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Knowledge of the intrinsic variability of radiomic features is essential to the proper interpretation of changes in these features over time. The primary aim of this study was to assess the test–retest repeatability of radiomic features extracted from 18F-FDG PET images of cervical tumors. The impact of different image preprocessing methods was also explored. Methods: Patients with cervical cancer underwent baseline and repeat 18F-FDG PET/CT imaging within 7 d. PET images were reconstructed using 2 methods: ordered-subset expectation maximization (PETOSEM) or ordered-subset expectation maximization with point-spread function (PETPSF). Tumors were segmented to produce whole-tumor volumes of interest (VOIWT) and 40% isocontours (VOI40). Voxels were either left at the default size or resampled to 3-mm isotropic voxels. SUV was discretized to a fixed number of bins (32, 64, or 128). Radiomic features were extracted from both VOIs, and repeatability was then assessed using the Lin concordance correlation coefficient (CCC). Results: Eleven patients were enrolled and completed the test–retest PET/CT imaging protocol. Shape, neighborhood gray-level difference matrix, and gray-level cooccurrence matrix features were repeatable, with a mean CCC value of 0.81. Radiomic features extracted from PETOSEM images showed significantly better repeatability than features extracted from PETPSF images (P 0.96) when extracted from VOI40. Conclusion: Shape, gray-level cooccurrence matrix, and neighborhood gray-level difference matrix radiomic features were consistently repeatable, whereas gray-level run length matrix and gray-level zone length matrix features were highly variable. Radiomic features extracted from VOI40 were more repeatable than features extracted from VOIWT. Changes in voxel size or SUV discretization parameters typically resulted in relatively small differences in feature value, though several features were highly sensitive to these changes.

BACKGROUND Among patients with cervical cancer, little is known about the significance of persistent human papillomavirus (HPV) expression after chemoradiation (CRT). This study evaluated associations between early posttreatment HPV clearance and patient outcomes with an added focus on the value of posttherapy positron emission tomography (PET) imaging. METHODS Included patients underwent pretreatment testing indicating a high-risk HPV infection and posttreatment testing with a messenger RNA (mRNA)-based genital swab after CRT. Posttherapy responses were stratified on the basis of HPV mRNA detection into an early clearance (EC) group (no mRNA) and a persistent expression (PE) group (detectable mRNA) on the basis of an evaluation at a median of 6 weeks after therapy. The Kaplan-Meier method was used to compare outcomes, and multivariable analysis was used to identify predictors of outcomes. RESULTS Seventy-two of the 97 eligible patients (74.2%) had EC. The mean follow-up time was 25 months (range, 4-56 months), and 2-year pelvic control (76.9% vs 50.2%; P = .01) and overall survival (OS; 80.9% vs 52.2%; P

ObjectiveCompared with 3D-planned pelvic radiation, intensity-modulated radiation therapy (IMRT) has been shown to reduce acute toxicity in cervical cancer patients after radical hysterectomy. This study evaluated late toxicity and patterns of failure after post-operative pelvic IMRT interdigitated weekly with high dose rate brachytherapy.MethodsThis retrospective study included 53 cervical cancer patients treated between January 2006 and August 2019 with radical hysterectomy, lymphadenectomy, and post-operative IMRT and high dose rate brachytherapy. The decision to include chemotherapy was made by the treating gynecologic oncologist based on patient-specific criteria including positive pelvic lymph nodes, positive surgical margins, or positive parametrial invasion. The actuarial rates of genitourinary and gastrointestinal toxicity, vaginal cuff/regional nodal/distant failure, and overall survival were calculated using the Kaplan–Meier method.ResultsMedian follow-up was 70 months (range 5.4–148) months and age at diagnosis was 47 (range 24–73) years. The 2018 International Federation of Gynecology and Obstetrics (FIGO) clinical stages were IB1 (n=19), IB2 (n=7), IIB (n=7), IIIC1 (n=19), and IIIC2 (n=1). Median radiation dose delivered in 160 cGy daily fractions was 5120 (range 4640–5120) cGy. Median brachytherapy dose prescribed to the vaginal surface delivered in six weekly fractions was 2400 (range 1200–4800) cGy. Concurrent chemotherapy was delivered in 35 (66%) patients. There were no acute grade >3 genitourinary or gastrointestinal toxicities. Late grade >3 occurred in two (3.8%) patients, including a small bowel obstruction and a ureteral stricture. The 5-year actuarial rate for gastrointestinal or genitourinary toxicity was 1.9%. There were no vaginal cuff recurrences. The 5-year actuarial rates for regional nodal failure, distant failure outside the radiation field, any failure, and overall survival were 11%, 11%, 14%, and 85%, respectively.ConclusionsPost-operative IMRT with high dose rate brachytherapy for patients with cervical cancer is associated with excellent outcomes and limited rates of radiation-related non-hematologic toxicity.

