Image fusion analysis of 99mTc-HYNIC-Tyr3-octreotide SPECT and diagnostic CT using an immobilisation device with external markers in patients with endocrine tumours

In view of the commercial success of integrated PET/CT scanners, there is an increasing interest in comparable SPECT/CT systems. SPECT in combination with CT enables a direct correlation of anatomic information and functional information, resulting in better localization and definition of scintigraphic findings. Besides anatomic referencing, the added value of CT coregistration is based on the attenuation correction capabilities of CT. The number of clinical studies is limited, but pilot studies have indicated a higher specificity and a significant reduction in indeterminate findings. The superiority of SPECT/CT over planar imaging or SPECT has been demonstrated in bone scintigraphy, somatostatin receptor scintigraphy, parathyroid scintigraphy, and adrenal gland scintigraphy. Also, rates of detection of sentinel nodes by biopsy can be increased with SPECT/CT. This review highlights recent technical developments in integrated SPECT/CT systems and summarizes the current literature on potential clinical uses and future directions for SPECT/CT in cardiac, neurologic, and oncologic applications.

show abstract

“…(55). The addition of clinically relevant information for 40% of patients by SPECT/CT compared with SPECT was described by Gabriel et al (56).…”

Section: Spect/ct In Neuroendocrine Tumorsmentioning

confidence: 99%

Spect/Ct

Buck¹,

Nekolla²,

Ziegler³

et al. 2008

J Nucl Med

284

149

View full text Add to dashboard Cite

show abstract

“…Small pulmonary lesions can escape detection by nuclear medicine techniques because of their limited spatial resolution as compared with anatomically oriented methods (20). Therefore, contrast-enhanced multislice CT can be considered an essential imaging method for the evaluation of NET (21).…”

Section: Use Of Lesion Diameter To Predict Therapy Response With 68 Gmentioning

confidence: 99%

⁶⁸Ga-DOTA-Tyr³-Octreotide PET for Assessing Response to Somatostatin-Receptor–Mediated Radionuclide Therapy

Gabriel¹,

Oberauer²,

Dobrozemsky³

et al. 2009

J Nucl Med

Self Cite

179

129

View full text Add to dashboard Cite

68 Ga-labeled 1,4,7,10-tetraazacyclododecane-N,N9,N99,N999-tetraacetic acid-D-Phe 1 -Tyr 3 -octreotide (DOTA-TOC) PET has proven its usefulness in the diagnosis of patients with neuroendocrine tumors. Radionuclide therapy ( 90 Y-DOTA-TOC or 177 Lu-DOTA-octreotate) is a choice of treatment that also requires an accurate diagnostic modality for early evaluation of treatment response. Our study compared 68 Ga-DOTA-TOC PET with CT or MRI using the Response Evaluation Criteria in Solid Tumors. Furthermore, standardized uptake values (SUVs) were calculated and compared with treatment outcome. Methods: Forty-six patients (29 men, 17 women; age range, 34-84 y) with advanced neuroendocrine tumors were investigated before and after 2-7 cycles of radionuclide therapy. Long-acting somatostatin analogs were not applied for at least 6 wk preceding the follow-up. Data were acquired with a dedicated PET scanner. Emission image sets were acquired at 90-100 min after injection. 68 Ga-DOTA-TOC PET images were visually interpreted by 2 experienced nuclear medicine physicians. For comparison, multislice helical CT scans and 1.5-T MRI scans were obtained. Attenuation-corrected PET images were used to determine SUVs. Repeated CT evaluation and other imaging modalities, for example, 18 F-FDG, were used as the reference standard. Results: According to the reference standard, 68 Ga-DOTA-TOC PET and CT showed a concordant result in 32 patients (70%). In the remaining 14 patients (30%), discrepancies were observed, with a final outcome of progressive disease in 9 patients and remission in 5 patients. 68 Ga-DOTA-TOC PET was correct in 10 patients (21.7%), including 5 patients with progressive disease. In these patients, metastatic spread was detected with the follow-up whole-body PET but was missed when concomitant CT was used. On the other hand, CT confirmed small pulmonary metastases not detected on 68 Ga-DOTA-TOC in 1 patient and progressive liver disease not detected on 68 Ga-DOTA-TOC in 3 patients. Quantitative SUV analysis of individual tumor lesions showed a large range of variability. Conclusion: 68 Ga-DOTA-TOC PET shows no advantage over conventional anatomic imaging for assessing response to therapy when all CT information obtained during follow-up is compared. Only the development of new metastases during therapy was detected earlier in some cases when whole-body PET was used. SUV analysis of individual lesions is of no additional value in predicting individual responses to therapy.

