which is important given the higher rate of melanoma in the population. This model will help to effectively identify families suitable for genetic counselling and testing in areas of high ambient ultraviolet radiation. A user-friendly electronic nomogram is available at www.melanomarisk.org.au .

AB0029 INHIBITION OF EFFECTOR B CELLS BY IBRUTINIB IN SYSTEMIC SCLEROSIS

Background:

Systemic sclerosis (SSc) is a connective tissue disease with significant morbidity and mortality. Effective treatment is still missing, and clinical control of the disease remains challenging. In particular, the development of pulmonary and cardiac fibrosis and pulmonary hypertension are severe complications responsible for excessive mortality. Currently available treatment strategies – besides aggressive autologous stem cell transplantation which is an option only for selected patients – only alleviate symptoms and slow disease progression. Previous attempts of immunomodulating therapies addressing B cell pathology like rituximab and tocilizumab in SSc showed mixed efficacy1,2

Objectives:

Here, we investigated the therapeutic potential of ibrutinib, a Bruton’s tyrosine kinase (BTK) inhibitor used in B cell malignancies, to alter B cell pathology in SSc in anin vitromodel of autoimmunity.

Methods:

PBMCs and sorted B cells of 24 patients with SSc were used for functional testing after stimulation with hypomethylated DNA fragments (CpG) to induce an innate immune response. The effects of ibrutinib on cytokine production, autoantibody release and activation of the transcription factor NFκB were evaluated via multiplex cytokine assay, ELISA and flow cytometry.

Results:

Ibrutinib was able to reduce the production of the profibrotic hallmark cytokines IL-6 and TNF-α, which are mainly released by the effector B cell population, in response to TLR9-stimulation. Importantly, small doses of ibrutinib (0.1 µM) preserved the production of immunoregulatory IL-10 and IFN-γ while effectively inhibiting the cardinal cytokines of hyperactivated profibrotic effector B cells in SSc. Intracellular cytokine staining of IL-6 in B cell subsets further endorsed the potential of ibrutinib to inhibit B cells in a subset-specific manner, reducing IL-6+naïve B cells significantly but not IL-6+memory B cells. The subset specificity was abolished when high doses of ibrutinib (10 µM) were applied. In a flow cytometry analysis of phosphorylated NFκB, an important transcription factor in the induction of innate immune responses in B cells, significantly less activation was observed with ibrutinib treatment (0.1 µM). Higher doses of ibrutinib were unable to further reduce the abundance of pNFκB.

Conclusion:

Our data could pave the avenue for a clinical application of ibrutinib for patients with SSc as a novel treatment option for the underlying pathogenetic immune imbalance contributing to disease onset and progression.

References:

[1]Khanna, D.et al.Efficacy and Safety of Tocilizumab for the Treatment of Systemic Sclerosis: Results from a Phase 3 Randomized Controlled Trial [abstract]. Arthritis Rheumatol. 2018; 70 (suppl 10).

[2]Jordan, S.et al.Effects and safety of rituximab in systemic sclerosis: an analysis from the European Scleroderma Trial and Research (EUSTAR) group.Ann. Rheum. Dis.74, 1188–1194 (2015).

Disclosure of Interests:

Jakob Einhaus: None declared, Ann-Christin Pecher: None declared, Elisa Asteriti: None declared, Hannes Schmid: None declared, Kathy-Ann Secker: None declared, Silke Duerr-Stoerzer: None declared, Hildegard Keppeler: None declared, Reinhild Klein: None declared, Corina Schneidawind: None declared, Jörg Henes Grant/research support from: Novartis, Roche-Chugai, Consultant of: Novartis, Roche, Celgene, Pfizer, Abbvie, Sanofi, Boehringer-Ingelheim,, Dominik Schneidawind: None declared

Development and external validation study of a melanoma risk prediction model incorporating clinically assessed naevi and solar lentigines

BACKGROUND

Melanoma risk prediction models could be useful for matching preventive interventions to patients' risk.

OBJECTIVES

To develop and validate a model for incident first-primary cutaneous melanoma using clinically assessed risk factors.

METHODS

We used unconditional logistic regression with backward selection from the Australian Melanoma Family Study (461 cases and 329 controls) in which age, sex and city of recruitment were kept in each step, and we externally validated it using the Leeds Melanoma Case-Control Study (960 cases and 513 controls). Candidate predictors included clinically assessed whole-body naevi and solar lentigines, and self-assessed pigmentation phenotype, sun exposure, family history and history of keratinocyte cancer. We evaluated the predictive strength and discrimination of the model risk factors using odds per age- and sex-adjusted SD (OPERA) and the area under curve (AUC), and calibration using the Hosmer-Lemeshow test.

