Association between PET-CT accumulation in the hypothalamic/pituitary regions and neuron-specific enolase/primary tumor in limited-stage small cell lung cancer: a case-controlled retrospective study.

BACKGROUND: Research on the relationship between neuron-specific enolase (NSE) levels and normal organs, particularly the central nervous system, in small cell lung cancer is limited. Therefore, this study aimed to investigate the relationship between positron emission tomography-computed tomography (PET-CT) accumulation at hypothalamic/pituitary regions, tumor activity, and NSE level in limited-stage small cell lung cancer. We retrospectively analyzed patients who were diagnosed with limited-stage small cell lung cancer at Tokyo Medical University Hospital between July 1, 2019, and May 31, 2023, and were treated with chemoradiotherapy or radiotherapy. Leukocytes, erythrocytes, hemoglobin, platelets, total protein, albumin, NSE, and carcinoembryonic antigen were measured in blood samples obtained before treatment initiation. The maximum standardized uptake value (SUVmax), volume, and total lesion glycolysis (TLG) of each hypothalamic /pituitary region, primary tumor, and lymph node metastases were extracted from PET-CT images. The total tumor volume (primary tumor volume plus lymph node metastases volume) and total TLG (primary tumor TLG plus lymph node metastases TLG) were calculated. RESULTS: This study included 19 patients (mean age, 70.1 ± 8.8 years; 13 men and 6 women); the pathology in all patients was small cell lung cancer. Patients were classified into two groups according to the NSE reference value (16.3 ng/mL): six patients having NSE level below the reference value and 13 having NSE level above the reference value. The SUVmax in the hypothalamic/pituitary region was 2.95 in the NSE < 16.3 ng/mL group and 4.10 in the NSE > 16.3 ng/mL group, with a statistically significant difference (p = 0.03). The total tumor volume was 17.8 mL in the NSE < 16.3 ng/mL group and 98.9 mL in the NSE > 16.3 ng/mL group, with a statistically significant difference (p < 0.01). A correlation coefficient of r = 0.458 (p = 0.0486) was observed between SUVmax in the hypothalamus/pituitary and NSE level. A correlation coefficient of r = 0.647 (p < 0.01) was also observed between total tumor volume and NSE level. Finally, a correlation coefficient of r = 0.53 (p = 0.01) was observed between hypothalamic/pituitary TLG and primary tumor TLG. CONCLUSIONS: The findings demonstrated a correlation between hypothalamic/pituitary activity and tumor activity, suggesting the prognostic significance of NSE.

PET/CT findings and dose distribution during radiotherapy in T1N0M0-T2N0M0 glottic cancer.

OBJECTIVE: To investigate the positron emission tomography/computed tomography (PET/CT) findings of T1/T2N0M0 glottic cancer (hereafter referred to as T1/T2) and dose distribution in radiotherapy. SUBJECTS AND METHODS: We retrospectively collected data from patients diagnosed with T1/T2N0M0 glottic cancer who received radiotherapy. The extent of fluorine-18-fluorodeoxyglucose (18F-FDG) accumulation in primary tumors, maximum standardized uptake value (SUVmax), total lesion glycolysis (TLG), tumor volume of primary tumors on PET/CT were compared. Furthermore, the tumor identified on PET/CT was incorporated into the radiotherapy plans. A dummy plan (radiation field 6x6cm, prescription point facing the vertebral body, maximum dose ≤107%, T1/T2 66Gy/33 fractions) was developed for three-dimensional conformal radiotherapy, and the dose distribution of primary tumors was calculated. RESULTS: Twenty-nine patients (27 men and two women) were included; their mean age was 67.2±15.0 years. Increased 18F-FDG accumulation in primary tumors was observed on PET/CT in 22/29 (78.5%; T1: 14/21 [67%], T2: 8/8 [100%]) patients. The median SUVmax, TLG, and primary tumor volume were significantly different between T1 and T2 (SUVmax, T1: 4.56 vs. T2: 8.43, P=0.035; TLG, T1: 1.01 vs. T2: 3.71 SUVxmL, P<0.01; primary tumor volume, T1: 0.38mL vs. T2: 0.80mL, P=0.01). At a TLG cut-off value of 3.470, the area under the curve was 0.875, sensitivity was 0.875, and specificity was 0.929 for T1-T2 differentiation. In 20 patients with 18F-FDG accumulation, the minimum radiation dose was significantly different between T1 and T2 (66Gy vs. 64Gy, P<0.01) at the same 66Gy prescription. The minimum radiation dose and primary tumor volume show the correlation value (r=-0.516, P=0.02). CONCLUSION: In glottic cancer, T1 and T2 can be differentiated by the extent of 18F-FDG accumulation in primary tumors on PET/CT. The minimum radiation dose rate decreases as volume increases.

