Efficacy of immune checkpoint inhibitors in alveolar soft-part sarcoma: results from a retrospective worldwide registry

BACKGROUND

Conventional cytotoxic drugs are not effective in alveolar soft-part sarcoma (ASPS). Immune checkpoint (programmed cell death protein 1/programmed death-ligand 1) inhibitors (ICIs) are promising drugs in ASPS. A worldwide registry explored the efficacy of ICI in ASPS.

MATERIALS AND METHODS

Data from adult patients diagnosed with ASPS and treated with ICI for advanced disease in expert sarcoma centers from Europe, Australia and North America were retrospectively collected, including demographics and data related to treatments and outcome.

RESULTS

Seventy-six ASPS patients, with a median age at diagnosis of 25 years (range 3-61 years), were registered. All patients received ICI for metastatic disease. Immunotherapy regimens consisted of monotherapy in 38 patients (50%) and combination in 38 (50%) (23 with a tyrosine kinase inhibitor). Among the 68 assessable patients, there were 3 complete responses and 34 partial responses, translating into an overall response rate of 54.4%. After a median follow-up of 36 months [95% confidence interval (CI) 32-40 months] since the start of immunotherapy, 45 (59%) patients have progressed on ICI, with a median progression-free survival (PFS) of 16.3 months (95% CI 8-25 months). Receiving ICI in first line (P = 0.042) and achieving an objective response (P = 0.043) correlated with a better PFS. Median estimated overall survival (OS) from ICI initiation has not been reached. The 12-month and 24-month OS rates were 94% and 81%, respectively.

CONCLUSIONS

This registry constitutes the largest available series of ASPS treated with ICI. Our results suggest that the ICI treatment provides long-lasting disease control and prolonged OS in patients with advanced ASPS, an ultra-rare entity with limited active therapeutic options.

Stereotactic Radiosurgery for Small Intact Brain Metastasis: A Comparative Evaluation of 3 Different Single Fraction Prescription Doses

PURPOSE/OBJECTIVE(S)

While single-fraction stereotactic radiosurgery (SRS) in the treatment of small brain metastases (SBM, ≤ 2 cm) is well established, prescription dosing varies considerably across institutions and clinical trials. The choice of prescription dose is a delicate balance between local failure (LF) and radiation necrosis (RN) risks. In the modern era, historically-established dosing thresholds may no longer be applicable. To evaluate the impact of prescription dose on outcomes, we performed a comparative analysis of patients with SBM treated with definitive SRS using three different prescriptions, at a single tertiary institution.

MATERIALS/METHODS

Consecutive patients with intact SBM treated with SRS from January 2017 and December 2021 were analyzed. Baseline patient characteristics and dosing parameters were abstracted from the medical record. To limit the integral brain dose when treating multiple brain metastases, the institutional practice was to reduce prescription dose as the total number of lesions increased (i.e., 24 Gy for ≤10 lesions, 22 Gy for 11-20, and 20 Gy for >20). A per lesion analysis, where each lesion was followed from the date of SRS to the last follow-up, was conducted with primary endpoints of LF and RN. Gray's test was used to compare the cumulative incidence of the LF and RN, with death as a competing risk. Factors affecting LF were analyzed using Cox hazard regression analysis.

RESULTS

A total of 1318 SBM in 250 patients received SRS and met the inclusion criteria. The median age was 62 years (range: 18-90), median KPS was 90 (range: 50-100) and 66% were female. The most common primary tumors were lung (55.5%) and breast cancers (26.4%). With a median follow-up of 12 months, 136 (11%) LF in 44 patients and 70 (5.7%) RN events in 46 patients occurred. The actuarial 1-year cumulative rate of LF was lower in lesions treated with 24 Gy (6.4%, 95% CI: 4.7-8.6%) or 22 Gy (5.8%, 95% CI: 3.7-8.7%) compared to 20 Gy (15.4%, 95% CI: 10.9-20.5%) (p<0.01). 22 Gy and 24 Gy prescription doses were associated with a 44% and 52% reduction in risk in LF compared to 20 Gy (HR: 0.56; 95% CI: 0.36-0.9; p = 0.01 and HR: 0.48; 95% CI: 0.31-0.74; p<0.01, respectively). In a subset analysis of radiosensitive tumors, 1-year LF rate was still lower with 24 Gy (7.4%, 95% CI: 5.3-9.9%) and 22 Gy (6.1%, 95% CI: 3.7-9.4%) than 20 Gy (15.7%, 95% CI: 11.2-21%) (p = 0.01). The cumulative 1-year RN rate numerically declined with dose, but was not statistically significantly different, with 3.6% (95% CI: 2.3-5.3%) for 24 Gy, 2.6% (95% CI: 1.3-4.8%) for 22 Gy and 1.4% (95% CI: 0.4-3.7%) for 20 Gy.

