The work was aimed at studying clinical significance of increased

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F-FDG（fluorodeoxyglucose） uptake in sternum.Forty-six patients with increased

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F-FDG uptake in sternum in PET/CT examination were analyzed retrospectively

grouped according to the disease types.SUVmax（maximal standardized uptake value） values of focus were measured

and CT features and the distribution of increased

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F-FDG uptake were compared.Fifty normal volunteers were used as controls.T-test was used to compare the SUVmax among patients groups

and between the controls and patients groups.Between malignant sternal metastasis group and hematopathy group

Chi square test was carried out to check the distribution of increased

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F-FDG uptake and sternum bone changes

and to see whether the vertebrae or ribs were involved.The final diagnoses of all the patients were confirmed by pathology.The SUVmax value of patients groups was significantly higher than the controls（p

<

0.001）.Malignant sternal metastasis group and hematopathy group was each twenty-three cases

account for 50%（23/46）

there was no significant difference between the SUVmax value of the two groups（p=0.181）.Increased

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F-FDG uptake in sternum of malignant sternal metastasis group mainly showed focal

whereas the hematopathy group showed more diffused（χ

2

=10.52

p=0.001）. With the sternal bone changes or not

there was significant difference between the two groups（χ

2

=7.10

p=0.008）. These both groups often involved vertebrae or ribs（χ

2

=1.10

p=0.295）.Increased

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F-FDG uptake in sternum should be highly alert to malignant tumor metastasis or hematopathy.The distribution of increased

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F-FDG uptake and bone changes in sternum

which had a great reference value to identify the two kinds of diseases

but this could not identify whether the vertebrae or ribs was affected.