Sentinel lymph node surgery after neoadjuvant chemotherapy in patients with T2 to T4, N0 and N1 breast cancer

BackgroundHistological status of axillary lymph nodes is an important prognostic factor in patients receiving surgery for breast cancer (BC). Sentinel lymph node (SLN) biopsy (B) has rapidly replaced axillary lymph node dissection (ALND), and is now the standard of care for axillary staging in patients with clinically node-negative (N0) operable BC. The aim of this study is to compare pretreatment lymphoscintigraphy with a post primary systemic treatment (PST) scan in order to reduce the false-negative rates for SLNB.MethodsIn this single-institution study we considered 170 consecutive T2-4 N0-1 M0 BC patients treated with anthracycline-based PST. At the time of incisional biopsy, we performed sentinel lymphatic mapping. After PST, all patients repeated lymphoscintigraphy with the same methodology. During definitive surgery we performed further sentinel lymphatic mapping, SLNB and ALND.ResultsThe SLN was removed in 158/170 patients giving an identification rate of 92.9% (95% confidence interval (CI) = 88.0–96.3%) and a false-negative rate of 14.0% (95% CI = 6.3–25.8%). SLNB revealed a sensitivity of 86.0% (95% CI = 74.2–93.7%), an accuracy of 94.9% (95% CI = 90.3–97.8%) and a negative predictive value of 92.7% (95% CI = 86.1–96.8%).ConclusionIdentification rate, sensitivity and accuracy are in accordance with other studies on SLNB after PST, even after clinically negative node conversion following PST. This study confirms that diagnostic biopsy and neoadjuvant chemotherapy maintain breast lymphatic drainage unaltered.     

Multi-tissue DNA methylation age: Molecular relationships and perspectives for advancing biomarker utility

The multi-tissue DNA methylation estimator of chronological age (DNAm-age) has been associated with a wide range of exposures and health outcomes. Still, it is unclear how DNAm-age can have such broad relationships and how it can be best utilized as a biomarker. Understanding DNAm-age’s molecular relationships is a promising approach to address this critical knowledge gap. In this review, we discuss the existing literature regarding DNAm-age’s molecular relationships in six major categories: animal model systems, cancer processes, cellular aging processes, immune system processes, metabolic processes, and nucleic acid processes. We also present perspectives regarding the future of DNAm-age research, including the need to translate a greater number of ongoing research efforts to experimental and animal model systems.     

Utilising allelic dropout probabilities estimated by logistic regression in casework

Some advanced methods for DNA profile interpretation require a probability for the event of dropout. Methods have been suggested based on logistic regression. Two of these respectively use a proxy for template that is constant across loci and one that is modelled using an exponential curve. Both of these methods allow different modelling constants from each locus. A variant of the model using an exponential curve is discussed. This variant constrains the constants to be the same for every locus. We test these two methods and the variant by developing the constants (training) on one set of data and testing them on another. This mimics the likely use in casework. We find that the new variant appears to be the most useful in that it performs better than the other two options when trained on one data set and used on another. The hypothesised reason for this is that locus to locus variation in amplification efficiency varies with time, multimix batch, or from sample to sample.     

Socioeconomic status and event free survival in pediatric acute lymphoblastic leukemia: A population-based cohort study

The impact of socioeconomic status (SES) upon childhood cancer outcomes has not been extensively examined. Our objective was to determine the association between SES and event-free survival (EFS) among children with acute lymphoblastic leukemia (ALL) diagnosed in Ontario, Canada from 1995–2011 (N = 1541) using Cox proportional hazards. Neither neighborhood-level median income quintile, distance from tertiary center, or rural residence significantly predicted EFS in the context of a universal healthcare system. Immigrant children experienced significantly superior EFS; confounding by ethnicity could not be ruled out. Confirmatory studies using additional individual-level SES variables are warranted.     

Local ancestry at APOE modifies Alzheimer's disease risk in Caribbean Hispanics

IntroductionAlthough the relationship between APOE and Alzheimer's disease (AD) is well established in populations of European descent, the effects of APOE and ancestry on AD risk in diverse populations is not well understood.MethodsLogistic mixed model regression and survival analyses were performed in a sample of 3067 Caribbean Hispanics and 3028 individuals of European descent to assess the effects of APOE genotype, local ancestry, and genome-wide ancestry on AD risk and age at onset.ResultsAmong the Caribbean Hispanics, individuals with African-derived ancestry at APOE had 39% lower odds of AD than individuals with European-derived APOE, after adjusting for APOE genotype, age, and genome-wide ancestry. While APOE E2 and E4 effects on AD risk and age at onset were significant in the Caribbean Hispanics, they were substantially attenuated compared with those in European ancestry individuals.DiscussionThese results suggest that additional genetic variation in the APOE region influences AD risk beyond APOE E2/E3/E4.