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Background: Cancer epidemiology studies require sufficient power to assess spatial relationships between exposures and cancer incidence accurately. However, methods for power calculations of spatial statistics are complicated and underdeveloped, and therefore underutilized by investigators. The spatial relative risk function, a cluster detection technique that detects spatial clusters of point-level data for two groups (e.g., cancer cases and controls, two exposure groups), is a commonly used spatial statistic but does not have a readily available power calculation for study design., Results: We developed sparrpowR as an open-source R package to estimate the statistical power of the spatial relative risk function. sparrpowR generates simulated data applying user-defined parameters (e.g., sample size, locations) to detect spatial clusters with high statistical power. We present applications of sparrpowR that perform a power calculation for a study designed to detect a spatial cluster of incident cancer in relation to a point source of numerous environmental emissions. The conducted power calculations demonstrate the functionality and utility of sparrpowR to calculate the local power for spatial cluster detection., Conclusions: sparrpowR improves the current capacity of investigators to calculate the statistical power of spatial clusters, which assists in designing more efficient studies. This newly developed R package addresses a critically underdeveloped gap in cancer epidemiology by estimating statistical power for a common spatial cluster detection technique.

Telomeres are DNA-protein structures at the ends of chromosomes essential in maintaining chromosomal stability. Observational studies have identified associations between telomeres and elevated cancer risk, including hematologic malignancies; but biologic mechanisms relating telomere length to cancer etiology remain unclear. Our study sought to better understand the relationship between telomere length and cancer risk by evaluating genetically-predicted telomere length (gTL) in relation to the presence of clonal somatic copy number alterations (SCNAs) in peripheral blood leukocytes. Genotyping array data were acquired from 431,507 participants in the UK Biobank and used to detect SCNAs from intensity information and infer telomere length using a polygenic risk score (PRS) of variants previously associated with leukocyte telomere length. In total, 15,236 (3.5%) of individuals had a detectable clonal SCNA on an autosomal chromosome. Overall, higher gTL value was positively associated with the presence of an autosomal SCNA (OR = 1.07, 95% CI = 1.05-1.09, P = 1.61×10-15). There was high consistency in effect estimates across strata of chromosomal event location (e.g., telomeric ends, interstitial or whole chromosome event; Phet = 0.37) and strata of copy number state (e.g., gain, loss, or neutral events; Phet = 0.05). Higher gTL value was associated with a greater cellular fraction of clones carrying autosomal SCNAs (β = 0.004, 95% CI = 0.002-0.007, P = 6.61×10-4). Our population-based examination of gTL and SCNAs suggests inherited components of telomere length do not preferentially impact autosomal SCNA event location or copy number status, but rather likely influence cellular replicative potential., Competing Interests: The authors declare no competing interests.

Genome-wide association studies (GWAS) have identified thousands of germline susceptibility loci associated with risk for cancer as well as a wide range of other traits and diseases. An interest of many investigators is identifying traits or diseases that share common susceptibility loci. We developed LDtrait (https://ldlink.nci.nih.gov/?tab=ldtrait) as an open access web tool for finding germline variation associated with multiple traits. LDtrait searches the NHGRI-EBI GWAS Catalog to identify susceptibility loci in linkage disequilibrium (LD) with a user-provided list of query variants. Options allow for modifying LD thresholds, calculating LD from a diverse set of reference populations, and downloading annotated variant lists. Results from example query searches highlight the utility of LDtrait in uncovering cross-trait associations for cancer risk and other traits. LDtrait accelerates etiologic understanding of cancer genetics by rapidly identifying genetic similarities with other traits or diseases. SIGNIFICANCE: The new GWAS search tool LDtrait will expedite discovery of shared genetic components underlying seemingly unrelated diseases and may offer novel insights into cancer research., (©2020 American Association for Cancer Research.)

Purpose: To investigate a new clinical role for medical physicists in direct patient care with a prospective phase 2 clinical trial., Materials and Methods: Medical physicists participated in the Physics Direct Patient Care (PDPC) protocol, establishing independent professional relationships with radiation oncology patients. After attending a dedicated patient communication training program, medical physicists routinely met with patients for 2 physicist-patient consults to explain the treatment planning and delivery process, review the patient's treatment plan, and answer all technical questions. The first physicist-patient consult took place immediately before the computed tomography simulation, and the second took place immediately before the first treatment. Questionnaires were administered to each patient on the PDPC protocol at 3 time points to assess both anxiety and satisfaction. The first questionnaire was given shortly after the first physicist-patient consult, the second questionnaire was given shortly after the second physicist-patient consult, and the third questionnaire was given after the last treatment appointment, with no associated physicist-patient consult., Results: The mean patient anxiety score was considered to be low at all questionnaire time points. There was a statistically significant decrease (P < .0001) in anxiety from the simulation time point to the first treatment time point. The mean patient technical satisfaction score was considered to be high at all measurement time points. There was a statistically significant increase (P = .0012) in technical satisfaction from the simulation time point to the first treatment time point. There was a statistically significant decrease (P < .023) in technical satisfaction from the first treatment time point to the last treatment time point., Conclusions: Establishing a new clinical role for medical physicists and investigating its effects on patient anxiety and satisfaction have created the foundation for future studies. Based on the results of this trial, the PDPC protocol will be expanded to a larger group of medical physicists, radiation oncologists, and patient disease sites and investigated with a randomized phase 3 clinical trial., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Objectives: To develop a training program designed to meet the specific needs of medical physicists as they transition into a clinical role with direct patient care responsibilities., Materials and Methods: The training program was designed in collaboration with the faculty at the UC San Diego School of Medicine and incorporates training techniques that have been shown to be effective in improving communication skills. The program emphasizes experiential, practice-based learning over didactic presentations., Results: The training program is comprised of 5 components: 1) a 1-day Clinician-Patient Communication Workshop run by the UC San Diego School of Medicine, 2) Communication Strategies for Radiation Oncology, which consists of two, 2-hour sessions designed to provide trainees with patient communication skills that are specific to patient interactions in radiation oncology, 3) Simulated Patient Interactions, in which trainees perform mock physicist-patient consults with trained patient actors, 4) Faculty-Observed Patient Consults, and 5) a Case-Based Treatment Toxicity Course. A competency assessment mechanism was also developed to provide a clear set of objectives and to guide trainer feedback. [Correction added after first online publication on November 7, 2018: The phrase ", which consists of two, 2-hour" was added above.] CONCLUSIONS: The training program that we have developed incorporates an array of established education techniques and provides a comprehensive, accessible, means of improving medical physicists' patient communication skills., (© 2018 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.)

The international growth of cancer and lack of available treatment is en route to become a global crisis. With >60% of cancer patients needing radiation therapy at some point during their treatment course, the lack of available facilities and treatment programs worldwide is extremely problematic. The number of deaths from treatable cancers is projected to increase to 11.5 million deaths in 2030 because the international population is aging and growing. In this review, we present how best to answer the need for radiation therapy facilities from a technical standpoint. Specifically, we examine whether cobalt teletherapy machines or megavoltage linear accelerator machines are best equipped to handle the multitudes in need of radiation therapy treatment in the developing world., (Copyright © 2014 Elsevier Inc. All rights reserved.)