Yemi Kim

Intratumoral metabolic heterogeneity predicts invasive components in breast ductal carcinoma in situ

AbstractObjectivesThis study investigated whether texture-based imaging parameters could identify invasive components of ductal carcinoma in situ (DCIS).MethodsWe enrolled 65 biopsy-confirmed DCIS patients (62 unilateral, 3 bilateral) who underwent 18 F-FDG PET, diffusion-weighted imaging (DWI), or breast-specific gamma imaging (BSGI). We measured SUVmax and intratumoral metabolic heterogeneity by the area under the curve (AUC) of cumulative SUV histograms (CSH) on PET, tumour-to-normal ratio (TNR) and coefficient of variation (COV) as an index of heterogeneity on BSGI, minimum ADC (ADCmin) and ADC difference (ADCdiff) as an index of heterogeneity on DWI. After surgery, final pathology was categorized as pure-DCIS (DCIS-P), DCIS with microinvasion (DCIS-MI), or invasive ductal carcinoma (IDC). Clinicopathologic features of DCIS were correlated with final classification.ResultsFinal pathology confirmed 44 DCIS-P, 14 DCIS-MI, and 10 IDC. The invasive component of DCIS was significantly correlated with higher SUVmax (p = 0.017) and lower AUC-CSH (p < 0.001) on PET, higher TNR (p = 0.008) and COV (p = 0.035) on BSGI, lower ADCmin (p = 0.016) and higher ADCdiff (p = 0.009) on DWI, and larger pathologic size (p = 0.018). On multiple regression analysis, AUC-CSH was the only significant predictor of invasive components (p = 0.044).ConclusionsThe intratumoral metabolic heterogeneity of 18 F-FDG PET was the most important predictor of invasive components of DCIS.Key Points• Preoperative identification of invasion in DCIS is important for axillary nodal management • Higher SUVmaxand lower AUC-CSH from FDG PET may indicate invasive components of DCIS • Higher TNR and COV from BSGI may indicate invasive components of DCIS • Lower ADCminand higher ADCdifffrom DWI may indicate invasive components of DCIS • AUC-CSH, an index of metabolic heterogeneity, is an independent predictor for invasive components

Background 99mTc-methoxyisobutylisonitrile uptake of breast-specific gamma imaging in relation to background parenchymal enhancement in magnetic resonance imaging.

AbstractObjectivesThis study investigated factors that could affect background uptake of 99mTc- methoxyisobutylisonitrile (MIBI) on normal breast by breast-specific gamma imaging (BSGI). In addition, the impact of background 99mTc-MIBI uptake on the diagnostic performance of BSGI was further investigated.MethodsOne hundred forty-five women with unilateral breast cancer who underwent BSGI, MRI, and mammography were retrospectively enrolled. Background uptake on BSGI was evaluated qualitatively and quantitatively. Patients were classified into non-dense and dense breast groups according to mammographic breast density. Background parenchymal enhancement (BPE) was rated according to BI-RADS classification. The relationship of age, menopausal status, mammographic breast density, and BPE with background 99mTc-MIBI uptake was analyzed.ResultsHeterogeneous texture and high background uptake ratio on BSGI were significantly correlated with younger age (p < 0.001, respectively), premenopausal status (p < 0.001 and p = 0.003), dense breast (p < 0.001, respectively), and marked BPE (p < 0.001, respectively). On multivariate analysis, only BPE remained a significant factor for background MIBI uptake (p < 0.001).There was a significant reduction in positive predictive value (p = 0.024 and p = 0.002) as background MIBI uptake and BPE grade increased.ConclusionsBPE on MRI was the most important factor for background MIBI uptake on BSGI. High background MIBI uptake or marked BPE can diminish the diagnostic performance of BSGI.Key Points• Age, menopause, density, and background parenchymal enhancement affect background MIBI uptake. • BPE is an independent factor for background MIBI uptake on BSGI. • Marked BPE may impair BSGI interpretation.

