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Objective Hip pain arising from implant instability is generally caused by repetitive stress injury, which subsequently leads to induction or exacerbation of abnormal metabolism of bone around the implant. single photon emission tomography/computed tomography (SPECT-CT) has advantages in localizing areas of increased tracer uptake that reflects such abnormal bone metabolism. Therefore, we investigated whether the application of SPECT/CT with stress analysis can be an effective practice in evaluating the instability of stem in noncemented hip arthroplasty or not. Method In total 16 patients were collected for unexplained painful hip arthroplasties. When physical examination and blood tests were unremarkable, radiographs were inconclusive and bone scan indicated increased scintigraphic uptake at the proximal part and at the tip of the stem; SPECT/CT was performed. Stem stability was assessed by measuring whether there was consistency between the increased scintigraphic uptake and the direction of the stress around the implant along with the location of the prosthesis. Result Among the 16 symptomatic hips, 9 hips showed the stability of the stem, 3 hips showed the stem instability and 4 hips showed the acetabular loosening with the stem stability. With the application of SPECT/CT with stress analysis, 15 out of 16 (93.7%) cases were found to have the change in the diagnoses, and managements were implemented in 11 out of 16 (68.7%) cases. When comparing before and after SPECT/CT, there was no significant association in clinical diagnosis and management (Pearson chi- square test = 4.61 and 1.33, P = 0.33 and 0.25). Conclusion SPECT/CT combined with stress analysis can be a useful tool in early diagnosis of stem instability and can assist surgeons in subsequent management and decision implementation when other radiographic imagings are inconclusive.

The purpose of this study was to assess the relationship between (99m)Tc-MIBI and (99m)Tc-MDP bone scintigraphy and clinical or pathological variables, including preoperative serum PTH levels and tumor diameter, in patients with newly diagnosed PHPT.Dual-phase (99m)Tc-MIBI planar scintigraphy was performed in 244 patients with PHPT. Of these patients, 155 underwent (99m)Tc-MDP bone scintigraphy to detect bone changes before parathyroidectomy. Factors influencing (99m)Tc-MIBI scintigraphy and (99m)Tc-MDP bone scintigraphy detection rate were assessed using univariate and multivariate logistic regression analysis; optimal cutoff values for predicting positive (99m)Tc-MIBI and (99m)Tc-MDP bone scintigraphy were evaluated using ROC analysis.Among 244 patients, 174 (71.31 %) patients with 181 foci had a positive (99m)Tc-MIBI planar scintigraphy; delayed neck and thorax SPECT/CT could identify and locate the (99m)Tc-MIBI lesions but could not find more lesions than planar scintigraphy. 70 (28.69 %) patients had a negative (99m)Tc-MIBI planar scintigraphy. Tumor diameter, serum PTH level and symptoms were statistically significant predictive factors in predicting positive (9m)Tc-MIBI scintigraphy both univariate and multivariate logistic regression analyses. The optimal thresholds for tumor diameter and serum PTH by ROC analysis were 1.03 cm and 127.60 ng/L, respectively. Among 155 patients with bone scintigraphy, (99m)Tc-MDP bone scintigraphy showed positive finding in 80 (51.61 %) patients and negative finding in 75 patients. Univariate logistic regression analysis showed that patient age, sex, tumor diameter and PTH level (≥150 ng/L) were statistically significant in predicting positive (99m)Tc-MDP bone scintigraphy. Multivariate logistic regression analysis showed both tumor diameter and PTH ≥ 150 ng/L were statistically significant in predicting positive (99m)Tc-MDP bone scintigraphy. The optimal thresholds for tumor diameter and serum PTH by ROC analysis were 1.96 cm and 163.85 ng/L, respectively.The utility of delayed neck and thorax SPECT/CT over dual-phase (99m)Tc-MIBI planar scintigraphy is that it can identify and locate a parathyroid tumor in about more than 70 % of patients in PHPT and provide the assistance for surgical planning. These studies also suggest that (99m)Tc-MIBI scintigraphy and (99m)Tc-MDP bone scintigraphy are closely correlated with tumor diameter and PTH; which may show negative results when tumor diameter is small and serum PTH level is low.

