A Visual Aid Tool for Detection of Pancreatic Tumour-Vessel Contact on Staging CT: A Retrospective Cohort Study

Purpose: In pancreatic adenocarcinoma, the difficult distinction between normal and affected pancreas on CT studies may lead to discordance between the pre-surgical assessment of vessel involvement and intraoperative findings. We hypothesize that a visual aid tool could improve the performance of radiology residents when detecting vascular invasion in pancreatic adenocarcinoma patients. Methods: This study consisted of 94 pancreatic adenocarcinoma patient CTs. The visual aid compared the estimated body fat density of each patient with the densities surrounding the superior mesenteric artery and mapped them onto the CT scan. Four radiology residents annotated the locations of perceived vascular invasion on each scan with the visual aid overlaid on alternating scans. Using 3 expert radiologists as the reference standard, we quantified the area under the receiver operating characteristic curve to determine the performance of the tool. We then used sensitivity, specificity, balanced accuracy ((sensitivity + specificity)/2), and spatial metrics to determine the performance of the residents with and without the tool. Results: The mean area under the curve was 0.80. Radiology residents' sensitivity/specificity/balanced accuracy for predicting vascular invasion were 50%/85%/68% without the tool and 81%/79%/80% with it compared to expert radiologists, and 58%/85%/72% without the tool and 78%/77%/77% with it compared to the surgical pathology. The tool was not found to impact the spatial metrics calculated on the resident annotations of vascular invasion. Conclusion: The improvements provided by the visual aid were predominantly reflected by increased sensitivity and accuracy, indicating the potential of this tool as a learning aid for trainees.

Magnetic Resonance Imaging-Targeted Versus Systematic Prostate Biopsies: 2-year Follow-up of a Prospective Randomized Trial (PRECISE)

BACKGROUND

The prospective randomized PRECISE trial demonstrated that magnetic resonance imaging (MRI) with only targeted biopsy (TBx) was noninferior to systematic transrectal ultrasound biopsy (SBx) in the detection of International Society of Urological Pathology grade group (GG) ≥2 prostate cancer (PC). An unanswered question is the outcome for patients who avoided a biopsy because of negative MRI findings.

OBJECTIVE

To explore the rate of PC diagnosis based on 2-yr MRI for PRECISE participants who had no biopsy and for patients who had a negative result or GG 1 on TBx in comparison to those with a negative result or GG 1 on SBx.

DESIGN, SETTING, AND PARTICIPANTS

The PRECISE prospective trial was conducted at five Canadian academic centers. The present analysis was for trial participants who were not diagnosed with clinically significant PC (csPC) at baseline. Of 453 randomized patients, 146 were diagnosed with GG ≥2 at baseline and were excluded. Eligible patients for this study included 83 men from the MRI arm who had negative MRI findings and no biopsy, 120 from the overall cohort who had a negative SBx or TBx, and 72 from the overall cohort who were diagnosed with GG 1 disease.

INTERVENTION

MRI at 2 yr in all men in the MRI and SBx arms and TBx for lesions with a Prostate Imaging-Reporting and Data System score of ≥3 or on the basis of clinical suspicion.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary outcome was the proportion of men diagnosed with GG ≥2 cancer. Secondary outcomes included the MRI outcome and the proportion of men diagnosed with GG 1 PC.

RESULTS AND LIMITATIONS

Evaluable 2-yr MRI scans were available for 75 (56%) eligible patients in the MRI arm and 69 (49%) in the SBx arm. Of these patients, 55 (73%) in the MRI arm and 51 (67%) SBx arm had negative 2-yr MRI. Of the 76 patients in the SBx arm with 2-yr MRI, 16 (21%) had a biopsy, for which the result was negative in eight (10%), GG1 in two (2.6%), and GG ≥2 in six (7.9%) cases. Of the 75 men in the MRI arm with 2-yr MRI, eight (11%) were biopsied, for which the result was negative in four cases (5%) and GG ≥2 in the other four (5%). At 2 yr, including baseline biopsy results, 116/221 (52.5%) in the MRI arm and 113/204 (55%) in the SBx arm were free of GG ≥2 disease, treatment, death from any cause, or progression (OR 1.08; p = 0.66).

CONCLUSIONS

After 2-yr follow-up including MRI for patients in both arms of PRECISE, there was no difference in the rate of csPC diagnosis between the MRI and SBx groups, even though 38% of men in the MRI group avoided an initial biopsy.

PATIENT SUMMARY

The PRECISE trial compared systematic biopsy of the prostate to a strategy of magnetic resonance imaging (MRI) with targeted biopsy of any lesions suspicious for cancer on the scan. After 2 years of follow-up that included 2-year MRI with or without biopsy in both groups, there was no difference in the rate of diagnosis of significant cancer, even though 38% of men in the initial MRI arm avoided an initial biopsy, and 30% avoided biopsy altogether. The PRECISE trial is registered on ClinicalTrials.gov as NCT02936258.

Rectal cancer lexicon 2023 revised and updated consensus statement from the Society of Abdominal Radiology Colorectal and Anal Cancer Disease-Focused Panel

The Society of Abdominal Radiology's Colorectal and Anal Cancer Disease-Focused Panel (DFP) first published a rectal cancer lexicon paper in 2019. Since that time, the DFP has published revised initial staging and restaging reporting templates, and a new SAR user guide to accompany the rectal MRI synoptic report (primary staging). This lexicon update summarizes interval developments, while conforming to the original lexicon 2019 format. Emphasis is placed on primary staging, treatment response, anatomic terminology, nodal staging, and the utility of specific sequences in the MRI protocol. A discussion of primary tumor staging reviews updates on tumor morphology and its clinical significance, T1 and T3 subclassifications and their clinical implications, T4a and T4b imaging findings/definitions, terminology updates on the use of MRF over CRM, and the conundrum of the external sphincter. A parallel section on treatment response reviews the clinical significance of near-complete response and introduces the lexicon of "regrowth" versus "recurrence". A review of relevant anatomy incorporates updated definitions and expert consensus of anatomic landmarks, including the NCCN's new definition of rectal upper margin and sigmoid take-off. A detailed review of nodal staging is also included, with attention to tumor location relative to the dentate line and locoregional lymph node designation, a new suggested size threshold for lateral lymph nodes and their indications for use, and imaging criteria used to differentiate tumor deposits from lymph nodes. Finally, new treatment terminologies such as organ preservation, TNT, TAMIS and watch-and-wait management are introduced. This 2023 version aims to serve as a concise set of up-to-date recommendations for radiologists, and discusses terminology, classification systems, MRI and clinical staging, and the evolving concepts in diagnosis and treatment of rectal cancer.

