Quantitative SPECT/CT Metrics in Early Prediction of [177Lu]Lu-DOTATATE Treatment Response in Gastroenteropancreatic Neuroendocrine Tumor Patients.

Our objective is to explore quantitative imaging markers for early prediction of treatment response in patients with gastroenteropancreatic neuroendocrine tumors (GEP-NETs) undergoing [177Lu]Lu-DOTATATE therapy. By doing so, we aim to enable timely switching to more effective therapies in order to prevent time-resource waste and minimize toxicities. Methods: Patients diagnosed with unresectable or metastatic, progressive, well-differentiated, receptor-positive GEP-NETs who received 4 sessions of [177Lu]Lu-DOTATATE were retrospectively selected. Using SPECT/CT images taken at the end of treatment sessions, we counted all visible tumors and measured their largest diameters to calculate the tumor burden score (TBS). Up to 4 target lesions were selected and semiautomatically segmented. Target lesion peak counts and spleen peak counts were measured, and normalized peak counts were calculated. Changes in TBS (ΔTBS) and changes in normalized peak count (ΔnPC) throughout treatment sessions in relation to the first treatment session were calculated. Treatment responses were evaluated using third-month CT and were binarized as progressive disease (PD) or non-PD. Results: Twenty-seven patients were included (7 PD, 20 non-PD). Significant differences were observed in ΔTBSsecond-first, ΔTBSthird-first, and ΔTBSfourth-first (where second-first, third-first, and fourth-first denote scan number between the second and first, third and first, and fourth and first [177Lu]Lu-DOTATATE treatment cycles), respectively) between the PD and non-PD groups (median, 0.043 vs. -0.049, 0.08 vs. -0.116, and 0.109 vs. -0.123 [P = 0.023, P = 0.002, and P < 0.001], respectively). ΔnPCsecond-first showed significant group differences (mean, -0.107 vs. -0.282; P = 0.033); ΔnPCthird-first and ΔnPCfourth-first did not reach statistical significance (mean, -0.122 vs. -0.312 and -0.183 vs. -0.405 [P = 0.117 and 0.067], respectively). At the optimal threshold, ΔTBSfourth-first exhibited an area under the curve (AUC) of 0.957, achieving 100% sensitivity and 80% specificity. ΔTBSsecond-first and ΔTBSthird-first reached AUCs of 0.793 and 0.893, sensitivities of 71.4%, and specificities of 85% and 95%, respectively. ΔnPCsecond-first, ΔnPCthird-first, and ΔnPCfourth-first showed AUCs of 0.764, 0.693, and 0.679; sensitivities of 71.4%, 71.4%, and 100%; and specificities of 75%, 70%, and 35%, respectively. Conclusion: ΔTBS and ΔnPC can predict [177Lu]Lu-DOTATATE response by the second treatment session.

Radiologic Findings of Cricoid Chondronecrosis after Intubation in the Setting of COVID-19.

This case series examines seven patients diagnosed with cricoid chondronecrosis after intubation in the setting of COVID-19 and presents a novel "cricoid chondronecrosis computed tomography (CT) grading rubric" to standardize reporting of radiological findings. Application of this radiological grading rubric can improve communication among clinicians and radiologists and aid in prognosis determination of patients with cricoid chondronecrosis. Laryngoscope, 2024.

Characteristics of Recurrent Visions of the Nonphysical World Among Cognitively Unimpaired Elders of the Ojibwe Tribal Nation.