In the Province of Flevoland, the Netherlands, land subsidence poses a problem to agriculture and water management. The peat layers in the soil are susceptible to compression and oxidation causing further subsidence. Applying subirrigation through the tile drain system to maintain saturation of the peat may be a measure to slow down subsidence. A study was therefore carried out at two sites, Nagele and Zeewolde, to assess the impact of subirrigation in the peat on the seasonal variation in soil moisture content, and corresponding redox conditions. Bacterial community analysis was carried out to verify the hydrochemical observations. Subirrigation proved to be an efficient measure to maintain a high water level in the peat soil as long as the permeability in the upper part of the peat was sufficient to allow transmission of water into the inter-drain area and when the peat layer extended enough below the minimum regional water level to prevent drainage to the sand layer underneath. The peat showed dual porosity and water levels could well be maintained by subirrigation at the Nagele site. At the Zeewolde site, the variability in the thin peat layer allowed drainage to occur in the sand layer, preventing subirrigation to maintain high water levels. However, at both sites the peat layer remained close to saturation throughout the summer, which may be caused by the fine-grained mineral layer isolating the peat from water extraction via evapotranspiration. Nitrate concentrations of up to 100 mg L−1 were observed were high (>50 mg L−1) in the oxic mineral top layer but were low in the peat (0.3 mg L−1) at both Nagele and Zeewolde sites. Sulphate concentrations also showed a decrease with depth in the peat at Nagele, indicating a transition from sub-oxic above 1.5 m depth to anoxic conditions at 3.5 m depth. The hydrochemical observations in the soil moisture in the peat at Nagele confirmed that conditions were sub-oxic in the upper part of the peat (0.7 m below soil surface) to anoxic at greater depth (3.5 m). Soil microbe analyses showed few nitrification bacteria in the peat, whereas communities specialised in denitrification and ammonification were present, as well as sulphate reducing bacteria and methanogenic species. This confirmed the sub-oxic to anoxic conditions in the peat deduced from the hydrochemical observations. At Zeewolde, conditions remained sub-oxic throughout the profile.

A series of five benzimidazole-based compounds were identified using a machine learning algorithm as potential inhibitors of the respiratory syncytial virus (RSV) fusion protein. These compounds were synthesized, and compound 2 in particular exhibited excellent in vitro potency with an EC(50) value of 5 nM. This new scaffold was then further refined leading to the identification of compound 44, which exhibited a 10-fold improvement in activity with an EC(50) value of 0.5 nM.