RESULTS

The final model included the number of naevi ≥ 2 mm in diameter on the whole body, solar lentigines on the upper back (a six-level scale), hair colour at age 18 years and personal history of keratinocyte cancer. Naevi was the strongest risk factor; the OPERA was 3·51 [95% confidence interval (CI) 2·71-4·54] in the Australian study and 2·56 (95% CI 2·23-2·95) in the Leeds study. The AUC was 0·79 (95% CI 0·76-0·83) in the Australian study and 0·73 (95% CI 0·70-0·75) in the Leeds study. The Hosmer-Lemeshow test P-value was 0·30 in the Australian study and < 0·001 in the Leeds study.

CONCLUSIONS

This model had good discrimination and could be used by clinicians to stratify patients by melanoma risk for the targeting of preventive interventions. What's already known about this topic? Melanoma risk prediction models may be useful in prevention by tailoring interventions to personalized risk levels. For reasons of feasibility, time and cost many melanoma prediction models use self-assessed risk factors. However, individuals tend to underestimate their naevus numbers. What does this study add? We present a melanoma risk prediction model, which includes clinically-assessed whole-body naevi and solar lentigines, and self-assessed risk factors including pigmentation phenotype and history of keratinocyte cancer. This model performs well on discrimination, the model's ability to distinguish between individuals with and without melanoma, and may assist clinicians to stratify patients by melanoma risk for targeted preventive interventions.

Evaluation of the contribution of germline variants in BRCA1 and BRCA2 to uveal and cutaneous melanoma

Germline mutations of BRCA1 and BRCA2 predispose individuals to a high risk of breast and ovarian cancer, and elevated risk of other cancers, including those of the pancreas and prostate. BRCA2 mutation carriers may have increased risk of uveal melanoma (UM) and cutaneous melanoma (CM), but associations with these cancers in BRCA1 mutation carriers have been mixed. Here, we further assessed whether UM and CM are associated with BRCA1 or BRCA2 by assessing the presence, segregation and reported/predicted pathogenicity of rare germline mutations (variant allele frequency < 0.01) in families with multiple members affected by these cancers. Whole-genome or exome sequencing was performed on 160 CM and/or UM families from Australia, the Netherlands, Denmark and Sweden. Between one and five cases were sequenced from each family, totalling 307 individuals. Sanger sequencing was performed to validate BRCA1 and BRCA2 germline variants and to assess carrier status in other available family members. A nonsense and a frameshift mutation were identified in BRCA1, both resulting in premature truncation of the protein (the first at p.Q516 and the second at codon 91, after the introduction of seven amino acids due to a frameshift deletion). These variants co-segregated with CM in individuals who consented for testing and were present in individuals with pancreatic, prostate and breast cancer in the respective families. In addition, 33 rare missense mutations (variant allele frequency ranging from 0.00782 to 0.000001 in the aggregated ExAC data) were identified in 34 families. Examining the previously reported evidence of functional consequence of these variants revealed all had been classified as either benign or of unknown consequence. Seeking further evidence of an association between BRCA1 variants and melanoma, we examined two whole-genome/exome sequenced collections of sporadic CM patients (total N = 763). We identified one individual with a deleterious BRCA1 variant, however, this allele was lost (with the wild-type allele remaining) in the corresponding CM, indicating that defective BRCA1 was not a driver of tumorigenesis in this instance. Although this is the first time that deleterious BRCA1 mutations have been described in high-density CM families, we conclude that there is an insufficient burden of evidence to state that the increased familial CM or UM susceptibility is because of these variants. In addition, in conjunction with other studies, we conclude that the previously described association between BRCA2 mutations and UM susceptibility represents a rare source of increased risk.

Associations of pigmentary and naevus phenotype with melanoma risk in two populations with comparable ancestry but contrasting levels of ambient sun exposure

BACKGROUND

People at high risk of developing melanoma are usually identified by pigmentary and naevus phenotypes.

OBJECTIVE

We examined whether associations of these phenotypes with melanoma risk differed by ambient sun exposure or participant characteristics in two population-based, case-control studies with comparable ancestry but different ambient sun exposure.

METHODS

Data were analysed from 616 cases and 496 controls from the Australian Melanoma Family Study and 2012 cases and 504 controls from the Leeds (UK) case-control study. Questionnaire, interview and dermatological skin examination data were collected using the same measurement protocols. Relative risks were estimated as odds ratios using unconditional logistic regression, adjusted for potential confounders.

