Sung Kim

Scintigraphic patterns of the reflex sympathetic dystrophy syndrome of the lower extremities

Thirty-two patients with clinical signs and symptoms of the reflex sympathetic dystrophy syndrome (RSDS) of the lower extremities underwent Tc-99m MDP bone scintigraphy. Twenty-three patients had abnormal scan findings consistent with RSDS, while the scans of the remaining nine patients were normal. Of the 23 patients with abnormal scans, 19 demonstrated increased periarticular activity on early and delayed images, while 4 patients demonstrated decreased activity in the affected limb.

Radioembolization for Treatment of Salvage Patients with Colorectal Cancer Liver Metastases: A Systematic Review

Currently, there is no consensus on the use of 90Y radioembolization for salvage patients with colorectal cancer liver metastases. The purpose of this study was to provide a comprehensive overview of the available data on tumor response and survival after 90Y radioembolization for this group of patients. Methods: A systematic literature search was conducted in PubMed (Medline), Excerpta Medica (EMBASE), and the Cochrane Library (September 2012) with synonyms for “radioembolization” and “colorectal cancer liver metastases.” Results were described separately for patient cohorts treated with 90Y radioembolization as monotherapy and with 90Y radioembolization in combination with chemotherapy. Results: The search yielded 13 relevant articles for systematic review on 90Y radioembolization as monotherapy and 13 relevant articles on 90Y radioembolization combined with chemotherapy. Disease control rates (i.e., complete response, partial response, and stable disease) ranged from 29% to 90% for 90Y radioembolization as monotherapy and from 59% to 100% for 90Y radioembolization combined with chemotherapy. Heterogeneity in the data prohibited pooling of response rates. Survival proportions at 12 mo ranged from 37% to 59% for 90Y radioembolization as monotherapy and from 43% to 74% for 90Y radioembolization combined with chemotherapy. Conclusion: In the studies included in this systematic review, approximately 50% of salvage patients with colorectal cancer liver metastases survive more than 12 mo after treatment with 90Y radioembolization, either as monotherapy or in combination with chemotherapy. Heterogeneity between studies has unfortunately prohibited pooling of data. Future research will discern the precise role of 90Y radioembolization in general clinical practice in comparison with chemotherapy.

Planar and SPECT Tc-99m red blood cell imaging in hepatic cavernous hemangiomas and other hepatic lesions.

The utility of Tc-99m BBC imaging in the diagnosis of hepatic cavernous hemangiomas has been established. Of the 25 patients with various focal hepatic lesions evaluated, 16 were diagnosed as having hemangiomas: eight proven by surgery, two proven by angiography, and six proven by maintaining a stable clinical course ranging from 6 to 12 months with normal follow-up liver function tests. Although fourteen of these were detected by planar imaging, two were detected by SPECT only. Two patients with large hemangiomas had false-negative scans, whereas the remaining seven patients had other liver lesions.