Importance: Visual hallucinations are a core feature of dementia with Lewy bodies and primary psychiatric disease, yet identification of a hallucination vs normal spiritual experience depends on cultural context. Almost no information exists in the medical literature regarding normal spiritual experiences in American Indian participants in the context of a neurocognitive evaluation. Objective: To assess the characteristics of a normal spiritual experience in an Ojibwe Tribal Nation. Design, Setting, and Participants: This prospective, cross-sectional study was conducted between August 1, 2021, and August 31, 2022, among an Ojibwe Tribal Nation in northern Minnesota. Participants were evaluated at their tribal nation clinic. Cognitively unimpaired tribal Elders who were enrolled members of the tribal nation and aged 55 years or older were invited to participate via fliers, radio advertisements, and health fair presentations. Thirty-seven tribal Elders volunteered. Main Outcomes and Measures: Each participant was asked whether they experienced hallucinations or visions of people, animals, or objects that are not part of the physical world. This was an a priori formulated question and part of a comprehensive neurocognitive evaluation consisting of history and physical examination (including cognitive screening with a subspecialty-trained behavioral neurologist); blood tests for metabolic, nutritional, and thyroid conditions; and noncontrast magnetic resonance imaging brain scan. Four patients were excluded from the present analysis due to having mild cognitive impairment or dementia. Results: Thirty-three cognitively unimpaired tribal Elders (mean [SD] age, 66.0 [7.5] years; 22 women [67%]) were included. Sixteen (48%) answered affirmatively, reporting recurrent visions of the nonphysical world. Generally, these visions were well formed, benevolent in nature, and transient; started in preadolescence; involved spirits or ancestors; and were congruent with cultural and spiritual beliefs of the Ojibwe people. No patients had accompanying dream enactment behavior, dysautonomia, parkinsonism, sleep transition-related hallucinations, or moderate to severe depression to suggest a prodrome of an α-synucleinopathy, hypnopompic or hypnagogic hallucinations, or psychosis. Conclusions and Relevance: Although based on only 1 Ojibwe Tribal Nation, this study suggests that formed visions of the nonphysical world are common among cognitively healthy Ojibwe individuals and can represent normal spiritual experiences. Clinicians would benefit from careful consideration of cultural or spiritual context to avoid misdiagnosis of neuropsychiatric disease.

Nicotinamide enhances natural killer cell function and yields remissions in patients with non-Hodgkin lymphoma.

Allogeneic natural killer (NK) cell adoptive transfer has shown the potential to induce remissions in relapsed or refractory leukemias and lymphomas, but strategies to enhance NK cell survival and function are needed to improve clinical efficacy. Here, we demonstrated that NK cells cultured ex vivo with interleukin-15 (IL-15) and nicotinamide (NAM) exhibited stable induction of l-selectin (CD62L), a lymphocyte adhesion molecule important for lymph node homing. High frequencies of CD62L were associated with elevated transcription factor forkhead box O1 (FOXO1), and NAM promoted the stability of FOXO1 by preventing proteasomal degradation. NK cells cultured with NAM exhibited metabolic changes associated with elevated glucose flux and protection against oxidative stress. NK cells incubated with NAM also displayed enhanced cytotoxicity and inflammatory cytokine production and preferentially persisted in xenogeneic adoptive transfer experiments. We also conducted a first-in-human phase 1 clinical trial testing adoptive transfer of NK cells expanded ex vivo with IL-15 and NAM (GDA-201) combined with monoclonal antibodies in patients with relapsed or refractory non-Hodgkin lymphoma (NHL) and multiple myeloma (MM) (NCT03019666). Cellular therapy with GDA-201 and rituximab was well tolerated and yielded an overall response rate of 74% in 19 patients with advanced NHL. Thirteen patients had a complete response, and 1 patient had a partial response. GDA-201 cells were detected for up to 14 days in blood, bone marrow, and tumor tissues and maintained a favorable metabolic profile. The safety and efficacy of GDA-201 in this study support further development as a cancer therapy.

Use of a Commercial 7-T MRI Scanner for Clinical Brain Imaging: Indications, Protocols, Challenges, and Solutions-A Single-Center Experience.

The first commercially available 7-T MRI scanner (Magnetom Terra) was approved by the FDA in 2017 for clinical imaging of the brain and knee. After initial protocol development and sequence optimization efforts in volunteers, the 7-T system, in combination with an FDA-approved 1-channel transmit/32-channel receive array head coil, can now be routinely used for clinical brain MRI examinations. The ultrahigh field strength of 7-T MRI has the advantages of improved spatial resolution, increased SNR, and increased CNR but also introduces an array of new technical challenges. The purpose of this article is to describe an institutional experience with the use of the commercially available 7-T MRI scanner for routine clinical brain imaging. Specific clinical indications for which 7-T MRI may be useful for brain imaging include brain tumor evaluation with possible perfusion imaging and/or spectroscopy, radiotherapy planning; evaluation of multiple sclerosis and other demyelinating diseases, evaluation of Parkinson disease and guidance of deep brain stimulator placement, high-detail intracranial MRA and vessel wall imaging, evaluation of pituitary pathology, and evaluation of epilepsy. Detailed protocols, including sequence parameters, for these various indications are presented, and implementation challenges (including artifacts, safety, and side effects) and potential solutions are explored.

