再発性甲状腺癌のリンパ節転移におけるTc-99m MDPの集積(Tc-99m MDP Accumulation in Lymph Node Metastases of Recurrent Thyroid Cancer)(英語)

金沢医科大学 放射線科原著論文/症例報

インフルエンザ カンセンショウ ニ ガッペイ シタ キュウセイ チュウスイエン ノ 2 ショウニ レイ

症例1は6歳女児.インフルエンザ感染症初日に発熱しオセルタミビルを開始.第3病日,右下腹部に限局した圧痛が出現.腹部造影CTで糞石を認め急性虫垂炎と診断.保存的に加療し炎症反応と腹痛は改善した.症例2は5歳女児.第1病日に発熱と腹痛を認め,第3病日に鼻咽腔迅速検査でインフルエンザB型と診断しザナミビル吸入を開始.触診で右下腹部に反跳痛を認め,腹部単純CTで虫垂壁の肥厚と糞石を確認.急性虫垂炎の併発と診断し,第4病日に虫垂切除術を施行.切除虫垂に膿瘍を認め腹腔ドレーンを留置.第5病日に解熱し経過は順調であった.インフルエンザに伴う腹痛では感染に付随する腹痛と断定せず急性虫垂炎の可能性も考慮し腹部CTなどの画像検査を行うことが肝要である.We report herein two pediatric cases of influenza virus infection associated with acute appendicitis. Patient 1 was a 6-year-old girl. She presented to hospital with a high fever and received oral administration of oseltamivir phosphate. On the third day from the onset, tenderness developed in the right lower area at McBurney\u27s point. Abdominal enhanced computed tomography( CT) showed intestinal fecalith, and acute appendicitis was subsequently diagnosed. Antibiotic therapy was performed, and abdominal pain and inflammation data improved. Patient 2 was a 5-year-old girl. On the first day, abdominal pain developed. On the third day from the onset, influenza type B was diagnosed using rapid antigen testing of the nasal mucosa, and inhalation therapy was started with zanamivir. Rebound tenderness was seen in the lower right abdomen. Abdominal CT showed both hypertrophy of the appendix wall and intestinal fecalith, and influenza infection associated with acute appendicitis was subsequently diagnosed. On the fourth day, appendectomy was performed. Drainage treatment was required to prevent peri-appendicitis abscess. On the fifth day, the patient defervesced and, as for the progress, was favorable. When encountering influenza infection associated with abdominal pain, performing abdominal CT is important

Advantages of L-3-[ 18 F] fluoro-alpha-methyl tyrosine over 2-[ 18 F]-fluoro-2-deoxyglucose in detecting liver metastasis during positron emission tomography scan

Abstract Purpose: We aimed to assess the usefulness of positron emission tomography (PET) using the amino acid tracer L-3-[18F] fluoro-alpha-methyl tyrosine (FAMT) in detecting metastatic liver lesions compared with 2-[18F]-fluoro-2-deoxyglucose (FDG). Methods: We included 24 patients with liver metastases who underwent both FDG-PET/computed tomography (CT) and FAMT-PET/CT. Maximum standardized uptake value (SUVmax) and tumor-to-liver parenchymal (T/L) ratio were analyzed to evaluate the correlation between FDG and FAMT uptakes in metastatic liver lesions; adenocarcinoma (AC, n = 21), squamous cell carcinoma (SCC, n = 23), neuroendocrine tumor (NET, n = 9), and carcinoid tumor (CAR, n = 6). Results: We detected 59 lesions on performing either FDG-PET or FAMT-PET. NETs had significantly lower T/L ratios for FAMT (median, 1.00; range, 0.86-1.34) compared with those for FDG (median 2.86; range 1.70-6.13, p < 0.01). CAR tumors tended to reveal lower T/L ratios for FDG (median 1.10; range 0.78-1.92) than those for FAMT (median 1.80; range 0.80-2.34). Comparison of T/L ratios of SCC and AC revealed that FAMT in the metastatic liver lesions of SCC was higher than those of AC (p < 0.05). Conclusion: FAMT-PET could detect metastatic liver lesions from various cancers, except NET

Clinical value of fluorine-18α-methyltyrosine PET in patients with gliomas: comparison with fluorine-18 fluorodeoxyglucose PET