RESULTS

Hair and skin colour were the strongest pigmentary phenotype risk factors. All associations of pigmentary phenotype with melanoma risk were similar across countries. The median number of clinically assessed naevi was approximately three times higher in Australia than Leeds, but the relative risks for melanoma associated with each additional common or dysplastic naevus were higher for Leeds than Australia, especially for naevi on the upper and lower limbs. Higher naevus counts on the head and neck were associated with a stronger relative risk for melanoma for women than men. The two countries had similar relative risks for melanoma based on self-reported naevus density categories, but personal perceptions of naevus number differed by country. There was no consistent evidence of interactions between phenotypes on risk.

CONCLUSIONS

Classifying people at high risk of melanoma based on their number of naevi should ideally take into account their country of residence, type of counts (clinical or self-reported), body site on which the naevus counts are measured and sex. The presence of naevi may be a stronger indicator of a genetic predisposition in the UK than in Australia based on less opportunity for sun exposure to influence naevus development.

Sunscreen Use and Melanoma Risk Among Young Australian Adults

Importance

There are limited data among young adults on sunscreen use during childhood and adulthood and on the association of sunscreen use with melanoma risk.

Objective

To assess correlates of early-life sunscreen use and the association between sunscreen use and risk of cutaneous melanoma before age 40 years.

Design, Setting, and Participants

This population-based, case-control family study analyzed Australian Melanoma Family Study data for persons with questionnaire data on sunscreen use collected by interview from 2001 to 2005 across 3 states in Australia, representing two-thirds of the country's population. Case participants (aged 18-39 years) had confirmed first primary melanoma. Siblings of case participants were included, and case participants without a sibling control were excluded. Unrelated controls (aged 18-44 years) were recruited from the electoral roll or were a spouse, partner, or friend nominated by case participants. Data analyses were conducted from October 2017 to February 2018.

Exposures

Self- and parent-reported sunscreen use, sun exposure, and other candidate risk factors during childhood and adulthood.

Main Outcomes and Measures

Logistic regression analyses adjusted for potential confounders were used to estimate odds ratios (ORs) for melanoma and for correlates of sunscreen use.

Results

Participation was 629 of 830 contactable cases (76%) (629 of 1197 overall [53%]), 240 of 570 contactable controls (42%) from the electoral roll (240 of 1068 overall [23%]), and 295 of 371 nominated spouse or friend controls (80%); analysis incuded 603 cases and 1088 controls. The median (interquartile range) age was 32 (28-36) years for 603 cases, 35 (30-38) years for 478 unrelated controls, and 34 (29-38) years for 610 sibling controls. There were more women than men (range, 57%-62%) in all groups, approximately 40% (range, 39%-43%) of participants had a university education, and most participants (range, 58%-73%) had British/northern European ethnicity. Risk of melanoma was less with higher use of sunscreen in childhood (OR for highest vs lowest tertiles, 0.60; 95% CI, 0.42-0.87; P = .02 for trend) and across the lifetime (OR, 0.65; 95% CI, 0.45-0.93; P = .07 for trend). Subgroup analyses suggested that the protective association of sunscreen with melanoma was stronger for people reporting blistering sunburn, receiving a diagnosis of melanoma at a younger age, or having some or many nevi. Total lifetime sun exposure was unrelated to melanoma risk (OR for highest vs lowest tertile, 0.97; 95% CI, 0.66-1.43; P = .94 for trend). By contrast, total sun exposure inversely weighted by sunscreen use (as a measure of sun exposure unprotected by sunscreen) was significantly associated with melanoma risk (OR, 1.80; 95% CI, 1.22-2.65; P = .007 for trend) and appeared stronger for people having lighter pigmentation or some or many nevi or using sunscreen to stay longer in the sun. Regular users of sunscreen were more likely to be female, younger, and of British or northern European ancestry and to have higher educational levels, lighter skin pigmentation, and a stronger history of blistering sunburn.

Conclusions and Relevance

Our findings provided evidence that regular sunscreen use is significantly associated with reduced risk of cutaneous melanoma among young adults and identified several characteristics associated with less sunscreen use.

Estimating CDKN2A mutation carrier probability among global familial melanoma cases using GenoMELPREDICT

BACKGROUND

Although rare in the general population, highly penetrant germline mutations in CDKN2A are responsible for 5%-40% of melanoma cases reported in melanoma-prone families. We sought to determine whether MELPREDICT was generalizable to a global series of families with melanoma and whether performance improvements can be achieved.

METHODS

In total, 2116 familial melanoma cases were ascertained by the international GenoMEL Consortium. We recapitulated the MELPREDICT model within our data (GenoMELPREDICT) to assess performance improvements by adding phenotypic risk factors and history of pancreatic cancer. We report areas under the curve (AUC) with 95% confidence intervals (CIs) along with net reclassification indices (NRIs) as performance metrics.