Imaging of colon and rectal cancer

Colon and rectal cancer imaging has traditionally been performed to assess for distant disease (typically lung and liver metastases) and to assess the resectability of the primary tumor. With technological and scientific advances in imaging and the evolution of treatment options, the role of imaging has expanded. Radiologists are now expected to provide a precise description of primary tumor invasion extent, including adjacent organ invasion, involvement of the surgical resection plane, extramural vascular invasion, lymphadenopathy, and response to neoadjuvant treatment, and to monitor for recurrence after clinical complete response.

SAR user guide to the rectal MR synoptic report (primary staging)

Rectal MR is the key diagnostic exam at initial presentation for rectal cancer patients. It is the primary determinant in establishing clinical stage for the patient and greatly impacts the clinical decision-making process. Consequently, structured reporting for MR is critically important to ensure that all required information is provided to the clinical care team. The SAR initial staging reporting template has been constructed to address these important items, including locoregional extent and factors impacting the surgical approach and management of the patient. Potential outputs to each item are defined, requiring the radiologist to commit to a result. This provides essential information to the surgeon or oncologist to make specific treatment deisions for the patient. The SAR Initial Staging MR reporting template has now been officially adopted by the NAPRC (National Accreditation Program for Rectal Cancer) under the American College of Surgery. With the recent revisions to the reporting template, this user guide has been revamped to improve its practicality and support to the radiologist to complete the structured report. Each line item of the report is supplemented with clinical perspectives, images, and illustrations to help the radiologist understand the potential implications for a given finding. Common errors and pitfalls to avoid are highlighted. Ideally, rectal MR interpretation should not occur in a vacuum but in the context of a multi-disciplinary tumor board to ensure that healthcare providers use common terminology and share a solid understanding of the strengths and weaknesses of MR.

Can We Identify Predictors of Success in Contouring Education for Radiation Oncology Trainees? An Analysis of the Anatomy and Radiology Contouring Bootcamp: Predictors of Success in Contouring Education

INTRODUCTION

Although several different contouring instructional programs are available to radiation oncologists and trainees, very little is known about which methods and resources benefit learners most, and whether some learners may need alternate forms of instruction. This study aimed to determine the factors that were predictors of learners' success in anatomy, radiology, and contouring education.

METHODS

Participants in the online and face-to-face (F2F) Anatomy and Radiology Contouring (ARC) Bootcamp completed pre- and post-intervention evaluations that assessed anatomy/radiology knowledge, contouring skills, self-confidence, and spatial ability. Baseline factors were assessed as predictors of outcomes across multiple educational domains.

RESULTS

One hundred and eighty (F2F: n=40; online: n=140) participants enrolled in the ARC Bootcamp and fifty-seven (F2F: n=30; online: n=27) participants completed both evaluations. Of the participants enrolled, 37% were female, and most were radiation oncology (RO) residents (62%). In the anatomy/radiology knowledge testing, all quartiles (based on baseline performance) improved numerically, however, the largest improvements occurred in learners with the lowest baseline scores (p<0.001). At the end of the Bootcamp, learners with lower-performing scores did not reach the level of learners with the highest baseline scores (Bonferroni-corrected p<0.001). Regarding the contouring assessment, improvements were only evident for the participants with lower-performing baseline scores (p<0.05). Spatial anatomy skills, as measured by the spatial anatomy task, was correlated to contouring ability. Overall, the greatest improvements were seen for learners in postgraduate year 1-3, those with no previous rotation experience in a given discipline, and those who attended from 'other' programs (i.e. medical physics residents and medical students).

CONCLUSIONS

The ARC Bootcamp improved all levels of performers' anatomy and radiology knowledge but only lower-performers' contouring ability. The course alone does not help lower-performing learners reach the abilities of higher-performers. The ARC Bootcamp tends to be most beneficial for participants with less RO experience. Curriculum modifications can be made to help support ARC Bootcamp participants with lower performing scores.

Imaging Biomarkers in Prostate Stereotactic Body Radiotherapy: A Review and Clinical Trial Protocol

Advances in imaging have changed prostate radiotherapy through improved biochemical control from focal boost and improved detection of recurrence. These advances are reviewed in the context of prostate stereotactic body radiation therapy (SBRT) and the ARGOS/CLIMBER trial protocol. ARGOS/CLIMBER will evaluate 1) the safety and feasibility of SBRT with focal boost guided by multiparametric MRI (mpMRI) and ¹⁸F-PSMA-1007 PET and 2) imaging and laboratory biomarkers for response to SBRT. To date, response to prostate SBRT is most commonly evaluated using the Phoenix Criteria for biochemical failure. The drawbacks of this approach include lack of lesion identification, a high false-positive rate, and delay in identifying treatment failure. Patients in ARGOS/CLIMBER will receive dynamic ¹⁸F-PSMA-1007 PET and mpMRI prior to SBRT for treatment planning and at 6 and 24 months after SBRT to assess response. Imaging findings will be correlated with prostate-specific antigen (PSA) and biopsy results, with the goal of early, non-invasive, and accurate identification of treatment failure.

Radiation Oncology Fellowship: a Value-Based Assessment Among Graduates of a Mature Program

The University of Toronto - Department of Radiation Oncology (UTDRO) has had a well-established Fellowship Program for over 20 years. An assessment of its graduates was conducted to evaluate training experience and perceived impact on professional development. Graduates of the UTDRO Fellowship Program between 1991 and 2015 were the focus of our review. Current employment status was collected using online tools. A study-specific web-based questionnaire was distributed to 263/293 graduates for whom active e-mails were identified; questions focused on training experience, and impact on career progression and academic productivity. As a surrogate measure for the impact of UTDRO Fellowship training, a comparison of current employment and scholarly activities of individuals who obtained their Fellow of the Royal College of Physicians of Canada (FRCPC) designation in Radiation Oncology between 2000 and 2012, with (n = 57) or without (n = 230) UTDRO Fellowship training, was conducted. Almost all UTDRO Fellowship graduates were employed as staff radiation oncologists (291/293), and most of those employed were associated with additional academic (130/293), research (53/293), or leadership (68/293) appointments. Thirty-eight percent (101/263) of alumni responded to the online survey. The top two reasons for completing the Fellowship were to gain specific clinical expertise and exposure to research opportunities. Respondents were very satisfied with their training experience, and the vast majority (99%) would recommend the program to others. Most (96%) felt that completing the Fellowship was beneficial to their career development. University of Toronto, Department of Radiation Oncology Fellowship alumni were more likely to hold university, research, and leadership appointments, and author significantly more publications than those with FRCPC designation without fellowship training from UTDRO. The UTDRO Fellowship Program has been successful since its inception, with the majority of graduates reporting positive training experiences, benefits to scholarly output, and professional development for their post-fellowship careers. Key features that would optimize the fellowship experience and its long-term impact on trainees were also identified.