The purpose of this study was to determine if strategic placement of portable air purifiers would improve effectiveness of aerosol reduction in a space as compared to use as a general room air purifier. Two sizes of portable air purifiers were placed in two different positions intended to function similar to either a local exhaust ventilation hood or an air curtain to determine if strategic placement would lead to a reduction of particles in a worker’s position at a desk in an office environment. Particle generators were used to introduce particulate into the air and personal aerosol monitors measured particles during each test condition. Results showed that when the medium room portable air purifiers used in this study were set to high, corresponding to 98 CFM, and placed near the breathing zone of each office worker with the unit’s filter cover removed, the particle concentration was reduced 35% beyond the reduction that would be expected if the same units were placed on the floor behind the occupant’s workstation. Results also indicated that the larger portable air purifier tested, positioned as close as reasonable to each occupant’s breathing zone with the largest capture area possible (i.e., removing the unit’s filter cover), delivers the best aerosol reduction performance. The authors concluded that as a layer of protection against transmission of airborne infectious organisms for office occupants, installing a portable air purifier, sized and operated similar to the units tested in this study on the desk 12 inches from the breathing zone of the worker, has the potential to reduce airborne particulate to a greater degree than if the same units were placed outside of the breathing zone, in the general cubicle area.

Background: Systematic evaluation of neighborhood factors which capture an array of characteristics -analogous to genome-wide-association studies- may identify important patterns in spatial determinants of blood pressure control. Methods: Our sample included Health and Retirement Study participants (N=13180; 58% women, 13% non-Hispanic Black, 4% Hispanic/Latino) with at least one sphygmomanometer reading taken between 2006 and 2016. Our main study outcome was at least one hypertensive blood pressure measurement over the study period. Participants were randomly assigned to either a training or test dataset. Using generalized estimating equations, we summarized multivariable associations between each of 51 standardized American Community Survey sociodemographic, housing, and income-related census tract variables (2005-09) and the period prevalence of measured hypertension. We adjusted for individual factors and accounted for multiple comparisons in the training set using the Simes significance test. Neighborhood-based factors that revealed statistically significant associations (Simes-adjusted p-value Results: Thirty-two percent (4218 out of 13180) of participants had at least one hypertensive sphygmomanometer reading between 2006 and 2016. In the training set, two of the 51 census-tract level variables were independently associated with period prevalence of hypertension. In the full sample, we observed a lower likelihood of prevalent hypertension (OR: 0.95; 95% CI: 0.92, 0.99) among participants residing in a census tract with recent (since 2000) in-migration. A higher proportion of relatively recent (since 2000) renters in the census tract was associated with a lower hypertension prevalence (OR: 0.95; 95% CI: 0.91, 0.98). When stratified by racial/ethnic designation, these patterns were apparent among Non-Hispanic White and to some extent Hispanic/Latino but not Non-Hispanic Black participants. However, differences were not statistically significant by race or ethnicity. Conclusion: In conclusion, relatively more recent relocation to an area appears to be modestly associated with reduced prevalence of hypertension. These findings support possible differential cardiovascular health impacts of gentrification. Further investigation is needed to confirm these findings.

To describe and compare the clinical outcomes of bamlanivimab-etesevimab, casirivimab-imdevimab, and sotrovimab treatment of mild to moderate coronavirus disease 2019 (COVID-19) during the severe acute respiratory coronavirus 2 (SARS-CoV-2) B.1.617.2 Delta surge.This is a retrospective study of high-risk patients who received bamlanivimab-etesevimab, casirivimab-imdevimab, and sotrovimab for mild to moderate COVID-19 between August 1, 2021, and December 1, 2021. Rates of severe disease, hospitalization, intensive care unit admission, and death were assessed.Among 10,775 high-risk patients who received bamlanivimab-etesevimab, casirivimab-imdevimab, or sotrovimab for mild to moderate COVID-19 during the Delta surge, 287 patients (2.7%) developed severe disease that led to hospitalization, oxygen supplementation, or death within 30 days after treatment. The rates of severe disease were low among patients treated with bamlanivimab-etesevimab (1.2%), casirivimab-imdevimab (2.9%), and sotrovimab (1.6%; P.01). The higher rate of severe outcomes among patients treated with casirivimab-imdevimab may be related to a significantly lower COVID-19 vaccination rate in that cohort. Intensive care unit admission was comparable among patients treated bamlanivimab-etesevimab, casirivimab-imdevimab, or sotrovimab (1.0%, 1.0%, and 0.4%, respectively).This real-world study of a large cohort of high-risk patients shows low rates of severe disease, hospitalization, intensive care unit admission, and mortality after treatment with bamlanivimab-etesevimab, casirivimab-imdevimab, and sotrovimab for mild to moderate COVID-19 during the SARS-CoV-2 Delta surge.