Proximity of Posterior Teeth to the Maxillary Sinus and Buccal Bone Thickness: A Biometric Assessment Using Cone-beam Computed Tomography

INTRODUCTION The aims of this study were to evaluate the vertical and horizontal relationships between the maxillary sinus floor (MSF) and the root apices of maxillary posterior teeth with various root configurations and the distance from the root apex to the MSF and the buccal cortical plate. METHODS Serial axial, coronal, sagittal, and paraxial cone-beam computed tomographic images of 132 Korean patients with fully erupted bilateral maxillary posterior teeth were analyzed. The vertical and horizontal relationships between the roots of maxillary posterior teeth and the MSF were determined. Distances from the apex to the MSF and the buccal bone plate were measured. The data were correlated with age, sex, side, and tooth type. RESULTS In total, 2159 apices in 1056 teeth were evaluated. For the vertical relationships, the frequency in group 1, in which a root apex protruded into the MSF, significantly increased toward the posterior (first premolars: 1.5%, second premolars: 14.8%, first molars: 40.5%, second molars: 44.7%, P < .001). The apices of the mesiobuccal roots of the second molars were found frequently in group 1 (35.8%) and had the shortest mean vertical distance to the MSF (0.18 mm) and the thickest mean horizontal distance to the buccal cortical plate (4.99 mm) among buccal roots of 3-rooted molars (P < .001). The frequency of group 1 differed significantly by age (P < .05). No statistically significant difference was found in sex or side analysis. For the horizontal relationship between the molar roots and the MSF, most teeth were in group BP, in which the lowest point of the MSF was located centrally, relative to the roots (94.3% for first molars, 81.0% for second molars). For the first molars, no significant difference according to sex or side was found. However, the right side (P = .003) and males (P = .005) showed higher incidences for second molars. CONCLUSIONS The data in this study highlight the close proximity between the root apex of maxillary posterior teeth and the MSF and provide estimated distances from the root apex to the buccal cortical plate. Special care must be taken in treatment planning in the maxillary posterior region.

Background Intestinal 18F-FDG Uptake Is Related to Serum Lipid Profile and Obesity in Breast Cancer Patients

Background This study investigated the relationships between background intestinal uptake on 18F–FDG PET and cardio-metabolic risk (CMR) factors. Methods A total of 326 female patients that underwent 18F–FDG PET to determine the initial stage of breast cancer were enrolled. None of the patients had history of diabetes or hypertension. The background intestinal uptake on PET was visually graded (low vs. high uptake group) and quantitatively measured using the maximal standardized uptake value (SUVmax). SUVmax of 7 bowel segments (duodenum, jejunum, ileum, cecum, hepatic flexure, splenic flexure, and descending colon-sigmoid junction) were averaged for the total bowel (TB SUVmax). Age, body mass index (BMI), fasting blood glucose level (BST), triglyceride (TG), cholesterol, high density lipoprotein (HDL), and low density lipoprotein (LDL) were the considered CMR factors. The relationships between background intestinal 18F–FDG uptake on PET and diverse CMR factors were analyzed. Results The visual grades based on background intestinal 18F–FDG uptake classified 100 (30.7%) patients into the low uptake group, while 226 (69.3%) were classified into the high uptake group. Among CMR factors, age (p = 0.004), BMI (p<0.001), and TG (p<0.001) were significantly different according to visual grade of background intestinal 18F–FDG uptake. Quantitative TB SUVmax showed significant positive correlation with age (r = 0.203, p<0.001), BMI (r = 0.373, p<0.001), TG (r = 0.338, p<0.001), cholesterol (r = 0.148, p = 0.008), and LDL (r = 0.143, p = 0.024) and significant negative correlation with HDL (r = -0.147, p = 0.022). Multivariate analysis indicated that BMI and TG were independent factors in both visually graded background intestinal 18F–FDG uptake (p = 0.027 and p = 0.023, respectively) and quantitatively measured TB SUVmax (p = 0.006 and p = 0.004, respectively). Conclusion Increased background intestinal 18F–FDG uptake on PET may suggest alteration of lipid metabolism and risk of cardio-metabolic disease in non-diabetic and non-hypertensive breast cancer patients.

