@misc{oai:repo.qst.go.jp:00071319,
 author = {Yoshikawa, Kyosan and Ohashi, Seiya and Toubaru, Sachiko and Hasebe, Mitsuhiko and Tamura, Katsumi and Shiraishi, Takahiro and Tanimoto, Katsuyuki and Yamada, Shigeru and Kandatsu, Susumu and Zhang, Ming-Rong and Saga, Tsuneo and Kamada, Tadashi and 吉川 京燦 and 大橋 靖也 and 桃原 幸子 and 長谷部 充彦 and 田村 克巳 and 白石 貴博 and 谷本 克之 and 山田 滋 and 神立 進 and 張 明栄 and 佐賀 恒夫 and 鎌田 正},
 month = {Oct},
 note = {Adoption of metabolic imaging with F-18-FDG in staging and follow up of cancers needs tumor metabolism parameters like standardized uptake value (SUV). SUVmax,the value of the single voxel with the maximum intensity, avoids inter-observer differences, but a major drawback of SUVmax is its susceptibility to noise in the data. SUVpeak defined as the largest possible mean value of a 1 cm3 spherical VOI positioned within a tumor removes inter-observer variation and reduces the susceptibility to noise. In this study we compared SUVpeak against SUVmax of glucose metabolic activity of pancreas cancer, and assessed how much the SUVpeak was likely to differ from SUVmax using Bland-Altman plot.
Method:
A total of 53 patients (35 males, 18 females; mean age, 67+-8 y) with pancreas cancer underwent F-18-FDG PET/CT scan in pre-and post-carbon ion radiotherapy. All patients were followed more than 1 year after treatment. The following parameters were measured: maximum standardized uptake value (SUVmax) and peak SUVs (SUVpeak6, SUVpeak10, SUVpeak15). SUVpeak6, SUVpeak10 and SUVpeak15 are measured using spherical VOI with radius 6 mm, 10 mm and 15 mm, respectively, where the volume of spherical VOI of SUVpeak6 is almost 1 cm3. The overall survival was estimated using the Kaplan-Meier method with SUVs as prognostic variables. Bland-Altman plots were used to evaluate difference between SUVmax and SUVpeak in pre-and post-treatment scan.
Results: 
Cutoff values for each SUV were defined by ROC analysis, and the probability of survival was significantly lower with increasing FDG uptake measured by all the kinds of SUVs in both pre-and post-treatment.
Significant correlations were observed between SUVmax and SUVpeak6, SUVpeak10 or SUVpeak15 in both pre-and post-treatment. However, proportional bias was observed between SUVmax and SUVpeak6, SUVpeak10 or SUVpeak15 in both pre-and post-treatment as revealed by the Bland-Altman plot analysis. The Bland-Altman analysis illustrated that the 95% limits of agreement is smaller between SUVmax and SUVpeak6 (range: pre 0.25, post 0.16) than between SUVmax and SUVpeak10 (range: pre 0.40, post 0.23), and is also smaller between SUVmax and SUVpeak10 than between SUVmax and SUVpeak15 (rang: 0.62, post 0.35). 
Conclusions: 
SUVmax and SUVpeak were statistically significant prognostic variables for overall survival estimated using the Kaplan-Meire method. SUVmax as FDG-PET uptake parameter was correlated closely to SUVpeak, but there was proportional bias between SUVmax and SUVpeak. The smaller the sphere's radius of SUVpeak the smaller the 95% limits of agreement is., EANM'13 - Annual Congress of the European Association of Nuclear Medicine},
 title = {Comparison between SUVmax and SUVpeak of FDG uptake in pancreas cancer:Bland-Altman plot analysis},
 year = {2013}
}