DOTATATE PET/MR Imaging Differentiates Secondary-Progressive from de Novo World Health Organization Grade 3 Meningiomas

BACKGROUND AND PURPOSE

WHO grade 3 meningiomas are rare and poorly understood and have a higher propensity for recurrence, metastasis, and worsened clinical outcomes compared with lower-grade meningiomas. The purpose of our study was to prospectively evaluate the molecular profile, PET characteristics, and outcomes of patients with World Health Organization grade 3 meningiomas who were imaged with gallium 68 (68Ga) DOTATATE PET/MR imaging.

MATERIALS AND METHODS

Patients with World Health Organization grade 3 meningiomas enrolled in our prospective observational cohort evaluating the utility of (68Ga) DOTATATE PET/MR imaging in somatostatin receptor positive brain tumors were included. We stratified patients by de novo-versus-secondary-progressive status and evaluated the differences in the PET standard uptake value, molecular profiles, and clinical outcomes.

RESULTS

Patients met the inclusion criteria (secondary-progressive: 7/14; de novo: 7/14). The secondary-progressive cohort had a significantly higher per-patient number of surgeries (4.1 versus 1.6; P = .011) and trended toward a higher number of radiation therapy courses (2.4 versus 1.6; P = .23) and cumulative radiation therapy doses (106Gy versus 68.3Gy; P = .31). The secondary-progressive cohort had a significantly lower progression-free survival compared with the de novo cohort (4.8 versus 37.7 months; P = .004). Secondary-progressive tumors had distinct molecular pathology profiles with higher numbers of mutations (3.5 versus 1.2; P = .024). Secondary-progressive tumors demonstrated higher PET standard uptake values (17.1 versus 12.4; P = .0021).

CONCLUSIONS

Our study confirms prior work illustrating distinct clinical outcomes in secondary-progressive and de novo World Health Organization grade 3 meningiomas. Furthermore, our findings support (68Ga) DOTATATE PET/MR imaging as a useful management strategy in World Health Organization grade 3 meningiomas and provide insight into meningioma biology, as well as clinical management implications.

Improving Patient Compliance for More Efficient Deep Inspiration Breath Hold Treatment through Innovation and Education

PURPOSE/OBJECTIVE(S)

Visual guidance has been widely proven to improve the reproducibility and stability of Deep Inspiration Breath Hold (DIBH) treatments. Here, we present a quality improvement project by implementing the use of visual guidance in a multi-campus institution to improve clinical efficiency, including the design of a novel mount for the visual aid and the creation of a patient education video to better prepare lung and GI patients for their DIBH treatments.

MATERIALS/METHODS

Prior to institution-wide implementation, the clinical feasibility of utilizing visual guidance for DIBH treatments was determined by a pilot study with 10 lung/GI patients. A commercial visual guidance device was used, which consisted of a tablet-like device, attached to a mount affixed to the treatment couch. The device is positioned over the patient's head, displaying the real-time vertical motion of a block with infrared markers on the patient's abdomen. The original mount for the device locks onto the superior end of the treatment couch, which occupies space used for immobilization devices and limits the number of patients eligible for visual guidance when the isocenter is inferior, as for GI patients. A novel in-house mount was designed to overcome this limitation. Also, a patient education video was created to introduce the concept of DIBH and the visual aid device. Visual guidance is offered at the first treatment; its use is optional, and patients may start or stop using it at any time. If the device is not used, the patient relies on audio coaching from the radiation therapists (RTTs), which is the standard practice in our clinic.

RESULTS

All 10 patients in the pilot who were offered the visual aid used it, found it helpful and continued to use it throughout their treatment, with no issues reported. The median number of fractions for all 10 patients was 5(3-15). The in-house mount was manufactured from 3D printed and machined components. The treatment couch was 3D scanned, and the mount was designed to clamp laterally on the couch top and align with the indexing indentations. The in-house mount is easy to use and is more versatile than the commercial mount, enabling use for patients with inferior isocenters. Prior to treatment, patients were encouraged to view the <3 min long patient education video that consisted of a combination of animation and real-actor content. Verbal instructions for use were also given by RTTs at the first treatment. Upon successful completion of the pilot study, the use of visual guidance was implemented institution-wide across 5 campuses for all lung and GI DIBH patients, being utilized on an average of 14 patients/week.

CONCLUSION

A quality improvement project was developed and successfully implemented to introduce the use of visual guidance for lung and GI DIBH patients at a large institution, improving the efficiency of DIBH treatment for both the patients and RTTs.

Progression-Free Survival in Patients with WHO-2 Meningioma Undergoing Active Surveillance Based on DOTATATE PET Evidence of Gross Total Resection: Prospective Observational Study

PURPOSE/OBJECTIVE(S)

MRI is the standard of care for meningioma radiotherapy planning, but lacks sensitivity for postoperative small volume disease and osseous or parenchymal invasion. NRG-BN003 (NCT03180268) randomizes patients with WHO-2 meningiomas and MRI-determined gross total resection (GTR) to observation or 60 Gy IMRT to the resection bed. More sensitive and specific imaging biomarkers than MRI may improve clinical outcomes in meningioma by limiting unnecessary irradiation of normal tissues and improving radiotherapy targeting. [68Ga]-DOTATATE, a PET radiotracer targeting somatostatin receptor 2 (SSTR2) is a highly sensitive and specific meningioma biomarker. Our dedicated DOTATATE brain PET/MRI and PET/CT protocol allows meningioma differentiation from post-treatment change, using SUV analysis and Patlak modeling. Our prospective IRB-approved observational trial (NCT04081701) has imaged >100 patients with meningioma. In the sub-analysis presented here, we prospectively evaluated PFS in patients with WHO-2 tumors and postoperative GTR as determined by [68Ga]-DOTATATE brain PET/MRI or PET/CT who were managed solely with active surveillance. We hypothesized that the PFS of patients with GTR by PET managed with active surveillance would be higher than reported PFS data for patients with MRI-determined GTR, using NRG-BN003's observation arm (randomized trial comparing observation to fractionated RT) as a reference standard.

