Clinical practice guidelines for high-resolution breast PET, 2019 edition.

Breast positron emission tomography (PET) has had insurance coverage when performed with conventional whole-body PET in Japan since 2013. Together with whole-body PET, accurate examination of breast cancer and diagnosis of metastatic disease are possible, and are expected to contribute significantly to its treatment planning. To facilitate a safer, smoother, and more appropriate examination, the Japanese Society of Nuclear Medicine published the first edition of practice guidelines for high-resolution breast PET in 2013. Subsequently, new types of breast PET have been developed and their clinical usefulness clarified. Therefore, the guidelines for breast PET were revised in 2019. This article updates readers as to what is new in the second edition. This edition supports two different types of breast PET depending on the placement of the detector: the opposite-type (positron emission mammography; PEM) and the ring-shaped type (dedicated breast PET; dbPET), providing an overview of these scanners and appropriate imaging methods, their clinical applications, and future prospects. The name "dedicated breast PET" from the first edition is widely used to refer to ring-shaped type breast PET. In this edition, "breast PET" has been defined as a term that refers to both opposite- and ring-shaped devices. Up-to-date breast PET practice guidelines would help provide useful information for evidence-based breast imaging.

Nuclear medicine practice in Japan: a report of the eighth nationwide survey in 2017.

OBJECTIVE: Subcommittee on Survey of Nuclear Medicine Practice in Japan has performed a nationwide survey of nuclear medicine practice every 5 years since 1982 to survey contemporary nuclear medicine practice and its changes over the years. METHODS: The subcommittee sent questionnaires, including the number and category of examinations as well as the kind and dose of the radiopharmaceuticals during the 30 days of June 2017, to all nuclear medicine institutes. The total numbers for the year 2017 were then estimated. RESULTS: A total of 1132 institutes responded to the survey, including 351 PET centers. The recovery rate was 90.6%. The number of gamma cameras installed was 1332 in total, with 7.0% decrease in 5 years. Dual-head cameras and hybrid SPECT/CT scanners accounted for 88.2 and 23.6%, respectively. The number of single-photon tracer studies in 2017 was 1.08 million which means a decrease in 5.7% in 5 years and 23.6% in 10 years. All but neurotransmitter system, sentinel lymph node, and liver scintigraphy decreased. Bone scintigraphy was a leading examination (32.3%), followed by myocardial scintigraphy (24.1%) and cerebral perfusion study (18.0%) in order. SPECT studies showed an increase from 47.2% to 63.5%. PET centers have also increased from 295 to 389, as compared to the last survey. The 112 PET centers have installed one or two in-house cyclotrons. PET studies showed 24.5% increase in 5 years, with oncology accounting for 88.9%. 18F-FDG accounted for 98.2% (630,570 examinations). PET examinations using 11C-methionine have decreased, with 2440 examinations in 2017. PET examinations using 13N-NH3 have been increasing, with 2363 examinations in 2017. The number of PET studies using 11C-PIB was 904. 131I-radioiodine targeted therapies showed an increase in 5 years (23.1%), including 4487 patients for thyroid cancer. Out-patient thyroid bed ablation therapy with 1,110 MBq of 131I accounted for 36.6% of cancer patients. The number of admission rooms increased from 135 to 157 in 5 years. The number of 223Ra targeted therapies for castration-resistant metastatic prostate cancer was 1194 patients. CONCLUSIONS: Single-photon examinations showed a continuous tendency toward a decline in the survey. In contrast, the number of hybrid SPECT/CT scanner examinations has increased. PET/CT study and radionuclide targeted therapy have steadily increased.

Usefulness of 18F-Fluorodeoxyglucose Positron Emission Tomography for Follow-Up of 13-cis-Retinoic Acid Treatment for Residual Neuroblastoma After Myeloablative Chemotherapy.

13-cis-retinoic acid (13-cis-RA) treatment is used as a second-line treatment for residual or recurrent neuroblastoma. However, determining the duration of 13-cis-RA treatment for residual and recurrent neuroblastoma can be a problem because it is difficult to evaluate the effectiveness of the treatment.We performed 13-cis-RA treatment to remove residual active neuroblastoma cells in an 8-year-old boy with stage 4 neuroblastoma that developed from a left sympathetic ganglion and had been treated with chemotherapy, surgery, autologous peripheral blood stem-cell transplantation, and radiotherapy. F-fluorodeoxyglucose positron emission tomography (F-FDG-PET) and iodine-123 metaiodobenzylguanidine (I-MIBG) scintigraphy obtained immediately before 13-cis-RA treatment both showed positive findings in the area of the primary lesion. At 18 months after 13-cis-RA treatment, there was accumulation on I-MIBG scintigraphy but no uptake on F-FDG-PET, and 13-cis-RA treatment was suspended. The patient has been in complete remission for 3 years. In comparing the effectiveness of the 2 imaging modalities for monitoring the response to 13-cis-RA treatment, we considered that F-FDG-PET was superior to I-MIBG scintigraphy because F-FDG-PET images were not affected by the cell differentiation induced by 13-cis-RA treatment in our case. Thus, F-FDG-PET was useful for determining the treatment response and outcomes.We have reported a case of residual neuroblastoma treated with differentiation-inducing 13-cis-RA therapy. Different results were produced with F-FDG-PET and I-MIBG scintigraphy. The cessation of 13-cis-RA treatment was based on F-FDG-PET findings and there has been no relapse for 3 years.