show abstract

“…For every image acquisition (PET, SPECT, and CT), the patient was repositioned into the vacuum mattress (11). The image fusion procedure was used for anatomic delineation of abnormal findings in SPECT and PET.…”

Section: Ct and Image Fusion Proceduresmentioning

confidence: 99%

“…However, these methods sometimes lack specificity, as conclusions regarding malignant involvement of organ structures are based only on size criteria and the contrast enhancement pattern (11).…”

mentioning

confidence: 99%

68Ga-DOTA-Tyr3-Octreotide PET in Neuroendocrine Tumors: Comparison with Somatostatin Receptor Scintigraphy and CT

Gabriel¹,

Decristoforo²,

Kendler³

et al. 2007

Journal of Nuclear Medicine

919

557

View full text Add to dashboard Cite

The aim of this study was to evaluate the diagnostic value of a new somatostatin analog, 68 Ga-labeled 1,4,7,10-tetraazacyclododecane-N,N9,N$,N$9-tetraacetic acid-D-Phe 1 -Tyr 3 -octreotide ( 68 Ga-DOTA-TOC), for PET in patients with known or suspected neuroendocrine tumors. PET was compared with conventional scintigraphy and dedicated CT. Methods: Eighty-four patients (48 men, 36 women; age range, 28-79 y; mean age 6 SD, 58.2 6 12.2 y) were prospectively studied. For analysis, patients were divided into 3 groups: detection of unknown primary tumor in the presence of clinical or biochemical suspicion of neuroendocrine malignancy (n 5 13 patients), initial tumor staging (n 5 36 patients), and follow-up after therapy (n 5 35 patients). Each patient received 100-150 MBq 68 Ga-DOTA-TOC. Imaging results of PET were compared with 99m Tc-labeled hydrazinonicotinyl-Tyr 3 -octreotide ( 99m Tc-HYNIC-TOC) and 111 In-DOTA-TOC. CT was also performed on every patient using a multidetector scanner. Each imaging modality was interpreted separately by observers who were unaware of imaging findings before comparison with PET. The gold standard for defining true-positive (TP), true-negative (TN), false-positive (FP), and false-negative (FN) results was based on all available histologic, imaging, and follow-up findings. Results: PET was TP in 69 patients, TN in 12 patients, FP in 1 patient, and FN in 2 patients, indicating a sensitivity of 97%, a specificity of 92%, and an accuracy of 96%. The FP finding was caused by enhanced tracer accumulation in the pancreatic head, and the FN results were obtained in patients with a tumor of the gastrointestinal tract displaying liver metastases. 68 Ga-DOTA-TOC showed higher diagnostic efficacy compared with SPECT (TP in 37 patients, TN in 12 patients, FP in 1 patient, and FN in 34 patients) and diagnostic CT (TP in 41 patients, TN in 12 patients, FP in 5 patients, and FN in 26 patients). This difference was of statistical significance (P , 0.001). However, the combined use of PET and CT showed the highest overall accuracy. Conclusion: 68 Ga-DOTA-TOC PET shows a significantly higher detection rate compared with conventional somatostatin receptor scintigraphy and diagnostic CT with clinical impact in a considerable number of patients.

show abstract

Image fusion analysis of 99mTc-HYNIC-Tyr3-octreotide SPECT and diagnostic CT using an immobilisation device with external markers in patients with endocrine tumours

Cited by 52 publications

References 15 publications

Spect/Ct

Spect/Ct

⁶⁸Ga-DOTA-Tyr³-Octreotide PET for Assessing Response to Somatostatin-Receptor–Mediated Radionuclide Therapy

68Ga-DOTA-Tyr3-Octreotide PET in Neuroendocrine Tumors: Comparison with Somatostatin Receptor Scintigraphy and CT

Contact Info

Product

Resources

About

Image fusion analysis of 99mTc-HYNIC-Tyr3-octreotide SPECT and diagnostic CT using an immobilisation device with external markers in patients with endocrine tumours

Cited by 52 publications

References 15 publications

Spect/Ct

Spect/Ct

68Ga-DOTA-Tyr3-Octreotide PET for Assessing Response to Somatostatin-Receptor–Mediated Radionuclide Therapy

68Ga-DOTA-Tyr3-Octreotide PET in Neuroendocrine Tumors: Comparison with Somatostatin Receptor Scintigraphy and CT

Contact Info

Product

Resources

About

⁶⁸Ga-DOTA-Tyr³-Octreotide PET for Assessing Response to Somatostatin-Receptor–Mediated Radionuclide Therapy