MATERIALS/METHODS

From the cohort of >100 patients with SSTR2-positive brain neoplasms enrolled between 9/2019 and 10/2022 and imaged according to our previously published protocol, a sub-cohort of patients were selected with WHO-2 meningioma, postoperative findings of GTR, and postoperative active surveillance with periodic MRI every 3-6 months. Kaplan-Meier survival analysis was performed.

RESULTS

A total of 12 patients met inclusion criteria. Mean patient age was 64 years and 5 (42%) were female. Mean follow up period was 23.4 months (range: 7-38). 83% (10/12) patients underwent postoperative PET/MRI and 17% (2/12) underwent PET/CT. 2 patients (17%) progressed, at 22 and 34 months, respectively; the remainder remain progression-free. Both patients who had progression were successfully salvaged with focal fractionated radiosurgery. Kaplan-Meier analysis demonstrated PFS at almost 3 years to be 75%, which is substantially higher than the reported 3-year PFS of 60% in the literature. Overall survival was 100%.

CONCLUSION

[68Ga]-DOTATATE PET can improve the specificity of imaging-based assessment of the extent of resection of WHO-2 meningiomas, thereby improving clinical outcomes. In this cohort of patients with completely resected WHO-2 meningiomas (as assessed by postoperative gadolinium-enhanced MRI and DOTATATE PET) who are conservatively managed, recurrences have been rare and amenable to radiosurgical salvage.

Cost-Effectiveness Analysis of 68Ga-DOTATATE PET/MRI in Radiotherapy Planning in Patients with Intermediate-Risk Meningioma

BACKGROUND AND PURPOSE

While contrast-enhanced MR imaging is the criterion standard in meningioma diagnosis and treatment response assessment, gallium 68Ga-DOTATATE PET/MR imaging has increasingly demonstrated utility in meningioma diagnosis and management. Integrating 68Ga-DOTATATE PET/MR imaging in postsurgical radiation planning reduces the planning target volume and organ-at-risk dose. However, 68Ga-DOTATATE PET/MR imaging is not widely implemented in clinical practice due to higher perceived costs. Our study analyzes the cost-effectiveness of 68Ga-DOTATATE PET/MR imaging for postresection radiation therapy planning in patients with intermediate-risk meningioma.

MATERIALS AND METHODS

We developed a decision-analytical model based on both recommended guidelines on meningioma management and our institutional experience. Markov models were implemented to estimate quality-adjusted life-years (QALY). Cost-effectiveness analyses with willingness-to-pay thresholds of $50,000/QALY and $100,000/QALY were performed from a societal perspective. Sensitivity analyses were conducted to validate the results. Model input values were based on published literature.

RESULTS

The cost-effectiveness results demonstrated that 68Ga-DOTATATE PET/MR imaging yields higher QALY (5.47 versus 5.05) at a higher cost ($404,260 versus $395,535) compared with MR imaging alone. The incremental cost-effectiveness ratio analysis determined that 68Ga-DOTATATE PET/MR imaging is cost-effective at a willingness to pay of $50,000/QALY and $100,000/QALY. Furthermore, sensitivity analyses showed that 68Ga-DOTATATE PET/MR imaging is cost-effective at $50,000/QALY ($100,000/QALY) for specificity and sensitivity values above 76% (58%) and 53% (44%), respectively.

CONCLUSIONS

68Ga-DOTATATE PET/MR imaging as an adjunct imaging technique is cost-effective in postoperative treatment planning in patients with meningiomas. Most important, the model results show that the sensitivity and specificity cost-effective thresholds of 68Ga-DOTATATE PET/MR imaging could be attained in clinical practice.

[68 Ga]-DOTATATE PET/MR-based evaluation of physiologic somatostatin receptor 2 expression in the adult pituitary gland as a function of age and sex in a prospective cohort

PURPOSE

The pituitary gland has the fourth highest physiologic avidity of [68 Ga]-DOTATATE. In order to guide our understanding of [68 Ga]-DOTATATE PET in clinical contexts, accurate characterization of the normal pituitary gland is first required. This study aimed to characterize the normal pituitary gland using dedicated brain [68 Ga]-DOTATATE PET/MRI as a function of age and sex.

METHODS

A total of 95 patients with a normal pituitary gland underwent brain [68 Ga]-DOTATATE PET examinations for the purpose of diagnosing CNS SSTR2 positive tumors (mean age: 58.9, 73% female). Maximum SUV of the pituitary gland was obtained in each patient. SUV of superior sagittal sinus was obtained to calculate normalized SUV score (SUVR) of the gland. The anatomic size of the gland was collected as maximum sagittal height (MSH). Correlations with age and sex were analyzed.

RESULTS

The mean SUV and SUVR of the pituitary gland were 17.6 (range: 7-59.5, SD = 7.1) and 13.8 (range: 3.3-52.6, SD = 7.2), respectively. Older females had significantly higher SUV of the pituitary gland compared to younger females. When stratified by age and sex, both older and younger females had significantly higher pituitary SUV than older males. SUVR did not differ significantly by age or sex. MSH of the pituitary gland in younger females was significantly greater than in younger males at all age cutoffs.

CONCLUSION

This study provides an empiric profiling of the physiological [68 Ga]-DOTATATE avidity of the pituitary gland. The findings suggest that SUV may vary by age and sex and can help guide the use of [68 Ga]-DOTATATE PET/MRI in clinical and research settings. Future studies can build on these findings to investigate further the relationship between pituitary biology and demographic factors.