Nuclear medicine practice in Japan: a report of the ninth nationwide survey in 2022.

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. The subcommittee sent questionnaires, including the number and category of examinations as well as the kind of the radiopharmaceuticals during the 30 days of June 2022 to all nuclear medicine institutes in Japan. The total numbers of them for the year 2022 were estimated depends on the 1-month data. A total of 1095 institutes responded to the survey, including 364 positron emission tomography (PET) centers. The recovery rate was 90.6%. The number of gamma cameras installed was 1299 in total, with 2.5% decrease in 5 years. Dual-head cameras and hybrid SPECT/CT scanners accounted for 83.8% and 35.5%, respectively. The number of single-photon tracer studies in 2022 was 1.11 million which means increase in 2.7% in 5 years. Bone scintigraphy was a leading examination (31.0%), followed by myocardial scintigraphy (27.1%) and cerebral perfusion study (23.8%) in order. The percentage of SPECT studies showed an increase from 63.5% in previous survey to 66.8% in this survey. PET centers have also increased from 389 to 412, as compared with the previous one. One hundred and twenty-two PET centers have installed one or two in-house cyclotrons. Increasing trends of the PET studies were observed from 1992 to 2017, the trend changed and PET studies showed 1.5% decrease in 5 years. 18F-FDG accounted for 98.6% (610,497 examinations). PET examinations using 11C-methionine, 13N-NH3 and 11C-PIB have decreased, with 1624, 2146 and 525 examinations, respectively in 2022. The total number of nuclear medicine examination was eventually increased by 1.0%. Therapies for pheochromocytoma or paraganglioma (PPGL) with 131I-MIBG and for neuroendocrine tumor with 177Lu-DOTA-TATE were newly started, however, a total number of targeted radionuclide therapy was decreased by 17.7% because 131I-radioiodine and 223Ra targeted therapies were decreased and supply of some radioisotopes was discontinued. 131I-radioiodine targeted therapy showed a decrease in 5 years (- 15.9%), including 4099 patients for thyroid cancer. The number of out-patient thyroid bed ablation therapy with 1110 MBq of 131I was also decreased to 1015 per year. The number of admission rooms specialized for radionuclide targeted therapy increased from 157 to 160. The number of 223Ra targeted therapies for castration-resistant metastatic prostate cancer (mCRPC) was 1041 patients. This survey was performed during COVID-19 pandemic, however, total number of nuclear medicine examinations was almost same as previous survey (+ 1.0%). Radionuclide therapies with 131I-MIBG and 177Lu-DOTA-TATE were newly started, and new radionuclide therapy will be available in future, therefore, the development of radionuclide therapy will be continued. We are convinced that this survey report is useful in understanding the current status of the nuclear medicine practice in Japan, and in devising the new strategy to strengthen a role of nuclear medicine.

Comparison of bone SUV obtained from different SPECT/CT systems.

OBJECTIVE: In bone scintigraphy, it is difficult to compare quantitative values, such as standardized uptake value (SUV), obtained from 2 different single-photon emission computed tomography combined with computed tomography (SPECT/CT) devices owing to differences of imaging acquisition and analysis methods. Therefore, the purpose of this study was to compare the SUV obtained from different SPECT/CT devices using the ratio to normal bone, and to analyze the correlation between them. SUBJECTS AND METHODS: A total of 27 prostate cancer patients who underwent bone scintigraphy either using Symbia T16 or Symbia Intevo (Siemens Medical Solutions, Erlangen, Germany) were retrospectively analyzed. In each patient, spherical voxels of interest were placed on the following 5 reference points: humeral head (humerus), femoral neck (femur), lower part of the ilium (ilium), first lumbar vertebra (L1), fifth lumbar vertebra (L5), and the maximum SUV (SUVmax) and average SUV (SUVave) of these regions were measured. RESULTS: The mean and variance of SUVave (humerus) was the smallest on both SPECT/CT. To compare the SUV obtained from the 2 devices, the SUVave ratio and SUVmax ratio of each region were calculated as the SUVave and SUVmax of each region divided by the SUVave of the humeral head in each patient. Median values of the SUVmax ratio and SUVave ratio of each region showed similar tendencies in both devices, with correlation coefficients between 0.93 and 1.19. CONCLUSION: Our results demonstrated that by expressing the quantitative value of SUVave of each region as a ratio to the SUVave of the humeral head, accumulation in the targeted bone can be compared even when the imaging acquisition and analysis methodsare different.