Parathyroid carcinoma is a rare endocrine malignancy that accounts for a small percentage of patients with primary hyperparathyroidism. Here, an unusual patient with parathyroid carcinoma misdiagnosed as a parathyroid adenoma was reported. A solitary L4 vertebral metastasis, which was localized by technetium-99m-labelled methoxyisobutyl isonitrile ((99m)Tc-MIBI) single photon emission computed tomography (SPECT)/computed tomography (CT) fusing images, was successfully treated with percutaneous vertebroplasty (PVP) for the first time.A 53-year-old man with primary hyperparathyroidism and a palpable mass in the right neck was referred. A right unilateral parathyroidectomy was performed. A pathological diagnosis of parathyroid adenoma was made; however, hyperparathyroidism persisted with a serum calcium of 4.51 mmol/L and a PTH of 3235 pg/mL. Early and delayed images of the (99m)Tc-MIBI whole-body scan revealed abnormal (99m)Tc-uptake in the lower abdomen. The delayed (99m)Tc-MIBI SPECT/CT fusion images found that the lower abnormal (99m)Tc-MIBI uptake was located in the area of osteolytic destruction of the L4 vertebra. A bone metastasis from parathyroid carcinoma was diagnosed based on histopathological evaluation and immunohistochemical staining. PVP was performed to treat the osteolytic destruction of the L4 vertebra. The PTH level decreased to normal within 1 week after PVP.(99m)Tc-MIBI SPECT/CT scan may be a useful and suitable method by which to localize functioning distant metastases from the parathyroid cancer when serum PTH and calcium levels remain greatly elevated after parathyroidectomy. PVP may be an effective procedure in eliminating cancer cells, reducing serum PTH levels, preventing bone fractures, and improving the quality of life of patients.

Herpes simplex virus thymidine kinase (HSV-TK) gene/ganciclovir (GCV) system has been widely used as a traditional gene therapy modality, and the sodium/iodide symporter gene (NIS) has been found to be a novel therapeutic gene. Since the therapeutic effects of radioiodine therapy or prodrug chemotherapy on cancers following NIS or HSV-TK gene transfer need to be enhanced, this study was designed to investigate the feasibility of radiochemotherapy for hepatocarcinoma via coexpression of NIS gene and HSV-TK gene. Methods HepG2 cells were stably transfected with NIS, TK and GFP gene via recombinant lentiviral vector and named HepG2/NTG. Gene expression was examined by reverse transcriptase polymerase chain reaction, fluorescence imaging and iodide uptake. The therapeutic effects were assessed by MTT assay and clonogenic assay. Results HepG2/NTG cells concentrated 125 I − up to 76-fold higher than the wild-type cells within 20 min, and the efflux happened with a T 1/2eff of less than 10 min. The iodide uptake in HepG2/NTG cells was specifically inhibited by sodium perchlorate. Dose-dependent toxicity to HepG2/NTG cells by either GCV or 131 I was revealed by clonogenic assay and MTT assay, respectively. The survival rate of HepG2/NTG cells decreased to 49.7%±2.5%, 43.4%±2.8% and 8.6%±1.2% after exposure to 131 I, GCV and combined therapy, respectively. Conclusion We demonstrate that radiochemotherapy of hepatocarcinoma via lentiviral-mediated coexpression of NIS gene and HSV-TK gene leads to stronger killing effect than single treatment, and in vivo studies are needed to verify these findings.

Background The present study investigated several tumor markers in patients receiving multiple radioiodine treatments after thyroidectomy for differentiated thyroid carcinoma (DTC). Methods Serological tests for tumor markers (Tg, CFEA, CA125, CA19-9, CA72-4, and Cyfra 21-1) were performed in 57 patients with pulmonary metastases (subjects) and 76 patients without distant metastases (controls). Results Serum thyroglobulin was much higher in the subjects than in the controls (median, 595.0 versus 5.4 μg/L, P 0.05). CA72-4 was positive in 20.3% with more positive cases in those having received higher doses (cutoff dose 25.9 GBq, 36.8% versus 13.7%, P =0.003). Conclusion These tumor markers are not likely progression-related and are not recommended for the follow up of DTC patients unless other malignancies are indicated. The high sensitivity of CA72-4 may be related to radiation damage to the gastrointestinal mucosa.