Defining radio-recurrent intra-prostatic target volumes using PSMA-targeted PET/CT and multi-parametric MRI

Purpose

Our purpose was to evaluate intra-prostatic cancer volumes for salvage radiotherapy in men with recurrent prostate cancer confined to the prostate post-primary radiotherapy using mpMRI and 18F-DCFPyL PET/CT (PET).

Methods

Men with biochemical failure post-primary radiotherapy were enrolled in a multi-centre trial investigating mpMRI and PET. All men with isolated intra-prostatic recurrence are included in this secondary analysis. The intra-prostatic gross tumour volume (GTV) was manually delineated on mpMRI and was also delineated on PET using three methods: 1. manually, 2. using a 30% threshold of maximum intra-prostatic standard uptake value (SUVmax), and 3. using a 67% threshold of this SUVmax. Clinical target volumes (CTV) including expansions on each GTV were generated. Conformity indices were performed between the mpMRI CTV and each PET CTV. Correlation with biopsy and clinical outcomes were performed.

Results

Of the 36 men included, 30 (83%) had disease in two quadrants or less using the combination of mpMRI and PET. Mean target volume (union of CTV on mpMRI and CTV manually delineated on PET) was 12.2 cc (49% of prostate gland volume). 12/36 (33%) men had a biopsy. Per-patient sensitivity was 91% for mpMRI and 82% for PET.

Conclusions

mpMRI and PET provide complementary information for delineation of intra-prostatic recurrent disease. Union of CTV on mpMRI and PET is often less than 50% of the prostate, suggesting this imaging could help define a target for focal salvage therapy.

Improving Data Integrity in Public Health: A Case Study of an Outbreak Management System in Nigeria

Because of existing data collection and data integrity challenges in Nigeria, the COVID-19 pandemic posed an unprecedented challenge for data and its use in decision making because of the speed and scale of the necessary response. Using a human-centered design approach to co-create an outbreak management system streamlined data and sample collection and management to improve data collection and integrity.

The completeness and accuracy of data in the Nigerian health care system is a challenge. Studies have shown that the data quality, and by extension data integrity, has been suboptimal and thus poses a barrier to strengthening service delivery. This article showcases how the design process sparked the concept for an intervention to improve the integrity of public health data being collected in Nigeria.

In collaboration with the Nigerian Institute of Medical Research (NIMR) and Lifebank, the Co-creation Hub team conducted formative research with the coronavirus disease (COVID-19) test center managers at NIMR. The insights informed the development of the features for an outbreak management system. These features were refined through an iterative process of development and continuous feedback from the end users.

NIMR reported an improvement in its data collection process and data integrity. They reported that (1) almost all data collection by the test center was now automated, thereby minimizing the proportion of inaccurate and repeat entry in comparison to data collected in other parts of the same center; (2) the auto-validation feature of the system ensured that all required fields of a patient’s information were completed and verified, thereby ensuring 100% data completeness; and (3) the validation and verification feature ensured that patients’ contact information was validated.

The integration of this intervention into the current health information system ensures an improvement in the accuracy and validity of health care data being collected and stored.

Is Remote Learning as Effective as In-Person Learning for Contouring Education? A Prospective Comparison of Face-to-Face vs. Online Delivery of the Anatomy and Radiology Contouring Bootcamp

PURPOSE

The Anatomy and Radiology Contouring (ARC) Bootcamp was a face-to-face (F2F) intervention providing integrated education for radiation oncology (RO) residents and medical physicists. To increase access, we launched an online offering in 2019. We evaluated the impact of the online course on participants' knowledge acquisition, contouring skills, and self-confidence by comparing it to the F2F course.  METHODS AND MATERIALS: Using modules, the online course offers similar content to the F2F comparator. Participants from the 2019 F2F and the 2019-2020 online course completed pre- and post-evaluations, assessing anatomy/radiology knowledge, contouring skills, self-confidence, and course satisfaction.

RESULTS

There were 180 (F2F: n=40; online: n=140) enrolled and 57 (F2F: n=30; online: n=27) participants completed both evaluations. The online course had a wider geographic participation (19 countries) than F2F (4 countries). F2F had primarily RO resident participation (80%), compared to online (41%). Both cohorts demonstrated similar improvements in self-confidence pertaining to their anatomy/radiology knowledge, contouring skills, and in interpreting radiology images (all p < 0.001). Both the online (mean ± SD improvement: 6.6 ± 6.7 on a 40-point scale; p < 0.001) and F2F (3.7 ± 5.7; p=0.002) groups showed anatomy/radiology knowledge improvement. Only the F2F group demonstrated improvement with the contouring assessment (F2F: 0.10 ± 0.17 on a 1-point Dice scale; p=0.004; online: 0.07 ± 0.16; p=0.076). Both cohorts perceived the course as a positive experience (F2F: 4.8 ± 0.4 on a 5-point scale; online: 4.5 ± 0.6), stated it would improve their professional practice (F2F: 4.6 ± 0.5; online: 4.2 ± 0.8), and said they would recommend it to others (F2F: 4.8 ± 0.4; online: 4.4 ± 0.6).

CONCLUSIONS

The online ARC Bootcamp demonstrated improved self-confidence, knowledge scores, and high satisfaction levels among participants. The offering had lower completion rates but was more accessible to geographic regions, provided a flexible learning experience, and allowed for ongoing education during the COVID-19 pandemic.

Implementation and evaluation of an online anatomy, radiology and contouring bootcamp for radiation therapists

BACKGROUND

As new treatments and technologies have been introduced in radiation oncology, the clinical roles of radiation therapists (RTs) have expanded. However, there are few formal learning opportunities for RTs. An online, anatomy, radiology and contouring bootcamp (ARC Bootcamp) originally designed for medical residents was identified as a prospective educational tool for RTs. The purpose of this study was to evaluate an RT edition of the ARC Bootcamp on knowledge, contouring, and confidence, as well as to identify areas for future modification.

METHODS

Fifty licensed RTs were enrolled in an eight-week, multidisciplinary, online RT ARC Bootcamp. Contouring practice was available throughout the course using an online contouring platform. Outcomes were evaluated using a pre-course and post-course multiple-choice quiz (MCQ), contouring evaluation and qualitative self-efficacy and satisfaction survey.

