Experimental validation of a novel method of dose accumulation for the rectum

BACKGROUND

Dose-surface maps (DSMs) are an increasingly popular tool to evaluate spatial dose-outcome relationships for the rectum. Recently, DSM addition has been proposed as an alternative method of dose accumulation from deformable registration-based techniques. In this study, we performed the first experimental investigation of the accuracy at which DSM accumulation can capture the total dose delivered to a rectum's surface in the presence of inter-fraction motion.

MATERIAL AND METHODS

A custom PVC rectum phantom capable of representing typical rectum inter-fraction motion and filling variations was constructed for this project. The phantom allowed for the placement of EBT3 film sheets on the representative rectum surface to measure rectum surface dose. A multi-fraction prostate VMAT treatment was designed and delivered to the phantom in a water tank for a variety of inter-fraction motion scenarios. DSMs for each fraction were calculated in two ways using CBCT images acquired during delivery and summed to produce accumulated DSMs. Accumulated DSMs were then compared to film measurements using gamma analysis (3%/2 mm criteria). Similarity of isodose clusters between films and DSMs was also investigated.

RESULTS

Baseline agreement between film measurements and accumulated DSMs for a stationary rectum was 95.6%. Agreement between film and accumulated DSMs in the presence of different types of inter.-fraction motion was ≥92%, and isodose cluster mean distance to agreement was within 1.5 mm for most scenarios. Overall, DSM accumulation performed the best when using DSMs that accounted for changes in rectum path orientation.

CONCLUSION

Dose accumulation performed with DSMs was found to accurately replicate total delivered dose to a rectum phantom in the presence of inter-fraction motion.

Pan-Asian adapted ESMO Clinical Practice Guidelines for the diagnosis, treatment and follow-up of patients with prostate cancer

The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of prostate cancer was published in 2020. It was therefore decided, by both the ESMO and the Singapore Society of Oncology (SSO), to convene a special, virtual guidelines meeting in November 2021 to adapt the ESMO 2020 guidelines to take into account the differences associated with the treatment of prostate cancer in Asia. These guidelines represent the consensus opinions reached by experts in the treatment of patients with prostate cancer representing the oncological societies of China (CSCO), India (ISMPO), Japan (JSMO), Korea (KSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence and was independent of the current treatment practices and drug access restrictions in the different Asian countries. The latter were discussed when appropriate. The aim is to provide guidance for the optimisation and harmonisation of the management of patients with prostate cancer across the different regions of Asia.

Pan-Asian adapted ESMO Clinical Practice Guidelines for the diagnosis, treatment and follow-up of patients with renal cell carcinoma

The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of renal cell carcinoma was published in 2019 with an update planned for 2021. It was therefore decided by both the ESMO and the Singapore Society of Oncology (SSO) to convene a special, virtual guidelines meeting in May 2021 to adapt the ESMO 2019 guidelines to take into account the ethnic differences associated with the treatment of renal cell carcinomas in Asian patients. These guidelines represent the consensus opinions reached by experts in the treatment of patients with renal cell carcinoma representing the oncological societies of China (CSCO), India (ISMPO), Japan (JSMO), Korea (KSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence and was independent of the current treatment practices and drug access restrictions in the different Asian countries. The latter were discussed when appropriate.

A systematic review of autologous adipose-derived stromal vascular fraction (SVF) for the treatment of acute cutaneous wounds

BACKGROUND

Stromal vascular fraction (SVF), derived enzymatically or mechanically from adipose tissue, contains a heterogenous population of cells and stroma, including multipotent stem cells. The regenerative capacity of SVF may potentially be adapted for a broad range of clinical applications, including the healing of acute cutaneous wounds.

OBJECTIVE

To evaluate the available literature on the efficacy and safety of autologous adipose-derived stromal vascular fraction (SVF) for the treatment of acute cutaneous wounds in humans.

METHODS

A systematic review of the literature utilizing MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials was performed to identify published clinical trials of autologous adipose-derived SVF or similar ADSC-containing derivatives for patients with acute cutaneous wounds. This was supplemented by searches for ongoing clinical trials through ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform.