To describe the management and outcomes of cervical cancer patients initially treated with radiation who had partial metabolic response (PMR) on three-month post-radiationCervical cancer patients treated with radiation between 1997 and 2013 who had PMR on initial post-therapy FDG-PET were identified from a prospectively maintained database. Descriptive statistics were used to summarize patient demographics, tumor characteristics, surveillance methods, and treatment modalities. Kaplan-Meier methods were used to estimate progression-free (PFS) and overall survival (OS) for patients who underwent cervical biopsy prior to additional therapies and for patients who were managed with chemotherapy, radiation, surgery or no intervention.PMR was identified in 81/542 (15%) women on initial post-radiation PET. Thirty women underwent cervical biopsy, of whom 14 (47%) had persistent cancer. Nine underwent treatment, (three surgery, five chemotherapy alone and one chemotherapy and radiation) but all died of disease; PFS and OS were similar whether women had surgery, chemoradiation therapy, or no treatment. A second surveillance FDG-PET had PPV and NPV of 91% and 75% for progression, respectively, and identified the 19% percent of patients with persistent disease outside of the cervix. Cervical biopsy had a higher PPV (100%) and lower NPV (62.5%) for progression. At the end of the study period, 46 (57%) patients were dead of disease, including all 8 patients (100%) with para-aortic or supraclavicular involvement.If PMR is identified on three-month FDG-PET following completion of radiation for cervical cancer, repeat FDG-PET and/or biopsy are indicated to detect persistence and assist in counseling. PMR predicts poor outcomes, particularly for those with positive cervical biopsies and lymphatic involvement.

The endogenous lysosomal cysteine protease inhibitor SERPINB3 (squamous cell carcinoma antigen 1, SCCA1) is elevated in patients with cervical cancer and other malignancies. High serum SERPINB3 is prognostic for recurrence and death following chemoradiation therapy. Cervical cancer cells genetically lacking SERPINB3 are more sensitive to ionizing radiation (IR), suggesting this protease inhibitor plays a role in therapeutic response. Here we demonstrate that SERPINB3-deficient cells have enhanced sensitivity to IR-induced cell death. Knock out of SERPINB3 sensitizes cells to a greater extent than cisplatin, the current standard of care. IR in SERPINB3 deficient cervical carcinoma cells induces predominantly necrotic cell death, with biochemical and cellular features of lysoptosis. Rescue with wild-type SERPINB3 or a reactive site loop mutant indicates that protease inhibitory activity is required to protect cervical tumor cells from radiation-induced death. Transcriptomics analysis of primary cervix tumor samples and genetic knock out demonstrates a role for the lysosomal protease cathepsin L in radiation-induced cell death in SERPINB3 knock-out cells. These data support targeting of SERPINB3 and lysoptosis to treat radioresistant cervical cancers., Wang et al. demonstrate the cytoprotective role of SERPINB3 against radiation-induced necrosis, showing that cells lacking SERPINB3 protein both in culture and in mice are more sensitive to radiation and cisplatin-induced cell death. The authors also report that the cell death induced by radiation in SERPINB3-lacking cells is lysoptosis and implicate the lysosomal protease cathepsin L in this process.