VPAC1 Receptors for Imaging Breast Cancer: A Feasibility Study

VPAC1 encodes G-protein–coupled receptors expressed on all breast cancer (BC) cells at the onset of the disease, but not on benign lesions. Our extensive preclinical studies have shown that 64Cu-TP3805 has a high affinity for VPAC1, is stable in vivo, and has the ability to distinguish spontaneously grown malignant BC masses from benign lesions. Our long-term goal is to develop 64Cu-TP3805 as an agent to perform in vivo histology, to distinguish malignant lesions from benign masses noninvasively and thereby avoid patient morbidity and the excess economic costs of benign biopsies. Methods: 18F-FDG obtained commercially served as a control. 64Cu-TP3805 was prepared using a sterile kit containing 20 μg of TP3805. Radiochemical purity and sterility were examined. Nineteen consenting women with histologically proven BC were given 370 MBq of 18F-FDG. One hour later, 6 of these patients were imaged with PET/CT and 13 with positron emission mammography (PEM). Two to 7 d later, 6 PET/CT patients received 111 MBq (±10%) (n = 2), 127 MBq (±10%) (n = 2), or 148 MBq (±10%) (n = 2) of 64Cu-TP3805 and were imaged 2 and 4 h later. Thirteen PEM patients received 148 MBq (±10%) of 64Cu-TP3805 and were imaged 15 min, 1 h, 2 h, and 4 h later. Standardized uptake value (SUV) was calculated for PET/CT patients, and PUV/BGV (PEM uptake value/background value) was calculated for PEM patients. Tumor volume was also calculated. Results: The radiochemical purity of 64Cu-TP3805 was 97% ± 2%, and specific activity was 44.4 GBq (1.2 Ci)/μmol. In 19 patients, a total of 24 lesions were imaged (15 invasive ductal carcinoma, 1 high-grade mammary carcinoma, 3 lobular carcinoma, 1 invasive papilloma, and 4 sentinel lymph nodes). All lesions were unequivocally detected by 64Cu-TP3805 and by 18F-FDG. The average tumor volume as determined by PET/CT with 64Cu-TP3805 was 90.6% ± 16.1% of that with 18F-FDG PET/CT, and the average SUV was 92% ± 26.4% of that with 18F-FDG. For PEM, the tumor volume with 64Cu-TP3805 was 113% ± 37% of that with 18F-FDG and the PUV/BGV ratio was 97.7% ± 24.5% of that with 18F-FDG. Conclusion: 64Cu-TP3805 is worthy of further investigation in patients requiring biopsy of suggestive imaging findings, to further evaluate its ability to distinguish malignant lesions from benign masses noninvasively.

VPAC1 Targeted 64Cu-TP3805 Positron Emission Tomography Imaging of Prostate Cancer: Preliminary Evaluation in Man

OBJECTIVE To evaluate (64)Cu-TP3805 as a novel biomolecule, to positron emission tomography (PET) image prostate cancer (PC), at the onset of which VPAC1, the superfamily of G protein-coupled receptors, is expressed in high density on PC cells, but not on normal cells. MATERIALS AND METHODS Twenty-five patients undergoing radical prostatectomy were PET/X-ray computerized tomography imaged preoperatively with (64)Cu-TP3805. Standardized maximum uptake (SUVmax) values were determined and malignant lesions (standardized uptake value > 1.0) counted, and compared with histologic findings. Whole-mount pathology slides from 6 VPAC1 PET imaged patients, 3 benign prostatic hyperplasia patients, 1 malignant and 1 benign lymph node underwent digital autoradiography (DAR) after (64)Cu-TP3805 incubation and were compared to hematoxylin- and eosin-stained slides. RESULTS In 25 patients who underwent PET imaging, 212 prostate gland lesions had SUVmax > 1.0 vs 127 lesions identified by histology of biopsy tissues. The status of the additional 85 PET identified prostate lesions remains to be determined. In 68 histologic slides from 6 PET imaged patients, DAR identified 105 of 107 PC foci, 19 of 19 high-grade prostatic intraepithelial neoplasias, and ejaculatory ducts and verumontanum involved with cancer. Additionally, DAR found 9 PC lesions not previously identified histologically. The positive and negative lymph nodes were correctly identified, and in 3 of 3 benign prostatic hyperplasia patients and 5 of 5 cysts, DAR was negative. CONCLUSION This feasibility study demonstrated that (64)Cu-TP3805 delineates PC in vivo and ex vivo, provided normal images for benign masses, and is worthy of further studies.