CONCLUSION

Patients treated with single fraction SRS to intact SBM were at increased risk of LF with prescription doses of 20 Gy compared to 22-24 Gy, without an increased risk of RN. Even in patients with radiosensitive histologies, higher LF rates were still observed following 20 Gy compared to 22-24 Gy.

A Comparison of Local Failure and Necrosis Following Different Radiosurgery Strategies for Large Brain Metastases

PURPOSE/OBJECTIVE(S)

Large brain metastases (LBMs) are associated with poor local control with single-fraction stereotactic radiosurgery (SRS) alone. Various alternative strategies have been developed, including fractionated SRS (FSRS) and staged SRS (SSRS) for intact LBMs, and resection with postoperative-SRS (postop-SRS) or preoperative-SRS (preop-SRS) for operable LBMs. The objective of this study is to compare local failure (LF) and radiation necrosis (RN) outcomes among these four management strategies to determine the optimal treatment paradigm.

MATERIALS/METHODS

Consecutive patients diagnosed with LBM (≥2 cm in maximum dimension) between July 2017 and January 2022 and treated with one of the aforementioned strategies at a single tertiary institution were evaluated. All immobilization, target contouring, margins, dose- and prescription selection followed pre-defined institutional guidelines. Primary endpoints included LF, symptomatic RN, or a composite endpoint of these two variables. Gray's test was used to compare the cumulative incidence of the LF and the composite endpoint, with death as a competing risk.

RESULTS

A total of 234 LBMs in 188 consecutive patients met the inclusion criteria. The median age was 65 years (range: 31-98), the median KPS was 80 (range: 50-100), and 58% were female. The most common primary tumors were lung (48%) and breast cancer (17%). The median maximum tumor diameter was 3.0 cm (range: 2.0-5.6). 47 (20%) lesions were treated with FSRS, 66 (28%) with SSRS, 74 (32%) with postop-SRS, and 47 (20%) with preop-SRS. With a median follow-up of 12 months, 22 (9%) LF and 11 (5%) RN events occurred. The 6-month and 1-year cumulative incidences of LF for the entire cohort were 5% (95% CI: 3%-9%) and 8% (95% CI: 5%-12%), respectively. The 6-month and 1-year LF rates were 4% (95% CI: 1%-13%) and 8% (95% CI: 3%-20%) for FSRS; 8% (95% CI: 3%-20%) and 8% (95% CI: 3%-20%) for SSRS; 7% (95% CI: 3%-15%) and 8% (95% CI: 3%-16%) for postop-SRS; 0 and 7% (95% CI: 2%-20%) for preop-SRS (p>0.05). The 1-year OS rates were favorable in resected patients (61% for postop-SRS and 82% for preop-SRS) compared to SRS alone strategies (45% for FSRS and 56% for SSRS) (p = 0.004). Similarly, RN events were significantly lower in resected patients treated with either bimodality approach (0 for postop-SRS and 4% for preop-SRS) than SRS standalone strategies (9% for FSRS and 8% SSRS) (p = 0.024). At 12 months, the cumulative probabilities of the composite endpoint were 13% (95% CI: 5%-25%) for FSRS, 15% (95% CI: 7%-25%) for SSRS, 9% (95% CI: 3%-17%) for postop-SRS, and 12% (95% CI: 4%-24%) for preop-SRS and not significantly different between the groups.

CONCLUSION

For medically operable patients with surgically resectable LBMs, a strategy of surgery and SRS, regardless of timing, is associated with favorable local control and reduced risk for RN. For unresected patients, either SSRS or FSRS is associated with similar local control, but slightly higher RN risk. Prospective comparative evaluation is warranted.

Retrospective Assessment of Surface Imaging Set up Accuracy for Intensity Modulated Proton Therapy of Comprehensive Breast Irradiation

PURPOSE/OBJECTIVE(S)

The purpose of this work is to retrospectively assess differences in pretreatment set-up between x-ray-based alignment (kV pair and/or CBCT) and the CatalystPT Surface Imaging System (C-RAD) to quantify accuracy and determine maximum deviation of intra-fractional motion in breast patients treated with proton therapy.