RESULTS

MELPREDICT performed well (AUC 0.752, 95% CI 0.730-0.775), and GenoMELPREDICT performance was similar (AUC 0.748, 95% CI 0.726-0.771). Adding a reported history of pancreatic cancer yielded discriminatory improvement (P < .0001) in GenoMELPREDICT (AUC 0.772, 95% CI 0.750-0.793, NRI 0.40). Including phenotypic risk factors did not improve performance.

CONCLUSION

The MELPREDICT model functioned well in a global data set of familial melanoma cases. Adding pancreatic cancer history improved model prediction. GenoMELPREDICT is a simple tool for predicting CDKN2A mutational status among melanoma patients from melanoma-prone families and can aid in directing these patients to receive genetic testing or cancer risk counseling.

III-V heterostructure tunnel field-effect transistor

The tunnel field-effect transistor (TFET) is regarded as one of the most promising solid-state switches to overcome the power dissipation challenge in ultra-low power integrated circuits. TFETs take advantage of quantum mechanical tunneling hence exploit a different current control mechanism compared to standard MOSFETs. In this review, we describe state-of-the-art development of TFET both in terms of performances and of materials integration and we identify the main remaining technological challenges such as heterojunction defects and oxide/channel interface traps causing trap-assisted-tunneling (TAT). Mesa-structures, planar as well as vertical geometries are examined. Conductance slope analysis on InAs/GaSb nanowire tunnel diodes are reported, these two-terminal measurements can be relevant to investigate the tunneling behavior. A special focus is dedicated to III-V heterostructure TFET, as different groups have recently shown encouraging results achieving the predicted sub-thermionic low-voltage operation.

Structure and chemistry of interfaces between ceria and yttria-stabilized zirconia studied by analytical STEM

Epitaxial undoped and Gd₂O₃-doped ceria films were grown by pulsed laser deposition on (1 1 1) faced Y₂O₃-stabilized zirconia (YSZ). Highly localized cerium reduction at the film-substrate interfaces is revealed by atomically resolved valence EELS mapping using C_s aberration-corrected scanning transmission electron microscopy. The chemical profiles reveal interdiffusion of Ce, (Gd), Y, Zr, forming an intermixing zone at the interface 7-9 (1 1 1) lattice planes wide. In its vicinity, the fraction of Ce³⁺ raises gradually over 6-8 lattice planes from zero in the bulk ceria to ≈100% in one single plane at the interface. Beyond this plane the Ce³⁺ fraction drops sharply within the YSZ substrate. In the vicinity of the interface systematic scan deflections are observed during EELS line scans. The advancing electron probe experiences a retarding force at the ceria side, and an accelerating force at the YSZ side, irrespective of the scan direction. This behavior is suggestive of coulombic interactions between the electron probe and a charged interface. This is interpreted as an indication of the presence of a space-charge situation at the YSZ/ceria interface, resulting from an excess negative charge at the ceria side (due to Ce³⁺cations) and an excess positive charge at the YSZ side (due to oxygen vacancies).

Unsteady walking as a symptom in type 2 diabetes mellitus: independent association with depression and sedentary lifestyle and no association with diabetic neuropathy

The purpose of this study was to look at the determinants of the unsteady walking (UW) symptom in patients with type 2 diabetes mellitus (T2DM) by defining if UW and/or the Diabetic Neuropathy Symptoms Score (DNSS) are associated with positive scores in Beck's Depression Inventory (BDI) and with a positive Michigan Neuropathy Screening Instrument score (MNSI). We evaluated 203 T2DM patients without visible gait disturbances. They were divided into UW (+) and UW (−) or DNSS (+) and DNSS (−) according to symptoms. We found a prevalence of 48.3% for UW (+) and of 63% for DNSS (+) in our sample. In univariate analysis, the presence of UW was significantly associated with waist circumference (P=0.024), number of comorbidities (P=0.012), not practicing physical exercise (P=0.011), positive BDI score (P=0.003), presence of neuropathic symptoms by the MNSI questionnaire (P<0.001), and positive diabetic neuropathy screening by MNSI (P=0.021). In multivariate analysis, UW (used as a dependent variable) was independently associated with a positive BDI score (P<0.001; 95%CI=1.01-1.03), T2DM duration (P=0.023; 95%CI=1.00–1.03), number of co-morbidities (P=0.032; 95%CI=1.01–1.37), and a sedentary lifestyle (P=0.025; 95%CI=1.06–2.5). The UW symptom and a positive DNSS are more closely related to a positive score for depression than to presence of neuropathy in T2DM.

