Size Control of 99mTc-tin Colloid Using PVP and Buffer Solution for Sentinel Lymph Node Detection

Colloidal particle size is an important characteristic that allows mapping sentinel nodes in lymphoscintigraphy. This investigation aimed to introduce different ways of making a 99mTc-tin colloid with a size of tens of nanometers. All agents, tin fluoride, sodium fluoride, poloxamer-188, and polyvinylpyrrolidone (PVP), were mixed and labeled with 99mTc. Either phosphate or sodium bicarbonate buffers were used to adjust the pH levels. When the buffers were added, the size of the colloids increased. However, as the PVP continued to increase, the size of the colloids was controlled to within tens of nanometers. In all samples, phosphate buffer added PVP (30 mg) stabilized tin colloid (99mTc-PPTC-30) and sodium bicarbonate solution added PVP (50 mg) stabilized tin colloid (99mTc-BPTC-50) were chosen for in vitro and in vivo studies. 99mTc-BPTC-50 (100 nm) mainly accumulated in the liver. When a rabbit was given a toe injection, the node uptake of 99mTc-PPTC-30 decreased over time, while 99mTc-BPTC-50 increased. Therefore, 99mTc-BPTC-50 could be a good candidate radiopharmaceutical for sentinel node detection. The significance of this study is that nano-sized tin colloid can be made very easily and quickly by PVP.

Camparison of the Efficiency for Tc-99m Tin-colloid and Tc-99m Phytate in Sentinel Node Detection in Breast Cancer Patients / 핵의학분자영상

PURPOSE: Lymphoscintigraphy and sentinel node biopsy has become a standard method for detection of axillary lymph node metastasis in breast cancer patients, but the standard radiopharmaceutical was not prepared. About detection of axillary lymph node metastasis by lymphoscintigraphy and sentinel node biopsy in breast cancer patient, we compared the results of Tc-99m Tin-colloid and Tc-99m Phytate by subareolar injection. MATERIALS AND METHODS: This study included 382 breast cancer patients who were performed operation during 2001-2008. Three hundred forty nine patients was injected 0.8 ml of Tc-99m Tin-colloid (37-185 MBq) by subareolar injection. Thirty three patients was injected 0.8 ml of Tc-99m Phytate (37-185 MBq). Lymphoscintigraphy was performed in supine position and sentinel node localization was performed by hand-held gamma probe in operation. RESULT: Among 349 patients by Tc-99m Tin-colloid, 312 cases (89.4%) localized the sentinel node by lymphoscintigraphy, 304 cases (87.1%) localized by gamma probe. Among 33 patients by Tc-99m Phytate, 32 cases (97.0%) localized by lymphoscintigraphy, 33 cases (100%) localized by gamma probe. Detection rate by lymphoscintigraphy and gamma probe was superior for Tc-99m Phytate compared to that with Tc-99m Tin-colloid, with a statistically significant difference. (p<0.05, p<0.05) CONCLUSION: Tc-99m Phytate is a better choice for localization of sentinel node than Tc-99m Tin-colloid in breast cancer patients.

Comparison of the Results for Sentinel Lymph Node Mapping in the Breast Cancer Patients using 99mTc-Antimony Trisulfide Colloid, 99mTc-Tin Colloid, and 99mTc-Human Serum Albumin / 핵의학분자영상

PURPOSE: In the breast cancer patient, lymphatic mapping and sentinel lymph node biopsy are the most important procedure for axillary lymph node staging. We aimed to compare the three radiocolloids [99mTc-antimony trisulfide colloid (ASC), 99mTc-tin colloid (TC), and 99mTc-human serum albumin (HSA)] for sentinel lymph node mapping. SUBJECTS AND METHODS: Totally, 397 patients with clinically N0 stage were enrolled. 99mTc-ASC was injected in 202 out of 397 patients, 99mTc-TC was injected in 120 patients, and 99mTc-HSA was injected in the remaining 75 patients. The sentinel lymph nodes were localized by lymphoscintigraphy and selected using intraoperative gamma probe. All sentinel lymph nodes were investigated by intraoperative pathologic consultation. The axillary lymph nodes which were harvested by the lymph node dissection were also investigated. RESULTS: The patients of each group showed similar clinical characteristics. There were no significant differences (p>0.05) in the identification rate of sentinel lymph nodes (IR), false negative rate (FNR), and negative predictive value (NPV). The axillary lymphadenectomy revealed axillary lymph node metastases in those three groups (ASC-33.2%, TC-31.7%, HSA-22.7%). The IR, FNR, and NPV were not significantly different among those groups. CONCLUSION: Those three 99mTc-labeled radiocolloids showed equivalent results in sentinel lymph node mapping of breast cancer.