MATERIALS/METHODS

Breast patient setup differences were evaluated for ninety-seven patients (n = 97) treated by proton therapy between 2019 and 2022 at our institution. Each patient was initially aligned using C-RAD followed by orthogonal planar x-rays and/or CBCT to finalize pre-treatment localization. The couch coordinates from C-RAD immediately after patient positioning were captured and compared with the finalized couch coordinates using x-ray-based alignment. Additionally, the maximum 6D deviation of patient position recorded by C-RAD during the course of treatment was captured. Patient BMI and age were correlated with setup differences between C-RAD and x-ray imaging and evaluated using Pearson Correlation Coefficients (PCC) and Analysis of Variance (ANOVA) test.

RESULTS

The absolute mean displacement was calculated over the entire course of treatment and reported by comparing the absolute difference between C-RAD and x-ray setups for each patient. The absolute mean displacement difference calculated by the mean of all the patients was found to be 2.5±1.1 mm (lateral), 2.8±1.2 mm (longitudinal), 2.5±1.0 mm (vertical), 1.2±0.5° (Yaw), 1.0±0.5°(Pitch) and 1.0±0.5°(Roll). The relative mean displacement difference with respect to the couch coordinate finalized by x-ray imaging was calculated by the mean of all the patients and was found to be 3.9±1.8 mm (lateral), 4.8±1.7 mm (longitudinal), 3.1±1.6 mm (vertical), 1.2±0.7° (Yaw), 1.6±0.7°(Pitch) and 1.3±0.6°(Roll). The mean maximum deviation for the entire course of treatment reported by C-RAD for all the patients was calculated to be 3.3±0.9 mm. Statistically, there are no significant correlations between BMI or age for mean displacement difference (BMI: PCC = 0.18, p-value = 0.075, Age: PCC = 0.004, p-value = 0.80705) and maximum deviation (BMI: PCC = 0.023, p-value = 0.72, Age: PCC = -0.089, p-value = 0.37).

CONCLUSION

C-RAD was able to position breast patients to within 3 mm of the isocenter and monitor the intra-fractional motion of patients which was found to be 3.3±0.9 mm.

Patterns of Locoregional Failure After Ablative 5-Fraction Stereotactic MR-Guided on-Table Adaptive Radiation Therapy for Pancreatic Cancer

PURPOSE/OBJECTIVE(S)

SBRT for pancreatic ductal adenocarcinoma (PDAC) is routinely delivered with non-ablative dose to only gross disease resulting in locoregional failure (LRF) rates of >50%, most commonly near the celiac artery (CA) and/or superior mesenteric artery (SMA). It is unclear whether an alternative approach of prescribing ablative dose to gross disease plus elective coverage prevents and/or delays LRF. The study objective was to describe the incidence and anatomic distribution of LRF using this treatment approach.

MATERIALS/METHODS

A single institution retrospective analysis was performed of non-metastatic PDAC patients who received ablative stereotactic MR-guided on-table adaptive radiation therapy (A-SMART) on a 0.35T MR-Linac from 2018-2022. Median prescribed dose was 50 Gy/5 fractions. Elective coverage (EC), including a margin around the primary tumor, CA, and SMA, to 33-35 Gy/5 fractions became routine in 2019 using a simultaneous integrated boost; the porta hepatis was not routinely covered. LRFs were contoured and defined as out-of-field (OOF), marginal (M), or in-field (IF) if >80%, 20-80%, or <20% of it was outside of the most peripheral prescription isodose line.

