Utility of single-photon emission tomography/computed tomography for sentinel lymph node localization in breast cancer patients.

OBJECTIVES: Sentinel lymph node (SLN) mapping is currently a routine technique in breast cancer management and preoperative scintigraphic imaging plays a crucial role in the process of SLN detection. The guidelines recommend performing planar acquisition and optional single-photon emission tomography/computed tomography (SPECT/CT) imaging. The aim of this study was to verify whether routine performing of SPECT/CT in addition to planar imaging increases the sensitivity of SLN detection in patients with early-stage breast cancer. The secondary aims were to compare radionuclide SLN imaging with intraoperative SLN detection and identify clinical and histopathological factors affecting the SLN detection rate. MATERIALS AND METHODS: A total of 153 early-stage breast cancer patients underwent lymph node scintigraphy in the years 2007-2013. Breast cancer patients with staging T1-2N0M0 were included. Planar and SPECT/CT lymphoscintigraphy were performed on the day before the surgery. The data on presence or absence of SLN, their number and localization were recorded for both methods and compared with each other as well as with intraoperative blue dye staining and histopathological findings. RESULTS: SPECT/CT identified SLN in 119/153 and planar scintigraphy in 114/153 patients. Identification rates were 77.7 and 74.5%, respectively. Intraoperative lymph node assessment identified SLN in 76/126 cases with an identification rate of 60.3%. Identification rates for second echelon lymph node were 34.6% for hybrid imaging and 21.2% for planar scintigraphy. Statistical analysis did not yield a significant difference in diagnostic accuracy between these methods; however, the Wilcoxon signed-rank test showed that SPECT/CT significantly increases SLN identification rate compared with planar scintigraphy and intraoperative detection. Histopathological examination of excised SLN showed that 22 nodes were metastatic. SPECT/CT visualized all of these, whereas planar imaging and intraoperative lymph node detection procedure visualized 19 and 18, respectively. No clinical and histopathological factors affecting SLN detection rate were identified. CONCLUSION: Hybrid SPECT/CT lymphatic mapping yields a high SLN detection rate in patients with early-stage breast cancer and provides lymph node localization details. It identifies more SLN than planar imaging and intraoperative SLN detection. However, its limited superiority over the remaining two methods does not support its routine use for SLN localization. We suggest using SPECT/CT for SLN detection in case of equivocal planar imaging results.

Incidentally recognised thyroid focal uptake of 99mTc-sestamibi during stress myocardial perfusion scintigraphy.

INTRODUCTION: 99mTc-sestamibi, a radiopharmaceutical widely used in the assessment of myocardial perfusion, can be used as an indicator of thyroid disease due to its oncophilic character. The aim of this study was to establish the usefulness of performing additional examinations of radiotracer uptake in the thyroid gland during standard stress scintigraphy with sestamibi in order to identify thyroid diseases. MATERIAL AND METHODS: After a retrospective evaluation of 330 consecutive myocardial perfusion scintigraphies performed in our hospital during one year, 41 patients with a focal accumulation of 99mTc-sestamibi in the thyroid were enrolled in the study. The patients underwent clinical examinations, including thyroid ultrasonography and TSH, fT4, fT3, aTPO, TRAB, calcitonin, and CEA levels. Based on the thyroid ultrasounds, 21 patients were referred for fine-needle aspiration biopsy of the thyroid. RESULTS: An abnormal accumulation of radiotracer in the thyroid was found in 41(12.4%) of 330 patients who underwent stress cardiac scintigraphy. Thirteen (31.7%) of those patients had multinodular euthyroid goitres, 12 (29.2%) had a single thyroid nodule (including two autonomous nodules), 11 (26.8%) had autoimmune thyroid disease, and one (2.4%) had papillary thyroid carcinoma. In 12 (29.2%) with thyroid tracer uptake there was no thyroid pathology. CONCLUSIONS: Additional evaluation of radiotracer uptake in the thyroid during standard myocardial perfusion scintigraphy is a valuable tool in the detection of thyroid diseases. The additional or parallel evaluation of radiotracer uptake in the thyroid should be considered during every myocardial scintigraphy.

Long bone metastases as predictors of survival in patients with metastatic renal cancer.

BACKGROUND: The aim of this study was to assess the prevalence of long bone metastases in renal cancer patients and to evaluate their utility as predictors of survival in this group. MATERIAL AND METHODS: This retrospective study included 20 patients with metastatic renal cancer and bone metastases. The patients were referred for regular bone scintigraphy in order to assess disease spread in the skeleton. The patients were divided into two groups: those with 1) metastases in the skeleton (including long bones) and those with 2) metastases in the axial skeleton only. RESULTS: Bone scintigraphy imaging was performed regularly up to 81 months from the first positive bone scan. During that time 11 deaths (8 among patients with long bone lesions) were recorded. Kaplan-Meyer curves showed that patients with long bone metastases tend to have lower survival probability in comparison to the ones with metastases in other bones. CONCLUSIONS: Bone metastases localization seems to influence survival in patients with renal cancer. Long bone-involving spread of the disease is associated with worse survival probability than the spread to the other bones.

Brain metastases in patient with prostate cancer found in 18F-choline PET/CT.

Brain metastases are a rare complication of prostate cancer. They are usually diagnosed in an end-stage disease when the tumor has already spread to the other organs and tissues. We present a case of a male with castration-resistant prostate cancer with bone metastases visualized in ¹8F-fluorocholine PET/CT scan.

Detection of splenic tissue by 99mTc-labelled Sn-colloid SPECT/CT scintigraphy.

This paper presents a case of an 80-year-old man with idiopathic thrombocytopenic purpura after splenectomy performed many years ago, which normalized platelet count, presented with severe thrombocytopenia with no response to treatment. A SPECT/CT study was performed using 99mTc-labelled Sn-colloid. The histology confirmed the presence of splenic tissue in those foci. Spleen examination (SPECT/CT) using 99mTc-labelled Sn-colloid is able to detect splenic tissue and in our opinion is a simpler and less time-consuming procedure than using 99mTc DRBC.