A Static Scintigraphy for Imaging Aspiration Using Semi-Solid Food / 핵의학분자영상

PURPOSE: Aspiration scintigraphy is a procedure of nuclear imaging to evaluate aspiration and of quantifying the amount of aspirate. The ultimate goal of our study is to define the correlation between aspiration and aspiration pneumonia by aspiration scintigraphy, and this is a preliminary report of its trial. MATERIALS AND METHODS: Ten patients with positive findings by videofluoroscopy were selected. The patients ingested semi-solid food containing Tc-99m tin colloid 92.5 MBq (2.5 mCi) and images were acquired immediately after the ingestion and 3 hrs later. A fraction of aspiration to the ingested was calculated using an equation with a decay correction. RESULTS: Five patients were interpreted positive by aspiration scintigraphy. Four patients were positive at initial images and the fractions of aspiration were 0.11%, 0.11%, 0.81%, and 0.11%. The one patient who was shown aspirated at both images had initial 5.82% and delayed 2.26%. CONCLUSION: Aspiration scintigraphy enables us to localize the aspiration at any desired time of the test and to quantify its amount. Follow-up studies are warranted.

Utiliy of Breast Sentinel Lymph Node Biopsy Using the Day-Before or the Same-Day Subareolar Injection of (99m)Tc-Tin Colloid / 한국유방암학회지

PURPOSE: The aims of this study were to examine the feasibility of sentinel lymph node (SLN) biopsy using the day-before-surgery or the same-day subareolar injection of (99m)Tc-Tin colloid, and to evaluate the accuracy of performing intraoperative multiple frozen section diagnosis of the SLN for breast cancer. METHODS: From Jul. 2003 to Feb. 2004, a total of 81 women with clinically node negative breast cancer underwent SLN biopsy and this was followed by axillary lymph node dissection at the Korea Cancer Center Hospital. 2-2.5mCi of (99m)Tc-Tin colloid was injected intradermally in the outer upper edge of the areola on the day before or the same day of surgery, and lymphoscintigraphy was then obtained. The time interval between the injection of tracer and SLN biopsy varied from 1 hour to 20 hours. Intraoperatively, the status of the SLNs was examined by multiple frozen section diagnosis and all the SLNs were subjected to serial sectioning for Hematoxylin-eosin staining and immunohistochemical staining for cytokeratin. After removal of the SLNs, standard level I and II axillary dissection was performed in all patients. RESULTS: In 26 patients (32.1%), the SLNs were positive for tumor cells among these 26 patients. 16 patients (61.5%) results showed that the SLNs were the only metastatic nodes. Two cases of false negative findings were identified. The sensitivity and specificity were 92.9% and 100% respectively. In the second half of this study, no false-negative cases were found in 41 consecutive patients. CONCLUSION: The results of SLN biopsy using the day-before-surgery or same-day subareolar injection of (99m)Tc-Tin colloid were excellent for identification of the SLNs. This technique does not interfere with effective treatment in the operating room because the time interval between the injection and surgery did not affect the results of SLN biopsy. Intraoperative multiple frozen section diagnosis of SLNs was readily available, and this was highly accurate for assessing the status of SLNs

The Usefulness of Measurement of Whole Body Count in Assessing Bone Marrow Metastasis in Cancer Patients with Increased Periarticular Bone Uptake on Follow-up Bone Scan: A Comparison with Bone Marrow Scan / 대한핵의학회잡지

PURPOSE: Increased periarticular uptake could be associated with peripheral bone marrow expansion in cancer patients with axial bone marrow metastasis. We compared bone scan and bone marrow scan to investigate whether the increased whole body count in patients with increased periarticular uptake on bone scan is useful in the diagnosis of axial marrow metastasis, and evaluate the role of additional bone marrow scan in these cases. MATERIALS AND METHODS: Twelve patients with malignant diseases who showed increased periarticular uptake on bone scan were included. Whole body count was measured on bone scan and it is considered to be increased when the count is more than twice of other patients. Bone marrow scan was taken within 3-7 days. RESULTS: Five hematologic malignancy, 3 stomach cancer, 2 breast cancer, 1 prostate cancer and 1 lung cacner were included. All three patients with increased whole body count on bone scan showed axial marrow suppression and peripheral marrow expansion. Eight of 9 patients without increased whole body count showed axial marrow suppression and peripheral marrow expansion. One turned out to be blastic crisis of chronic myelogeneous leukemia, and seven showed normal axial marrow with peripheral marrow expansion in chronic anemia of malignancy. The last one without increased whole body count showed normal bone marrow scan finding. CONCLUSION: Increased whole body count on bone scan could be a clue to axial bone marrow metastasis in cancer patients with increased periarticular uptake, and bone marrow scan is a valuable method for differential diagnosis in these cases.