Differentiation between primary CNS lymphoma and atypical glioblastoma according to major genomic alterations using diffusion and susceptibility-weighted MR imaging.

PURPOSE: We aimed to differentiate primary central nervous system lymphoma (PCNSL) from atypical glioblastoma (GB) and distinguish major genomic subtypes between these tumors using susceptibility-weighted imaging (SWI) along with diffusion-weighted imaging (DWI). METHODS: Thirty-one immuno-competent patients with PCNSL stratified by BCL2 and MYC rearrangement, and 57 patients with atypical GB (no visible necrosis) grouped according to isocitrate dehydrogenase-1 (IDH1) mutation status underwent 3.0-Tesla MRI before treatment in this retrospective study. Region of interest analysis with apparent diffusion coefficient (ADC) and SWI signal intensity values of the tumors were normalized by dividing those of contralateral white matter. The independent-samples t-test and Kruskal-Wallis test were utilized to compare parameters. The diagnostic ability of each parameter and their optimal combination was evaluated by logistic regression analysis and receiver operating characteristic. RESULTS: PCNSL with rearrangement of both MYC and BCL2 (n = 7) [mean relative (r) ADCmean:0.87 ±â€¯0.06, rADCmin:0.72 ±â€¯0.08] demonstrated significantly lower rADCmean, and rADCmin compared to other PCNSLs (n = 24) (rADCmean:1.19 ±â€¯0.18, rADCmin:1.03 ±â€¯0.17;p < 0.001) and GBs (p < 0.001). GB without IDH1 mutation (n = 44) (mean rSWI value:0.95 ±â€¯0.15) demonstrated significantly lower rSWI value compared to GB with IDH1 mutation (n = 13) (rSWI value:1.13 ±â€¯0.09;p < 0.001) and PCNSL (p < 0.001). The incorporation of rADCmean and rSWI parameters distinguished GB with IDH1 mutation [Area under the curve (AUC):0.985] with sensitivity and specificity of 94.3 and 100 % respectively; and PCNSL with rearrangement of both MYC and BCL2 (AUC:0.982) with sensitivity and specificity of 100 % and 95.4 %, respectively. CONCLUSiONS: Combined analysis of SWI and DWI could differentiate atypical GB from PCNSL and distinguish major genomic subtypes between these tumors.

Machine Learning-Based Multiparametric Magnetic Resonance Imaging Radiomics for Prediction of H3K27M Mutation in Midline Gliomas.

OBJECTIVE: H3K27M mutation in gliomas has prognostic implications. Previous magnetic resonance imaging (MRI) studies have reported variable rates of tumoral enhancement, necrotic changes, and peritumoral edema in H3K27M-mutant gliomas, with no distinguishing imaging features compared with wild-type gliomas. We aimed to construct an MRI machine learning (ML)-based radiomic model to predict H3K27M mutation in midline gliomas. METHODS: A total of 109 patients from 3 academic centers were included in this study. Fifty patients had H3K27M mutation and 59 were wild-type. Conventional MRI sequences (T1-weighted, T2-weighted, T2-fluid-attenuated inversion recovery, postcontrast T1-weighted, and apparent diffusion coefficient maps) were used for feature extraction. A total of 651 radiomic features per each sequence were extracted. Patients were randomly selected with a 7:3 ratio to create training (n = 76) and test (n = 33) data sets. An extreme gradient boosting algorithm (XGBoost) was used in ML-based model development. Performance of the model was assessed by area under the receiver operating characteristic curve. RESULTS: Pediatric patients accounted for a larger proportion of the study cohort (60 pediatric [55%] vs. 49 adult [45%] patients). XGBoost with additional feature selection had an area under the receiver operating characteristic curve of 0.791 and 0.737 in the training and test data sets, respectively. The model achieved accuracy, precision (positive predictive value), recall (sensitivity), and F1 (harmonic mean of precision and recall) measures of 72.7%, 76.5%, 72.2%, and 74.3%, respectively, in the test set. CONCLUSIONS: Our multi-institutional study suggests that ML-based radiomic analysis of multiparametric MRI can be a promising noninvasive technique to predict H3K27M mutation status in midline gliomas.

Correlation between dynamic susceptibility contrast perfusion MRI and genomic alterations in glioblastoma.

