Yoriko Kajiya

FDG PET/CT and diffusion-weighted imaging for breast cancer: prognostic value of maximum standardized uptake values and apparent diffusion coefficient values of the primary lesion

PurposeTo correlate both primary lesion 18F-fluorodeoxyglucose (FDG) maximum standardized uptake value (SUVmax) and diffusion-weighted imaging (DWI) apparent diffusion coefficient (ADC) with clinicopathological prognostic factors and compare the prognostic value of these indexes in breast cancer.MethodsThe study population consisted of 44 patients with 44 breast cancers visible on both preoperative FDG PET/CT and DWI images. The breast cancers included 9 ductal carcinoma in situ (DCIS) and 35 invasive ductal carcinomas (IDC). The relationships between both SUVmax and ADC and clinicopathological prognostic factors were evaluated by univariate and multivariate regression analysis and the degree of correlation was determined by Spearman’s rank test. The patients were divided into a better prognosis group (n = 24) and a worse prognosis group (n = 20) based upon invasiveness (DCIS or IDC) and upon their prognostic group (good, moderate or poor) determined from the modified Nottingham prognostic index. Their prognostic values were examined by receiver operating characteristic analysis.ResultsBoth SUVmax and ADC were significantly associated (p<0.05) with histological grade (independently), nodal status and vascular invasion. Significant associations were also noted between SUVmax and tumour size (independently), oestrogen receptor status and human epidermal growth factor receptor-2 status, and between ADC and invasiveness. SUVmax and ADC were negatively correlated (ρ=−0.486, p = 0.001) and positively and negatively associated with increasing of histological grade, respectively. The threshold values for predicting a worse prognosis were ≥4.2 for SUVmax (with a sensitivity, specificity and accuracy of 80%, 75% and 77%, respectively) and ≤0.98 for ADC (with a sensitivity, specificity and accuracy of 90%, 67% and 77%, respectively).ConclusionSUVmax and ADC correlated with several of pathological prognostic factors and both indexes may have the same potential for predicting the prognosis of breast cancer.

FDG PET/CT and diffusion-weighted imaging of head and neck squamous cell carcinoma: comparison of prognostic significance between primary tumor standardized uptake value and apparent diffusion coefficient.

Purpose: To compare primary tumor 18F-fluorodeoxyglucose (FDG) maximum standardized uptake value (SUVmax) and diffusion-weighted imaging (DWI) apparent diffusion coefficient (ADC) obtained in the same patients with head and neck squamous cell carcinoma (HNSCC) to clarify the prognostic significance of both indexes. Materials and Methods: The study population comprised 26 patients with HNSCC visible on both pretreatment FDG PET/CT and DWI. Correlation between SUVmax and ADC (b values; 0 and 800 seconds/mm2) was analyzed by the Spearmans rank test. Disease-free survival (DFS) was calculated by the Kaplan-Meier method. Prognostic significance was assessed by the long-rank test and Cox proportional hazards analysis. Results: SUVmax and ADC correlated significantly and negatively (&rgr; = −0.566, P = 0.005). High (>12.1) SUVmax (P < 0.001), low (⩽0.88) ADC (P = 0.009), high (T3–4) T stage (P = 0.030), and high (N2–3) N stage (P = 0.007) were significant in predicting poor 2-year DFS. The accuracy for predicting disease events was 81% (21/26) for SUVmax (>12.1) and 73% (19/26) for ADC(⩽0.88) without significant difference between them (P = 0.52). Disease event hazards ratios for significant unadjusted SUVmax (P = 0.015) and ADC (P = 0.039) remained significant when adjusted for other dichotomized clinical covariates (SUVmax; P = 0.009–0.039, ADC; P = 0.017–0.037) except SUVmax for ADC and ADC for SUVmax and T stage. Conclusion: These results suggest that pretreatment primary tumor SUVmax and ADC correlate significantly and negatively and both may have similar potential to predict DFS or disease events of HNSCC.

18FDG PET for grading malignancy in thymic epithelial tumors: Significant differences in 18FDG uptake and expression of glucose transporter-1 and hexokinase II between low and high-risk tumors: Preliminary study