Abstract Background We investigated the relationship between metabolic activity and histological features of gliomas using fluorine-18α-methyltyrosine (18F-FAMT) positron emission tomography (PET) compared with fluorine-18 fluorodeoxyglucose (18F-FDG) PET in 38 consecutive glioma patients. The tumor to normal brain ratios (T/N ratios) were calculated, and the relationships between T/N ratio and World Health Organization tumor grade or MIB-1 labeling index were evaluated. The diagnostic values of T/N ratios were assessed using receiver operating characteristic (ROC) curve analyses to differentiate between high-grade gliomas (HGGs) and low-grade gliomas (LGGs). Results Median T/N ratio of 18F-FAMT PET was 2.85, 4.65, and 4.09 for grade II, III, and IV gliomas, respectively, with significant differences between HGGs and LGGs (p = 0.006). Both T/N ratio (p = 0.016) and maximum standardized uptake value (p = 0.033) of 18F-FDG PET showed significant differences between HGGs and LGGs. ROC analysis yielded an optimal cut-off of 3.37 for the T/N ratio of 18F-FAMT PET to differentiate between HGGs and LGGs (sensitivity 81%, specificity 67%, accuracy 76%, area under the ROC curve 0.776). Positive predictive value was 84%, and negative predictive value was 62%. T/N ratio of 18F-FAMT PET was not correlated with MIB-1 labeling index in all gliomas, whereas T/N ratio of 18F-FDG PET was positively correlated (r s  = 0.400, p = 0.013). Significant positive correlation was observed between T/N ratios of 18F-FDG and 18F-FAMT (r s  = 0.454, p = 0.004), but median T/N ratio of 18F-FAMT PET was significantly higher than that of 18F-FDG PET in all grades of glioma. Conclusions The T/N ratio of 18F-FAMT uptake has high positive predictive value for detection of HGGs. 18F-FAMT PET had higher T/N ratio, with better tumor-normal brain contrast, compared to 18F-FDG PET in both LGGs and HGGs. Therefore, 18F-FAMT is a useful radiotracer for the preoperative visualization of gliomas

Prognostic value of metabolic tumor volume of pretreatment 18F-FAMT PET/CT in non-small cell lung Cancer

Abstract Background This study aimed to determine the prognostic value of positron emission tomography (PET) metabolic parameters—namely metabolic tumor volume (MTV), total lesion glycolysis (TLG), and total lesion retention (TLR)—on fluorine-18 (18F) fluorodeoxyglucose (FDG) and L- [3-18F]-α-methyltyrosine (18F-FAMT) PET/CT in patients with non-small-cell lung cancer (NSCLC). Methods The study group comprised 112 NSCLC patients who underwent 18F-FDG and 18F-FAMT PET/CT prior to any therapy. The MTV, TLG, TLR, and maximum standardized uptake value (SUVmax) of the primary tumors were determined. Automatic MTV measurement was performed using PET volume computer assisted reading software. (GE Healthcare). Cox proportional hazards models were built to assess the prognostic value of MTV, TLG (for 18F-FDG), TLR (for 18F-FAMT), SUVmax, T stage, N stage, M stage, clinical stage, age, sex, tumor histological subtype, and treatment method (surgery or other therapy) on overall survival (OS). Results Higher TNM, higher clinical stage, inoperable status, and higher values for all PET parameters (both 18F-FAMT and 18F-FDG PET) were significantly associated (P < 0.05) with shorter OS. Multivariate analysis revealed that a higher MTV of 18F-FAMT (hazard ratio [HR]: 2.88, CI: 1.63–5.09, P < 0.01) and advanced clinical stage (HR: 5.36, CI: 1.88–15.34, P < 0.01) were significant predictors of shorter OS. Conclusions MTV of 18F-FAMT is of prognostic value for OS in NSCLC cases and can help guide decision-making during patient management

Positron Emission Tomography/Computed Tomography before Treatment as a Predictor of 90Y-Ibritumomab Tiuxetan Response

Background and Aims: Radioimmunotherapy (RIT) appears as one of the most effective treatment options for patients with relapsed or resistant non-Hodgkin’s lymphoma (NHL).　Our aim was to evaluate the role of pre-RIT 18F-fluorodeoxyglucose- positron emission tomography╱computed tomography (FDG-PET╱CT) as an early predictor of 90Y-Ibritumomab tiuxetan treatment response.　Methods: We included consecutive 20 patients with relapsed NHL (10 males; mean age, 58.5 ± 8.9 years old) who were treated with 90Y-Ibritumomab tiuxetan.　FDG-PET╱CT was performed before and after treatment.　Semiquantitative parameters of all measurable FDG-avid lesions were measured and averaged.　A measurable FDG-avid lesion was defined as a lesion that showed FDG uptake higher than liver with a diameter more than 1 cm.　Treatment response was determined by visual assessment based on a five-point score criteria from FDGPET ╱CT after treatment.　Results: Fourteen patients (70%) were classified as responders and the other six patients (30%) as non-responders.　All semiquantitative parameters except for MTV demonstrated significantly lower values in the responders compared with the non-responders (p＜0.05).　Conclusions: Semiquantitative evaluation by SUVmax, SUVpeak, and TLG before treatment were useful as early predictors of 90Y-Ibritumomab tiuxetan treatment response