RESULTS

872 records were initially retrieved. Application of inclusion and exclusion criteria yielded 10 relevant studies: two completed non-randomized controlled trials and eight ongoing clinical trials. Both completed studies reported a statistically significant benefit in percentage re-epithelialization and time to healing for the SVF treatment arms. Safety information for SVF was not provided. Ongoing clinical trials were assessing outcomes such as safety, patient and observer reported scar appearance, wound healing rate, and wound epithelization.

CONCLUSION

In the context of substantial limitations in the quantity and quality of available evidence, the existing literature suggests that SVF may be a useful treatment for acute cutaneous wounds in humans. More clinical trials with improved outcome measures and safety assessment are needed.

Development of a core outcome set for cutaneous squamous cell carcinoma trials: identification of core domains and outcomes

BACKGROUND

The lack of uniformity in the outcomes reported in clinical studies of the treatment of cutaneous squamous cell carcinoma (cSCC) complicates efforts to compare treatment effectiveness across trials.

OBJECTIVES

To develop a core outcome set (COS), a minimum set of agreed-upon outcomes to be measured in all clinical trials of a given disease or outcome, for the treatment of cSCC.

METHODS

One hundred and nine outcomes were identified via a systematic literature review and interviews with 28 stakeholders. After consolidation of this long list, 55 candidate outcomes were rated by 19 physician and 10 patient stakeholders, in two rounds of Delphi exercises. Outcomes scored 'critically important' (score of 7, 8 or 9) by ≥ 70% of patients and ≥ 70% of physicians were provisionally included. At the consensus meeting, after discussion and voting of 44 international experts and patients, the provisional list was reduced to a final core set, for which consensus was achieved among all meeting participants.

RESULTS

A core set of seven outcomes was finalized at the consensus meeting: (i) serious or persistent adverse events, (ii) patient-reported quality of life, (iii) complete response, (iv) partial response, (v) recurrence-free survival, (vi) progression-free survival and (vii) disease-specific survival.

CONCLUSIONS

In order to increase the comparability of results across trials and to reduce selective reporting bias, cSCC researchers should consider reporting these core outcomes. Further work needs to be performed to identify the measures that should be reported for each of these outcomes.

Novel therapeutic strategies targeting telomere maintenance mechanisms in high-risk neuroblastoma

The majority of high-risk neuroblastomas can be divided into three distinct molecular subgroups defined by the presence of MYCN amplification, upstream TERT rearrangements or alternative lengthening of telomeres (ALT). The common defining feature of all three subgroups is altered telomere maintenance; MYCN amplification and upstream TERT rearrangements drive high levels of telomerase expression whereas ALT is a telomerase independent telomere maintenance mechanism. As all three telomere maintenance mechanisms are independently associated with poor outcomes, the development of strategies to selectively target either telomerase expressing or ALT cells holds great promise as a therapeutic approach that is applicable to the majority of children with aggressive disease.Here we summarise the biology of telomere maintenance and the molecular drivers of aggressive neuroblastoma before describing the most promising therapeutic strategies to target both telomerase expressing and ALT cancers. For telomerase-expressing neuroblastoma the most promising targeted agent to date is 6-thio-2'-deoxyguanosine, however clinical development of this agent is required. In osteosarcoma cell lines with ALT, selective sensitivity to ATR inhibition has been reported. However, we present data showing that in fact ALT neuroblastoma cells are more resistant to the clinical ATR inhibitor AZD6738 compared to other neuroblastoma subtypes. More recently a number of additional candidate compounds have been shown to show selectivity for ALT cancers, such as Tetra-Pt (bpy), a compound targeting the telomeric G-quadruplex and pifithrin-α, a putative p53 inhibitor. Further pre-clinical evaluation of these compounds in neuroblastoma models is warranted.In summary, telomere maintenance targeting strategies offer a significant opportunity to develop effective new therapies, applicable to a large proportion of children with high-risk neuroblastoma. In parallel to clinical development, more pre-clinical research specifically for neuroblastoma is urgently needed, if we are to improve survival for this common poor outcome tumour of childhood.