We investigate the emergence of orientational order among +1/2 disclinations in active nematic liquid crystals. Using a combination of theoretical and experimental methods, we show that +1/2 disclinations have short-range antiferromagnetic alignment, as a consequence of the elastic torques originating from their polar structure. The presence of intermediate -1/2 disclinations, however, turns this interaction from anti-aligning to aligning at scales that are smaller than the typical distance between like-sign defects. No long-range orientational order is observed. Strikingly, these effects are insensitive to material properties and qualitatively similar to what is found for defects in passive nematic liquid crystals., 6 pages, 4 figures

Bamlanivimab-etesevimab and casirivimab-imdevimab are authorized by the US Food and Drug Administration for emergency treatment of mild to moderate coronavirus disease 2019 (COVID-19) in high-risk persons. There has been no study comparing their clinical efficacy. In this retrospective study of 681 patients with mild to moderate COVID-19 during a period dominated by severe acute respiratory syndrome coronavirus 2 wild-type and alpha variants, 25 patients (3.7%) had progression to a severe outcome requiring hospitalization and oxygen supplementation within 30 days after monoclonal antibody infusion. Severe outcome was significantly higher among the 181 patients who were treated with casirivimab-imdevimab when compared with the 500 patients who received bamlanivimab-etesevimab (21 [6.6%] vs 13 [2.6%]; P=.01). Patients treated with casirivimab-imdevimab had higher odds of severe outcomes compared with those who received bamlanivimab-etesevimab (odds ratio, 2.67; 95% CI, 1.17 to 6.06). The demographic and clinical characteristics, and the time to monoclonal antibody infusion, of the 2 treatment cohorts were not significantly different. The reason behind this significant difference in the clinical outcomes is unclear, but our observations emphasize potential efficacy differences among antispike monoclonal antibodies against COVID-19. Further clinical studies using larger cohorts of patients are needed to confirm or refute these observations.

More than one-third of patients with locally advanced cervical cancer do not respond to chemoradiation therapy (CRT). We aimed to characterize the transcriptional landscape of paired human cervical tumors before and during CRT in order to gain insight into the evolution of treatment response and to elucidate mechanisms of treatment resistance. We prospectively collected cervical tumor biopsies from 115 patients both before and 3 weeks into CRT. RNA-sequencing, Gene Set Enrichment Analysis and HPV gene expression were performed on 20 paired samples that had adequate neoplastic tissue mid-treatment. Tumors from patients with no evidence of disease (NED) at last follow-up had enrichment in pathways related to the immune response both pretreatment and mid-treatment, while tumors from patients dead of disease (DOD) demonstrated enrichment in biosynthetic and mitotic pathways but not in immune-related pathways. Patients DOD had decreased expression of T-cell and cytolytic genes and increased expression of PD-L2 mid-treatment compared to patients NED. Histological and immunohistochemical analysis revealed a decrease in tumor-associated lymphocytes (TAL) during CRT in all patients but tumors from patients DOD had a significantly more pronounced decrease in TALs and CD8+ cells mid-treatment, which was validated in a larger mid-treatment cohort. Finally, patients DOD retained more HPV E6/E7 gene expression during CRT and this was associated with increased expression of genes driving mitosis, which was corroborated in vitro. Our results suggest that decreased local immune response and retained HPV gene expression may be acting together to promote treatment resistance during CRT in patients with cervical cancer.

