Imaging Findings of Primary Acinic Cell Carcinoma of the Breast: A Case Report.

Acinic cell carcinoma is a rare malignant tumor that accounts for 2%-3% of salivary gland tumors. Acinic cell carcinoma arising from the breast is extremely rare, with only approximately 70 cases reported to date. Owing to its rarity, previous studies have primarily focused on pathological findings. Herein, we present the clinical and radiological features of acinic cell carcinoma of the breast in a 33-year-old woman.

The Role of 18F-FDG PET/CT for Evaluation of Cervical Metastatic Lymph Nodes in a Patient with Metallic Artifacts from Dental Prosthesis: a Case Report.

Cervical metastasis of squamous cell carcinoma from an unknown primary site occurs in approximately 2-4% of head and neck tumor cases. Without identification of the primary site, proper management cannot be achieved, resulting in significant morbidity and a lower cure rate. For the primary site assessment, positron emission tomography/computed tomography (PET/CT) using the radiotracer 18F-fluorodeoxyglucose (FDG) is the imaging modality of choice and has been shown to be superior to CT alone. Here, we report a case of cervical metastasis of squamous cell carcinoma in an 82-year-old man. 18F-FDG PET/CT revealed a tongue-base lesion, although neck CT detected no lesions because of artifacts from dental prosthesis, which was suspected as the primary site. The final diagnosis was confirmed as tongue-base cancer with neck lymph node metastases through biopsy. These results suggest that 18F-FDG PET/CT is a valuable diagnostic tool in patients with cervical metastatic lymph nodes because it can demonstrate primary tumors in patients with dental prosthesis.

Head-to-head comparison of 18 F-FP-CIT and 123 I-FP-CIT for dopamine transporter imaging in patients with Parkinson's disease: A preliminary study.

123 I-FP-CIT and 18 F-FP-CIT are radiotracers which are widely used to diagnose Parkinson's disease (PD). However, to our knowledge, no studies to date have made head-to-head comparisons between 123 I-FP-CIT and 18 F-FP-CIT. Therefore, in this study, 123 I-FP-CIT SPECT/CT was compared with 18 F-FP-CIT PET/CT in the same cohort of subjects. Patients with PD and essential tremor (ET) underwent 123 I-FP-CIT SPECT/CT and 18 F-FP-CIT PET/CT. Visual and semiquantitative analyses were conducted. The specific binding ratio (SBR) and putamen to caudate ratio (PCR) were compared between subjects who underwent 123 I-FP-CIT SPECT/CT and 18 F-FP-CIT PET/CT. Visual analysis showed that the striatal uptake of both radiotracers was decreased in the PD group, whereas striatal uptake was intact in the ET group. The SBR between 123 I-FP-CIT SPECT/CT and 18 F-FP-CIT PET/CT showed a positive correlation (r = .78, p < .01). However, the mean SBRs on 18 F-FP-CIT PET/CT were higher than those on 123 I-FP-CIT SPECT/CT (2.19 ± .87 and 1.22 ± .49, respectively; p < .01). The PCRs in these two modalities were correlated with each other (r = .71, p < .01). The mean PCRs on 18 F-FP-CIT PET/CT were not significantly higher than those on 123 I-FP-CIT SPECT/CT (1.31 ± .19 and 0.98 ± .06, respectively; p = .06). These preliminary results indicate that the uptake of both 123 I-FP-CIT and 18 F-FP-CIT was decreased in the PD group when compared with the ET controls. Visual analyses using both methods did not affect the diagnostic accuracy in this study. However, semiquantitative analysis indicated a better contrast of 18 F-FP-CIT PET/CT relative to 123 I-FP-CIT SPECT/CT.

The Role of (18)F-FDG PET/CT as a Prognostic Factor in Patients with Synovial Sarcoma.

PURPOSE: This research aims to investigate the potential of (18)F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET) to predict pathologic response after neoadjuvant chemotherapy (NAC) and overall survival (OS) of patients with synovial sarcoma in Korea. METHODS: Twenty patients with synovial sarcoma from January 2001 to December 2011 were reviewed retrospectively. All patients underwent pre-treatment FDG PET and tumor removal. Patients were classified with the maximum SUV (SUVmax), metabolic tumor volume (MTV), total lesion glycolysis (TLG), age, sex, histologic subtype, tumor size, NAC, resection margin, and metastasis at diagnosis. Pathologic response was assessed using the French Federation of Cancer Centers system. Statistical analyses were analyzed using the Kaplan-Meier method, log-rank test, Cox proportional hazards regression model, and Mann-Whitney test. RESULTS: Nine patients (45 %) showed pathologic response, and ten patients survived. Higher SUVmax, higher MTV, higher TLG, monophasic epithelial type, and metastasis at diagnosis were significantly related to poorer OS (p = 0.047, 0.016, 0.016, 0.045, and 0.018, respectively). By multivariate analysis, metastasis at diagnosis was significantly related to poorer OS (p = 0.012/HR = 5.9, 95 % CI 1.47 to 24.1). The SUVmax, MTV, and TLG of the non-responder group were significantly higher than those of the responder group (p = 0.020, 0.020, and 0.020, respectively). There was no significant difference in size between the two groups (p = 0.062). CONCLUSIONS: A higher SUVmax on the pre-treatment scan, monophasic epithelial type, and metastasis at diagnosis were significantly associated with a poorer OS, and pathologic responders showed a higher SUVmax before NAC. The PET parameters can be used to predict OS and pathologic response in patients with synovial sarcomas before NAC.