An Analysis of the Psychosocial, Financial and Emotional Needs of Adolescent and Young Adult Cancer Survivors in Singapore Through Focus Group Discussions

Background: The adolescent and young adult (AYA) population, aged between 15-39 years, is an understudied and medically underserved community of cancer survivors in Singapore. Aim: This study was designed to elicit perspectives on various psychosocial, emotional and financial concerns that the AYA cancer survivors (CS) encountered, in their transition to survivorship. Methods: The AYA CS in the age range of 18-39 years, with at least 6 months to 2 years since diagnosis and/or completion of curative treatment were recruited for this study. Four focus group discussions, which consisted of 2-4 respondents, were conducted within the premises of National Cancer Centre Singapore. Participants were prompted by the facilitator with a series of open-ended questions on themes specific to survivorship, including treatment side-effects, sexual and reproductive health concerns, changes in work or education and survivorship support services. Participants' responses were then transcribed verbatim, and analyzed through qualitative content analysis. Results: Twelve AYA, with a mean (±SD) age of 27.1 (±5.9) years, participated in four focus group discussions. The mean (±SD) number of years since cancer diagnosis was 2.3 (±0.6) years, with majority diagnosed with non-Hodgkin's lymphoma (41.6%) and germ cell tumor (25.0%). AYA CS were greatly affected by physical side-effects such as alopecia, changes in body image, and cognitive changes. There were also emotional concerns including the fear of recurrence, infertility anxieties, poor insurance coverage and lack of career advancement opportunities. Majority expressed that they preferred consulting a specialist rather than a general practitioner for their follow-up care. Conclusion: The AYA CS suffer from a multitude of problems as they transit toward survivorship. Innovative and effective survivorship care models are required to timely address their bio-psychosocial, financial and emotional concerns.

Video education to improve recognition of common benign and malignant cutaneous lesions and skin cancer prevention in the public

OBJECTIVE

Although dermatologists strive to provide patient education on sun protection and skin cancer, approximately 90% of Americans have limited health literacy skills. Little has been written about the means to best teach all levels of learners to recognize common benign and malignant skin lesions. Earlier work found that with advancing age, adults were less able to identify concerning lesions, thus underscoring the need for accessible education.

METHODS

We showed subjects a brief video (7th grade level) about common cutaneous growths, reducing the risk of skin cancer, and the importance of early detection. Subjects were asked about their skin cancer history, educational format preference, and the perceived impact of the video. Comprehension of symptoms of skin cancer and the benefits of sunscreen use and the ability to identify a melanoma, nevus, angioma, and seborrheic keratosis were also assessed.

RESULTS

Of the 156 subjects, mean age 52.7 years (range, 18-88 years), 31% had a history of skin cancer. A total of 98.7% found the video to be helpful; 92% preferred having a video as part of their teaching versus 9% who preferred written materials alone, 99% knew that a new or changing lesion could signal skin cancer, and 100% correctly answered that wearing sunscreen is protective. Subjects correctly identified lesions as melanoma (99%), benign mole (97%), angiomas (96%), and seborrheic keratosis (91%). There was a nominal trend toward higher scores in people who preferred video learning, had no history of skin cancer, and were older than 60 years of age.

CONCLUSION

In this study, we found that a brief, plain-language video was effective at conveying understandable content to help subjects learn to identify common cancerous and benign skin growths while also teaching them strategies to protect against skin cancer.

Translation of the Diabetes Prevention Program for diabetes risk reduction in Chinese immigrants in New York City

AIMS

To evaluate the effectiveness and feasibility of implementing a linguistically and culturally tailored Diabetes Prevention Program among Chinese immigrants with prediabetes living in New York City.

METHODS

A total of 60 Chinese immigrants with prediabetes were randomized into either a Diabetes Prevention Program lifestyle intervention (n = 30) consisting of 12 bi-weekly core sessions and six monthly post-core sessions or the control intervention (n = 30), consisting of quarterly mailing of diabetes prevention information. Each Diabetes Prevention Program intervention session lasted 1.5-2 h and covered topics such as healthy eating, physical activity, stress reduction and problem-solving skills. Outcomes such as percent change in weight, BMI, and HbA1c concentration were assessed at baseline, 6 and 12 months. A mixed-effects linear regression was applied to test the intervention effect at months 6 and 12. Data were collected in the period 2012-2013 and analysed in 2014.