RESULTS

Of the fifty enrolled RTs, 30 completed the course, and 26 completed at least one of the post-tests. Nineteen contouring dice similarity coefficient (DSC) scores were available for paired pre- and post-course analysis. RTs demonstrated a statistically significant increase in mean DSC scoring pooled across all contouring structures (mean ± SD improvement: 0.09 ± 0.18 on a scale from 0 to 1, p=0.020). For individual contouring structures, 3/15 reached significance in contouring improvement. MCQ scores were available for 26 participants and increased after RT ARC Bootcamp participation with a mean ± SD pre-test score of 18.6 ± 4.2 (46.5%); on a 40-point scale vs. post-test score of 24.5 ± 4.3 (61.4%) (p < 0.001). RT confidence in contouring, anatomy knowledge and radiographic identification improved after course completion (p < 0.001). Feedback from RTs recommended more contouring instruction, less in-depth anatomy review and more time to complete the course.

CONCLUSIONS

The RT ARC Bootcamp was an effective tool for improving anatomy and radiographic knowledge among RTs. The course demonstrated improvements in contouring and overall confidence. However, only approximately half of the enrolled RTs completed the course, limiting statistical power. Future modifications will aim to increase relevance to RTs and improve completion rates.

Design and Implementation of a Distant-Learning Clinical Research Mentorship Program: The Accra-Toronto Collaboration

PURPOSE

For many oncology training programs in low- and middle-income countries, dedicated time for research education and mentorship of trainees is limited. Here, we report a 1-year-long collaboration between a cancer center in Canada and one in Ghana with the aim of imparting clinical research skills and mentoring the research of radiation oncology residents.

METHODS

On the basis of a needs assessment conducted in Ghana, we designed a curriculum consisting of 13 weekly seminars delivered via videoconference, followed by a 1-year-long mentorship program to support research projects. The primary outcome was the feasibility of the program from seminars to manuscript preparation. We used multiple secondary outcomes to capture the learning experience with study-specific questionnaires. We evaluated critical thinking ability using the Berlin questionnaire. Funding was made available for research and travel to international conferences.

RESULTS

Five Ghanaian trainees submitted research proposals. Nine Canadian faculty members delivered the seminars and two served as methodology mentors, and two Ghanaian faculty acted as local supervisors. Feedback questionnaires from all participants showed that they agreed strongly that they would recommend the sessions to another resident (75%), that the objectives were clear (71%), and that the topics were useful for their training (73%). At the end of the program, two Ghanaian trainees finalized their manuscripts and one was published.

CONCLUSION

Here, we report on the implementation of a mentorship program focused on research methods and evidence-based medicine in sub-Saharan Africa. The program was successful in the drafting and publication of abstracts and manuscripts by local trainees.

Comparison of Multiparametric Magnetic Resonance Imaging-Targeted Biopsy With Systematic Transrectal Ultrasonography Biopsy for Biopsy-Naive Men at Risk for Prostate Cancer: A Phase 3 Randomized Clinical Trial

Importance

Magnetic resonance imaging (MRI) with targeted biopsy is an appealing alternative to systematic 12-core transrectal ultrasonography (TRUS) biopsy for prostate cancer diagnosis, but has yet to be widely adopted.

Objective

To determine whether MRI with only targeted biopsy was noninferior to systematic TRUS biopsies in the detection of International Society of Urological Pathology grade group (GG) 2 or greater prostate cancer.

Design, Setting, and Participants

This multicenter, prospective randomized clinical trial was conducted in 5 Canadian academic health sciences centers between January 2017 and November 2019, and data were analyzed between January and March 2020. Participants included biopsy-naive men with a clinical suspicion of prostate cancer who were advised to undergo a prostate biopsy. Clinical suspicion was defined as a 5% or greater chance of GG2 or greater prostate cancer using the Prostate Cancer Prevention Trial Risk Calculator, version 2. Additional criteria were serum prostate-specific antigen levels of 20 ng/mL or less (to convert to micrograms per liter, multiply by 1) and no contraindication to MRI.

Interventions

Magnetic resonance imaging-targeted biopsy (MRI-TB) only if a lesion with a Prostate Imaging Reporting and Data System (PI-RADS), v 2.0, score of 3 or greater was identified vs 12-core systematic TRUS biopsy.

Main Outcome and Measures

The proportion of men with a diagnosis of GG2 or greater cancer. Secondary outcomes included the proportion who received a diagnosis of GG1 prostate cancer; GG3 or greater cancer; no significant cancer but subsequent positive MRI results and/or GG2 or greater cancer detected on a repeated biopsy by 2 years; and adverse events.

Results

The intention-to-treat population comprised 453 patients (367 [81.0%] White, 19 [4.2%] African Canadian, 32 [7.1%] Asian, and 10 [2.2%] Hispanic) who were randomized to undergo TRUS biopsy (226 [49.9%]) or MRI-TB (227 [51.1%]), of which 421 (93.0%) were evaluable per protocol. A lesion with a PI-RADS score of 3 or greater was detected in 138 of 221 men (62.4%) who underwent MRI, with 26 (12.1%), 82 (38.1%), and 30 (14.0%) having maximum PI-RADS scores of 3, 4, and 5, respectively. Eighty-three of 221 men who underwent MRI-TB (37%) had a negative MRI result and avoided biopsy. Cancers GG2 and greater were identified in 67 of 225 men (30%) who underwent TRUS biopsy vs 79 of 227 (35%) allocated to MRI-TB (absolute difference, 5%, 97.5% 1-sided CI, -3.4% to ∞; noninferiority margin, -5%). Adverse events were less common in the MRI-TB arm. Grade group 1 cancer detection was reduced by more than half in the MRI arm (from 22% to 10%; risk difference, -11.6%; 95% CI, -18.2% to -4.9%).

Conclusions and Relevance

Magnetic resonance imaging followed by selected targeted biopsy is noninferior to initial systematic biopsy in men at risk for prostate cancer in detecting GG2 or greater cancers.

Trial Registration

ClinicalTrials.gov Identifier: NCT02936258.