RESULTS

One hundred four patients were evaluated (87% head tumors). 94% had induction chemotherapy (median 4 months), usually FOLFIRINOX (66%) or gemcitabine/nab-paclitaxel (27%). 88% received EC. Median GTV, CTV, PTVgrosstumor, and PTVelective volumes were 29 cc, 90 cc, 64 cc, and 127 cc, respectively. 16 patients (15%) had LRF after a median of 17 months (range: 2.4-30.8) from A-SMART; 13 had scans available for delineating LRF. Median follow-up from A-SMART for the entire cohort vs. LRF was 12 vs. 24 months. LRF involved the primary tumor (31%), retroperitoneal lymph nodes (25%), SMA (19%), porta hepatis (19%), and CA (6%). LRF was OOF, M, or IF in 30.8% (n = 4), 61.5% (n = 8), and 7.7% (n = 1). Distance from the 3 SMA failures to SMA origin was 10 cm (EC used), 9.3 cm (EC used), and 3 cm (no EC). The 1 CA failure involved the CA origin (no EC). Median mean, maximum, and minimum dose of the contoured LRF region on the original plan was 33.3 Gy (range: 9.7-50.3 Gy), 56 Gy (range: 44.2-71.4 Gy), and 11.4 Gy (range: 1.2-22.7 Gy), respectively. Median V20, V25, V30, V35, and V40 of the contoured LRF was 84.3% (range: 16.1-100%), 69.2% (range: 12.5-99.7%), 57.5% (range: 9.3-95.5%), 41.2% (range: 6.8-84.0%), and 32.7% (range: 4.8-71.8%).

CONCLUSION

This study represents the first patterns of LRF analysis after ablative 5-fraction SBRT for PDAC. Although EC is not currently endorsed by published pancreas SBRT guidelines, our low LRF incidence especially involving the CA/SMA demonstrates that EC should be considered, even when delivering ablative dose. Furthermore, given that nearly all LRF were M or OOF we have considered expanding our institutional elective volumes. While the optimal EC dose is uncertain, 33-35 Gy appears effective in limiting IF LRF and therefore has been standardized within ongoing ablative SBRT trials for PDAC at our institution.

The Anatomy and Evolution of a Quality Proton Therapy Plan Check Process: An Institutional Review

PURPOSE/OBJECTIVE(S)

There exists limited standard guidance from the physics community on the optimal way to ensure high-reliability proton therapy treatments. Following the guidance of AAPM MPPG 4a/4b and Task Groups 100/275, our institution has developed, implemented, and maintained strategies over the last five years to streamline workflows, enable more complex treatments, standardize procedures, and manage risk from slip or omission type errors in proton therapy. The evolution and success of that is observed from an institutional analysis of past operations data.

MATERIALS/METHODS

From the outset, standard care paths were used to sequence our workflows. These chains of tasks were well-defined and timestamped upon completion for every patient. Over five years, additional multiple interventions were implemented including clinical site standardization, checklists, root cause analysis, and failure mode identification. These were used to counter environmental variables with potential to disrupt timelines like growing patient volume, staffing demands, and new technique adoptions. These interventions went through extensive design, validation, and continuous improvement phases by the entire clinical team. Using ARIA v15.5, task timestamp data from the past 5 years were mined for physics proton-specific planning tasks and used to compute how early/late each task was in comparison to the expected due time. Average and standard deviation data were computed and used to create control charts. This coupled with the average time per year was cross-referenced with interventions to determine the impact on plan preparation timelines.

RESULTS

Over 5 years, the standard care path length reduced from 16 to 13 business days. The greatest impact on timelines was observed from standardizing clinical site guidelines. This minimized variability in task times and allowed the creation of checklists. By standardizing, we identified slack as well the need for new tasks. Overall, the average days late or early went from on-average late to on-average early (Table 1). The control charts indicate that many tasks stabilized in recent years. Furthermore, these interventions allowed us to safely increase the complexity of our proton plans using Monte Carlo dose calculations, 4D-optimization, robustness standards, repainting, and increased beams with no slippage in overall timelines.

CONCLUSION

Clinical site standardization, checklists, consistent process re-evaluation, and a team attitude of continuous improvement allowed us to improve control of our processes while simultaneously expanding treatment complexity and meeting the goals of our quality management plan.

Ablative 5-Fraction CT vs. MR-Guided Pancreatic SBRT: Evaluation of Interfraction Anatomic Changes on Dosimetric Constraints

PURPOSE/OBJECTIVE(S)

CT-guided SBRT for locally advanced pancreatic cancer (LAPC) is usually non-ablative (BED < 100 Gy10) to minimize grade 3+ toxicity risks given the concern of interfraction anatomic changes (IACs) in GI anatomy and imaging quality associated with kV-CBCT. Emerging data demonstrate that MR guidance facilitates 5-fraction (fx) dose escalation due to superior soft tissue contrast, continuous intrafraction imaging, automatic beam gating, and on-table adaptive replanning capability. Treatment outcomes for ablative 5-fx CT- vs. MR-guided SBRT are not well characterized, nor are differences in predicted GI OAR doses when accounting for IACs.