RESULTS

The participant attrition rate was < 5% (2 out of 60) at 12 months. There was a significantly greater percent weight loss in the intervention group (-3.5 vs. -0.1%; P = 0.0001) at 6 months, which was largely maintained at 12 months (-3.3 vs. 0.3%; P = 0.0003).

CONCLUSIONS

Participants in a Diabetes Prevention Program-based intervention achieved greater weight loss and improvements in HbA1c concentration than control participants. Evaluation of the Chinese Diabetes Prevention Program curriculum in a larger trial is warranted.

Nitric Oxide-cGMP-PKG Pathway Acts on Orai1 to Inhibit the Hypertrophy of Human Embryonic Stem Cell-Derived Cardiomyocytes

Cardiac hypertrophy is an abnormal enlargement of heart muscle. It frequently results in congestive heart failure, which is a leading cause of human death. Previous studies demonstrated that the nitric oxide (NO), cyclic GMP (cGMP), and protein kinase G (PKG) signaling pathway can inhibit cardiac hypertrophy and thus improve cardiac function. However, the underlying mechanisms are not fully understood. Here, based on the human embryonic stem cell-derived cardiomyocyte (hESC-CM) model system, we showed that Orai1, the pore-forming subunit of store-operated Ca(2+) entry (SOCE), is the downstream effector of PKG. Treatment of hESC-CMs with an α-adrenoceptor agonist phenylephrine (PE) caused a marked hypertrophy, which was accompanied by an upregulation of Orai1. Moreover, suppression of Orai1 expression/activity using Orai1-siRNAs or a dominant-negative construct Orai1(G98A) inhibited the hypertrophy, suggesting that Orai1-mediated SOCE is indispensable for the PE-induced hypertrophy of hESC-CMs. In addition, the hypertrophy was inhibited by NO and cGMP via activating PKG. Importantly, substitution of Ala for Ser(34) in Orai1 abolished the antihypertrophic effects of NO, cGMP, and PKG. Furthermore, PKG could directly phosphorylate Orai1 at Ser(34) and thus prevent Orai1-mediated SOCE. Together, we conclude that NO, cGMP, and PKG inhibit the hypertrophy of hESC-CMs via PKG-mediated phosphorylation on Orai1-Ser-34. These results provide novel mechanistic insights into the action of cGMP-PKG-related antihypertrophic agents, such as NO donors and sildenafil.

Emergency medicine resident physicians' perceptions of electronic documentation and workflow: a mixed methods study

OBJECTIVE

To understand emergency department (ED) physicians' use of electronic documentation in order to identify usability and workflow considerations for the design of future ED information system (EDIS) physician documentation modules.

METHODS

We invited emergency medicine resident physicians to participate in a mixed methods study using task analysis and qualitative interviews. Participants completed a simulated, standardized patient encounter in a medical simulation center while documenting in the test environment of a currently used EDIS. We recorded the time on task, type and sequence of tasks performed by the participants (including tasks performed in parallel). We then conducted semi-structured interviews with each participant. We analyzed these qualitative data using the constant comparative method to generate themes.

RESULTS

Eight resident physicians participated. The simulation session averaged 17 minutes and participants spent 11 minutes on average on tasks that included electronic documentation. Participants performed tasks in parallel, such as history taking and electronic documentation. Five of the 8 participants performed a similar workflow sequence during the first part of the session while the remaining three used different workflows. Three themes characterize electronic documentation: (1) physicians report that location and timing of documentation varies based on patient acuity and workload, (2) physicians report a need for features that support improved efficiency; and (3) physicians like viewing available patient data but struggle with integration of the EDIS with other information sources.

CONCLUSION

We confirmed that physicians spend much of their time on documentation (65%) during an ED patient visit. Further, we found that resident physicians did not all use the same workflow and approach even when presented with an identical standardized patient scenario. Future EHR design should consider these varied workflows while trying to optimize efficiency, such as improving integration of clinical data. These findings should be tested quantitatively in a larger, representative study.