Hepatic angiosarcoma mimicking cavernous hemangioma

Hepatic cavernous hemangioma (HCH) is the most common benign liver tumor, often discovered as an incidental finding on ultrasound or CT scan of the abdomen. Liver imaging with Tc-99m labeled red blood cells (RBCs) is often used to diagnose this lesion. The authors report a patient whose RBC scan results were suggestive of HCH. However, the final diagnosis was angiosarcoma of the liver. Therefore, angiosarcoma results in a potential false-positive for the detection of HCH in RBC liver imaging. The similar scan appearance is most likely a result of similar histology because both are very vascular lesions

Lymphedema of the lower extremities: Evaluation by microcolloidal imaging

Contrast lymphangiography has been the traditional radiographic method for imaging the lymphatic system of the lower extremities. Because of the difficulty in performing the procedure and its potential side effects, radionuclide lymphanglography is a safe and reliable alternative. Technetium-99m labeled to antimony trisulfide colloid was used in nine patients presenting with lymphedema of the lower extremities. The procedure was relatively simple to perform, and no adverse effects were noted.

Dynamic hepatobiliary scan appearance of hepatocellular carcinoma

A case of hepatocellular carcinoma demonstrating increased Tc-99m DISIDA concentration on both dynamic and static scans of the liver is presented.

Currently Available Radiopharmaceuticals for Imaging Infection and the Holy Grail

Infection is ubiquitous. However, its management is challenging for both the patients and the health-care providers. Scintigraphic imaging of infection dates back nearly half a century. The advances in our understanding of the pathophysiology of disease at cellular and molecular levels have paved the way to the development of a large number of radiopharmaceuticals for scintigraphic imaging of infection. These include radiolabeling of blood elements such as serum proteins, white blood cells (WBCs), and cytokines, to name a few. Infectious foci have also been imaged using a radiolabeled sugar molecule by taking advantage of increased metabolic activity in the infectious lesions. Literature over the years has well documented that none of the radiopharmaceuticals and associated procedures that facilitate imaging infection are flawless and acceptable without a compromise. As a result, only a few compounds such as 99mTc-hexamethylpropyleneamineoxime, 18F-FDG, the oldest but still considered as a gold standard 111In-oxine, and, yes, even 67Ga-citrate in some countries, have remained in routine clinical practice. Nonetheless, the interest of scientists and physicians to improve the approaches to imaging and to the management of infection is noteworthy. These approaches have paved the way for the development of numerous, innovative radiopharmaceuticals to label autologous WBCs ex vivo or even those that could be injected directly to image infection or inflammation without direct involvement of WBCs. In this review, we briefly describe these agents with their pros and cons and place them together for future reference.

A glance at imaging bladder cancer

PurposeEarly and accurate diagnosis of bladder cancer (BCa) will contribute extensively to the management of the disease. The purpose of this review was to briefly describe the conventional imaging methods and other novel imaging modalities used for early detection of BCa and outline their pros and cons.MethodsLiterature search was performed on Pubmed, PMC, and Google scholar for the period of January 2014 to February 2018 and using such words as “bladder cancer, bladder tumor, bladder cancer detection, diagnosis and imaging”.ResultsA total of 81 published papers were retrieved and are included in the review. For patients with hematuria and suspected of BCa, cystoscopy, and CT are most commonly recommended. Ultrasonography, MRI, PET/CT using 18F-FDG, or 11C-choline and recently PET/MRI using 18F-FDG also play a prominent role in detection of BCa.ConclusionFor initial diagnosis of BCa, cystoscopy is generally performed. However, cystoscopy cannot accurately detect carcinoma in situ and cannot distinguish benign masses from malignant lesions. CT is used in two modes, CT and computed tomographic urography, both for diagnosis and for staging of BCa. However, they cannot differentiate T1 and T2 BCa. MRI is performed to diagnose invasive BCa and can differentiate muscle invasive bladder carcinoma from non-muscle invasive bladder carcinoma. However, CT and MRI have low sensitivity for nodal staging. For nodal staging, PET/CT is preferred. PET/MRI provides a better differentiation of normal and pathologic structures as compared with PET/CT. Nonetheless none of the approaches can address all issues related for the management of BCa. Novel imaging methods that target specific biomarkers, image BCa early and accurately, and stage the disease are warranted.