OBJECTIVE: To compare and correlate technetium-99m methylene diphosphonate uptake between benign and metastatic bone lesions using semiquantitative analysis of maximum standard uptake value (SUVmax) and mean Hounsfield unit (HU) in single-photon emission computed tomography-computed tomography (SPECT-CT).
BACKGROUND: Qualitative interpretation of metastatic bone lesions in breast cancer on bone scintigraphy is often complicated by coexisting benign lesions.
METHODS: In total, 185 lesions were identified on bone and SPECT-CT scans from 32 patients. Lesions were classified as metastatic (109 sclerotic lesions) and benign (76 lesions) morphologically on low-dose CT. Semiquantitative analysis using SUVmax and mean HU was performed on the lesions and compared. To discriminate benign and metastatic lesions, the correlation between SUVmax and mean HU was determined using the intraclass correlation coefficients.
RESULTS: The SUVmax was higher in metastatic lesions (20.66±14.36) but lower in benign lesions (10.18±12.79) (p<0.001). The mean HU was lower in metastatic lesions (166.62±202.02) but higher in benign lesions (517.65±192.8) (p<0.001). A weak negative correlation was found between the SUVmax and the mean HU for benign lesions, and a weak positive correlation was noted between the SUVmax and the mean HU on malignant lesions with no statistical significance (p=0.394 and 0.312, respectively). The cutoff values obtained were 10.8 for SUVmax (82.6% sensitivity and 84.2% specificity) and 240.86 for the mean HU (98.7% sensitivity and 88.1% specificity) in differentiating benign from malignant bone lesions.
CONCLUSIONS: Semiquantitative assessment using SUVmax and HU can complement qualitative analysis. Metastatic lesions had higher SUVmax but lower mean HU than benign lesions, whereas benign lesions demonstrated higher mean HU but lower SUVmax. A weak correlation was found between the SUVmax and the mean HU on malignant and benign lesions. Cutoff values of 10.8 for the SUVmax and 240.86 for the mean HU may differentiate bone metastases from benign lesions.
■使用单光子发射计算机断层扫描(SPECT-CT)中最大标准摄取值(SUVmax)和平均Hounsfield单位(HU)的半定量分析,比较和关联99m亚甲基二膦酸盐在良性和转移性骨病变之间的摄取。
■在骨闪烁显像上对乳腺癌转移性骨病变的定性解释通常因并存的良性病变而复杂化。
■总共,在32例患者的骨和SPECT-CT扫描中发现185个病灶。在低剂量CT上,病变在形态学上分为转移性(109个硬化性病变)和良性(76个病变)。使用SUVmax和平均HU对病变进行半定量分析并进行比较。区分良性和转移性病变,SUVmax和平均HU之间的相关性使用组内相关系数确定.
■转移性病变的SUVmax较高(20.66±14.36),而良性病变的SUVmax较低(10.18±12.79)(p<0.001)。转移性病变的平均HU较低(166.62±202.02),而良性病变的平均HU较高(517.65±192.8)(p<0.001)。对于良性病变,SUVmax和平均HU之间存在弱负相关,在恶性病变上,SUVmax和平均HU之间呈弱正相关,无统计学意义(分别为p=0.394和0.312)。在区分良性和恶性骨病变方面,SUVmax的临界值为10.8(灵敏度为82.6%,特异性为84.2%),平均HU为240.86(灵敏度为98.7%,特异性为88.1%)。
■使用SUVmax和HU的半定量评估可以补充定性分析。与良性病变相比,转移性病变的SUVmax较高,但平均HU较低,而良性病变显示较高的平均HU,但较低的SUVmax。在恶性和良性病变上,SUVmax与平均HU之间存在弱相关性。SUVmax的截止值为10.8,平均HU的截止值为240.86,可以将骨转移与良性病变区分开。