Mathematical evaluation of post-radiotherapy salivary gland function using salivary gland scintigraphy.

OBJECTIVE: Xerostomia is the most common treatment-related toxicity after radiotherapy (RT) for head and neck carcinoma, reducing the quality of life of patients due to a decrease in salivary gland function. METHODS: Salivary gland scintigraphy was performed to quantitatively evaluate the salivary gland functions in patients undergoing RT. It was done chronologically for 62 salivary glands of 31 patients before RT and retested 12 months later. RESULTS: The salivary gland functions of most patients deteriorated post-RT and recovered when the radiation dose to the salivary gland was not high. The mean dose to the salivary gland was found to be the most reliable factor in deteriorating salivary gland function, and the tolerance dose was determined to be 46 Gy. The recovery rate of salivary gland function after 1 year of RT was 72% in the RT alone group (n = 10), 56% in the conformal radiotherapy group (n = 15), and 44% in the bioradiotherapy group (n = 6). CONCLUSION: Scintigraphy revealed that the salivary glands recovered from post-RT hypofunction when decreased doses were administered. The determined tolerance dose of 46 Gy may guide the approach to minimizing associated xerostomia in RT. ADVANCES IN KNOWLEDGE: In this study, the average tolerated dose to the salivary glands was 46 Gy.

Giant esophageal hemangioma diagnosed by 99mTc-HSA-D scintigraphy following equivocal CT, MRI, and endoscopy.

Mediastinal cavernous hemangioma is a rare lesion requiring diagnosis without invasive procedure due to the risk of hemorrhage, which can be massive and even fatal. Here we describe the successful diagnosis of such a lesion using technetium-99m diethylenetriamine penta-acetic acid human serum albumin (99mTc-HSA-D) scintigraphy. A 36-year-old female with a 3-week back pain underwent endoscopic ultrasonography, contrast-enhanced CT, and MRI dynamic study which together revealed a submucosal tumor of the esophagus; likely to be either hemangioma or lymphangioma. Because of poor or no enhancement, it was impossible to distinguish the nature of the lesion. However, using delayed blood-pool imaging of 99mTc-HSA-D (at 40 minutes postinjection), and the characteristic accumulation, the tumor was clearly identifiable as an esophageal hemangioma. This case shows 99mTc-HSA-D scintigraphy to be an effective noninvasive imaging method to capture the characteristic hemodynamics of hemangioma.

Full report on a survey of adverse reactions to radiopharmaceuticals from 1975 to 2017 in Japan.

OBJECTIVE: This pharmacovigilance-based survey was aimed at determining the prevalence of, and association between, radiopharmaceuticals and adverse reactions to radiopharmaceuticals from 1975 to 2017 in Japan. METHODS: The Subcommittee for Safety Issues of Radiopharmaceuticals of the Japan Radioisotope Association's Medical Science and Pharmaceutical Committee mailed a form for reporting adverse reactions to radiopharmaceuticals to all institutes performing nuclear medicine examinations in Japan. This investigation included adverse reactions to diagnostic radiopharmaceuticals labeled with both single-photon- and positron-emitting radionuclides and therapeutic sodium iodide labeled with 131I. Each institute returned the reporting form to the subcommittee each time an adverse reaction occurred. RESULTS: Replies were obtained from 75% of the institutions. In total, 1099 adverse reactions were reported from 46,645,580 radiopharmaceutical administrations, giving a prevalence of 2.4 adverse reactions per 100,000 administrations (95% confidence interval 2.2-2.5). Adverse reactions were most frequently observed for 131I-iodomethylnorcholesterol (230.1/105 administrations), followed by 131I-HSA (76.3/105 administrations), 131I-sodium iodohippurate (31.2/105 administrations), and 99mTc-DTPA (12.0/105 administrations). Comparison of adverse reactions between before and after 1997 revealed that prevalence dropped from 3.7/105 administrations (95% confidence interval 3.5-4.1) to 1.5/105 administrations (95% confidence interval 1.4-1.6). During the study period, vasovagal reactions accounted for 50.3% of adverse reactions, fever for 7.5%, allergic reactions for 25.7%, and other for 16.5%; 3.7% of all adverse reactions were considered severe but none were lethal. A definite, probable, possible, less likely, and uncertain causal relationship with radiopharmaceuticals was observed in 13.1%, 33.7%, 39.9%, 6.2%, and 7.1% of adverse reactions, respectively. CONCLUSIONS: These results suggest that nuclear medicine staff must be aware of the possibility of adverse reactions from radiopharmaceuticals, despite their rarity.