Association between atherogenic lipids and GnRH agonists for prostate cancer in men with T2DM: a nationwide, population-based cohort study in Sweden

BACKGROUND

Gonadotropin-releasing hormone agonists (GnRH) used in prostate cancer (PCa) are associated with atherogenic dyslipidaemia. It can be assumed that GnRH need to be used with greater caution in men with type 2 diabetes mellitus (T2DM). This study investigated association of GnRH with atherogenic lipids (AL) in PCa men with T2DM.

METHODS

Two cohorts including 38,311 men with 11 years follow-up based on Swedish national registers were defined (PCa-Exposure cohort and GnRH-Exposure cohort). Based on European guidelines on cardiovascular diseases (CVD), primary outcomes were defined as: 1.0 mmol/L increase in AL and lipid-lowering therapy (LLT) intensification. We used Cox proportional-hazards models and Kaplan-Meier curves to assess the association.

RESULTS

There was an association between GnRH and increased AL (i.e., triglyceride, PCa-Exposure cohort: HR 1.77, 95% CI 1.48-2.10; GnRH-Exposure cohort: HR 1.88, 95% CI 1.38-2.57). There was also an association between PCa diagnosis and increased AL. In contrast, no association between LLT intensification and GnRH was found.

CONCLUSION

In this large population-based study, men with T2DM on GnRH for PCa had an increased risk of increased atherogenic lipids. These results highlight the need to closely monitor lipids and to be ready to intensify lipid-lowering therapy in men with T2DM on GnRH for PCa.

The KNee OsteoArthritis Prediction (KNOAP2020) challenge: An image analysis challenge to predict incident symptomatic radiographic knee osteoarthritis from MRI and X-ray images

OBJECTIVES

The KNee OsteoArthritis Prediction (KNOAP2020) challenge was organized to objectively compare methods for the prediction of incident symptomatic radiographic knee osteoarthritis within 78 months on a test set with blinded ground truth.

DESIGN

The challenge participants were free to use any available data sources to train their models. A test set of 423 knees from the Prevention of Knee Osteoarthritis in Overweight Females (PROOF) study consisting of magnetic resonance imaging (MRI) and X-ray image data along with clinical risk factors at baseline was made available to all challenge participants. The ground truth outcomes, i.e., which knees developed incident symptomatic radiographic knee osteoarthritis (according to the combined ACR criteria) within 78 months, were not provided to the participants. To assess the performance of the submitted models, we used the area under the receiver operating characteristic curve (ROCAUC) and balanced accuracy (BACC).

RESULTS

Seven teams submitted 23 entries in total. A majority of the algorithms were trained on data from the Osteoarthritis Initiative. The model with the highest ROCAUC (0.64 (95% confidence interval (CI): 0.57-0.70)) used deep learning to extract information from X-ray images combined with clinical variables. The model with the highest BACC (0.59 (95% CI: 0.52-0.65)) ensembled three different models that used automatically extracted X-ray and MRI features along with clinical variables.

CONCLUSION

The KNOAP2020 challenge established a benchmark for predicting incident symptomatic radiographic knee osteoarthritis. Accurate prediction of incident symptomatic radiographic knee osteoarthritis is a complex and still unsolved problem requiring additional investigation.

High-Resolution T2-Weighted Imaging for Surveillance in Postoperative Vestibular Schwannoma: Equivalence with Contrast-Enhanced T1WI for Measurement and Surveillance of Residual Tumor

BACKGROUND AND PURPOSE

Patients with surgically resected vestibular schwannoma will undergo multiple postoperative surveillance examinations, typically including postcontrast sequences. The purpose of this study was to compare high-resolution T2WI with gadolinium T1WI in the postoperative assessment of vestibular schwannoma.

MATERIALS AND METHODS

This was a retrospective study of patients with a history of resected vestibular schwannoma at a single institution. High-resolution T2WI and gadolinium T1WI were independently evaluated for residual disease. In addition, 3D and 2D measurements were performed in the group of patients with residual tumor. Statistical analysis was performed to evaluate the agreement between sequences on the binary assessment (presence/absence of tumor on initial postoperative examination) and to evaluate the equivalence of measurements for the 2 sequences on 3D and 2D quantitative assessment in individuals with residual disease.

RESULTS

One hundred forty-eight patients with retrosigmoid-approach resection of vestibular schwannomas were included in the final analysis. There was moderate-to-substantial agreement between the 2 sequences for the evaluation of the presence versus absence of tumor (Cohen κ coefficient = 0.78; 95% CI, 0.68-0.88). The 2 sequences were significantly equivalent for 2D and 3D quantitative assessments (short-axis P value = .021; long-axis P value = .015; 3D P value = .039).

CONCLUSIONS

In this retrospective study, we demonstrate moderate-to-substantial agreement in the categoric assessment for the presence versus absence of tumor and equivalence between the 2 sequences for both 2D and volumetric tumor measurements as performed in the subset of patients with measurable residual. On the basis of these results, high-resolution T2WI alone may be sufficient for early postoperative imaging surveillance in this patient population.

NIMG-92. DOTATATE PET/MR-GUIDED POSTOPERATIVE RADIOTHERAPY IN SUBTOTALLY RESECTED WHO-2 MENINGIOMA: EVALUATION OF PROGRESSION-FREE SURVIVAL IN A PROSPECTIVE COHORT

BACKGROUND

Current postoperative management recommendations for meningioma lack Level 1 evidence. NRG-0539 (NCT00895622) treated recurrent WHO-1 and newly diagnosed and completely resected (by postoperative MRI) WHO-2 meningiomas with postoperative fractionated radiotherapy to 54 Gy, but 3 year PFS remained below 60%. MRI, the standard of care (SOC) for meningioma radiotherapy planning, lacks sensitivity for postoperative small volume disease and osseous or parenchymal invasion. More sensitive and specific imaging biomarkers are needed to improve RT guidance and thereby clinical outcomes in meningioma. [68Ga]-DOTATATE is a PET radiotracer targeting somatostatin receptor 2 (SSTR2), a highly sensitive and specific meningioma biomarker. We developed a dedicated DOTATATE brain PET/MRI protocol allowing meningioma differentiation from post-treatment change, using SUV analysis and Patlak modeling. Our prospective observational trial (NCT04081701) has imaged over 90 patients with meningioma. This IRB-approved study evaluated PFS in patients with WHO-2 tumors who did not achieve GTR by [68Ga]-DOTATATE PET/MRI, managed with PET/MR guided RT, hypothesizing that the PFS of patients with STR by PET/MRI managed with PET/MR guided RT would be higher than for comparable patients enrolled on NRG 0539.