[Marginal protection of retinal cells by bisperoxovanadium : Appropriate therapy in the model of retinal ischemia?]

BACKGROUND

Ischemic processes usually lead to the destruction of retinal cells and therefore play a key role in a multitude of eye diseases.

OBJECTIVE

The aim of this study was to investigate whether bisperoxovanadium has a potential neuroprotective effect in an ischemia/reperfusion animal model.

MATERIAL AND METHODS

Initially, ischemia was induced in one eye of an ischemia/reperfusion model and 3 days later, a 14-day medication-based treatment was initiated. Bisperoxovanadium was administered intraperitoneally every 3 days. Subsequently, the number of ganglion cells, the rate of apoptosis, amacrine cells, macroglia, microglia, and their activation state, as well as photoreceptors were determined by histological and immunohistochemical analyses.

RESULTS

In comparison to the control group, a significant retinal ganglion cell loss, a significant reduction of the inner layers as well as a decrease in photoreceptor and amacrine cell numbers could be determined in the ischemic eyes. In addition, there was an increase in the number of microglia in these animals. The rats treated with bisperoxovanadium did not exhibit a significant neuroprotective effect regarding the number of ganglion cells, the rate of apoptosis, macroglia, amacrine cells, or photoreceptors; however, a low structural degeneration of photoreceptors could be observed as an effect of the treatment. Additionally, fewer microglia and activated microglia were observed after bisperoxovanadium treatment.

CONCLUSION

Bisperoxovanadium seems to have only a marginal neuroprotective effect on ischemic retinae. It needs to be examined whether earlier therapy onset, higher dose or different route of administration would significantly improve the results or whether this therapeutic approach is unsuitable.

Manipulating Surface States of III-V Nanowires with Uniaxial Stress

III-V compound semiconductors are indispensable materials for today's high-end electronic and optoelectronic devices and are being explored for next-generation transistor logic and quantum technologies. III-V surfaces and interfaces play the leading role in determining device performance, and therefore, methods to control their electronic properties have been developed. Typically, surface passivation studies demonstrated how to limit the density of surface states. Strain has been widely used to improve the electronic transport properties and optoelectronic properties of III-Vs, but the potential of this technology to modify the surface properties still remains to be explored. Here we show that uniaxial stress induces a shift in the energy of the surface states of III-V nanowires, modifying their electronic properties. We demonstrate this phenomenon by modulating the conductivity of InAs nanowires over 4 orders of magnitude with axial strain ranging between -2.5% in compression and 2.1% in tension. The band bending at the surface of the nanostructure is modified from accumulation to depletion reversibly and reproducibly. We provide evidence of this physical effect using a combination of electrical transport measurement, Raman spectroscopy, band-structure modeling, and technology computer aided design (TCAD) simulations. With this methodology, the deformation potentials for the surface states are quantified. These results reveal that strain technology can be used to shift surface states away from energy ranges in which device performance is negatively affected and represent a novel route to engineer the electronic properties of III-V devices.

Association of daptomycin use with resistance development in Enterococcus faecium bacteraemia-a 7-year individual and population-based analysis

OBJECTIVE

In this study we aimed to analyse the association between use of daptomycin and MICs of daptomycin in Enterococcus faecium bacteraemia.

METHODS

We prospectively enrolled patients aged ≥18 years with E. faecium bacteraemia hospitalized at the University Hospital Basel from 2008 to 2014. We determined daptomycin MICs by Etests and used pulsed field gel electrophoresis to determine clonal relatedness. We recorded the defined daily dosages of daptomycin (DDDs) per 100 patient-days and clinical data from charts. We correlated daptomycin MIC with use of daptomycin in patients with recurrence/persistence.

RESULTS

In 195 E. faecium bacteraemias originating from 162 patients the median MIC for daptomycin was 2 mg/L (IQR 2-3); 30% (15.4%) isolates had a MIC ≥4 mg/L and 6 (3.1%) were resistant (MIC >4 mg/L) according to CLSI criteria. The usage of daptomycin increased more than four-fold from 0.36 DDDs/100 patient-days in 2008 to 1.6 in 2014. In 13 of 28 (42.9%) patients with a relapsing or persisting bacteraemia, the daptomycin MIC of the second isolate increased from a median of 2.0 to 2.5 mg/L (p 0.010); 3/13 (23.1%) developed resistance. All patients with the same clone in the first and second episode and an increase of daptomycin MIC had been treated with daptomycin (6/6 versus 1/7 p 0.005).

CONCLUSIONS

Daptomycin MICs and Daptomycin usage increased over time. On an individual patient level daptomycin exposure was associated with an increased MIC in subsequent bacteraemia episodes. Diversity did not indicate a clonal origin and argues for a de novo development of resistance.