Japanese consensus guidelines for pediatric nuclear medicine. Part 1: Pediatric radiopharmaceutical administered doses (JSNM pediatric dosage card). Part 2: Technical considerations for pediatric nuclear medicine imaging procedures.

The Japanese Society of Nuclear Medicine has recently published the consensus guidelines for pediatric nuclear medicine. This article is the English version of the guidelines. Part 1 proposes the dose optimization in pediatric nuclear medicine studies. Part 2 comprehensively discusses imaging techniques for the appropriate conduct of pediatric nuclear medicine procedures, considering the characteristics of imaging in children.

[Survey questionnaire of pediatric nuclear medicine examinations in 14 Japanese institutes].

Under the auspices of the Japanese Society of Pediatric Nuclear Medicine, an annual aggregate from a 5-year period, 2007 to 2011, of a survey questionnaire of pediatric nuclear medicine examinations performed at 14 institutes in the Kanto region was conducted. The subjects were pediatric patients 15 years old or younger. The survey questions included the determination method for administered dose of radiopharmaceuticals, the items examined and number of examinations. Of 14 institutes, 11 determined administered doses using the formula: adult dose X (age +1) / (age+7), while the remaining 3 used the adult dose as the maximum dose and used a conversion formula based on age and physical condition. In 2011, in a total of 3,884 pediatric patients, renoscintigraphy accounted for 41.5%, brain 14.4%, pulmonary scintigraphy 12.9%, oncology 9.0%, hepatobiliary scintigraphy 6.3%, gastrointestinal scintigraphy 4.8%, musculoskeletal scintigraphy 4.3%, cardiology 2.5%, and other 4.9% of all nuclear medicine examinations. Pediatric nuclear medicine examinations in general hospitals accounted for only 3.4% of all examinations. A similar trend was observed in previous years. Since pediatric patients have a longer reproductive term and higher sensitivity to radiation exposure, pediatric nuclear medicine requires a strict selection of appropriate studies and administered dose. These results show the current practice and would warrant further consideration.

Hypergalactosemia in early infancy: diagnostic strategy with an emphasis on imaging.

BACKGROUND: Portosystemic shunt is one of the main causes of persistent hypergalactosemia without enzyme deficiency, but the diagnostic imaging strategy has not yet been established. The purpose of the present study was to establish a diagnostic imaging strategy. METHODS: A retrospective investigation of the clinical and imaging findings of 10 children with persistent hypergalactosemia without enzyme deficiency detected by screening was undertaken. RESULTS: Abnormal ultrasonography (US) findings were detected in all eight patients with liver disorders. In three patients with citrin deficiency, the combination of fatty liver on US and laboratory evidence of cholestasis led to the diagnosis. In three patients with portosystemic shunt, US on sedation clearly depicted the shunt vessels. The extent was more easily understood on contrast computed tomography (CT). Per-rectal portal scintigraphy with N-isopropyl-p-I-123 iodoamphetamine and lung perfusion scintigraphy with (99m)Tc macroaggregated albumin were useful for evaluation of portal shunt index and assessment of pulmonary arteriovenous shunt. One patient underwent transarterial coil embolization. In two patients with hepatic tumor, the lesions and its vascularity were clearly demonstrated on US and dynamic CT. In one patient, small shunt index on per-rectal portal scintigraphy suggested no need for treatment. The other patient was treated with a combination of steroid, radiation, and interventional radiology. The etiology remained unknown in two children. CONCLUSIONS: In the assessment of hypergalactosemia, US is the modality of choice. CT is a useful tool for more detailed evaluation of the abnormalities found on US. Per-rectal portal scintigraphy and pulmonary perfusion scintigraphy play an important role in the evaluation of portosystemic shunt. Interventional radiology is sometimes effective.

Acute infantile encephalopathy predominantly affecting the frontal lobes.

To establish a novel subtype of acute infantile encephalopathy, the clinical and radiologic features of nine infants with acute encephalopathy involving the bilateral frontal lobes were examined. These patients had convulsive status epilepticus with hyperpyrexia followed by a prolonged impairment of consciousness for 2-20 days. After the recovery of consciousness, all the patients manifested regression of verbal function and lack of spontaneity. Some of them also exhibited stereotypic movements, instability of mood, or catalepsy. Transient postictal edema in both frontal lobes was suggested by diffusion-weighted magnetic resonance imaging. Attenuated cerebral perfusion in the frontal lobes was demonstrated by single-photon emission computed tomography at the tenth day after onset or subsequently. Serial studies disclosed atrophic changes in the frontal lobes. All patients manifested regression or retardation of motor and verbal functions. The recovery of intellectual deficit was slower and less prominent than that of motor dysfunction. These unique features suggest that the frontal lobes are the focus of this novel subtype of acute encephalopathy, which we propose to call acute infantile encephalopathy predominantly affecting the frontal lobes.