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.