Clinical research mentorship programme (CRMP) for radiation oncology residents in Africa-building capacity through mentoring

Research skills are mandatory for all oncology residency training programmes. Creating the environment to foster skills and passion can be a challenge in all settings, and a unique challenge in low and middle income countries (LMICs). Tremendous clinical workload places exceptional demand on clinician teachers, research infrastructure and access to research collaborators with diverse methodological skill sets can be limited. International collaborations, and in particular relationship partnerships (Whitehead et al ((2018) Acad Med 93 1760-1763)) can be a useful approach to bridge resource gaps and enrich the support available to trainees (Research EoH ((2014) TDR/ESSENCE/2.14)). The Clinical Research Mentorship Programme (CRMP) is a collaborative initiative created by the University of Toronto Department of Radiation Oncology, Princess Margaret Cancer Centre, delivered in collaboration with LMIC radiation oncology residency programmes with the primary goal of enriching the research experience of LMIC oncology trainees. It was inspired by observing a need, an enthusiasm to collaborate and some seed funding that supported the idea. At the heart of the programme is a formalised relationship, a triad, between a LMIC oncology trainee, their local supervisor and a mentor from Toronto. Within the collaborative environment created between the LMIC and high income country (HIC) institutions, enabled by remote learning technologies, a 12-week research methods seminar kick starts a year-long mentorship for the trainee on their research question. The goal is to enrich the quality of the research experience for the trainee, resulting in dissemination of research findings in international conferences and publications. A standard evaluation package is used (Vuple et al ((2021) 6 919-928)). In this paper, through a description of our collaboration, we will highlight how a distant mentorship programme was used to enhance clinical research mentorship skills for radiation oncology trainees in Africa. We hope the format we have chosen will continue to demonstrate effectiveness for our trainees, sustainability for our faculty and institutions and will serve as one mechanism to build radiation capacity for LMIC through collaboration, mentorship and research.

A multiobserver study investigating the effectiveness of prostatic multiparametric magnetic resonance imaging to dose escalate corresponding histologic lesions using high-dose-rate brachytherapy

PURPOSE

Using multiparametric MRI data and the pathologic data from radical prostatectomy specimens, we simulated the treatment planning of dose-escalated high-dose-rate brachytherapy (HDR-BT) to the Multiparametric MRI dominant intraprostatic lesion (mpMRI-DIL) to compare the dose potentially delivered to the pathologically confirmed locations of the high-grade component of the cancer.

METHODS AND MATERIALS

Pathologist-annotated prostatectomy midgland histology sections from 12 patients were registered to preprostatectomy mpMRI scans that were interpreted by four radiologists. To simulate realistic HDR-BT, we registered each observer's mpMRI-DILs and corresponding histology to two transrectal ultrasound images of other HDR-BT patients with a 15-Gy whole-gland prescription. We used clinical inverse planning to escalate the mpMRI-DILs to 20.25 Gy. We compared the dose that the histopathology would have received if treated with standard treatment plans to the dose mpMRI-targeting would have achieved. The histopathology was grouped as high-grade cancer (any Gleason Grade 4 or 5) and low-grade cancer (only Gleason Grade 3).

RESULTS

212 mpMRI-targeted HDR-BT plans were analyzed. For high-grade histology, the mpMRI-targeted plans achieved significantly higher median [IQR] D98 and D90 values of 18.2 [16.7-19.5] Gy and 19.4 [17.8-20.9] Gy, respectively, in comparison with the standard plans (p = 0.01 and p = 0.003). For low-grade histology, the targeted treatment plans would have resulted in a significantly higher median D90 of 17.0 [16.1-18.4] Gy in comparison with standard plans (p = 0.015); the median D98 was not significantly higher (p = 0.2).

CONCLUSIONS

In this retrospective pilot study of 12 patients, mpMRI-based dose escalation led to increased dose to high-grade, but not low-grade, cancer. In our data set, different observers and mpMRI sequences had no substantial effect on dose to histologic cancer.

Development, Implementation, and Initial Participant Feedback of an Online Anatomy and Radiology Contouring Bootcamp in Radiation Oncology

BACKGROUND

The Anatomy and Radiology Contouring (ARC) Bootcamp was a face-to-face (F2F) course designed to ensure radiation oncology residents were equipped with the knowledge and skillset to use radiation therapy techniques properly. The ARC Bootcamp was proven to be a useful educational intervention for improving learners' knowledge of anatomy and radiology and contouring ability. An online version of the course was created to increase accessibility to the ARC Bootcamp and provide a flexible, self-paced learning environment. This study aimed to describe the instructional design model used to create the online offering and report participants' motivation to enroll in the course and the online ARC Bootcamp's strengths and improvement areas.

METHODS

The creation of the online course followed the analysis, design, development, implementation, and evaluation (ADDIE) framework. The course was structured in a linear progression of locked modules consisting of radiology and contouring lectures, anatomy labs, and integrated evaluations.

RESULTS

The online course launched on the platform Teachable in November 2019, and by January 2021, 140 participants had enrolled in the course, with 27 participants completing all course components. The course had broad geographic participation with learners from 19 different countries. Of the participants enrolled, 34% were female, and most were radiation oncology residents (56%), followed by other programs (24%), such as medical physics residents or medical students. The primary motivator for participants to enroll was to improve their subject knowledge/skill (44%). The most common strength identified by participants was the course's quality (41%), and the most common improvement area was to incorporate more course content (41%).

CONCLUSIONS

The creation of the online ARC Bootcamp using the ADDIE framework was feasible. The course is accessible to diverse geographic regions and programs and provides a flexible learning environment; however, the course completion rate was low. Participants' feedback regarding their experiences will inform future offerings of the online course.

The value of 99mTc-sestamibi single-photon emission computed tomography-computed tomography in the evaluation and risk stratification of renal masses

INTRODUCTION

Differentiation of renal cell carcinoma (RCC) from oncocytoma is a common diagnostic dilemma. A few studies have shown that ^99mTc-sestamibi (MIBI) imaging has the potential to characterize indeterminate renal masses. This comparative study evaluated the utility of MIBI single-photon emission computed tomography-computed tomography (SPECT-CT) in the assessment and risk stratification of renal masses.

METHODS

A total of 29 patients with 31 renal masses who had cross-sectional imaging and MIBI SPECT-CT were included. Lesions were categorized as either MIBI-positive or -negative on SPECT-CT. Individual lesion density ranged from 22-56 Hounsfield units (HU) on the non-contrast CT part of SPECT-CT. Quantitative relative MIBI uptake was calculated by measuring tumor to ipsilateral renal parenchymal uptake. The imaging results were correlated with histopathology.

RESULTS

All oncocytic lesions, including seven oncocytomas and one hybrid oncocytic chromophobe tumor (100%), were positive on MIBI. One chromophobe RCC showed low-grade MIBI uptake. The remaining RCC subtypes, including 15 clear-cell, four papillary, two mixed clear-cell and papillary, and one chromophobe, were MIBI-negative. The quantitative relative tumor uptake showed statistically significant higher uptake in the low-risk/oncocytic lesions compared to RCCs.