131I whole-body scintigraphy (WBS) is a highly sensitive method for the detection of differentiated thyroid tumors and metastases. However, a lack of anatomic landmarks and the physiologic accumulation of the tracer complicate interpretation of the images. This prospective study was designed to evaluate the incremental value of 131I SPECT/CT over planar WBS in the management of patients with differentiated thyroid carcinoma (DTC). Methods: Planar imaging was performed on 66 consecutive DTC patients who were considered to have locally advanced or metastatic disease after total or nearly total thyroidectomy. SPECT/CT was added for patients whose planar findings were inconclusive. The planar images were interpreted by 2 experienced nuclear medicine physicians. Interpretation of the SPECT/CT images was a consensus opinion of one of the nuclear medicine physicians and an experienced radiologist. Fusion images were considered to improve image interpretation when they better localized sites of increased 131I uptake. The final diagnosis was verified by pathologic findings, other imaging modalities, and clinical follow-up. Both site-based and patient-based analyses were performed, and the impact of SPECT/CT results on therapeutic strategy was assessed. Results: A total of 232 foci were observed by 131I WBS, including 33.2% of foci localized in the thyroid bed, 62.1% due to malignant lesions, and 4.7% caused by nonthyroidal physiologic or benign uptake or a contaminant. Overall, 37 SPECT/CT studies were performed on 23 patients, whose planar images showed 81 inconclusive lesions. Precise localization and characterization of 131I-avid foci were achieved through 131I SPECT/CT in 69 (85.2%) and 67 (82.7%) of the 81 foci, respectively. Fusion images were considered to be of benefit in 17 (73.9%) of 23 patients. The therapeutic strategy was changed in 8 (47.1%) of 17 patients. Uncommon metastatic lesions were found in 9 (13.6%) of 66 patients with regard to SPECT/CT fusion images. Conclusion: Fusion of SPECT and CT images was of incremental value over WBS in increasing diagnostic accuracy, reducing pitfalls, and modifying therapeutic strategies in 73.9% of DTC patients. As SPECT/CT techniques emerge, 131I SPECT/CT may demonstrate higher value than WBS in the management of DTC.

Annexin B1, a novel Ca2+-dependent PS-binding protein, has been shown to have a high affinity for PS exposed on the surface of apoptotic cells. To develop and bioevaluate an annexin B1 based PS-targeting radiotracer, annexin B1 was radiolabeled with (99m)Tc using HYNIC as a bifunctional chelator. Binding assays with activated platelets and apoptotic SP2/0 cells were carried out to evaluate the in vitro biological activity of (99m)Tc-HYNIC-annexin B1. Biodistribution of this radioligand was studied in normal mice. Dexamethasone-induced murine thymus apoptosis and fas-mediated murine liver apoptosis models were used to investigate the ability of radiolabeled annexin B1 to detect apoptosis in vivo. The labeling procedure yielded a compound with up to 98% radiochemical purity and good in vitro stability. The in vitro binding assays indicated that (99m)Tc-HYNIC-annexin B1 retain its PS-binding activity. Biodistribution of the compound in mice showed that (99m)Tc-HYNIC-annexin B1 is rapidly cleared from the blood and predominantly accumulates in the kidney. The marked increase in dexamethasone-treated murine thymus uptake and fas-mediated murine liver uptake correlated with histologic evidence of apoptosis. These data suggested that (99m)Tc-HYNIC-annexin B1 retain its in vitro and in vivo biological activities. This radiotracer may therefore be useful as a novel radioligand for the noninvasive detecting of PS externalization associated with apoptosis.

The sodium iodide symporter (NIS) gene could be used as an ideal reporter gene as well as a promising therapeutic gene. 99m Tc-pertechnetate has proven to be more advantageous than 131 I-iodide with respect to image quality, procedure and radiation dose in examination of thyroid uptake and scintigraphy. Herein, we investigated the feasibility of monitoring human sodium iodide symporter (hNIS) gene expression with 99m Tc-pertechnetate in hepatoma cells (MH3924A) following tissue-specific expression. Methods MH3924A cells were stably transfected with the recombinant retroviral vector, in which hNIS cDNA was driven by murine albumin enhancer/promoter (mAlb) and coupled to hygromycin resistance gene using an internal ribosomal entry site. Functional NIS expression in hepatoma cells was confirmed by an 125 I − uptake assay. The dynamic uptake and efflux of 99m Tc-pertechnetate was determined both in vitro and in vivo. Results The 99m Tc-pertechnetate was up to 254-fold higher in stably transfected MH3924A cells than in wild-type cells. However, the in vitro efflux of 99m Tc-pertechnetate out of recombinant cells was rapid with a half-life of less than 2 min. Further, the in vivo studies yielded clear images and quantitative data of mAlbhNIS-infected tumor xenografts using 99m Tc-pertechnetate and γ camera. Conclusion The current study demonstrates enhanced 99m Tc-pertechnetate uptake in hepatoma cells in vitro and in vivo following tissue-specific gene transfer using a recombinant retrovirus with the albumin enhancer/promoter and the hNIS gene. It is feasible to monitor hNIS gene expression noninvasively and quantitatively using conventional γ camera and 99m Tc-pertechnetate.