MATERIALS/METHODS

Weevaluated 40 plans (20 CT, 20 MR) for 20 LAPC patients (pts) previously treated in breath hold (BH) on a 0.35 T MR-Linac. Prescribed dose was 50 Gy (gross disease) and 33 Gy (elective) in 5 fx using a simultaneous integrated boost technique. CT plans were retrospectively created using 2-3 VMAT arcs with the same prescription dose, target volumes (assuming BH), and constraints (prioritizing OARs over target coverage) as the MR IMRT plans (∼20-40 fields). CT planners were blinded to MR plans. We compared predicted GI OAR dose of CT vs. MR plans across each of the 5 fx for all 20 patients to evaluate the dosimetric impact of IACs by coregistering CT plans to the anatomy of the day based on 0.35T MR scans acquired for GI OAR segmentation and treatment delivery.

RESULTS

MedianV100% of the GTV, CTV, PTV50, and PTV33 across the original CT vs. MR plans were 97.5% vs. 91.3% (p = 0.017), 99.9% vs. 98.2% (p<0.01), 86.2% vs. 79.3% (p = 0.39), and 97.2% vs. 93.0% (p<0.01), respectively. GI OAR constraints were met for all original CT/MR plans although it was predicted that 1+ GI OAR constraint would be violated (most commonly duodenum) for 88/100 CT vs. 85/100 MR fractions. Across the 88 violated CT fractions, the median predicted GI OAR doses were duodenum V35: 3.3 cc (range: 0.16-18.0cc), duodenum V40: 1.2 cc (range: 0.01-11.9cc), small bowel V35: 1.2 cc (range: 0.4-10.9cc), small bowel V40: 0.2 cc (range: 0.04-7.0cc), stomach V35: 1.5 cc (range: 0.52-6.8cc), stomach V40: 0.3 cc (range: 0.05-2.8cc). GI OAR doses across the 85 violated MR fractions were similar. Median fxs per pt with 1+ predicted GI OAR violation was 5 (range: 1-5) for both CT and MR plans.

CONCLUSION

This isthe first evaluation of IAC effects on predicted GI OAR dose for 5-fx CT- vs. MR-guided SBRT. Although VMAT arcs facilitated higher target coverage in the initial CT plans, GI OAR constraint violations were observed in 85-88% of CT/MR plans. Although on-table adaptive replanning is routine on MR-guided Linacs it is not commonly available on CT-guided Linacs. As such, ablative 5-fx SBRT delivered with CT guidance is expected to result in significant toxicity due to exceeding GI OAR constraints for most delivered fractions.

Characterization of Large Brain Metastases with 18F-Fluciclovine PET/CT Treated with Staged Stereotactic Radiosurgery (SSRS): Phase 1 Proof-of-Concept Interim Analysis

PURPOSE/OBJECTIVE(S)

Single-session stereotactic radiosurgery (SRS) for large brain metastases (>2cm) results in modest local control. Temporally staged SRS (SSRS), whereby 2 stages of SRS are delivered over a time interval of several weeks, is a novel strategy associated with improved control rates and acceptable radiation necrosis rates. Biomarkers for response are lacking. Here, we report interim results of a phase 1, proof-of-concept study (NCT04689048) to assess the potential clinical utility of amino acid radiotracer 18F-fluciclovine PET/CT as a functional integral biomarker for patients with large brain metastases treated with SSRS.

MATERIALS/METHODS

Patients with previously untreated large brain metastases (≥1 lesion; >2cm) underwent a baseline (pre-treatment) 18F-fluciclovine PET/CT and contrast-enhanced treatment planning brain MRI immediately before first SSRS (15 Gy), an interim PET/CT + MRI (4 weeks after the 1st SSRS, immediately prior the 2nd SSRS [15 Gy]), and post-treatment PET/CT + MRI (8 weeks after 2nd SSRS). This interim analysis reviewed the imaging characteristics from static PET images acquired 10-25 minutes after 18F-fluciclovine injection, for the first 7 enrolled patients who completed baseline imaging and 5 who completed the entire treatment course.