CONCLUSIONS

This study demonstrates that MIBI SPECT-CT is valuable in the characterization of indeterminate renal masses. The combination of MIBI uptake on SPECT and lesion density on non-contrast CT can be used for risk stratification of renal masses. This technique may reduce the need for further imaging (multiphasic CT or magnetic resonance imaging), renal mass biopsy, or surgical resection of low-risk renal masses. Subsequently, more patients could be followed with active surveillance.

Magnetic resonance imaging-guided transurethral ultrasound ablation in patients with localised prostate cancer: 3-year outcomes of a prospective Phase I study

OBJECTIVES

To report the 3-year follow-up of a Phase I study of magnetic resonance imaging (MRI)-guided transurethral ultrasound ablation (TULSA) in 30 men with localised prostate cancer. Favourable 12-month safety and ablation precision were previously described.

PATIENTS AND METHODS

As a mandated safety criterion, TULSA was delivered as near whole-gland ablation, applying 3-mm margins sparing 10% of peripheral prostate tissue in 30 men. After 12-month biopsy and MRI, biannual follow-up included prostate-specific antigen (PSA), adverse events (AEs), and functional quality-of-life assessment, with repeat systematic biopsy at 3 years.

RESULTS

A 3-year follow-up was completed by 22 patients. Between 1 and 3 years, there were no new serious or severe AEs. Urinary and bowel function remained stable. Erectile function recovered by 1 year and was stable at 3 years. The PSA level decreased 95% to a median (interquartile range) nadir of 0.33 (0.1-0.4) ng/mL, stable to 0.8 (0.4-1.6) ng/mL at 3 years. Serial biopsies identified clinically significant disease in 10/29 men (34%) and any cancer in 17/29 (59%). By 3 years, seven men had recurrence (four histological, three biochemical) and had undergone salvage therapy without complications (including six prostatectomies). At 3 years, three of 22 men refused biopsy, and two of the 22 (9%) had clinically significant disease (one new, one persistent). Predictors of salvage therapy requirement included less extensive ablation coverage and higher PSA nadir.

CONCLUSION

With 3-year Phase I follow-up, TULSA demonstrates safe and precise ablation for men with localised prostate cancer, providing predictable PSA and biopsy outcomes, without affecting functional abilities or precluding salvage therapy.

SEVERE HYPERCALCEMIA SECONDARY TO PARAFFIN OIL INJECTIONS IN A BODYBUILDER WITH SIGNIFICANT FINDINGS ON SCINTIGRAPHY

Objective

Non-parathyroid hormone (PTH) mediated hypercalcemia in young patients is rare. It encompasses a broad differential including malignancy, granulomatous diseases, Addison disease, and toxicity of vitamin A and D. We present an unusual case of non-PTH mediated hyper-calcemia in a previously healthy bodybuilder, secondary to multifocal granulomatous disease from paraffin oil injections.

Methods

The patient was evaluated with laboratory tests including serum calcium, 25-hydroxyvitamin D, 1,25-hydroxyvitamin D, parathyroid hormone, and parathyroid hormone-related peptide. Imaging studies such as thorax computed tomography and bone scans were also performed.

Results

A 31-year-old male bodybuilder presented with severe hypercalcemia (corrected calcium 3.1 mmol/L) and renal failure (creatinine 840 μmol/L), with suppressed PTH 1.0 pmol/L (normal, 1.6 to 6.9 pmol/L), and 1,25-vitamin D 205 pmol/L (normal, 60 to 208 pmol/L). He had used anabolic steroids for bodybuilding purposes for 8 years, with the possibility that he may also have used paraffin oil injections. Computed tomography imaging along with patient history suggested multiple paraffinomas in the pectoralis muscles causing granulomatous foreign body reaction as a potential cause for his hypercalcemia. He was prescribed a trial of prednisone, but he discontinued it due to symptoms of acne. Unfortunately, due to poor adherence with medical direction, management of his hypercalcemia remains challenging with inconsistent use of steroids and pamidronate infusions.

Conclusion

Granulomatous foreign-body reactions are a rare side effect of paraffin oil injections used for muscle augmentation. These can lead to serious long-term side effects of severe hypercalcemia and renal failure, as seen in our patient. Prognosis is generally poor, with long term steroids as the preferred treatment.

Integrating Survivorship Care Into a Radiation Medicine Program

Introduction

An important but often overlooked component of caring for cancer patients is survivorship care, provided after the completion of active treatment in order to facilitate transition into the next surveillance phase. A survivorship program was developed to deliver a one-on-one education session on healthy lifestyle behaviours and available resources to help patients transition to their post-treatment life. This study reports the outcome of this pilot survivorship care program provided to breast cancer patients completing radiation therapy. Program delivery format and content were evaluated for effectiveness, applicability, and feasibility. 

Methods and materials

Between March 2017 and August 2018, 124 breast cancer patients, nearing completion of their curative intent radiation treatments, participated in this centre-specific survivorship program. The survivorship program entailed a one on one education session delivered to breast cancer patients within the last two weeks of their radiation treatment. Participants were provided a Microsoft PowerPoint presentation, information pamphlet, and evaluation form to provide feedback on materials and presentation. Survivorship education sessions were delivered by study staff or staff scheduled in the Pre-Radiotherapy Patient Assessment role. Follow-up phone calls were conducted post-session delivery to determine the ongoing applicability of survivorship material. Staff was also given an evaluation form upon completion of the trial to measure the session feasibility.

Results

Of the 124 participants in the study, 69 (56%) provided feedback. Results showed that 98% of participants felt the information provided either confirmed what they were already doing (44%) or encouraged them to consider a lifestyle change (54%). Additionally, 70% reported feeling more confident after completing the session. Staff survey results reported that 87.5% agreed or strongly agreed that these sessions were beneficial and valuable to patients

Conclusions

Delivering one-on-one education sessions to individual participants focusing on healthy lifestyle measures garnered a positive response from participants, increasing their confidence and knowledge for making lifestyle changes. While staff survey results pointed strongly in favour of continuing with the survivorship sessions, it was shown that the methods of delivery trialed in this study were not feasible to be implemented on a larger scale. With some workflow modification, implementing a survivorship care program in our cancer centre is a possible and important aspect of a patient’s treatment journey.

Promoting Career Selection Through a Comprehensive Enrichment Experience: A Review of the Canadian Radiation Oncology Summer Studentship

PURPOSE

The impact that early clinical exposure to radiation oncology has on medical students' understanding of oncology and career choice is understudied. This study aims to review the experience and outcomes of medical students who participated in the Canadian Association of Radiation Oncology-Canadian Radiation Oncology Foundation 6-week summer studentship.