Adrenocortical Scintigraphy With SPECT/CT for the Diagnosis of Hepatic Adrenal Rest.

Hepatic adrenal rest include ectopic adrenal tissue in the liver and adrenohepatic fusion. Long-lasting hyperstimulation of that tissue induces hyperplasia sometimes simulating true tumors. True autonomic tumors originating from ectopic adrenal tissue with or without hyperfunction are rare. Hepatic adrenal rest sometimes has similar imaging findings to lipid-rich hepatocellular carcinoma or angiomyolipoma, containing obvious lipid component. But in our cases, tumors showed hypervascular patterns similar to hepatocellular adenoma or carcinoma. Therefore, adrenocortical scintigraphy with SPECT/CT should be taken into consideration to diagnose tumoral lesions in the posterior segment of the right hepatic lobe with or without an obvious lipid component.

Efficacy of denosumab for restoring normal bone mineral density in women receiving adjuvant aromatase inhibitors for early breast cancer.

BACKGROUND: Osteoporosis is a major side effect of aromatase inhibitors (AIs), which are greatly effective in the treatment of breast cancer. However, there are no satisfactory measures against osteoporosis. In this multicenter, randomized, comparative study, we evaluate the efficacy of denosumab for preventing loss of bone mineral density (BMD) induced by adjuvant therapy with AI s in breast cancer patients with normal BMD. PATIENTS AND METHODS: The bone loss-suppressing effect of denosumab will be comparatively evaluated in postmenopausal patients scheduled to receive letrozole or anastrozole as a postoperative endocrine therapy for stage I-IIIA hormone-sensitive breast cancer and a control group. Patients will be administered letrozole 2.5 mg or anastrozole 1 mg once a day, and the treatment will be continued for 5 years unless recurrence, secondary cancer, or unacceptable toxicity develops. Patients in the denosumab group will receive a subcutaneous injection of 60 mg of denosumab every 6 months. The primary endpoint is the rate of change in the lumbar spine (L1-L4) BMD, as determined by dual-energy X-ray absorptiometry (DXA), 12 months after the start of the injection. The secondary endpoints were ETHICS AND DISSEMINATION:: The protocol was approved by the institutional review boards of Kyoto Prefectural University of Medicine and all the participating faculties. Written informed consent was obtained from all patients before registration, in accordance with the Declaration of Helsinki. Results of the study will be disseminated via publications in peer-reviewed journals. TRIAL REGISTRATION: Clinical Trials.gov Identifier: NCT03324932, Japan Registry of Clinical Trial (jRCT): CRB5180001.

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.

Effect of denosumab on low bone mineral density in postmenopausal Japanese women receiving adjuvant aromatase inhibitors for non-metastatic breast cancer: 24-month results.

BACKGROUND: Aromatase inhibitors (AI) have been established as the gold-standard therapy for postmenopausal patients. Worldwide, adjuvant denosumab at a dose of 60 mg twice per year reduces the risk of clinical fractures in postmenopausal patients with breast cancer who received AI. However, the efficacy of denosumab in the treatment of AI-associated bone loss had not been prospectively evaluated in Japan. Previously, we reported the 12-month effect of denosumab in Japanese patients for the first time; the primary endpoint was the change in the percentage of bone mineral density (BMD) of the lumbar spine from baseline to 12 months. METHODS: This secondary follow-up study prospectively evaluated the change in the percentage of BMD of the lumbar spine from baseline to 24 months. Postmenopausal women with early-stage, histologically confirmed, hormone receptor-positive, invasive breast cancer who were receiving or scheduled to receive AI were included. Denosumab was administered subcutaneously on day 1 of the study and then 6, 12, 18, and 24 months. The lumbar spine and bilateral femoral neck BMD was measured at baseline and 6, 12, 18, and 24 months. RESULTS: At 18 and 24 months, the lumbar spine BMD increased by 5.9 and 7.0%, respectively. The femoral neck BMD also increased. Grade ≥ 2 hypocalcemia, osteonecrosis of the jaw, and atypical femoral fractures did not occur. CONCLUSIONS: Our prospective study showed that semiannual treatment with denosumab was associated with continuously increased BMD in Japanese women receiving adjuvant AI therapy for up to 24 months, regardless of prior AI treatment.