Axillary Lymph Node-to-Primary Tumor Standard Uptake Value Ratio on Preoperative 18F-FDG PET/CT: A Prognostic Factor for Invasive Ductal Breast Cancer

Purpose This study assessed the axillary lymph node (ALN)-to-primary tumor maximum standard uptake value (SUVmax) ratio (ALN/T SUV ratio) in invasive ductal breast cancer (IDC) on preoperative 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) to determine the effectiveness in predicting recurrence-free survival (RFS). Methods One hundred nineteen IDC patients (mean age, 50.5±10.5 years) with pathologically proven ALN involvement without distant metastasis and preoperative FDG PET/CT were enrolled in the study. SUVmax values of the ALN and primary tumor were obtained on FDG PET/CT, and ALN/T SUV ratio was calculated. Several factors were evaluated for their effectiveness in predicting RFS. These included several parameters on FDG PET/CT as well as several clinicopathological parameters: pathologic tumor/node stage; nuclear and histological grade; hormonal state; status with respect to human epidermal growth factor receptor 2, mindbomb E3 ubiquitin protein ligase 1 (MIB-1), and p53; primary tumor size; and ALN size. Results Among 119 patients with breast cancer, 17 patients (14.3%) experienced relapse during follow-up (mean follow-up, 28.4 months). The ALN/T SUV ratio of the group with disease recurrence was higher than that of the group without recurrence (0.97±1.60 and 0.45±0.40, respectively, p=0.005). Univariate analysis showed that the primary tumor SUVmax, ALN SUVmax, ALN/T SUV ratio, ALN status, nuclear and histological grade, estrogen receptor (ER) status, and MIB-1 status were predictors for RFS. Among these variables, ALN/T SUV ratio with hazard ratio of 4.20 (95% confidence interval [CI], 1.74-10.13) and ER status with hazard ratio of 4.33 (95% CI, 1.06-17.71) were predictors for RFS according to multivariate analysis (p=0.002 and p=0.042, respectively). Conclusion Our study demonstrated that ALN/T SUV ratio together with ER status was an independent factor for predicting relapse in IDC with metastatic ALN. ALN/T SUV ratio on preoperative FDG PET/CT may be a useful marker for selecting IDC patients that need adjunct treatment to prevent recurrence.

Utility of 18F-fluorodeoxy glucose and 18F-sodium fluoride positron emission tomography/computed tomography in the diagnosis of medication-related osteonecrosis of the jaw: A preclinical study in a rat model

PURPOSE The aim of this study was to determine the clinical utility of positron emission tomography/computed tomography (PET/CT) using 18F-FDG and 18F-NaF for the diagnosis of osteonecrosis of the jaw (ONJ), by observing characteristics in rat models treated with zoledronic acid (ZA) and/or dexamethasone (DX) followed by tooth extraction. MATERIAL AND METHODS A total of 48 rats were divided randomly into four groups: Group 1, rats treated with ZA and DX; Group 2, rats treated with ZA; Group 3, rats treated with DX; and Group 4, rats treated with vehicle as normal controls. They underwent examinations with both 18F-FDG and 18F-NaF PET/CT at 4 weeks prior to tooth extraction (baseline) and 4 weeks after tooth extraction. Rats were then sacrificed to evaluate the histological incidence and characteristics of ONJ. Histological and radiological characteristics of all groups were compared to assess the effects of medication and tooth extraction. RESULTS Baseline PET/CT studies using 18F-FDG and 18F-NaF showed no difference in uptake among the groups. However, 18F-FDG PET/CT performed at 4 weeks after tooth extraction showed increased glucose metabolism at the extraction site in both the ZA/DX and the ZA-only groups compared with that in the vehicle-treated group, in accordance with the higher incidence of histological ONJ (p < 0.05, respectively). 18F-NaF PET/CT performed at 4 weeks after tooth extraction showed decreased bone uptake in the extraction site in the ZA/DX, ZA, and DX groups versus the vehicle group (all p < 0.05), but this was not correlated with the incidence of histological ONJ. The incidence of ONJ was highest in the ZA/DX group (66.7%), followed by the ZA group, both of which were significantly higher than in the DX and vehicle groups (both p < 0.05). CONCLUSIONS 18F-FDG PET/CT as an inflammatory marker appeared to be a more appropriate imaging modality than 18F-NaF PET/CT in diagnosing ONJ in a rat model including a ZA/DX group. However, the decreased bone remodeling tendency highlighted by 18F-NaF PET/CT may be an indicator of a possible risk of ONJ before the onset of clinical signs and symptoms.