Prognostic significance of pretreatment ¹8F-FDG PET/CT in patients with relapsed/refractory B-cell non-Hodgkin's lymphoma treated by radioimmunotherapy using ¹³¹I-rituximab.

AIMS: It was the aim of this paper to identify prognostic factors in patients with relapsed or refractory B-cell non-Hodgkin's lymphomas, treated by radioimmunotherapy (RIT) with radioiodinated human/murine chimeric anti-CD20 monoclonal antibody rituximab (¹³¹I-rituximab). METHODS: Twenty-four patients were enrolled prospectively and were treated with unlabeled rituximab 70 mg and a therapeutic activity (median 7.3 GBq) of ¹³¹I-rituximab. Contrast-enhanced ¹8F-FDG PET/CT scans were performed before and after 1 month of RIT. Tumor sizes and maximum standardized uptake values (SUVmax) of scans were measured. RESULTS: Four of the 24 patients survived. High SUVmax in a pretreatment scan was found to be related to poorer overall survival (OS) and progression-free survival (p = 0.04 and 0.02, respectively). Furthermore, a large tumor size in a pretreatment scan was associated with poorer OS but not with progression-free survival (p < 0.01 and p = 0.07, respectively). By multivariate analyses, a high SUVmax, a large tumor size in a pretreatment scan and diffuse large B-cell lymphoma histology were significantly associated with poorer OS [p = 0.04/hazard ratio (HR) = 3.54, p < 0.01/HR = 5.52, and p = 0.02/HR = 3.38, respectively). CONCLUSION: SUVmax and tumor size determined by a pretreatment ¹8F-FDG PET/CT result as significant predictors of OS in patients with relapsed or refractory B-cell non-Hodgkin's lymphoma treated by RIT.

Evaluation of Adrenal Masses in Lung Cancer Patients Using F-18 FDG PET/CT.

PURPOSE: The aim of this study was to assess the diagnostic efficacy of PET/CT using various parameters for the characterization of adrenal nodules in lung cancer patients. METHODS: Sixty-one adrenal nodules in 51 lung cancer patients were evaluated. The final diagnosis was based on histology (n = 2) or imaging follow-up (n = 59, range of follow-up: 7-57 months, median 27 months). Each adrenal nodule was analyzed using four parameters of PET/CT: the maximum standardized uptake value (SUVmax), the adrenal nodule/liver ratio of the SUV (SUV ratio), Hounsfield units (HU) and size. The optimal cutoff of each parameter for the identification of metastatic nodule was determined by ROC analysis and then the diagnostic efficacy was compared among the parameters. RESULTS: Of the 61 adrenal nodules, 45 (73%) were considered metastasis. The optimal cutoff values of the parameters were SUVmax >2.7, SUV ratio >1.3, HU >18 and size >20 mm, respectively. The sensitivity, specificity and accuracy by SUVmax >2.7 were 88.9%, 87.5% and 88.5%, and those by SUV ratio >1.3 were 84.4%, 100% and 88.5%, respectively. The combination of SUV ratio >1.3 and HU >18 had sensitivity of 97.7%, specificity of 81.2% and accuracy of 93.4% to predict adrenal metastasis in patients with lung cancer. CONCLUSION: SUV ratio from F-18 FDG PET/CT could identify the adrenal metastasis in lung cancer patients. The combination of SUV ratio and HU can improve the accuracy of differentiating benign and metastatic adrenal lesions in lung cancer patients.

The Prevalence and Characteristics of Brown Adipose Tissue in an (18)F-FDG PET Study of Koreans.

PURPOSE: The object of this study was to evaluate the prevalence and characteristics of brown adipose tissue (BAT) in Korean subjects using (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET). METHODS: Six thousand and five consecutive (18)F-FDG PET/CT scans of 5,115 patients (3,007 females and 2,108 males, mean age 53.5 years) were retrospectively reviewed. We characterized the nature of BAT, such as its location, and we assessed the influence of sex, age, body mass index (BMI), and temperature on BAT. RESULTS: The prevalence of BAT in Koreans in a single (18)F-FDG PET/CT scan in average conditions was 1.07%. The BAT detection rate was higher in females than males (1.32% vs 0.73%), and also with younger age (7.94% vs 0.73%), lower BMI (BMI with BAT, 21.1 vs BMI without BAT, 23.15) and cold outdoor temperature (1.65% vs 0.49%). The most frequent location of BAT was the supraclavicular area (left, 0.91%; right, 0.88%) and ventral neck area (left, 0.62%; right, 0.63%). CONCLUSIONS: The characteristics of BAT in Koreans are not different from those described for Caucasians. However, the low prevalence of BAT in our study might be related to some scan condition like ambient temperature, but further study is needed.