Nonsense mutations in the shelterin complex genes ACD and TERF2IP in familial melanoma

BACKGROUND

The shelterin complex protects chromosomal ends by regulating how the telomerase complex interacts with telomeres. Following the recent finding in familial melanoma of inactivating germline mutations in POT1, encoding a member of the shelterin complex, we searched for mutations in the other five components of the shelterin complex in melanoma families.

METHODS

Next-generation sequencing techniques were used to screen 510 melanoma families (with unknown genetic etiology) and control cohorts for mutations in shelterin complex encoding genes: ACD, TERF2IP, TERF1, TERF2, and TINF 2. Maximum likelihood and LOD [logarithm (base 10) of odds] analyses were used. Mutation clustering was assessed with χ(2) and Fisher's exact tests. P values under .05 were considered statistically significant (one-tailed with Yates' correction).

RESULTS

Six families had mutations in ACD and four families carried TERF2IP variants, which included nonsense mutations in both genes (p.Q320X and p.R364X, respectively) and point mutations that cosegregated with melanoma. Of five distinct mutations in ACD, four clustered in the POT1 binding domain, including p.Q320X. This clustering of novel mutations in the POT1 binding domain of ACD was statistically higher (P = .005) in melanoma probands compared with population control individuals (n = 6785), as were all novel and rare variants in both ACD (P = .040) and TERF2IP (P = .022). Families carrying ACD and TERF2IP mutations were also enriched with other cancer types, suggesting that these variants also predispose to a broader spectrum of cancers than just melanoma. Novel mutations were also observed in TERF1, TERF2, and TINF2, but these were not convincingly associated with melanoma.

CONCLUSIONS

Our findings add to the growing support for telomere dysregulation as a key process associated with melanoma susceptibility.

Accuracy of self-reported nevus and pigmentation phenotype compared with clinical assessment in a population-based study of young Australian adults

BACKGROUND

Awareness of individual risk may encourage improved prevention and early detection of melanoma.

METHODS

We evaluated the accuracy of self-reported pigmentation and nevus phenotype compared with clinical assessment, and examined agreement between nevus counts from selected anatomical regions. The sample included 456 cases with invasive cutaneous melanoma diagnosed between ages 18 to 39 years and 538 controls from the population-based Australian Melanoma Family Study. Participants completed a questionnaire about their pigmentation and nevus phenotype, and attended a dermatologic skin examination.

RESULTS

There was strong agreement between self-reported and clinical assessment of eye color [κ, = 0.78; 95% confidence interval (CI), 0.74-0.81]; and moderate agreement for hair color (κ = 0.46; 95% CI, 0.42-0.50). Agreement between self-reported skin color and spectrophotometer-derived measurements was poor (κ = 0.12; 95% CI, 0.08-0.16) to moderate (Spearman correlation rs = -0.37; 95% CI, -0.32 to -0.42). Participants tended to underestimate their nevus counts and pigmentation; men were more likely to underreport their skin color. The rs was 0.43 (95% CI, 0.38-0.49) comparing clinical total body nevus counts with self-reported nevus categories. There was good agreement between total body nevus counts and site-specific nevus counts, particularly on both arms.

CONCLUSIONS

Young adults have suboptimal accuracy when assessing important risk characteristics including nevus numbers and pigmentation. Measuring nevus count on the arms is a good predictor of full body nevus count.

IMPACT

These results have implications for the likely success of targeted public health programs that rely on self-assessment of these factors.

Prevalence and predictors of germline CDKN2A mutations for melanoma cases from Australia, Spain and the United Kingdom

BACKGROUND

Mutations in the CDKN2A and CDK4 genes predispose to melanoma. From three case-control studies of cutaneous melanoma, we estimated the prevalence and predictors of these mutations for people from regions with widely differing latitudes and melanoma incidence.

METHODS

Population-based cases and controls from the United Kingdom (1586 cases, 499 controls) and Australia (596 early-onset cases, 476 controls), and a hospital-based series from Spain (747 cases, 109 controls), were screened for variants in all exons of CDKN2A and the p16INK4A binding domain of CDK4.

RESULTS

The prevalence of mutations for people with melanoma was similar across regions: 2.3%, 2.5% and 2.0% for Australia, Spain and the United Kingdom respectively. The strongest predictors of carrying a mutation were having multiple primaries (odds ratio (OR) = 5.4, 95% confidence interval (CI: 2.5, 11.6) for 2 primaries and OR = 32.4 (95% CI: 14.7, 71.2) for 3 or more compared with 1 primary only); and family history (OR = 3.8; 95% CI:1.89, 7.5) for 1 affected first- or second-degree relative and OR = 23.2 (95% CI: 11.3, 47.6) for 2 or more compared with no affected relatives). Only 1.1% of melanoma cases with neither a family history nor multiple primaries had mutations.