PURPOSE: To determine if dynamic susceptibility contrast perfusion MR imaging (DSC-pMRI) can predict significant genomic alterations in glioblastoma (GB). METHODS: A total of 47 patients with treatment-naive GB (M/F: 23/24, mean age: 54 years, age range: 20-90 years) having DSC-pMRI with leakage correction and genomic analysis were reviewed. Mean relative cerebral blood volume (rCBV), maximum rCBV, relative percent signal recovery (rPSR), and relative peak height (rPH) were derived from T2* signal intensity-time curves by ROI analysis. Major genomic alterations of IDH1-132H, MGMT, p53, EGFR, ATRX, and PTEN status were correlated with DSC-pMRI-derived GB parameters. Statistical analysis was performed utilizing the independent-samples t-test, ROC (receiver operating characteristic) curve analysis, and multivariable stepwise regression model. RESULTS: rCBVmean and rCBVmax were significantly different in relation to the IDH1, MGMT, p53, and PTEN mutation status (all p < 0.05). The rPH of the p53 mutation-positive GBs (mean 5.8 ± 2.8) was significantly higher than those of the p53 mutation-negative GBs (mean 4.0 ± 1.5) (p = 0.022). Multivariable stepwise regression analysis revealed that the presence of IDH-1 mutation (B = - 2.81, p = 0.005) was associated with decreased rCBVmean; PTEN mutation (B = - 1.21, p = 0.003) and MGMT methylation (B = - 1.47, p = 0.038) were associated with decreased rCBVmax; and ATRX loss (B = - 1.05, p = 0.008) was associated with decreased rPH. CONCLUSION: Significant associations were identified between DSC-pMRI-derived parameters and major genomic alterations, including IDH-1 mutation, MGMT methylation, ATRX loss, and PTEN mutation status in GB.

Primary Cardiac Lymphoma: Three Case Reports and a Review of the Literature.

Primary cardiac lymphoma (PCL) is a rare entity that comprises only 1-2% of all cardiac tumors. Due to their scarcity and variable clinical presentation, early diagnosis is challenging. In this series, three cases of PCL from a single institution are described, which highlight the spectrum of presenting features and emphasize common principles. In the first case, a 73-year-old male who presented with dyspnea was found to have a 12.1 cm mass in the right ventricle. Biopsy via cardiac catheterization revealed diffuse large B cell lymphoma (DLBCL). He was treated with chemoimmunotherapy and survived for two months. The second case describes a 55-year-old female who presented with chest pain. Imaging revealed a 3.1 cm right atrial mass and bilateral pleural effusions, with cytology from the latter demonstrating DLBCL. She was lost to follow up after three cycles of chemoimmunotherapy. In the last case, an 80-year-old female presented with weakness. A 4.0 cm mass was discovered in the right atrium and the patient expired shortly after admission. Autopsy confirmed the diagnosis of DLBCL. These case summaries are followed by a review of the clinical presentation, diagnostic approach, and treatment outcomes of PCL.

Non-hematologic diagnosis of systemic mastocytosis: Collaboration of radiology and pathology.

Systemic mastocytosis (SM) is a hematologic disease with a wide range of clinical courses ranging from an indolent condition with normal life expectancy to exceedingly aggressive disorder with a poor prognosis. The symptoms and signs of SM result from the release of mast cell mediators with heterogeneous functions, and/or organ damage from neoplastic mast cell infiltration, or both. Diagnostic criteria for SM are well-defined by the World Health Organization (WHO). However, the diagnosis of SM can be difficult when especially it is not in the differential diagnosis. Routinely used radiologic techniques (e.g., X-ray, ultrasound, CT scans can show findings such as lytic-, sclerotic- or mixed-bone lesions, splenomegaly, hepatomegaly, retroperitoneal or periportal mesenteric lymphadenopathy, and omental thickening). It is essential to emphasize that the constellation of these radiologic findings should strongly concern of SM, especially in patients who also have a skin rash, allergic reactions, gastrointestinal tract symptoms (lasting, intermittent nausea, diarrhea), paroxysmal tachycardias, unexplained weight loss, persistent bone pain, cytopenias, liver dysfunction, eosinophilia. These findings, even coincidentally noted, will likely lead to a tissue biopsy, which reveals diagnosis (as we discussed and illustrated some tissue biopsies here). Moreover, the role of MRI and new techniques such as [18-fluorodeoxyglucose positron emission computed tomography, fibroscan] in the diagnosis of SM have been discussed. Furthermore, we reviewed the use of radiologic methods to evaluate treatment response and prognostication of SM..