PURPOSE To evaluate (18)F-fluorodeoxyglucose (FDG) uptake to predict the malignant nature and analyze the correlation between FDG uptake and expression of glucose transporter 1 (Glut-1) and hexokinase II (HK-II) in thymic epithelial tumors. MATERIALS AND METHODS Eleven patients with a thymic epithelial tumor who underwent FDG PET/CT before therapy were reviewed. The thymic tumors were classified by the WHO histological classification and Masaoka clinical staging. Comparison of maximum standardized uptake value (SUV(max)) of the lesion was made between the low-risk (Type A, AB and B1) and high-risk {Type B2, B3 and C (thymic cancer)} groups and among clinical stages. Expression of Glut-1 and HK-II was analyzed immunohistochemically. RESULTS All 11 tumors showed FDG uptake visually. SUV(max) was significantly higher in the high-risk group (n=5, 5.24 ± 2.44) than the low-risk group (n=6, 3.05 ± 0.55) (P=0.008). Staining scores of both Glut-1 and HK-II were significantly higher in the high-risk group than in the low-risk group (Glut1: P=0.034 and HK-II: P=0.036). There were no significant differences in SUV(max) (P=0.11), Glut-1 (P=0.35) and HK-II scores (P=0.29) among clinical stages. SUV(max) was significantly correlated to each of the staining scores of Glut-1 (ρ=0.68, P=0.031) and HK-II (ρ=0.72, P=0.024). CONCLUSION These preliminary results support the previously published view that SUV(max) may be useful to predict the malignant nature of thymic epitherial tumors and suggest that the degree of FDG uptake in the thymic epitherial tumors is closely related to the amount of Glut-1 and HK-II in the tumor.

Diagnosis of Metastases from Postoperative Differentiated Thyroid Cancer: Comparison between FDG and FLT PET/CT Studies

PURPOSE To compare positron emission tomography (PET)/computed tomography (CT) studies performed with the glucose analog fluorine 18 ((18)F) fluorodeoxyglucose (FDG) and the cell proliferation tracer (18)F fluorothymidine (FLT) in the diagnosis of metastases from postoperative differentiated thyroid cancer. MATERIALS AND METHODS The institutional ethics review board approved this prospective study. From March 2010 to February 2012, 20 patients (mean age, 53 years; age range, 22-79 years) with postoperative differentiated thyroid cancer underwent both FDG and FLT PET/CT as a staging work-up before radioiodine therapy. In each patient, 28 anatomic areas were set and analyzed for lymph node and distant metastases. The McNemar exact or χ(2) test was used to examine differences in diagnostic indexes in the detection of lymph node and distant metastases between both tracer PET/CT studies. RESULTS There were 34 lymph node metastases and/or 73 distant metastases (70 metastases in lung and one each in bone, nasopharynx, and brain) in 13 patients. At patient-based analysis, the sensitivity, specificity, and accuracy were 92% (12 of 13 patients), 86% (six of seven patients), and 90% (18 of 20 patients), respectively, for FDG PET/CT and 69% (nine of 13 patients), 29% (two of seven patients), and 55% (11 of 20 patients) for FLT PET/CT. The accuracy of FDG PET/CT was significantly better than that of FLT PET/CT (P = .023). At lesion-based analysis, the sensitivity, specificity, and accuracy for diagnosing lymph node metastases were 85% (29 of 34 lesions), 99.6% (245 of 246 lesions), and 97.9% (274 of 280 lesions), respectively, for FDG PET/CT and 50% (17 of 34 lesions), 90.7% (223 of 246 lesions), and 85.7% (240 of 280 lesions) for FLT PET/CT. The sensitivity, specificity, and accuracy for diagnosing distant metastases were 45% (33 of 73 lesions), 100% (207 of 207 lesions), and 85.7% (240 of 280 lesions), respectively, for FDG PET/CT and 6.8% (five of 73 lesions), 100% (207 of 207 lesions), and 75.7% (212 of 280 lesions) for FLT PET/CT. The sensitivity (P = .002), specificity (P < .001), and accuracy (P < .001) of FDG PET/CT in the diagnosis of lymph node metastases were superior to those of FLT PET, as were the sensitivity (P < .001) and accuracy (P < .001) in the diagnosis of distant metastases. CONCLUSION FDG PET/CT is superior to FLT PET/CT in the diagnosis of postoperative differentiated thyroid cancer lymph node and distant metastases. Thus, FDG PET/CT is more suitable than FLT PET/CT for examining recurrence of postoperative differentiated thyroid cancer.

Clinical Significance of 18F-fluorodeoxyglucose Positron Emission Tomography in Superficial Esophageal Squamous Cell Carcinoma

PurposeTo assess the clinical usefulness and significance of 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) in superficial esophageal squamous cell carcinoma (ESCC).MethodsWe examined FDG-PET for 80 consecutive patients with superficial ESCC without neoadjuvant treatment. Fifty-seven patients underwent radical esophagectomy, and 23 patients received endoscopic resection. The FDG uptake index was evaluated with clinicopathological findings, and glucose transporter 1 (Glut-1) expression in primary tumors was examined immunohistochemically.ResultsThe FDG uptake in primary tumors correlated with histology, depth of tumor invasion, lymph node metastasis, lymphatic invasion, vascular invasion, and Glut-1 expression. All patients with more than 4.4 maximum standardized uptake value (SUVmax) had deeper invasion of submucosa. Among 16 patients with lymph node metastasis, only two were found to have lymph node metastasis. FDG uptake, depth of tumor invasion, lymph node metastasis, and histology were found to be prognostic factors, and histology was an independent prognostic factor. In FDG uptake–positive patients, depth of tumor invasion and histology were prognostic factors.ConclusionsFDG-PET is useful for diagnosing tumors with deeper invasion of submucosa and is helpful in making decisions regarding endoscopic treatment for superficial ESCC. Patients with FDG uptake–positive disease, deeper invasion of submucosa, poorly differentiated tumor, and poor prognosis should receive multimodal treatment.

