The added value of SPECT/CT in the evaluation of equivocal skeletal lesions in patients with known malignant disease

[摘要] ENGLISH SUMMARY: Introduction: Bone scintigraphy is used extensively in evaluating metastatic disease.There are currently no clear recommendations for the use of SPECT/CT in metastaticbone disease. Existing procedural guidelines from the Society of Nuclear Medicine(SNM) for SPECT/CT do not provide specific indications for use of SPECT/CT in bonescintigraphy, and there are currently no other guidelines for the use of SPECT/CT inbone scintigraphy that the author is aware of. The aim of this study was to investigatethe additional value of SPECT/CT, and to identify the clinical indications for whichSPECT/CT is most useful in patients with suspected bone metastases.Subjects and Methods: Forty-two patients with equivocal lesions on planarscintigraphy were prospectively recruited and planar imaging, SPECT, and SPECT/CTdone on all patients. On reading of SPECT and then SPECT/CT, patients and individuallesions were classified as malignant, benign or equivocal. Radiological studies andavailable clinical information were also used during reading of scans. Review of clinicalinformation, radiological studies and/or follow-up bone scans were used as goldstandard. The results of the SPECT and SPECT/CT were compared in terms ofproportion of equivocal findings and accuracy. Results: Forty-two patients with 189 skeletal lesions were examined. There was adiverse variety of primary tumours, although the majority had breast (n=22) or prostatecancer (n=8). Overall, SPECT/CT resulted in a significant reduction in the proportion ofequivocal findings on both a patient-wise (p=0.0015) and lesion-wise basis (p<0.0001).The overall accuracy of SPECT/CT was significantly higher than that of SPECT on botha patient-wise (p=0.0026) and lesion-wise basis (p<0.0001). Generally SPECT/CTdecreased the proportion of equivocal findings and increased the accuracy independentof the presence of bone pain, type of primary tumour, or skeletal region involved.SPECT/CT did not significantly improve the diagnostic confidence of readers inequivocal lumbar lesions although accuracy was significantly improved in this region.Conclusion: SPECT/CT performs significantly better than SPECT alone for theinterpretation of equivocal planar lesions. There is no evidence that the benefit ofSPECT/CT is dependent on the type of primary tumour or the presence of bone pain.Where resources are limited, SPECT/CT is indicated only in those patients in whomcorrect classification of the lesions in question is expected to alter the patient'smanagement. SPECT/CT images should be interpreted with the aid of a diagnosticradiologist or nuclear medicine physicians should acquire sufficient experience inComputed Tomographic image interpretation in order to optimise diagnostic benefit fromSPECT/CT.

[发布机构] Stellenbosch University