RESULTS

Seven patients completed baseline imaging and were treated with SSRS for 9 protocol-eligible target lesions, and an additional 25 bystander lesions were treated with SRS. The median age was 72 years and 57% were female. All lesions > 5 mm exhibited baseline increased 18F-fluciclovine uptake compared to the normal contralateral brain. The median baseline target lesion diameters and volumes were 2.16 cm (1.76-3.22 cm) and 4.71cc (2.24-10.21 cc). The median baseline SUVmax, SUVpeak, and SUVmean values were 5.78 (2.16-8.79), 3.33 (0.5-2.72), and 1.75 (1.22-5.16), respectively. The median relative reduction in diameter and volume were both 2% (-13% to 23% and -30% to 60%, respectively) at the interim scans, and at the first follow-up were 30% (-0.2% to 44%) and 43% (-13% to 94%), respectively. Corresponding median relative reduction values for SUVmax, SUVpeak, and SUVmean at interim scans were 20% (-174%-73%), 9% (-99% to 75%), and 14% (-36% to 69%), and at first follow-up 59% (21% to 87%), 41% (-11% to 86%), and 21% (-44% to 79%), respectively. Bystander lesions (< 2 cm) treated with SRS had a median baseline lesion diameter and volume of 0.5 cm (Range: 0.20-1.64 cm) and 0.06 cc (Range: 0.01-1.94 cc). Corresponding median reductions for SUVmax were 5% at interim and 63% at follow-up scans.

CONCLUSION

This proof-of-concept interim study reports baseline 18F-fluciclovine metrics for patients with brain metastases of varying lesion diameters and volumes. Target lesions appear to demonstrate interval reduction in PET metrics after SSRS, more than dimensional measurements alone.

Effects of Domestication on Plant-Microbiome Interactions

Through the process of domestication, selection is targeted on a limited number of plant traits that are typically associated with yield. As an unintended consequence, domesticated plants often perform poorly compared to their wild progenitors for a multitude of traits that were not under selection during domestication, including abiotic and biotic stress tolerance. Over the past decade, advances in sequencing technology have allowed for the rigorous characterization of host-associated microbial communities, termed the microbiome. It is now clear that nearly every conceivable plant interaction with the environment is mediated by interactions with the microbiome. For this reason, plant-microbiome interactions are an area of great promise for plant breeding and crop improvement. Here, we review the literature to assess the potential impact that domestication has had on plant-microbiome interactions and the current understanding of the genetic basis of microbiome variation to inform plant breeding efforts. Overall, we find limited evidence that domestication impacts the diversity of microbiomes, but domestication is often associated with shifts in the abundance and composition of microbial communities, including taxa of known functional significance. Moreover, genome-wide association studies and mutant analysis have not revealed a consistent set of core candidate genes or genetic pathways that confer variation in microbiomes across systems. However, such studies do implicate a consistent role for plant immunity, root traits, root and leaf exudates and cell wall integrity as key traits that control microbiome colonization and assembly. Therefore, selection on these key traits may pose the most immediate promise for enhancing plant-microbiome interactions through breeding.

Geographical Distribution of Access to Healthcare in Patients Diagnosed with Hypospadias

Objective Hypospadias is a congenital disease of unknown etiology involving multiple epigenetic, genetic, and endocrinological factors. It is a highly incapacitating condition. Its surgical management is one of the most frequent surgical procedures done by pediatric urologists. Furthermore, the geographical distribution and healthcare access is limited in Colombia. The Colombian Ministry of Health has consolidated a nationwide registry called Integrated Social Protection Information System (SISPRO, in the Spanish acronym) to collect comprehensive information on the use and frequency of resources associated with health care in Colombia. The aim of the present study was to analyze the number of cases reported between 2014 and 2018 and the geographical distribution of access to healthcare of patients with hypospadias in Colombia.

Methods An observational, retrospective study of hypospadias in Colombia, 2014–2018, was performed using data extracted from the Individual Health Records System (RIPS) in SISPRO. Satscan, version 9.6 was used to perform a distribution analysis of the georeferenced population using a Poisson model. To visualize the results, the software projected the result onto a Google Earth map.

Results Between January 2014 and December 2018, a total of 8,990 cases of hypospadias were evaluated in Colombia. The geographical distribution in the national territory has areas with high evaluation rates. On average, the departments in which the majority of cases were evaluated during the study period were Bogotá, D.C., Antioquia, and Valle del Cauca (2,196, 1,818 and 1,151 cases, respectively). The statistical analysis of the space exploration (Fig. 1) identified the area with the highest concentration of cases (red) and the areas in which the lowest number of patients was evaluated (blue). The geographical distribution showed increasing trends in areas near the center of the country, especially in the cities of Bogotá, Cali, Ibagué, and Pereira.