METHODS

92 patients with SSTR2-positive brain neoplasms were enrolled between 9/2019 and 5/2022 and imaged according to our previously published protocol. 7 patients met inclusion criteria (WHO-2 meningioma; postoperative PET/MR with residual activity) who underwent PET/MR-guided RT, followed with SOC MRI. Kaplan-Meier survival analysis was performed.

RESULTS

5/7 subjects (71%) were women; the mean age was 50.7 years. MRI follow-up data were available for a mean of 18.7 months (range: 16-24 months). All patients remain progression-free at this time; Kaplan-Meier analysis demonstrated 2-year PFS to be 100%, which is substantially higher than reported PFS in this clinical population using standard-of-care MRI-guided RT.

CONCLUSIONS

[68Ga]-DOTATATE PET/MR-guidance can improve PFS following postoperative RT in subtotally resected WHO-2 meningiomas.

NIMG-91. DOTATATE PET/MR-GUIDED POSTOPERATIVE MANAGEMENT IN WHO-2 MENINGIOMA: ACTIVE SURVEILLANCE BASED ON PET/MR EVIDENCE OF GROSS TOTAL RESECTION

BACKGROUND

MRI, the standard of care (SOC) for meningioma radiotherapy planning, lacks sensitivity for postoperative small volume disease and osseous or parenchymal invasion. BN003 (NCT03180268) randomizes patients with WHO-2 meningiomas and MRI-determined GTR to observation or 60 Gy IMRT to the resection bed. More sensitive and specific imaging biomarkers may improve clinical outcomes in meningioma by limiting unnecessary radiation of normal tissues and improving radiation targeting. [68Ga]-DOTATATE is a PET radiotracer targeting somatostatin receptor 2 (SSTR2), a highly sensitive and specific meningioma biomarker. We developed a dedicated DOTATATE brain PET/MRI protocol allowing meningioma differentiation from post-treatment change, using SUV analysis and Patlak modeling. Our prospective observational trial (NCT04081701) has imaged over 90 patients with meningioma. This IRB-approved study evaluated PFS in patients with WHO-2 tumors and postoperative GTR by [68Ga]-DOTATATE PET/MRI who were managed solely with active surveillance. We hypothesized that the PFS of patients with GTR by PET/MRI managed with active surveillance would be higher than for patients with MRI-determined GTR, using NRG-BN003’s observation arm (randomized trial comparing observation to fractionated radiotherapy) as a reference standard.

METHODS

92 patients with SSTR2-positive brain neoplasms were enrolled between 9/2019 and 5/2022 and imaged according to our previously published protocol. 8 patients met inclusion criteria (WHO-2 meningioma & postoperative PET/MR GTR) and were followed with SOC MRI. Kaplan-Meier survival analysis was performed.

RESULTS

5/8 subjects (62.5%) were women; the mean age was 67 years. MRI follow-up data were available for a mean of 19.75 months (range: 7-38 months). One subject (12.5%) progressed at 21 months; the remainder remain progression-free. Kaplan-Meier analysis demonstrated 3-year PFS to be 80%, which is substantially higher than the reported 3-year PFS of 69% in the literature.

CONCLUSIONS

[68Ga]-DOTATATE PET can improve the specificity of imaging-based assessment of the extent of resection of WHO-2 meningiomas.

Thrombospondin 2 is a Functional Predictive and Prognostic Biomarker for Triple-Negative Breast Cancer Patients With Neoadjuvant Chemotherapy

Background: Triple-negative breast cancer (TNBC) is characterized by a more aggressive biological behavior and unfavorable outcome. Circulating and histological expression of THBS2 has been demonstrated to be a novel diagnostic and prognostic biomarker in patients with various types of tumors. However, few studies have evaluated the predictive and prognostic value of THBS2 in TNBC specifically.

Methods: In total, 185 triple-negative breast cancer patients (TNBC) with preoperative neoadjuvant chemotherapy were enrolled in this study. Serum THBS2 (sTHBS2) level was measured both prior to the start of NAC and at surgery by enzyme-linked immunosorbent assay (ELISA). Histological THBS2 (hTHBS2) expression in patients with residual tumors was evaluated by immunohistochemistry (IHC) staining method. Correlations between variables and treatment response were studied. Kaplan-Meier plots and Cox proportional hazard regression model were applied for survival analysis. Functional activities of THBS2 in TNBC cells were determined by CCK-8 assay, colony formation, wound healing, and transwell assay.

Results: Of the 185 patients, 48 (25.9%) achieved pathological complete response (pCR) after completion of NAC. Elevated pCR rates were observed in patients with a lower level of sTHBS2 at surgery and higher level of sTHBS2 change (OR = 0.88, 95%CI: 0.79–0.98, p = 0.020 and OR = 1.12, 95%CI: 1.02–1.23, p = 0.015, respectively). In survival analysis, hTHBS2 expression in residual tumor was of independent prognostic value for both disease-free survival (HR = 2.21, 95%CI = 1.24–3.94, p = 0.007) and overall survival (HR = 2.07, 95%CI = 1.09–3.92, p = 0.026). For functional studies, THBS2 was indicated to inhibit proliferation, migration, and invasion abilities of TNBC cells in vitro.