METHODS AND MATERIALS

Medical students who participated in the nationally funded studentship from 2014 to 2018 were asked to fill out a survey after completing the program. The survey asked about student experience related to radiation oncology before the studentship, student satisfaction with the studentship (scale of 1-5; 5 = outstanding, 3 = meets expectations, 1 = unsatisfactory), and student willingness to recommend it to other students (scale of 1-10; 1 = strongly disagree, 5 = neutral, 10 = strongly agree). The effect of studentship on interest in the specialty was assessed (scale of 1-10; 1 = strongly disagree, 5 = neutral, 10 = strongly agree), including intent to direct their career toward radiation oncology. Match rates to radiation oncology residency are reported for students who participated in the studentship from 2013 to 2016.

RESULTS

All 31 students responded to the survey. Overall, the program was highly rated: inclusion of a broad range of clinical problems (mean = 4.6/5); opportunity to learn assessment, investigation, and management (mean = 4.2/5); and overall educational value (mean = 4.8/5). Poststudentship, most students reported an increased interest in oncology (76%, n = 22/29), and specifically radiation oncology (83%, n = 24/29). They would highly recommend this program to another medical student (mean = 9.8/10). The average percentage of these students entering a radiation oncology career (30.5%) each year was higher than national residency match rates in radiation oncology (0.7%).

CONCLUSIONS

Clinical exposure to radiation oncology through a nationally funded Canadian Association of Radiation Oncology-Canadian Radiation Oncology Foundation summer studentship positively affected medical student interest in oncology. This study suggests a potential effect of the studentship program on career selection of radiation oncology.

Multiparametric magnetic resonance imaging of multifocal prostate cancer to reveal intra-prostatic genomic heterogeneity and novel radio-genomic correlates: Results of the Smarter Prostate Interventions and Therapeutics (SPIRIT) study

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Background: Multi-focality and heterogeneity in prostate cancer can confound the selection of appropriate clinical management. Our study aimed to explore radio-genomic correlations using multiparametric magnetic resonance imaging (mpMRI) against a histopathologic reference standard. Methods: Eight men with prostate cancer who underwent mpMRI followed by prostatectomy were selected for this pilot. Whole-mount histopathology was digitized and co-registered to corresponding MRI slices using a validated high-fidelity methodology.(1) Foci, including central/transitional and peripheral zone lesions were identified by a pathologist, and contoured on digitized histopathology specimens and these digitized maps were used to guide macrodissection of the individual foci for genomic copy-number aberration (CNA) analysis. Correlation of radiomics signatures with the histologic findings and genomic analysis was performed. Results: We found a broad range of CNAs revealing inter-patient and intra-prostatic heterogeneity. Recurrently-altered loci ( e.g., 8p21) containing genes of known significance ( e.g., NKX3-1) were observed. Only radiomic features derived from apparent diffusion coefficient (ADC) independently correlated with both Gleason grade (Rho=-0.62, p=0.003) and median CNA burden (Rho=-0.68, p<0.001). While greater CNA burden expectedly correlated with higher grade, intermediate-grade (Gleason score 3+4 or 4+3) lesions appeared more like either high-grade (Gleason scores ≥4+4) or low-grade (Gleason score 3+3) disease when clustered based on CNA and ADC metrics. Conclusions: These findings suggest ADC derived radiomic metrics may be a useful imaging biomarker across both central and peripheral zone lesion and could aid in further characterization of intra-prostatic biologic heterogeneity. These proof-of-principle data reveal novel radio-genomic correlations that could supplement histologic grading and conventional imaging, thus warranting expanded study and validation. 1) Int J Rad Oncol Biol Phys. 2016; 96(1):188-96.

Response to commentary on "the middle fossa approach with self-drilling screws: a novel technique for BONEBRIDGE implantation"

The aim of this letter is to respond to a commentary on a published article on the middle fossa approach to BONEBRIDGE implantation with self-drilling screws published by the senior authors.

The use of PET/MRI for imaging rectal cancer

Combined PET/MRI is a proposed imaging modality for rectal cancer, leveraging the advantages of MRI and 18F-fluorodeoxyglucose PET. Rectal cancer PET/MRI protocols typically include dedicated pelvis bed positions utilizing small field-of-view T2-weighted imaging. For staging of the primary tumor, PET/MRI can help delineate the extent of tumor better as well as the extent of tumor beyond the muscularis propria. PET uptake may help characterize small lymph nodes, and the use of hepatobiliary phase imaging can improve the detection of small hepatic metastases. The most beneficial aspect of PET/MRI may be in treatment response, although current data are limited on how to combine PET and MRI data in this setting. Limitations of PET/MRI include the inability to detect small pulmonary nodules and issues related to attenuation correction, although the development of new attenuation correction techniques may address this issue. Overall PET/MRI can improve the staging of rectal cancer, although this potential has yet to be fulfilled.

Beyond adenocarcinoma: MRI of uncommon rectal neoplasms and mimickers

OBJECTIVE

To provide a review of rare rectal tumors beyond adenocarcinoma.

RESULTS

Rectal cancer is a common malignancy, both in the United States and abroad. In addition to adenocarcinoma, abdominal radiologists will encounter a variety of other less common rectal masses, both benign and malignant neoplasms as well as non-neoplastic mimickers. Familiarity with these conditions and their characteristic features on MRI is useful in clinical practice. In this article, a number of such conditions are discussed, with an emphasis on distinguishing features on MRI of the rectum.

CONCLUSION

Familiarity with the MRI features of rare rectal tumors beyond adenocarcinoma, as well as a small number of non-neoplastic mimics, is important for abdominal imagers to make diagnostic differentials and to assist in treatment planning.

Rectal cancer lexicon: consensus statement from the society of abdominal radiology rectal & anal cancer disease-focused panel

Standardized terminology is critical to providing consistent reports to referring clinicians. This lexicon aims to provide a reference for terminology frequently used in rectal cancer and reflects the consensus of the Society of Abdominal Radiology Disease Focused Panel in Rectal cancer. This lexicon divided the terms into the following categories: primary tumor staging, nodal staging, treatment response, anal canal anatomy, general anatomy, and treatments.

The middle fossa approach with self-drilling screws: a novel technique for BONEBRIDGE implantation

Background

Bone conduction implants can be used in the treatment of conductive or mixed hearing loss. The BONEBRIDGE bone conduction implant (BB-BCI) is an active, transcutaneous device. BB-BCI implantation can be performed through either the transmastoid or retrosigmoid approach with their respective limitations. Here, we present a third, novel approach for BB-BCI implantation.