Conclusion There is a greater concentration of cases evaluated in the center of the country, where the cities with better access to subspecialized medical care are located. This highlights inequalities in health services and the opportunity for surgical care among regions of the country. If we consider that the prevalence rates of hypospadias remain stable, ∼ 87% of the patients with hypospadias will not be evaluated by a subspecialist.

P–059 Association between seminal levels of Fe and semen quality

Study question

The detection of metals in semen offers a new field in the study of male infertility.

Summary answer

Normozoospermia is associated with higher amounts of Fe. In males with pathological spermiogram, the percentage of men with Fe in semen was lower than expected.

What is known already

Increased levels of Fe in human semen appear to have a significant correlation with male fertility, suggesting that Fe in human seminal plasma has an important factor in male reproductive function. Fe acts as an antioxidant being a co-factor of catalasa, which protects sperm. On the other hand, elevated Fe levels are associated with sperm damage and continues to increase the lipid peroxidation that will affect the plasma membrane and the sperm motility. Most authors associate Fe with sperm motility and higher estimated fertility potential, based on standard semen parameters in fertile men, which are associated with lower levels of Fe.

Study design, size, duration

A prospective study was carried out in 102 men in a Reproduction unit in Tenerife, from February to April 2018 as a part on an epidemiologic study of environmental contaminants and male reproduction. The participant were categorized into two groups, according to the results of semen analysis following the World Health Organization guidelines: the pathological and the normal semen group that constituted the control group. The metal was determined in semen samples.

Participants/materials, setting, methods

Semen quality and levels of Fe were measured in seminal plasma on a total of 102 men attended successively, for the initial infertility evaluation, The collected samples were used for both semen analysis following the World Health Organization (WHO) guidelines and metal detection and carried out using a Makler® counting chamber (Irvine Scientific, CA) and for metals, were determined by ICP-OES (Inductively Coupled Plasma-Optical Emission Spectrometry) in semen samples.

Main results and the role of chance

The percentage of males with the presence of Fe was 97.1% and the average level were 0.6283 mg/Kg. When analyzing the relationship between the spermiogram parameters with the levels of Fe in the semen, significant differences were found. All men with a normal sperm analysis presented Fe in semen, but among men diagnosed with altered spermiogram, the percentage of men with Fe in semen (92.7%) was lower than expected (97%) (χ2 128 1 =4.59; p = 0.032). As for the concentration of Fe in spermiogram in the first quartile (25% lower), measuring 0.33 mg/Kg, more pathological samples were found than expected (X2 133 2 =6.921; p = 0.031) having a higher probability of being more pathological (52% vs 31.4%). On the other hand, men with pathological sperm concentration, have higher levels of Fe, in the fourth quartile (0.61 mg/kg), with more frequency than expected (90.6% vs 97%) (χ2 136 1 =6.48; p = 0.011). The association between BMI and the presence of Fe was statistically significant. In obese males (BMI ≥30.0 kg/m2), the percentage of men with Fe in semen (80%) was lower than expected (97%) (χ2 42 2 =11.302; p = 0.001).

Limitations, reasons for caution

The limitation of this study was the volume of semen that could be obtained for metal detection, only 0.8 mL. because the collected samples were used for both semen analysis and metal detection.

Wider implications of the findings: The determination of metals in semen opens a new field in the study of male infertility and many cases of unknown infertility could be due to metal presence or absence in semen, with the option of performing treatments.

Trial registration number

Not applicable

Bycatch mitigation of protected and threatened species in tuna purse seine and longline fisheries

Bycatch and mortality in fishing gear poses a conservation threat worldwide to many marine species. Resource managers and conservation scientists face challenges in identifying bycatch mitigation solutions that work for multiple taxa while maintaining acceptable levels of target fish catch. The most successful mitigation measures to address bycatch concerns are those that (1) minimize bycatch with limited or no impact on target species catch, (2) have been proven through at-sea experimental research, (3) are practical, affordable, and easy to use, and (4) do not risk the safety of the fishing vessel crew or the bycaught animals. We conducted a review of mitigation measures in fishing gears that target tuna and tuna-like species and that either prevent capture of non-target species in fishing gear or facilitate alive post-capture release, and evaluated these against 4 defined criteria: effective, proven, practical, and safe. This paper outlines the most effective bycatch mitigation measures, as based upon the best scientific information available, in commercial and artisanal pelagic longline and purse seine fisheries, specifically those that target tuna and tuna-like species. This review includes information on gear and operational changes to fishing practices that reduce bycatch for protected and threatened species across taxonomic groups, with a focus on cetaceans, sea turtles, seabirds, sharks, and istiophorid billfishes. The information provided can guide future research and management efforts in Regional Fisheries Management Organizations that are specific to tuna fishing and that aim to minimize impacts to protected and threatened species while maintaining viable commercial fisheries.