Conclusion: Our findings confirmed the value of serum THBS2 level to predict pCR for TNBC patients and the prognostic performance of histological THBS2 expression in non-pCR responders after NAC. THBS2 might serve as a promising functional biomarker for patients with triple-negative breast cancer.

SPIN-02 LEVERAGING AN MRI-GUIDED LINEAR ACCELERATOR PLATFORM FOR POST-OPERATIVE STEREOTACTIC BODY RADIATION THERAPY (SBRT) OF SPINAL METASTASES

PURPOSE/OBJECTIVE(S)

Post-operative spine SBRT presents unique clinical challenges. Spinal hardware produces CT and high-field strength MRI artifacts that obscure visualization of the spinal cord and unresected disease. Existing workflows incorporate additional invasive procedures with CT myelogram and quality control for these procedures can introduce uncertainty into SBRT planning. Reducing metallic imaging artifact with a low-field strength (0.35 T) MRI integrated into a MR-Linac (MRL) may facilitate superior visualization of the spinal cord, improved target delineation and treatment localization. The primary objective is to determine the feasibility of MRL-based simulation workflow to facilitate MR-guided post-operative spine SBRT without the need for CT myelogram or CT-based target delineation.

MATERIALS/METHODS

A single-institution, single-arm interventional feasibility study is planned. A total of 10 patients who underwent surgical resection of solid tumor spinal metastases with an indication for post-operative SBRT will be enrolled and undergo radiation planning and treatment on a MRL platform that combines a 6MV Linac and 0.35 T on-board MRI system. Enrolled subjects will undergo CT and MR simulation followed by standard-of-care post-operative spine SBRT and follow-up spine imaging every 3 months.

RESULTS

The primary endpoint is feasibility of MR-guided post-operative spine SBRT without CT myelogram. Feasibility is defined as > 70% of participants with clinically acceptable visualization/delineation as determined by blinded dual neuroradiologist review for clinically acceptable visualization/delineation of organs-at-risk (OARs) and target volume(s). Exploratory endpoints involve radiation dosimetry analysis of OARs and target volumes as well as documenting the use of adaptive planning. Radiation site progression-free survival will be recorded at 6-months after SBRT.

CONCLUSION

If feasible, an MRL-based workflow for post-operative spine SBRT represents a patient-centric approach to improve efficiency, minimize treatment delays, and avoid invasive procedures that may improve clinical management of solid tumor spinal metastases.

Association of Gonadotropin-Releasing Hormone Agonists for Prostate Cancer With Cardiovascular Disease Risk and Hypertension in Men With Diabetes

IMPORTANCE

Men with type 2 diabetes have an increased risk of cardiovascular disease (CVD). Meanwhile, gonadotropin-releasing hormone (GnRH) agonists used in prostate cancer (PCa) are associated with increased risk of CVD.

OBJECTIVE

To evaluate the association between GnRH agonist use, PCa diagnosis per se, and CVD risk in men with type 2 diabetes.

DESIGN, SETTING, AND PARTICIPANTS

This nationwide population-based cohort study identified men with type 2 diabetes by use of data in the Prostate Cancer Data Base Sweden version 4.1 and the Swedish National Diabetes Register, with longitudinal data from 2006 to 2016. These data were used to create 2 cohorts, 1 including men with and without PCa and the other including men with PCa who received and did not receive GnRH agonists. Data analysis was conducted from January 2006 to December 2016.

EXPOSURES

Treatment with GnRH agonists and PCa diagnosis were the primary exposures.

MAIN OUTCOMES AND MEASURES

Primary outcome was a 10% increase in predicted 5-year CVD risk score. Secondary outcome was worsening hypertension as defined by the European Society of Hypertension Guidelines. Cox proportional hazards regression models were used to analyze the association.

RESULTS

The PCa exposure cohort included 5714 men (median [IQR] age, 72.0 [11.0]), and the non-PCa cohort included 28 445 men without PCa (median [IQR] age, 72.0 [11.0]). The GnRH agonist-exposure cohort included 692 men with PCa who received a GnRH agonist, compared with 3460 men with PCa who did not receive a GnRH agonist. Men with PCa receiving GnRH agonists had an increased estimated 5-year CVD risk score compared with men without PCa (hazard ratio [HR], 1.25; 95% CI, 1.16-1.36) and compared with men with PCa not receiving GnRH agonists (HR, 1.53; 95% CI, 1.35-1.74). Men receiving GnRH agonists had decreased blood pressure compared with men without PCa (HR, 0.70; 95% CI, 0.61-0.80) and compared with men with PCa not receiving GnRH agonists (HR, 0.68; 95% CI, 0.56-0.82).

CONCLUSIONS AND RELEVANCE

In this population-based cohort study, there was an increased risk of CVD in men with type 2 diabetes who received a GnRH agonist for PCa. These findings highlight the need to closely control CVD risk factors in men with type 2 diabetes treated with GnRH agonists. The association between GnRH agonist use and decreased blood pressure levels warrants further study.

Incomplete circle of Willis variants and stroke outcome

BACKGROUND

There is considerable variation in circle of Willis morphology among the general population, and these variations have been correlated with risk of aneurysms, cerebral ischemia, and other clinical events.

PURPOSE

To investigate the relationship between circle of Willis variants and stroke outcome.

MATERIALS AND METHODS

We performed a retrospective study involving 297 patients from our institution's acute stroke academic registry. All received MRA examinations of the head upon admission for acute strokes. All imaging was reviewed to assess for circle of Willis variants (particularly A1 and P1 aplasia or hypoplasia) along with vertebral artery aplasia or hypoplasia. Stroke outcome was defined as good (walking independently at the time of discharge) or poor (inability to walk at discharge, assistance needed to walk at discharge, or death). Severity of stroke was assessed using the National Institute of Health Stroke Scale.