Not a pearl necklace: synchronous papillary carcinoma of thyroglossal duct cyst and thyroid gland.

We report an unusual case of synchronous papillary carcinoma of thyroglossal duct cyst (TGDC) and thyroid gland. Here, the radiology findings, surgical approach and subsequent management, and pathology of an synchronous papillary carcinoma of TGDC and thyroid gland are described.

The Role of Dual-Phase FDG PET/CT in the Diagnosis and Follow-Up of Brain Tumors.

OBJECTIVE. FDG PET/CT of brain tumors is limited by background activity. Dual-phase FDG PET/CT can eliminate this limitation and allow discernment of viable tumors. Our aim was to assess the diagnostic capability of dual-phase FDG PET/CT qualitatively and quantitatively and to determine cutoff values for dual-phase FDG PET/CT in brain tumor imaging. MATERIALS AND METHODS. Retrospectively, 51 malignant brain tumors were evaluated with dual-phase FDG PET/CT in 32 patients. Acquisitions were performed 30 minutes (time 1) and 3 hours (time 2) after administration of 10 mCi (370 MBq) FDG and 6 hours of fasting. Two observers independently and qualitatively evaluated lesions. A weighted Cohen kappa was used to calculate interrater reliability and accuracy. Quantitatively, maximum standardized uptake value (SUVmax) was measured in the lesions, contralateral white matter (CWM), contralateral caudate nucleus head, and ipsilateral cerebellar cortex (CC). Lesion-to-CWM SUVmax, lesion-to-contralateral caudate nucleus head SUVmax, and lesion-to-ipsilateral CC SUVmax ratios at time 1 and time 2 were calculated. ROC analysis was used to determine optimum cutoff values, and AUC ratios were compared among quantitative parameters. Lesion outcome was determined by pathologic results (available in 15 lesions), lesion stability on serial MRI examinations (representing nonviable tumor), or decreased tumor size on serial MRI examinations after new treatment (representing viable tumor). RESULTS. Thirty-seven viable and 14 nonviable lesions were evaluated. Qualitatively, the diagnostic accuracy (first observer: κ = 0.45 to κ = 0.59; second observer: κ = 0.41 to κ = 0.66) and interrater reliability (at time 1: κ = 0.51; at time 2: κ = 0.83) improved with delayed imaging. AUC and ROC analysis showed comparably high sensitivity, specificity, and accuracy profiles for early and delayed dual-phase FDG PET/CT. Some of the proposed cutoff values were as follows: lesion SUVmax at time 1, 7.20 (sensitivity, 89.2%; specificity, 85.7%); lesion SUVmax at time 2, 7.80 (sensitivity, 97.3%; specificity, 71.4%); lesion-to-CWM SUVmax at time 1, 2.05 (sensitivity, 78.4%; specificity, 92.9%); and lesion-to-CWM SUVmax at time 2, 2.36 (sensitivity, 81.1%; specificity, 85.7%). CONCLUSION. Dual-phase FDG PET/CT improves lesion detection and diagnostic accuracy in malignant brain tumors.

Surveillance Imaging after Autologous Hematopoietic Cell Transplantation Predicts Survival in Patients with Diffuse Large B Cell Lymphoma.