Japanese Expert Panel Meeting on the Management of Prostate Cancer with Bone Metastases.

INTRODUCTION: The incidence of prostate cancer in Japan continues to increase, necessitating the continued development of effective therapies and strategies. Recent advances in treatments have improved the prognosis of metastatic disease and highlighted the importance of treating bone metastases to reduce the incidence of skeletal complications and improve patients' quality of life. With the increasing number of treatment options that have become available, including bone-targeted therapy with the alpha emitter radium-223 dichloride (Ra-223), Japanese clinicians are faced with making difficult decisions on the choice of optimal treatment strategy. In such situations, guidance based on expert opinions can be beneficial. METHODS: A panel meeting of 27 Japanese experts in the management of prostate cancer was held to share opinions and to establish consensus recommendations on key clinical questions. Panelists were asked to vote on more than 40 questions pertinent to prostate cancer, and the answers helped guide a comprehensive discussion. RESULTS: The panel reached a consensus on key topics related to the optimal treatment strategy for Ra-223 therapy, namely, that patients with symptomatic, metastatic castration-resistant prostate cancer (CRPC) would benefit most from the use of this agent and that this treatment therapy should be provided before chemotherapy. Other topics that achieved consensus included: monitoring for osteoporosis and providing treatment if necessary during androgen deprivation therapy; performing magnetic resonance imaging in the presence of discrepancies in bone scintigram and computed tomography scans; monitoring alkaline phosphatase during CRPC treatment; using osteoclast-targeting in patients with CRPC with bone metastases; and using osteoclast-targeted agents combined with Ra-223. CONCLUSION: These consensus recommendations and the updated information which became available subsequent to the panel meeting included here provide useful information for clinicians to aid in designing optimal treatment strategies for their patients. FUNDING: Bayer Yakuhin Ltd.

Is scintigraphy necessary to detect migration of 125I seeds after brachytherapy for early prostate cancer?

BACKGROUND: We investigated whether scintigraphy was superior to radiography for detecting migrated seeds after brachytherapy for prostate cancer. METHODS: We studied 57 patients with early prostate cancer who were treated with free (125)I transperineal brachytherapy. Scintigraphy was used to detect seed migration on postoperative day (POD) 1, radiography was used on POD 2, and both tests were used on POD 30. RESULTS: The total number of implanted seeds in this study was 3,753 in 57 patients. Overall, there were 19 seed migrations in 12 patients. On POD 1, there were 4 seed migrations in 4 patients that were detected by scintigraphy. On POD 2, there were 10 seed migrations in 9 patients that were detected by radiography. On POD 30, 17 seed migrations were detected in 10 patients by radiography and 18 seeds migrations were detected by scintigraphy. However, 1 seed migration which was located outside of the detectable range of radiography was detected only by scintigraphy. CONCLUSIONS: Both scintigraphy and radiography have similar abilities to detect migrated seeds 1 month after (125)I brachytherapy for prostate cancer. While both tests have advantages and disadvantages, it is reasonable to only use radiography if scintigraphy is not available.

Radiation exposure during sentinel lymph node biopsy for breast cancer: effect on pregnant female physicians.