CONCLUSIONS

There is a low probability (<2%) of detecting a germline CDKN2A mutation in people with melanoma except for those with a strong family history of melanoma (≥2 affected relatives, 25%), three or more primary melanomas (29%), or more than one primary melanoma who also have other affected relatives (27%).

Full thermoelectric characterization of InAs nanowires using MEMS heater/sensors

Precise measurements of a complete set of thermoelectric parameters on a single indium-arsenide nanowire (NW) have been performed using highly sensitive, micro-fabricated sensing devices based on the heater/sensor principle. The devices were fabricated as micro electro-mechanical systems consisting of silicon nitride membranes structured with resistive gold heaters/sensors. Preparation, operation and characterization of the devices are described in detail. Thermal decoupling of the heater/sensor platforms has been optimized reaching thermal conductances as low as 20 nW K(-1) with a measurements sensitivity below 20 nW K(-1). The InAs NWs were characterized in terms of thermal conductance, four-probe electrical conductance and thermopower (Seebeck coefficient), all measured on a single NW. The temperature dependence of the parameters determining the thermoelectric figure-of-merit of an InAs NW was acquired in the range 200-350 K featuring a minor decrease of the thermal conductivity from 2.7 W (m K)(-1) to 2.3 W (m K)(-1).

MC1R genotype as a predictor of early-onset melanoma, compared with self-reported and physician-measured traditional risk factors: an Australian case-control-family study

Background

Melanocortin-1 receptor (MC1R) gene variants are very common and are associated with melanoma risk, but their contribution to melanoma risk prediction compared with traditional risk factors is unknown. We aimed to 1) evaluate the separate and incremental contribution of MC1R genotype to prediction of early-onset melanoma, and compare this with the contributions of physician-measured and self-reported traditional risk factors, and 2) develop risk prediction models that include MC1R, and externally validate these models using an independent dataset from a genetically similar melanoma population.

Methods

Using data from an Australian population-based, case-control-family study, we included 413 case and 263 control participants with sequenced MC1R genotype, clinical skin examination and detailed questionnaire. We used unconditional logistic regression to estimate predicted probabilities of melanoma. Results were externally validated using data from a similar study in England.

Results

When added to a base multivariate model containing only demographic factors, MC1R genotype improved the area under the receiver operating characteristic curve (AUC) by 6% (from 0.67 to 0.73; P < 0.001) and improved the quartile classification by a net 26% of participants. In a more extensive multivariate model, the factors that contributed significantly to the AUC were MC1R genotype, number of nevi and previous non-melanoma skin cancer; the AUC was 0.78 (95% CI 0.75-0.82) for the model with self-reported nevi and 0.83 (95% CI 0.80-0.86) for the model with physician-counted nevi. Factors that did not further contribute were sun and sunbed exposure and pigmentation characteristics. Adding MC1R to a model containing pigmentation characteristics and other self-reported risk factors increased the AUC by 2.1% (P = 0.01) and improved the quartile classification by a net 10% (95% CI 1-18%, P = 0.03).

Conclusions

Although MC1R genotype is strongly associated with skin and hair phenotype, it was a better predictor of early-onset melanoma than was pigmentation characteristics. Physician-measured nevi and previous non-melanoma skin cancer were also strong predictors. There might be modest benefit to measuring MC1R genotype for risk prediction even if information about traditional self-reported or clinically measured pigmentation characteristics and nevi is already available.

Defect structures in ZnO studied by high-resolution structural and spectroscopic imaging