Objective18F-fluorodeoxyglucose–positron emission tomography (FDG-PET) detection of metastatic nodal disease is useful for guiding cervical cancer treatment but the impact of tumor histology is unknown. This study reports the detection of FDG avid pelvic and para-aortic lymph nodes in patients with early stage cervical cancer with squamous carcinoma and adenocarcinoma tumor histology.MethodsPatients with International Federation of Gynecology and Obstetrics (FIGO) 2009 stage IB1-2 cervical cancer who underwent pre-surgical FDG-PET between March 1999 and February 2018 were identified in a tertiary academic center database. All patients had radical hysterectomy with pelvic and para-aortic lymph node dissection. Detection of pelvic and para-aortic lymph nodes by FDG-PET versus surgical dissection was compared. FDG-PET sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were determined and stratified by tumor histology.ResultsWe identified 212 patients with early stage cervical cancer (84% FIGO IB1, 16% IB2) who underwent pre-surgical FDG-PET; 137 (65%) patients had squamous carcinoma and 75 (35%) patients had adenocarcinoma. PET/computed tomography was performed in 189 (89%) patients and 23 (11%) had PET only. Surgical dissection revealed positive pelvic and para-aortic lymph nodes in 25% and 3.3% of patients, respectively. For squamous carcinoma, sensitivity, specificity, PPV, and NPV of FDG-PET for pelvic nodal metastasis were 44%, 99%, 95%, and 78%, respectively. For adenocarcinoma, the corresponding results for pelvic nodal metastasis were 25%, 99%, 67%, and 92%, respectively. The overall values for sensitivity, specificity, PPV, and NPV of FDG-PET for para-aortic nodal metastasis were 29%, 99%, 67%, and 98%, respectively.DiscussionPelvic nodal metastasis was less likely to be detected by FDG-PET in patients with early stage adenocarcinoma than with squamous carcinoma.

Intensity modulated radiation therapy and 3-dimensional image-guided adapted brachytherapy are increasingly used for definitive cervical cancer treatment. We compared patterns of failure and survival in patients treated with these modalities with results from patients treated with 2-dimensional external beam radiation therapy and brachytherapy. All patients received a pretreatment positron emission tomography scan, and all surviving patients had a minimum of 5 years of follow-up. Intensity modulated radiation therapy and 3-dimensional image-guided adapted brachytherapy were associated with higher survival and reduced late bowel and bladder toxicities compared with 2-dimensional external beam radiation therapy and brachytherapy. PURPOSE: This study reported long-term outcomes of patients with cervical cancer who were treated with intensity modulated radiation therapy and 3-dimensional (3D) image-guided adapted brachytherapy (IMRT/3D-IGABT) compared with those treated with 2-dimensional (2D) external irradiation and 2D brachytherapy (2D EBRT/BT). METHODS AND MATERIALS: This study included patients with newly diagnosed cervical cancer and pretreatment fluorodeoxyglucose positron emission tomography scans who were treated with curative-intent irradiation from 1997 to 2013. The treatment policy changed from using 2D EBRT/BT to IMRT/3D-IGABT in 2005. Patterns of recurrence, cancer-specific survival (CSS), and overall survival (OS) were evaluated. Late gastrointestinal and genitourinary toxicity were scored with National Cancer Institute Common Terminology Criteria for Adverse Events. RESULTS: The median follow-up for patients alive at the time of last follow-up in the 2D EBRT/BT group (n = 300) was 15.3 years (range, 10.8–20.5 years). In the IMRT/3D-IGABT group (n = 300), it was 7 years (range, 5–12.4 years). According to the International Federation of Gynecology and Obstetrics, 33% of tumors were stage IB1 to IB2, 41% were stage IIA to IIB, and 26% were stage IIIA to IVA. The results after 5 years for patients treated with 2D EBRT/BT showed that freedom from relapse (FFR) was 57%, CSS was 62%, and OS was 57%. For the IMRT/3D-IGABT group, the 5-year results showed that FFR was 65% (P = .04), CSS was 69% (P = .01), and OS was 61% (P = .04). When stratified by lymph node status according to positron emission tomography scan results, disease control was most improved with IMRT/3D-IGABT versus 2D EBRT/BT in patients with positive pelvic lymph nodes only (P = .02). Cumulatively, 88 of 600 patients (15%) had grade ≥3 late bowel/bladder toxicity. The 2D EBRT/BT group had 55 patients (18%), and the IMRT/3D-IGABT group had 33 patients (11%; P = .02). CONCLUSIONS: IMRT/3D-IGABT was associated with improved survival and decreased gastrointestinal and genitourinary toxicity in patients with cervical cancer compared with those who received 2D EBRT/BT.

