Concordance between freehand SPECT and conventional scintigraphy for sentinel lymph node detection in breast cancer

INTRODUCTION

Freehand SPECT can be a useful imaging technique for preoperative planning of sentinel lymph node biopsy (SLNB) as it allows localization of the sentinel node by 3D and real-time tomographic imaging and determines its depth after a few minutes of scanning. The aim of the study was to evaluate the correlation between the number of detected SNs between freehand SPECT images and lymphoscintigraphy (LS).

MATERIALS AND METHODS

100 patients with a diagnosis of invasive breast cancer and no clinical evidence of lymph node involvement prospectively underwent SLNB. The preoperative study included freehand SPECT imaging at 15min after injection and LS imaging at 25 and 60-90min after injection (early and late). The observed agreement was analyzed and a concordance study was performed between the number of SNs detected with freehand SPECT and LS.

RESULTS

The observed agreement in the detection of SNs between freehand SPECT and early LS was 72%; between freehand SPECT and late LS was 85%; and between early and late LS was 87%. In the concordance study, there was moderate concordance between freehand SPECT and early LS (kappa coefficient: 0.42); moderate-high concordance between freehand SPECT and late LS (kappa coefficient: 0.60); and moderate-high concordance between early and late LS (kappa coefficient: 0.70), with no significant differences between them (p-value=0.16).

CONCLUSION

Freehand SPECT showed a moderate-high concordance with conventional imaging studies and could be a valid alternative for the presurgical study of SLNB in breast cancer.

[Diagnostic value of parathyroid localization techniques in surgery for primary hyperparathyroidism]

OBJECTIVES

To determine the accuracy of imaging techniques for localization of nodular lesions of parathyroid glands.

MATERIAL AND METHODS

Seventy one patients were prospectively enrolled and underwent surgical examination for primary hyperparathyroidism. Ultrasonography (US), 201Tl/99mTc parathyroid subtraction scintigraphy and 99mTc MIBI scintigraphy were evaluated.

RESULTS

The sensitivity and specificity for combined 201Tl/99mTc parathyroid subtraction scintigraphy and US for parathyroid adenomas were 72.27% and 89.22% respectively. The combination of 99mTc MIBI scintigraphy and US resulted in improved specificity (93.67%) and positive predictive value (80.39%). The accuracy of the localizing studies was lower for patients with hyperplasia.

CONCLUSIONS

The combination of scintigraphy and US is the best approach for localization of nodules. In most cases, the two techniques are complementary.

[Scintigraphy with labelled leukocytes in acute pancreatitis. Preliminary results]

This study aims to evaluate the contribution of the 99mTc-HMPAO labelled leukocyte in the prognostic assessment of patients with acute pancreatitis. We have compared the usual methods of prognostic evaluation (computed tomography CT and the Ranson clinical score scale) with the scintigraphic findings in 23 consecutive patients with a clinical diagnosis of mild or severe acute pancreatitis. All 6 patients with severe pancreatitis showed an uptake which was mostly mild. 9/17 patients with mild pancreatitis showed uptake, which also frequently had a low intensity. When the severity index of CT was compared with the leukocyte results, the only patient with a high severity index showed a grade 3 uptake. However, in over 50% of the patients with a low severity index, uptake, generally having a low intensity, was found. When the uptake degree was compared with the Ranson score level, we observed a predominance of mild uptake in both patients with mild and severe pancreatitis. Considering these results, we believe that the lack of uptake in the leukocyte study in a patient with acute pancreatitis can be interpreted as a good prognosis sign. The significance of the finding of uptake in the pancreatic area is uncertain and studies should be performed in larger sized samples.