RESULTS

An incomplete circle of Willis was seen in 34% of subjects. There was no significant association between age, gender, hypertension, or presence of arterial stenosis and circle of Willis completeness. Using logistic regression, we found that the presence of an incomplete circle of Willis decreased the odds of a stroke patient having a good outcome by 47% (p = 0.046, OR 0.53, 95% CI 0.281-0.988), after adjusting for age and severity of stroke at admission.

CONCLUSION

This study suggests that an incomplete circle of Willis may be associated with a poorer prognosis for stroke patients.

Precise Measurement of the Thickness of Vaginal Intraepithelial Neoplasia

OBJECTIVES

Although carbon dioxide laser vaporization is frequently used for treating vaginal intraepithelial neoplasia (VaIN), the optimal depth of epithelial destruction with laser vaporization requires elucidation. We aimed to evaluate VaIN depth and better illustrate epithelial destruction during laser vaporization.

MATERIALS AND METHODS

We included 246 women diagnosed with VaIN (low-grade VaIN [VaIN 1], 123 women; high-grade VaIN [VaIN 2/3], 123 women) using colposcopy-directed biopsy at our hospital from January 1, 2019, to April 30, 2020. The thickness of the noninvolved epithelium, if available, was determined. All available data, including cytology and histological information, were recorded. The t test and Pearson χ 2 test were used for statistical analysis. Statistical significance was set at p < .05.

RESULTS

The involved epithelial thicknesses in VaIN 2/3 and VaIN 1 were 0.41 ± 0.21 and 0.40 ± 0.19 mm, respectively, which were both greater than their noninvolved epithelial thickness values (0.17 ± 0.10 and 0.17 ± 0.08 mm, p < .01 and p < .01, respectively). In subgroup comparisons between the VaIN 2/3 and VaIN 1 groups, the involved epithelial thickness did not differ between premenopausal patients, postmenopausal women receiving estrogen, and postmenopausal women who did not receive estrogen ( p > .05). In the VaIN 2/3 group, the lesion thickness in premenopausal was greater than that in postmenopausal women receiving estrogen ( p = .016) and those who were not receiving estrogen ( p = .017).

CONCLUSIONS

The thickness of VaIN is generally less than 1 mm for women of all ages, except in rare cases of visible lesions with papillary hyperplasia.

Changes in community and hospital-based health care use during the COVID-19 pandemic for adults with and without intellectual and developmental disabilities

BACKGROUND

Due to the functional, cognitive and communication impairments associated with intellectual and/or developmental disabilities (IDD), adaptations to service delivery during the COVID-19 pandemic may impact people with IDD differently than others. For community and hospital-based services, this study describes the proportion of adults with and without IDD who used health care in the year pre-COVID-19 and the first year of the pandemic.

METHODS

This retrospective cohort study used linked health administrative databases to identify adults aged 18-105 years with and without IDD using unique encoded identifiers. Counts and proportions of adults who used health care services were reported for the pre-COVID-19 year (16 March 2019 to 14 March 2020) and the first COVID-19 year (15 March 2020 to 15 March 2021).

RESULTS

Across services, the proportion of adults who used services was lower during the first COVID-19 year compared with the year prior, except for virtual physician visits that increased markedly for people with and without IDD. While the proportion of adults who used services was higher for those with IDD compared with those without IDD for both years, differences were greatest for mental health emergency visits and hospitalisations; adults with IDD were 6.3 to 10.9 times more likely to use these services than others with no IDD during the pandemic.

CONCLUSIONS

During the first COVID-19 year in Ontario, Canada, service use decreased for all service types, except for virtual physician visits. In both years, adults with IDD remained more likely to use services than other adults, with the largest differences in use of mental health hospitalisations and mental health emergency department visits.

Prognostic Factors of Stroke-Like Migraine Attacks after Radiation Therapy (SMART) Syndrome

BACKGROUND AND PURPOSE

Prognostic factors of stroke-like migraine attacks after radiation therapy (SMART) syndrome have not been fully explored. This study aimed to assess clinical and imaging features to predict the clinical outcome of SMART syndrome.

MATERIALS AND METHODS

We retrospectively reviewed the clinical manifestations and imaging findings of 20 patients with SMART syndrome (median age, 48 years; 5 women) from January 2016 to January 2020 at 4 medical centers. Patient demographics and MR imaging features at the time of diagnosis were reviewed. This cohort was divided into 2 groups based on the degree of clinical improvement (completely versus incompletely recovered). The numeric and categoric variables were compared as appropriate.

RESULTS

There were statistically significant differences between the completely recovered group (n = 11; median age, 44 years; 2 women) and the incompletely recovered group (n = 9; median age, 55 years; 3 women) in age, months of follow-up, and the presence of steroid treatment at diagnosis (P = .028, .002, and .01, respectively). Regarding MR imaging features, there were statistically significant differences in the presence of linear subcortical WM susceptibility abnormality, restricted diffusion, and subcortical WM edematous changes in the acute SMART region (3/11 versus 8/9, P = .01; 0/11 versus 4/9, P = .026; and 2/11 versus 7/9, P = .022, respectively). Follow-up MRIs showed persistent susceptibility abnormality (11/11) and subcortical WM edematous changes (9/9), with resolution of restricted diffusion (4/4).

CONCLUSIONS

Age, use of steroid treatment at the diagnosis of SMART syndrome, and MR imaging findings of abnormal susceptibility signal, restricted diffusion, and subcortical WM change in the acute SMART region can be prognostic factors in SMART syndrome.