ObjectiveThe detection of distant metastatic disease in cervical cancer patients at diagnosis is critical in accurate prognostication and directing treatment strategies. This study describes the frequency and sites of distant metastatic disease at diagnosis in patients with cervical cancer as detected by positron emission tomography with 18F-fluorodeoxyglucose (FDG-PET).MethodsPatients with newly diagnosed cervical cancer underwent pre-treatment whole-body FDG-PET starting in 1997 at an academic institution. Patients with evidence of distant FDG-avid disease, defined as disease outside of typical sites of lymphatic spread, were included for analyses. Patients were not surgically staged, but biopsy to confirm metastatic disease was attempted at the discretion of the treating physicians. Overall survival was calculated using Kaplan-Meier analysis.ResultsFrom 1997 to 2017, 72 (6.2%) of 1158 consecutively evaluated cervical cancer patients exhibited FDG-avid distant disease at diagnosis; 27 (38%) of these had biopsy confirmation of distant disease. Only 35 (49%) of FDG-detected metastases were clinically apparent. The sites of distant disease were lung (35%), multiple sites (25%), omentum (16.5%), bone (16.5%), and liver (7%). There were 12 (17%) patients with distant disease who did not display FDG-avid lymph nodes. Median overall survival among patients with distant FDG-avid disease was 7.0 months (95% CI 4.3 to 9.7). Patients with multiple sites of distant disease demonstrated the worst overall survival.ConclusionsDistant metastatic disease detected by FDG-PET is found in 6.2% of patients with cervical cancer at the time of initial diagnosis and the most common site of disease is the lung. Further prospective investigation is warranted to delineate best treatment practices for cervical cancer patients presenting with distant metastases.

Knowledge of the within-subject variability of 18F-FDG PET/MRI measurements is necessary for proper interpretation of quantitative PET or MRI metrics in the context of therapeutic efficacy assessments with integrated PET/MRI scanners. The goal of this study was to determine the test-retest repeatability of these metrics on PET/MRI, with comparison to similar metrics acquired by PET/CT. Methods: This prospective study enrolled subjects with pathology-proven pelvic malignancies. Baseline imaging consisted of PET/CT immediately followed by PET/MRI, using a single 370-MBq 18F-FDG dose. Repeat imaging was performed within 7 d using an identical imaging protocol, with no oncologic therapy between sessions. PET imaging on both scanners consisted of a list-mode acquisition at a single pelvic station. The MRI consisted of 2-point Dixon imaging for attenuation correction, standard sequences for anatomic correlation, and diffusion-weighted imaging. PET data were statically reconstructed using various frame durations and minimizing uptake time differences between sessions. SUV metrics were extracted for both PET/CT and PET/MRI in each imaging session. Apparent diffusion coefficient (ADC) metrics were extracted for both PET/MRI sessions. Results: The study cohort consisted of 14 subjects (13 female, 1 male) with various pelvic cancers (11 cervical, 2 rectal, 1 endometrial). For SUVmax, the within-subject coefficient of variation (wCV) appeared higher for PET/CT (8.5%-12.8%) than PET/MRI (6.6%-8.7%) across all PET reconstructions, though with no significant repeatability differences (all P values ≥ 0.08) between modalities. For lean body mass-adjusted SUVpeak, the wCVs appeared similar for PET/CT (9.9%-11.5%) and PET/MRI (9.2%-11.3%) across all PET reconstructions, again with no significant repeatability differences (all P values ≥ 0.14) between modalities. For PET/MRI, the wCV for ADCmedian of 3.5% appeared lower than the wCVs for SUVmax (6.6%-8.7%) and SULpeak (9.2%-11.3%), though without significant repeatability differences (all P values ≥ 0.23). Conclusion: For solid tumors of the pelvis, the repeatability of the evaluated SUV and ADC metrics on 18F-FDG PET/MRI is both acceptably high and similar to previously published values for 18F-FDG PET/CT and MRI, supporting the use of 18F-FDG PET/MRI for quantitative oncologic treatment response assessments.