Objective

Describe the detailed surgical technique of BB-BCI implantation through a middle fossa approach with self-drilling screws and present preliminary audiometric outcome data following this approach.

Methods

A single institution, retrospective chart review was completed for patients implanted with the BB-BCI via the middle fossa approach. Preoperative planning and modelling were performed using 3D Slicer. Audiological testing was performed pre- and post-operatively following standard audiometric techniques.

Results

Forty patients underwent BB-BCI implantation using the middle fossa approach. Modelling techniques allowed for implantation through the use of external landmarks, obviating the need for intraoperative image guidance. The surgical technique was refined over time through experience and adaptation. Mean follow-up was 29 months (range 3–71 months) with no surgical complications, favourable cosmesis, and expected audiometric outcomes. An average functional gain of 39.6 dB (± 14.7 SD) was found.

Conclusion

The middle fossa technique with self-drilling screws is a safe and effective option for BONEBRIDGE implantation. As a reference for other groups considering this approach, an annotated video has been included as a supplement to the study.

Electronic supplementary material

The online version of this article (10.1186/s40463-019-0354-7) contains supplementary material, which is available to authorized users.

LI-RADS: a conceptual and historical review from its beginning to its recent integration into AASLD clinical practice guidance

The Liver Imaging Reporting and Data System (LI-RADS^®) is a comprehensive system for standardizing the terminology, technique, interpretation, reporting, and data collection of liver observations in individuals at high risk for hepatocellular carcinoma (HCC). LI-RADS is supported and endorsed by the American College of Radiology (ACR). Upon its initial release in 2011, LI-RADS applied only to liver observations identified at CT or MRI. It has since been refined and expanded over multiple updates to now also address ultrasound-based surveillance, contrast-enhanced ultrasound for HCC diagnosis, and CT/MRI for assessing treatment response after locoregional therapy. The LI-RADS 2018 version was integrated into the HCC diagnosis, staging, and management practice guidance of the American Association for the Study of Liver Diseases (AASLD). This article reviews the major LI-RADS updates since its 2011 inception and provides an overview of the currently published LI-RADS algorithms.

White paper of the Society of Abdominal Radiology hepatocellular carcinoma diagnosis disease-focused panel on LI-RADS v2018 for CT and MRI

The Liver Imaging and Reporting Data System (LI-RADS) is a comprehensive system for standardizing the terminology, technique, interpretation, reporting, and data collection of liver imaging with the overarching goal of improving communication, clinical care, education, and research relating to patients at risk for or diagnosed with hepatocellular carcinoma (HCC). In 2018, the American Association for the Study of Liver Diseases (AASLD) integrated LI-RADS into its clinical practice guidance for the imaging-based diagnosis of HCC. The harmonization between the AASLD and LI-RADS diagnostic imaging criteria required minor modifications to the recently released LI-RADS v2017 guidelines, necessitating a LI-RADS v2018 update. This article provides an overview of the key changes included in LI-RADS v2018 as well as a look at the LI-RADS v2018 diagnostic algorithm and criteria, technical recommendations, and management suggestions. Substantive changes in LI-RADS v2018 are the removal of the requirement for visibility on antecedent surveillance ultrasound for LI-RADS 5 (LR-5) categorization of 10-19 mm observations with nonrim arterial phase hyper-enhancement and nonperipheral "washout", and adoption of the Organ Procurement and Transplantation Network definition of threshold growth (≥ 50% size increase of a mass in ≤ 6 months). Nomenclatural changes in LI-RADS v2018 are the removal of -us and -g as LR-5 qualifiers.

Apixaban and Rosuvas--tatin Pharmacokinetics in Nonalcoholic Fatty Liver Disease

There is little known about the impact of nonalcoholic fatty liver disease (NAFLD) on drug metabolism and transport. We examined the pharmacokinetics of oral apixaban (2.5 mg) and rosuvastatin (5 mg) when administered simultaneously in subjects with magnetic resonance imaging-confirmed NAFLD (N = 22) and healthy control subjects (N = 12). The area under the concentration-time curve to the last sampling time (AUC_0-12) values for apixaban were not different between control and NAFLD subjects (671 and 545 ng/ml × hour, respectively; P = 0.15). Similarly, the AUC_0-12 values for rosuvastatin did not differ between the control and NAFLD groups (25.4 and 20.1 ng/ml × hour, respectively; P = 0.28). Furthermore, hepatic fibrosis in NAFLD subjects was not associated with differences in apixaban or rosuvastatin pharmacokinetics. Decreased systemic exposures for both apixaban and rosuvastatin were associated with increased body weight (P < 0.001 and P < 0.05, respectively). In multivariable linear regression analyses, only participant weight but not NAFLD, age, or SLCO1B1/ABCG2/CYP3A5 genotypes, was associated with apixaban and rosuvastatin AUC_0-12 (P < 0.001 and P = 0.06, respectively). NAFLD does not appear to affect the pharmacokinetics of apixaban or rosuvastatin.

Asymptomatic Clostridium difficile carriage rate post-fecal microbiota transplant is low: a prospective clinical and stool assessment

OBJECTIVES

We aimed to assess the asymptomatic Clostridium difficile carriage rates following fecal microbiota transplantation (FMT).

METHODS

All patients who underwent FMT for recurrent Clostridium difficile infection (CDI) via colonoscopy or sigmoidoscopy between June 2013 and April 2015 and had a minimum of 8-week follow-up post FMT at two tertiary care referral centres were included in the study. Patients were prospectively followed both clinically and with stool assessments for 8 weeks post FMT. Assessments occurred at 1 week and 4 weeks post FMT to assess for failure. Failure was defined as presence of diarrhoeal symptoms and a positive CDI stool test by polymerase chain reaction for toxin gene (PCR) at any time point during the 8-week follow-up period. CDI stool testing using PCR was performed at weeks 1 and 4 post FMT in asymptomatic patients as well.

RESULTS

167 patients were included. Twenty-eight patients (16.7% (28/167)) were FMT failures throughout the 8-week period. At week 1, seven patients had already failed the FMT. Of the remaining 160 patients, 144 were asymptomatic, and among these, 141 were negative for C. difficile toxin gene by PCR. This resulted in an asymptomatic carriage rate of 2.1% (3/144). At week 4, 143 patients had not yet failed FMT. Of these patients 129 patients were asymptomatic and among those, 125 were negative by PCR, resulting in an asymptomatic carriage rate of 3% (3/129).

CONCLUSIONS

Asymptomatic carriage after FMT is rare. This suggests that testing for cure after FMT in asymptomatic patients is not necessary.