BACKGROUND: The radionuclide (RN) method employed for sentinel lymph node biopsy is generally safe for adult medical care workers. However, the number of pregnant medical care workers who attend surgery has recently been increasing, along with the increasing number of female surgeons. In particular, female surgeons are concerned about the position of a surgeon's lower abdominal region being close to the RN injection site. We measured the exposure dose of the lower abdominal region in medical care workers and investigated the possible exposure effect on fetuses. METHODS: A dose of (99m)Tc-phytic acid (37 MBq) was subcutaneously injected into the areola of the nipple of patients. Scintigraphy and surgery were performed after 1 and 4 h, respectively. At the time of the local injection, a personal dosimeter measured the exposure dose in the surgeon, first and second assistants, anesthesiologist, and scrub nurse. RESULTS: The median exposure doses were 3, 1, 1, 0, and 0 µSv in the surgeon, first and second assistants, anesthesiologist, and scrub nurse, respectively. Protective clothing reduced the mean exposure dose by 66 %. CONCLUSIONS: In surgeons, the exposure dose from daily life activities (1 mSv/year) corresponds to the dose received after performing 333 surgeries (using 3 µSv as the median). However, the maximum value measured was 24 µSv; at this value, the total exposure dose exceeds 1 mSV in the 42nd surgery. Medical care workers can further reduce their exposure dose by paying attention to the surgical procedure and to their posture and position.

Nuclear medicine practice in Japan: a report of the seventh nationwide survey in 2012.

OBJECTIVE: The Subcommittee on the Survey of Nuclear Medical 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 2012, to all the nuclear medicine institutes. The total numbers for the year 2012 were then estimated. RESULTS: A total of 1,167 institutes responded to the survey, including the 14 in vitro assay institutes and 266 PET centers. The recovery rate was 92 %. The number of gamma cameras installed was 1,425 in total, with 9 % decrease in 5 years. Dual-head cameras and hybrid SPECT/CT scanners accounted for 84 and 10.5 %, respectively. The number of single-photon tracer studies in 2012 was 1.15 million which means decrease in 19 % in 5 years and 29 % in 10 years. All but cerebral perfusion study and sentinel lymphoscintigraphy have decreased. Bone scintigraphy was a leading examination (38.7 %), followed by cardiac studies (29.4 %) and cerebral perfusion study (18.5 %) in order. SPECT studies showed an increase from 42.3 to 47.2 %. PET centers have also increased from 212 to 295, as compared to the last survey. The 135 PET centers have installed one or two in-house cyclotrons. PET studies showed 25.5 % increase in 5 years, with oncology accounting for 96.3 %. (18)F-FDG accounted for 98.2 % (505,990 examinations). PET examinations using (11)C-methionine have been increasing, with 3,352 examinations in 2012. The number of new PET studies using (11)C-PIB PET was 695. (131)I-radioiodine targeted therapies showed an increase, including 3,644 patients (53.6 %) for thyroid cancer and 4,889 patients (17.9 %) for hyperthyroidism. Out-patient thyroid bed ablation therapy with 30 mCi of (131)I accounted for 21.0 % of cancer patients. The number of admission rooms decreased from 158 to 135 in 5 years. In vitro radioassays have been declining continuously since 1992, with the number of studies of 9.0 million in 2012. 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 in the oncology field and radionuclide targeted therapy have steadily increased.

Enhanced diagnostic accuracy for quantitative bone scan using an artificial neural network system: a Japanese multi-center database project.

BACKGROUND: Artificial neural network (ANN)-based bone scan index (BSI), a marker of the amount of bone metastasis, has been shown to enhance diagnostic accuracy and reproducibility but is potentially affected by training databases. The aims of this study were to revise the software using a large number of Japanese databases and to validate its diagnostic accuracy compared with the original Swedish training database. METHODS: The BSI was calculated with EXINIbone (EB; EXINI Diagnostics) using the Swedish training database (n = 789). The software using Japanese training databases from a single institution (BONENAVI version 1, BN1, n = 904) and the revised version from nine institutions (version 2, BN2, n = 1,532) were compared. The diagnostic accuracy was validated with another 503 multi-center bone scans including patients with prostate (n = 207), breast (n = 166), and other cancer types. The ANN value (probability of abnormality) and BSI were calculated. Receiver operating characteristic (ROC) and net reclassification improvement (NRI) analyses were performed. RESULTS: The ROC analysis based on the ANN value showed significant improvement from EB to BN1 and BN2. In men (n = 296), the area under the curve (AUC) was 0.877 for EB, 0.912 for BN1 (p = not significant (ns) vs. EB) and 0.934 for BN2 (p = 0.007 vs. EB). In women (n = 207), the AUC was 0.831 for EB, 0.910 for BN1 (p = 0.016 vs. EB), and 0.932 for BN2 (p < 0.0001 vs. EB). The optimum sensitivity and specificity based on BN2 was 90% and 84% for men and 93% and 85% for women. In patients with prostate cancer, the AUC was equally high with EB, BN1, and BN2 (0.939, 0.949, and 0.957, p = ns). In patients with breast cancer, the AUC was improved from EB (0.847) to BN1 (0.910, p = ns) and BN2 (0.924, p = 0.039). The NRI using ANN between EB and BN1 was 17.7% (p = 0.0042), and that between EB and BN2 was 29.6% (p < 0.0001). With respect to BSI, the NRI analysis showed downward reclassification with total NRI of 31.9% ( p < 0.0001). CONCLUSION: In the software for calculating BSI, the multi-institutional database significantly improved identification of bone metastasis compared with the original database, indicating the importance of a sufficient number of training databases including various types of cancers.