The formation of characteristic inversion domain structures in zinc oxide (ZnO) is triggered by the addition of trivalent Fe(3+) or In(3+) dopants. As-grown and inverted ZnO domains are separated by two types of inversion domain boundaries (IDBs): basal b-IDBs parallel to {0001}, and pyramidal p-IDBs parallel to {21¯1¯5} lattice planes in three equivalent variants. Cs-corrected analytical TEM/STEM is the method of choice for a comprehensive structural and compositional characterization of these materials. It is shown by electron and X-ray spectroscopic imaging in STEM that dopant species are essentially localized within both types of IDBs, whereas solid solubility of trivalent dopants within ZnO domains is rather low (<0.5at%). Under the assumption of one monolayer per IDB the relation between inversion domain structure and integral dopant concentration correlates well with integral EDS and EELS measurements in STEM over well defined sample regions. The presence of one close-packed monolayer of trivalent dopant ions within a b-IDB is unambiguously confirmed by atomic resolution STEM imaging. Columns of cations are clearly imaged in high-angle annular dark-field (HAADF) STEM imaging, whereas annular bright-field (ABF) STEM is capable of imaging both light and heavy atom columns simultaneously. It is shown that structural details in ABF images are directly interpretable even in specimen regions with thickness >50nm. The structural inversion associated with a stacking fault as a consequence of the presence of octahedrally coordinated In(3+) in the b-IDB is directly revealed by atomic resolution imaging. Column positions in atomic resolution ABF imaging in In2O3-ZnO nanorods show that the oxygen sub-lattice continues across the b-IDB with only marginal distortions, whereas the cation sub-lattice suffers a rigid shift relative to the oxygen lattice as a result of the coordination geometry of ZnO4 tetrahedrons sharing common oxygen ions with the InO6 coordination octahedrons.

Leaching of metal(loid)s from a construction material: influence of the particle size, specific surface area and ionic strength

Construction materials are tested worldwide for a potential release of dangerous substances to prevent adverse effects on humans and biota. It is crucial to identify and understand the processes which are decisive for the release of hazardous substances. The current study compares the results of different test methods. Taking copper slag as model material, the influence of material particle size, eluant composition and ionic strength was tested. Ionic strength and salinity significantly influenced the release of metal(loid)s in the water phase. Furthermore, it was elucidated that colloids can cause methodological artefacts. The available specific surface area exhibited a positive correlation with the release of hazardous substances. The specific surface areas of materials were determined by the Brunauer, Emmett and Teller model (BET) and four other methods. The aluminium foil method showed the best results with regard to the statistical uncertainty, compared to a 3D laser scanning method. With help of the roughness factor λ it is possible to compare the results from surface area measurements with different material particle sizes (0-250 mm). This comparability offers the potential to match the release of metal(loid)s from laboratory studies with field applications and catchment area calculations/modelling, based on the release per m(2).

[Acute kidney injury]

Acute kidney injury plays a pivotal role in intensive care medicine and exerts crucial adverse effects on the course of the disease and overall prognosis of the critically ill patient. Intensive renal support, including initiation of earlier dialysis or maximal uremic toxin removal by higher dosage and frequency of renal replacement therapy, and individualized selection of modality were not able to decrease excessive mortality in this population. Systemic acute inflammation, mediated, at least in part, by cytokines, and not secondary uremic side effects, seems to have a major impact on nonrenal organ damage. Assessment of short-term outcome in critically ill patients who develop acute kidney injury may underestimate the true burden of disease. The overall survival at 5 years in patients discharged alive after severe acute kidney injury necessitating renal replacement therapy is only 20-30%, comparable to cancer patients. In addition, acute renal damage was identified as an independent risk factor for progression of chronic renal insufficiency. Current research focuses on strategies for the prevention of acute kidney injury and on the establishment of effective biomarkers for the early recognition and accurate diagnosis of subclinical renal damage.

MC1R genotypes and risk of melanoma before age 40 years: a population-based case-control-family study

The contribution of melanocortin-1 receptor (MC1R) gene variants to the development of early-onset melanoma is unknown. Using an Australian population-based, case-control-family study, we sequenced MC1R for 565 cases with invasive cutaneous melanoma diagnosed between ages 18 and 39 years, 409 unrelated controls and 518 sibling controls. Variants were classified a priori into "R" variants (D84E, R142H, R151C, I155T, R160W, D294H) and "r" variants (all other nonsynonymous variants). We estimated odds ratios (OR) for melanoma using unconditional (unrelated controls) and conditional (sibling controls) logistic regression. The prevalence of having at least one R or r variant was 86% for cases, 73% for unrelated controls and 81% for sibling controls. R151C conferred the highest risk (per allele OR 2.57, 95% confidence interval 1.86-3.56 for the case-unrelated-control analysis and 1.70 (1.12-2.60) for the case-sibling-control analysis). When mutually adjusted, the ORs per R allele were 2.23 (1.77-2.80) and 2.06 (1.47-2.88), respectively, from the two types of analysis, and the ORs per r allele were 1.69 (1.33-2.13) and 1.25 (0.88-1.79), respectively. The associations were stronger for men and those with none or few nevi or with high childhood sun exposure. Adjustment for phenotype, nevi and sun exposure attenuated the overall log OR for R variants by approximately 18% but had lesser influence on r variant risk estimates. MC1R variants explained about 21% of the familial aggregation of melanoma. Some MC1R variants are important determinants of early-onset melanoma. The strength of association with melanoma differs according to the type and number of variants.