Dynamic 68Ga-DOTATATE PET/MRI in the Diagnosis and Management of Intracranial Meningiomas

Purpose To evaluate dynamic gallium 68 (⁶⁸Ga) tetraazacyclododecane tetraacetic acid octreotate (DOTATATE) brain PET/MRI as an adjunct modality in meningioma, enabling multiparametric standardized uptake value (SUV) and Patlak net binding rate constant (K_i) imaging, and to optimize static acquisition period. Materials and Methods In this prospective study (ClinicalTrials.gov no. NCT04081701, DOMINO-START), ⁶⁸Ga-DOTATATE PET/MRI-derived time-activity curves (TACs) were measured in 84 volumes of interest in 19 participants (mean age, 63 years; range, 36-89 years; 13 women; 2019-2021) with meningiomas. Region- and voxel-specific K_i were determined using Patlak analysis with a validated population-based reference tissue TAC model built from an independent data set of nine participants. Mean and maximum absolute and relative-to-superior-sagittal-sinus SUVs were extracted from the entire 50 minutes (SUV₅₀) and last 10 minutes (SUV₁₀) of acquisition. SUV versus K_i Spearman correlation, SUV and K_i meningioma versus posttreatment-change Mann-Whitney U tests, and SUV₅₀ versus SUV₁₀ Wilcoxon matched-pairs signed rank tests were performed. Results Absolute and relative maximum SUV₅₀ demonstrated a strong positive correlation with Patlak K_i in meningioma (r = 0.82, P < .001 and r = 0.85, P < .001, respectively) and posttreatment-change lesions (r = 0.88, P = .007 and r = 0.83, P = .02, respectively). Patlak K_i images yielded higher lesion contrast by mitigating nonspecific background signal. All SUV₅₀ and SUV₁₀ metrics differed between meningioma and posttreatment-change regions (P < .001). Within the meningioma group, SUV₁₀ attained higher mean scores than SUV₅₀ (P < .001). Conclusion Combined SUV and Patlak K _i ⁶⁸Ga-DOTATATE PET/MRI enabled multiparametric evaluation of meningioma, offering the potential to enhance lesion contrast with K_i imaging and optimize the SUV measurement postinjection window. Keywords: Molecular Imaging-Clinical Translation, Neuro-Oncology, PET/MRI, Dynamic, Patlak ClinicalTrials.gov registration no. NCT04081701 © RSNA, 2022.

PET/MR Imaging of Somatostatin Receptor Expression and Tumor Vascularity in Meningioma: Implications for Pathophysiology and Tumor Outcomes

Background and Purpose

Meningiomas, the most common primary intracranial tumor, are vascular neoplasms that express somatostatin receptor-2 (SSTR2). The purpose of this investigation was to evaluate if a relationship exists between tumor vascularity and SSTR2 expression, which may play a role in meningioma prognostication and clinical management.

Materials and Methods

Gallium-68-DOTATATE PET/MRI with dynamic contrast-enhanced (DCE) perfusion was prospectively performed. Clinical and demographic patient characteristics were recorded. Tumor volumes were segmented and superimposed onto parametric DCE maps including flux rate constant (Kep), transfer constant (Ktrans), extravascular volume fraction (Ve), and plasma volume fraction (Vp). Meningioma PET standardized uptake value (SUV) and SUV ratio to superior sagittal sinus (SUVR_SSS) were recorded. Pearson correlation analyses were performed. In a random subset, analysis was repeated by a second investigator, and intraclass correlation coefficients (ICCs) were determined.

Results

Thirty-six patients with 60 meningiomas (20 WHO-1, 27 WHO-2, and 13 WHO-3) were included. Mean Kep demonstrated a strong significant positive correlation with SUV (r = 0.84, p < 0.0001) and SUVR_SSS (r = 0.81, p < 0.0001). When stratifying by WHO grade, this correlation persisted in WHO-2 (r = 0.91, p < 0.0001) and WHO-3 (r = 0.92, p = 0.0029) but not WHO-1 (r = 0.26, p = 0.4, SUVR_SSS). ICC was excellent (0.97–0.99).

Conclusion

DOTATATE PET/MRI demonstrated a strong significant correlation between tumor vascularity and SSTR2 expression in WHO-2 and WHO-3, but not WHO-1 meningiomas, suggesting biological differences in the relationship between tumor vascularity and SSTR2 expression in higher-grade meningiomas, the predictive value of which will be tested in future work.

Exploring the association between use of gonadotropin releasing hormones agonists and prostate cancer diagnosis per se and diabetes control in men with type 2 diabetes mellitus: a nationwide, population-based cohort study

BACKGROUND

Gonadotropin Releasing Hormones agonists (GnRH), which are first line treatment for metastatic prostate cancer (PCa), increase risk of type 2 diabetes mellitus (T2DM). This study aims to quantify the association of use of GnRH with diabetes control in PCa men with T2DM.

METHODS

Nationwide population-based cohort study in the Swedish National Diabetes Register and Prostate Cancer data Base Sweden 4.1, on the association between GnRH and diabetes control in T2DM men with PCa by comparing T2DM men with PCa vs. without PCa, as well as comparing T2DM men with PCa on or not on GnRH. The primary exposure was use of GnRH. Worsening diabetes control was the primary outcome, defined as: 1) HbA1c rose to 58 mmol/mol or higher; 2) HbA1c increase by 10 mmol/mol or more; 3) Start of antidiabetic drugs or switch to insulin. We also combined all above definitions. Cox proportional hazards regression was used to analyze the association.

RESULTS

There were 5714 T2DM men with PCa of whom 692 were on GnRH and 28,445 PCa-free men with T2DM with similar baseline characteristics. Diabetes control was worse in men with GnRH vs. PCa-free men (HR: 1.24, 95% CI: 1.13-1.34) as well as compared with PCa men without GnRH (HR:1.58, 95% CI: 1.39-1.80), when we defined the worsening control of diabetes by combining all definitions above.

CONCLUSION

Use of GnRH in T2DM men with PCa was associated with worse glycemic control. The findings highlight the need to closely monitor diabetes control in men with T2DM and PCa starting GnRH.