PRL3 enhances T-cell acute lymphoblastic leukemia growth through suppressing T-cell signaling pathways and apoptosis

T cell acute lymphoblastic leukemia (T-ALL) is an aggressive malignancy of thymocytes and is largely driven by the NOTCH/MYC pathway. Yet, additional oncogenic drivers are required for transformation. Here, we identify protein tyrosine phosphatase type 4 A3 (PRL3) as a collaborating oncogenic driver in T-ALL. PRL3 is expressed in a large fraction of primary human T-ALLs and is commonly co-amplified with MYC. PRL3 also synergized with MYC to initiate early-onset ALL in transgenic zebrafish and was required for human T-ALL growth and maintenance. Mass spectrometry phosphoproteomic analysis and mechanistic studies uncovered that PRL3 suppresses downstream T cell phosphorylation signaling pathways, including those modulated by VAV1, and subsequently suppresses apoptosis in leukemia cells. Taken together, our studies have identified new roles for PRL3 as a collaborating oncogenic driver in human T-ALL and suggest that therapeutic targeting of the PRL3 phosphatase will likely be a useful treatment strategy for T-ALL.

How does gatekeeper training improve suicide prevention for elderly people in nursing homes? A controlled study in 24 centres

Background

The death rate due to suicide in elderly people is particularly high. As part of suicide selective prevention measures for at-risk populations, the WHO recommends training “gatekeepers”.

Methods

In order to assess the impact of gatekeeper training for members of staff, we carried out a controlled quasi-experimental study over the course of one year, comparing 12 nursing homes where at least 30% of the staff had undergone gatekeeper training with 12 nursing homes without trained staff. We collected data about the residents considered to be suicidal, their management further to being identified, as well as measures taken at nursing home level to prevent suicide.

Results

The two nursing home groups did not present significantly different characteristics. In the nursing homes with trained staff, the staff were deemed to be better prepared to approach suicidal individuals. The detection of suicidal residents relied more on the whole staff and less on the psychologist alone when compared to nursing homes without trained staff. A significantly larger number of measures were taken to manage suicidal residents in the trained nursing homes. Suicidal residents were more frequently referred to the psychologist. Trained nursing homes put in place significantly more suicide prevention measures at an institutional level.

Conclusions

Having trained gatekeepers has an impact not only for the trained individuals but also for the whole institution where they work, both in terms of managing suicidal residents and routine suicide prevention measures.

Pesticide Misting System Enhances Residual Pesticide Treatment of HESCO Geotextile

Residual pesticide treatment of US military materials such as camouflage netting and HESCO blast wall geotextile is an effective way to reduce biting pressure within protected perimeters. However, residual treatments eventually wane and require retreatment in situ, which may not be possible or practical in military scenarios. One solution is to install pesticide misting systems on treated perimeters, which may additively enhance residual treatments, and gradually retreat perimeter material as misted pesticide settles. In this investigation we show that pesticide misting can extend efficacy of residual treatments on HESCO geotextile against mosquitoes and sand flies in a hot-arid desert environment by 1-2 wk.

Transfluthrin Spatial Repellent on US Military Materials Reduces Culex tarsalis Incursion in a Desert Environment

Standard residual pesticides applied to US military materials such as camouflage netting can reduce mosquito biting pressure in the field but may contribute to the evolution of resistance. However, residual applications of a spatial repellent such as transfluthrin could allow mosquitoes the opportunity to escape, only inducing mortality if insects linger, for example after becoming trapped in a treated tent. In this study we investigated the capability of transfluthrin on 2 types of US military material to reduce natural populations of disease vector mosquitoes in a cool-arid desert field environment in southern California. We found that transfluthrin could reduce Culex tarsalis incursion into protected areas by up to 100% upon initial treatment and up to 45% for at least 16 days posttreatment, showing that this compound could be an effective element in the US Department of Defense integrated vector management system appropriate for further study.