The utility of surveillance imaging after autologous hematopoietic cell transplantation (AHCT) in relapsed/refractory diffuse large B cell lymphoma (DLBCL) remains unclear. The purpose of this study was to determine whether surveillance imaging predicts survival after AHCT. At the University of Minnesota, serial imaging for early relapse detection has been used prospectively for all consecutive AHCT recipients treated since 2010. The present analysis included 91 AHCT recipients with DLBCL who underwent 18F-fluorodeoxyglucose positron emission tomography (18F-FDG-PET) scan at day +100 post-AHCT. 18F-FDG-PET parameters included the Deauville (D) 5-point scale, peak standardized uptake values (SUVmax), total legion glycolysis (TLG), and total metabolic tumor volume (TMTV). Survival of patients with clinically symptomatic versus asymptomatic radiographically detected relapsed DLBCL after AHCT was compared. Sixty patients experienced relapse; 35% was detected on day +100 surveillance PET scan. 5-year overall survival (OS) by 18F-FDG-PET scan at day +100 post-AHCT was significantly lower in D4 and D5 patients (37%; 95% confidence interval [CI], 14% to 100% versus 25%; 95% CI, 43% to 89%) compared with patients with D1 and D2 (62%; 95% CI, 43% to 89% versus 62%; 95% CI, 46% to 84%). TLG and TMTV were not prognostic. SUVmax at day +100 varied from 1.5 (D1) to 17.9 (D5). In multivariate analysis, only SUVmax was predictive of relapse and OS; mortality increased 1.8-fold with each SUVmax doubling (hazard ratio [HR], 1.8; 95% CI, 1.3 to 2.3; P < .01). At a median follow-up of 3.3 years (range, 1 to 12 years), lymphoma-related mortality was 1.8-fold higher among patients whose relapse was detected clinically (symptomatic) versus radiographically on surveillance scan (HR, 1.8; 95% CI, .9 to 3.4; P = .08). In patients with relapsed/refractory DLBCL, a routine PET imaging at day +100 post-AHCT detects asymptomatic relapse and high SUVmax identifies patients with poor expected survival of less than 1 year. Identifying this high-risk cohort can potentially highlight patients who might benefit from preemptive interventions to prevent or delay relapse.

Laryngeal Squamous Cell Carcinoma with Osteosarcomatous Differentiation and Involvement of Thyroid Cartilage Mimicking Sarcoma Arising from Thyroid Cartilage.

Basaloid squamous cell carcinoma (BSCC) with a spindle cell component of the head and neck is an uncommon entity. In this case, we present a radiology-pathology correlation of a rare laryngeal BSCC with sarcomatous transformation and osteosarcomatous differentiation involving the laryngeal cartilage, which thus mimicked clinically and radiographically osteosarcoma or chondrosarcoma with calcification. Microscopic examination revealed predominantly BSCC with extensive osseous metaplasia among sheets and nests of basaloid tumor cells. There were also small foci of osteosarcoma, undifferentiated pleomorphic sarcoma, and spindle cell carcinoma. The presence of squamous cell carcinoma (SCC) in-situ, small areas of conventional SCC and diffuse positivity of p40 in conventional and basaloid squamous components confirmed that this tumor was indeed derived from surface squamous epithelium. Awareness of the broad differentiation potentials of SCC can avoid misdiagnosis of SCCs as sarcoma. This case emphasizes the importance of radiologic-pathologic correlation in definitive diagnosis and clinical management of laryngeal malignancies.

Positron emission computed tomography and magnetic resonance imaging features of sinonasal small round blue cell tumors.

AIM: The sinonasal tract hosts numerous types of undifferentiated neoplasms, having small round cell morphology. The aim of this study was to determine whether sinonasal small round blue cell tumors (SRBCT) have distinct imaging features on computed tomography (CT), magnetic resonance imaging (MRI), and 18-fluorodeoxyglucose positron emission tomography (18F-FDG PET)/CT. METHODS: Seventy-three patients (43 male; Mage = 61.2 years) with histopathologically proven sinonasal SRBCT were retrospectively reviewed. Imaging features of SRBCTs including location, maximum dimension, margin characteristics, presence of calcification, sclerotic bone changes, intratumoral necrosis, tumor extension, bone destruction, bone remodeling, perineural spread, T1- and T2-weighted MRI signal intensity, qualitative features on diffusion-weighted imaging and 18F-FDG PET/CT, and pattern of contrast enhancement were analyzed using Fisher's exact test or the chi-square test. The maximum standardized uptake values (SUVmax) and apparent diffusion coefficient (ADCmean) values of SRBCT were compared by utilizing the Kruskal-Wallis test. RESULTS: There was a significant difference between SRBCT type regarding the tumor location (p = 0.006), 18F-FDG uptake pattern (p = 0.006), involvement of the orbit (p = 0.016) and pterygopalatine fossa (p = 0.043), the presence of perineural spread (p < 0.001), bone destruction (p = 0.034), and intratumoral necrosis (p = 0.022). Bone destruction and necrosis were more common in rhabdomyosarcoma. Perineural spread was common in sinonasal adenoid cystic carcinoma (ACC). Qualitative 18F-FDG uptake features as well as tumor location were significantly different between sinonasal ACC and sinonasal undifferentiated carcinoma. The ADCmean and SUVmax values were not statistically different between SRBCT types. CONCLUSIONS: Sinonasal SRBCTs have numerous distinct imaging features on CT, MRI, and 18F-FDG PET/CT that could be useful in the differentiation between lesions when the histopathologic diagnosis is inconclusive.