Prefertilization Exposure of Rainbow Trout Eggs to Per- and Polyfluoroalkyl Substances to Simulate Accumulation During Oogenesis

Aqueous film-forming foams (AFFFs) are used in firefighting and are sources of per- and polyfluoroalkyl substances (PFAS) to the environment through surface runoff and groundwater contamination at defense and transportation sites. Little is known regarding the toxicity and bioaccumulation of newer AFFF formulations containing novel PFAS. To mimic maternal transfer of PFAS, prefertilization rainbow trout eggs were exposed to three PFAS using novel methodologies. Batches of unfertilized oocytes were exposed for 3 h to 0, 0.01, 0.1, 1, or 10 µg/ml separately to perfluorooctanoic acid, perfluorohexanoic acid, or perfluorooctanesulfonic acid in either coelomic fluid or Cortland's solution. After exposure, the gametes were fertilized and rinsed with dechlorinated water. Egg yolk was aspirated from a subset of fertilized eggs for PFAS quantification. Each PFAS was detected in yolks of eggs exposed to the respective PFAS, and yolk concentrations were directly proportional to concentrations in aqueous media to which they were exposed. Exposure in coelomic fluid or Cortland's solution resulted in similar concentrations of PFAS in egg yolks. Ratios of PFAS concentrations in oocytes to concentrations in exposure media (oocyte fluid ratios) were <0.99 when exposed from 0.01 to 10 µg/ml and <0.45 when exposed from 0.1 to 10 µg/ml for both media and all three PFAS, demonstrating that the water solubility of the chemicals was relatively great. Prefertilization exposure of eggs effectively introduced PFAS into unfertilized egg yolk. This method provided a means of mimicking maternal transfer to evaluate toxicity to developing embryos from an early stage. This method is more rapid and efficient than injection of individual fertilized eggs and avoids trauma from inserting needles into eggs. Environ Toxicol Chem 2021;40:3159-3165. © 2021 SETAC.

NEIM-05. [GA68]DOTATATE PET/MRI-BASED RADIOSURGICAL RESPONSE ASESSMENT IN MENINGIOMA

PURPOSE

Postoperative PET/MRI with [68Ga]-DOTATATE can differentiate residual meningioma from postsurgical change, aid in target delineation, and portend a more favorable dosimetry with decreased PTV and organ-at-risk dose. Our purpose was to demonstrate utility of DOTATATE PET/MR for radiosurgical treatment (RT) response assessment in meningiomas.

METHODS

Patients underwent postoperative radiation treatment planning using DOTATATE PET/MRI as part of our IRB-approved prospective trial. Both DOTATATE PET and gadolinium-enhanced T1 weighted MR imaging were incorporated in RT-planning. All patients underwent follow-up DOTATATE PET/MRI at 6-12 months following completion of radiosurgery. Maximum absolute standardized uptake value (SUV) and SUV ratio (SUVR) of lesion/ superior sagittal sinus SUV were obtained. RANO criteria were applied to determine significance of change in size. Statistical analyses were performed using paired t-tests.

RESULTS

13 patients (15% WHO-I, 54% WHO-II, 23% WHO-III, 8% WHO grade unknown) were followed postoperatively with pre- and post-RT DOTATATE PET/MRI. 29 meningiomas were treated. 46% (6/13) of subjects received SBRT and 54% (7/13) received SRS. Post-RT DOTATATE PET/MRI demonstrated a 46.4% SUV decrease (p-value = 0.0001) and a 60.8% SUVR decrease (p-value &lt; 0.0001). Of 21 measurable lesions, the size product decreased by 21%; while this decrease was statistically significant (p-value = 0.0008), it was below the 25% decrease defined as clinically significant by RANO guidelines. To date, all patients remain stable radiographically without evidence of recurrence (mean follow-up post RT: 14 months; range: 6-24 months).

CONCLUSIONS

DOTATATE PET SUV and SUVR demonstrated marked, significant decrease post radiosurgery. Lesion size decrease was statistically significant but not clinically significant by RANO criteria. DOTATATE PET/MR thus represents a promising approach to aid in response assessment for radiosurgically treated meningiomas. Longer-term follow-up is needed to determine the correlation between the degree of post-RT SUV and/or SUVR decrease and progression-free-survival.

Heuristic scoring method utilizing FDG-PET statistical parametric mapping in the evaluation of suspected Alzheimer disease and frontotemporal lobar degeneration

Distinguishing frontotemporal lobar degeneration (FTLD) and Alzheimer Disease (AD) on FDG-PET based on qualitative review alone can pose a diagnostic challenge. SPM has been shown to improve diagnostic performance in research settings, but translation to clinical practice has been lacking. Our purpose was to create a heuristic scoring method based on statistical parametric mapping z-scores. We aimed to compare the performance of the scoring method to the initial qualitative read and a machine learning (ML)-based method as benchmarks. FDG-PET/CT or PET/MRI of 65 patients with suspected dementia were processed using SPM software, yielding z-scores from either whole brain (W) or cerebellar (C) normalization relative to a healthy cohort. A non-ML, heuristic scoring system was applied using region counts below a preset z-score cutoff. W z-scores, C z-scores, or WC z-scores (z-scores from both W and C normalization) served as features to build random forest models. The neurological diagnosis was used as the gold standard. The sensitivity of the non-ML scoring system and the random forest models to detect AD was higher than the initial qualitative read of the standard FDG-PET [0.89-1.00 vs. 0.22 (95% CI, 0-0.33)]. A categorical random forest model to distinguish AD, FTLD, and normal cases had similar accuracy than the non-ML scoring model (0.63 vs. 0.61). Our non-ML-based scoring system of SPM z-scores approximated the diagnostic performance of a ML-based method and demonstrated higher sensitivity in the detection of AD compared to qualitative reads. This approach may improve the diagnostic performance.