Age-related changes in cerebral MR angiography

Two hundred forty four neurologically normal subjects (118 males and 126 females, aged 7 to 82 yrs.) were evaluated to assess the correlation of the degree of visualization of cerebral arteries on magnetic resonance angiography (MRA) with aging, sex, laterality or lacunar infarctions on magnetic resonance imaging (MRI). A single volume three-dimensional transformation time-of-flight pulse sequence with slab thickness of 115 mm was used to obtain axial, saggital and coronal projection images. A total of 6 arteries including bilateral anterior cerebral arteries (ACAs), middle cerebral arteries (MCAs) and posterior cerebral arteries (PCAs) for every subject were each graded into 8 scores by the degree of visualization of the arteries. Results show that an age-related decline of visualization of the cerebral arteries in ACA (r = -0.603, p < 0.001), MCA (r = -0.452, p < 0.001) and PCA (r = -0.537, p < 0.001). The arteries were better visualized in females than males during the fifth decade (p < 0.01). No substantial relationship was observed between the visualization and sex in the other decades, laterality or lacunar infarctions. Thus, the cerebral MRA showed an age-related decline of visualization of the arteries and a sex-difference of the visualization in the fifth decade, probably due to the decline of the blood flow velocity with aging and a difference in it between females and males in the fifth decade.

Imaging discrepancies between magnetic resonance imaging and brain perfusion single-photon emission computed tomography in the diagnosis of Alzheimer's disease, and verification with amyloid positron emission tomography.

In the diagnosis of Alzheimers disease (AD), discrepancies are often observed between magnetic resonance imaging (MRI) and brain perfusion single‐photon emission computed tomography (SPECT) findings. MRI, brain perfusion SPECT, and amyloid positron emission tomography (PET) findings were compared in patients with mild cognitive impairment or early AD to clarify the discrepancies between imaging modalities.

High FDG and low FLT uptake in a thyroid papillary carcinoma incidentally discovered by FDG PET/CT.

We report a 58-year-old man whose incidentally discovered papillary thyroid carcinoma in the left lobe showed high FDG and low FLT uptake on PET/CT. The SUVmax was 19.7 for FDG and 3.0 for FLT. The Ki-67 labeling index of the tumor was 1.9%. Thus, the low FLT uptake might be attributed to the low proliferative activity of this cancer.

FDG-PET/CT finding of benign metastasizing leiomyoma of the lung

We report a case of multiple benign metastasizing leiomyoma (BML) lung nodules showing faint or non-avid uptake of F-18 fluorodeoxyglucose (FDG) (respective 1-hour early and 2-hour delayed maximum standardized uptake values; 1.3 or less and 1.2 or less) in a 50-year-old woman with a history of hysterectomy for uterine leiomyoma at the age of 38 years. When multiple lung nodules show faint or non-avid FDG uptake in a patient with a history of hysterectomy for uterine leiomyoma, BML should be included in the differential diagnosis.

Combined assessment of serum folate and hemoglobin as biomarkers of brain amyloid ß accumulation.

A relationship between Alzheimers disease (AD) and folate has been reported. Amyloid positron emission tomography (PET) is currently one of the most reliable biomarkers for AD. We investigated the correlation between serum folate levels and amyloid imaging to clarify whether serum folate could be a biomarker for AD. We also examined the usefulness of a combined assessment of serum folate levels and red blood cell hemoglobin content. Apolipoprotein E (APOE) gene polymorphisms were also assessed. Serum folate levels and hemoglobin content were evaluated by receiver operating characteristic analysis for their diagnostic capability as AD biomarkers relating to brain amyloid β accumulation. The area under the ROC curve (AUC) for serum folate was 0.136 (95% confidence interval [CI]: 0.000–0.312; p = 0.016). The AUC for hemoglobin content was 0.848 (95% CI: 0.661–1.000; p = 0.021). Therefore, the folate deficiency with low folate levels or the non-anaemia with high hemoglobin content levels were found to have a high probability of also testing positive for amyloid. Furthermore, eight patients were found to be folate deficiency and non-anaemia, those who were consist of 7 amyloid positive patients (87.5%), and only one of the amyloid negative patients (12.5%). These results suggest that a deficiency of serum folate and high hemoglobin levels may reflect an increased risk of amyloid β accumulation in the brain. Additionally, we demonstrated that these biomarkers could enhance the effectiveness of APOE as an AD biomarker. This study reveals that the combined assessment of serum folate levels and red blood cell hemoglobin content may be a useful biomarker for amyloid β accumulation in the brain. We also found that the combination of serum folate levels and hemoglobin content is a more specific and sensitive blood biomarker for AD than APOE or folate alone. These findings may be used to support clinical diagnosis of AD using a simple blood test.