Appropriate timing of surveillance intervals with whole-body 18F-FDG PET/CT following treatment for sinonasal malignancies.

PURPOSE: To assess the ideal timing of posttreatment whole-body 18F-FDG PET/CT examination as routine surveillance to determine local recurrence (R), lymph node metastasis (LM), and distant metastasis (DM) of sinonasal malignancies and to investigate the effect of 18F-FDG PET/CT on survival. METHODS: An overall 80 patients who had undergone a total of 197 posttreatment whole-body 18F-FDG PET/CT examinations for sinonasal malignancy were retrospectively examined after institutional review board approval. Patients were grouped regarding the time intervals (<1 month, 1-3 months, 3-6 months, 6-12 months, 12-18 months and >18 months) after the conclusion of treatment. Differences in diagnostic accuracy due to different follow-up intervals were calculated by receiver operator curves (ROC) and a Cox proportional hazards model was used to assess the prognostic value of surveillance 18F-FDG PET/CT. RESULTS: Considering the time intervals of posttreatment 18F-FDG PET/CT scans, the negative predictive value and positive predictive value of the 18F-FDG PET/CT examinations to predict overall recurrence in 1-3 months (100 and 100%, respectively) and >18 months (100 and 95%, respectively) were higher than for recurrence detection in <1 month (50 and 100%, respectively), 3-6 months (81 and 93%, respectively), 6-12 months (79 and 87%, respectively), and 12-18 months (75 and 80%, respectively) (p < 0.05). Positive findings on 18F-FDG PET/CT scans were also independent predictors of poorer overall survival (OS) (p < 0.05). CONCLUSIONS: Whole-body 18F-FDG PET/CT is capable of identifying recurrences following treatment, using an optimal time interval for scanning of 1-3 months and >18 months after therapy.

"CHOICES": An acronym to aid in delineating potential causes of non-metabolic, non-infectious acute toxic leukoencephalopathy.

PURPOSE: To describe non-metabolic, non-infectious etiologies of acute toxic leukoencephalopathy (ATL) on DWI MRI, and provide a useful acronym to remember them. MATERIAL AND METHODS: Our PACS archive was reviewed, yielding 185 patients with suspected ATL per MRI reports and clinical follow up; infectious or metabolic causes were excluded. RESULT/DISCUSSION: The 87 included non-infectious, non-metabolic ATL patients' etiologies are represented by the acronym 'CHOICES': chemotherapy ('C',n = 34); heroin-induced ('H',n = 6), opioid analogues ('O',n = 14); immunosuppressant ('I',n = 11) or imidazole (n = 2); cocaine ('C',n = 1); environmental or ethanol abuse ('E',n = 5), splenial lesions ('S',n = 9), and 'other' (n = 5). CONCLUSION: The "CHOICES" acronym delineates various toxic etiologies of ATL.

Prediction of survival with combining quantitative 18 F-FDG PET/CT and DW-MRI parameters in sinonasal malignancies.

BACKGROUND: We aimed to establish the prognostic value of 18 F-fluoro-deoxy-glucose positron emission/CT (18 F-FDG PET/CT) and diffusion-weighted (DW) MRI in determining overall survival (OS), progression-free survival (PFS), and distant metastasis-free survival (DMFS) of sinonasal malignancies. METHODS: Sixty-eight patients with sinonasal cancer who underwent both pretreatment 18 F-FDG PET/CT scan and head-neck MRI from January 2009 through August 2017 were retrospectively reviewed. Kaplan-Meier survival analysis of 18 F-FDG PET/CT and DW-MRI parameters were performed for OS, PFS, and DMFS. RESULTS: Cox regression analysis determined that all the quantitative 18 F-FDG PET/CT and DW-MRI parameters were independently correlated with PFS, DMFS, and OS (P < .05). After controlling for imaging variables, perineural invasion (P = .02) and ill-defined margin (P = .02) were found to be significantly correlated with shorter OS; while the perineural invasion was significantly correlated with shorter PFS (P = .02). CONCLUSIONS: The pretreatment DW-MRI and 18 F-FDG PET/CT parameters could be substantial surrogate markers for sinonasal malignancies.