(89)Sr imaging with bremsstrahlung in patients with metastatic breast cancer.

PURPOSE: In this study, we investigated the clinical and laboratory factors that may enhance (89)Sr uptake to strengthen its tumoricidal effect. METHODS: We enrolled 21 patients with multiple bone metastases (n = 23) from breast cancer and classified them into 2 groups according to their zoledronic acid (ZOL) treatment history. (89)Sr imaging with bremsstrahlung was performed 2 to 6 weeks after administration and (89)Sr index was measured using combined imaging with bone scintigraphy. We compared the Sr index with the levels of alkaline phosphatase, bone-specific alkaline phosphatase, serum cross-linked N-telopeptides, carboxy-terminal telopeptide of type 1 collagen, C-reactive protein, calcium, and hemoglobin on administration and evaluated the differences among the groups. RESULTS: The (89)Sr index ranged from 0.01 to 2.0 and was significantly correlated with C-reactive protein and alkaline phosphatase and moderately correlated with carboxy-terminal telopeptide of type 1 collagen, serum cross-linked N-telopeptides, and bone-specific alkaline phosphatase. The (89)Sr index was not significantly correlated with calcium or hemoglobin. The group with less than 1 year of ZOL treatment demonstrated a mean (SD) (89)Sr index of 1.11 (0.59), and the group with 1 or more years of ZOL treatment showed a mean (89)Sr index of 0.36 (0.26). The Wilcoxon signed-rank test demonstrated a significant difference between the 2 groups (P < 0.001). CONCLUSIONS: (89)Sr accumulation seemed to be associated with bone turnover, in particular bone resorption, and vascularization due to inflammation or tumor growth. Long-term ZOL treatment may reduce bone resorption and vascularization. To enhance the tumoricidal effect and palliation of bone pain by (89)Sr, combined therapy must be established.

Concurrent use of Sr-89 chloride with zoledronic acid is safe and effective for breast cancer patients with painful bone metastases.

Our aim in this study was to examine the safety and efficacy of the concurrent use of the radiopharmaceutical strontium-89 (Sr-89) chloride with zoledronic acid in standard anticancer therapy for breast cancer patients with painful multifocal bone metastases. The study comprised 16 breast cancer patients with painful multifocal bone metastases detected by bone scintigraphy, computed tomography or magnetic resonance imaging. All patients were treated with Sr-89 and zoledronic acid concurrently between March 2007 and February 2011 as part of a standard therapeutic regimen comprising chemotherapy, endocrine therapy, molecular targeting therapy and targeted radiotherapy. Sr-89 was administered intravenously at 2 MBq/kg to a maximum of 141 MBq per person. Safety was evaluated according to myelotoxicity as measured by the Common Terminology Criteria for Adverse Events (v3.0). To assess treatment efficacy, we monitored changes in analgesic drug dosages. Furthermore, bremsstrahlung imaging after the administration of Sr-89 was utilized to examine the relationship between the accumulation of Sr-89 in metastatic sites and treatment efficacy. Based on the results, a total of 14 out of 16 patients (88%) reported bone pain relief, indicating a high efficacy of Sr-89 combined with zoledronic acid. In responsive cases, a strong uptake of Sr-89 was observed on bremsstrahlung imaging at the same sites indicated by (99m)Tc bone scintigraphy. Moreover, severe myelosuppression (> grade 3) was not observed, and adverse events were tolerable. In conclusion, the use of Sr-89 with zoledronic acid in breast cancer patients with painful bone metastases was safe and effective when administered concurrently with other standard therapies. In the future, the treatment with Sr-89 at the early stage should be considered, and a large-scale clinical study should be conducted.