Sorafenib has shown promise in the treatment of patients with advanced or metastatic thyroid carcinoma. However, its therapeutic effect has not been assessed in patients with brain metastases from follicular thyroid carcinoma (FTC). Here, we report a patient in whom this treatment was employed with a relatively favorable response.A 56-year-old woman had a thyroidectomy 8 years previously for FTC. She subsequently developed lung metastases, for which she received seven courses of radioiodine ((131)I) therapy. She developed right hemiplegia and other symptoms and was found to have a ≈ 5-cm lesion in the left parietal lobe. Radiosurgery with a total dose of 28 Gy (7 Gy/day, for 4 days) to treat her brain metastatic lesion was ineffective, and she was referred to us. We treated her with sorafenib, 200 mg orally, on a twice-daily basis. The effect of this intervention was assessed clinically and radiographically using Response Evaluation Criteria in Solid Tumors (RECIST).Symptoms and signs improved dramatically and continuously after initiation of sorafenib treatment. Partial response (PR) in the brain metastasis and stable disease (SD) in lung metastatic lesions were verified by consecutive imaging findings for more than one year. Despite alopecia, other treatment-related adverse events did not occur.Targeted therapy such as with sorafenib could be an effective alternative therapeutic strategy in the treatment of progressive brain metastasis from differentiated thyroid carcinoma (DTC) when surgery, external beam radiation, and (131)I are not suitable or give poor outcomes. A paradigm of sustained low dose of sorafenib (200 mg,twice a day) may be well-tolerated without compromising maintenance of the therapeutic effect.

Sorafenib has shown promise in the treatment of patients with advanced or metastatic thyroid carcinoma. However, the optimal dose has not been established and data on Chinese population are not available. We conducted a study to assess the responses to sorafenib at a low dose of 200 mg twice daily in patients with progressive radioiodine-refractory pulmonary metastases from papillary thyroid carcinoma (PTC).Eligible patients received sorafenib 200 mg orally twice daily. Responses were assessed using Response Evaluation Criteria in Solid Tumors and adverse events were assessed periodically. The end points included response rate and progression-free survival.Nine patients with radioiodine-refractory PTC were enrolled in the study and treated for a minimum of 13 weeks. The objective partial response rate was 33%. The stable disease rate was 44%. The mean progression-free survival was 42 weeks (95% confidence interval, 29.5 to 53.9). Two patients showed disease progression, and one of them died at 4 months after beginning of treatment. There was a marked and rapid change in the serum thyroglobulin level after start of treatment, with a mean decrease of 60% within 12 weeks, consistent with radiographic findings. Although the types of toxicities were consistent with other sorafenib trials, their severity was relatively mild. None of the patients discontinued sorafenib or reduced their dose because of treatment-related adverse events.Sorafenib at a dose of 200 mg twice daily has a potential therapeutic effect and is well tolerated in Chinese patients with PTC and radioiodine-refractory pulmonary metastases. Further study is warranted with a larger cohort of patients.

The objective of this study was to study the characteristics of chyluria on radionuclide lymphoscintigraphy and evaluate the diagnostic value of radionuclide lymphoscintigraphy in chyluria. In this report radionuclide lymphoscintigraphy was performed in 41 cases of chyluria patients and the imaging results were retrospectively analyzed. Among 41 cases, 30 of them were caused by filariasis, 4 cases were secondary chyluria from abdomen surgery and 7 cases were caused by lymphangitis. Sixteen cases were proved as bilateral chyluria and 25 cases as unilateral chyluria by cystoscopy. The most common pattern of chyluria in radionuclide lymphoscintigraphy is that kidney or pelvis was imaged in the early phase of dynamic acquisition. In conclusion, radionuclide lymphoscintigraphy is a useful noninvasive method for detecting the origin site of chyluria, and for providing reliable information to perform safe operation.

Measurement of free plasma metanephrines (metanephrine and normetanephrine), usually performed by high-performance liquid chromatography with electrochemical detection (HPLC-ECD), has been recommended as the single biochemical test of choice for the diagnosis of pheochromocytoma. Alternatively, a widely available, simple means to measure these biomarkers with enzyme immunoassay (EIA) needs to be studied. The aim of this study was to investigate the diagnostic efficacy of such a method in comparison with (131)I-metaiodobenzylguanidine (MIBG) whole body scan (WBS) in patients with pheochromocytoma. We enrolled patients undergoing (131)I-MIBG WBS due to clinical findings suggestive of pheochromocytoma (n = 45), and patients with primary hypertension (n = 36). All subjects had blood tests for free plasma metanephrine (MN) and normetanephrine (NM) with a commercially available EIA kit. WBS was positive in 30 pheochromocytoma patients and negative in 15 refuted ones, with 100% accuracy. The sensitivity, specificity and accuracy of MN and NM in combination (either or both positive) were 96.7%, 86.3% and 90.1%, showing comparable diagnostic performance both to (131)I-MIBG WBS (all p0.1), and also to the same markers measured with HPLC-ECD reported in the literature. These results showed that the EIA method may be eligible as an alternative to HPLC-ECD for plasma metanephrine determination in the identification of pheochromocytoma.

The characteristics of lymphedema on radionuclide lymphoscintigraphy were studied, and the diagnostic value of radionuclide lymphoscintigraphy in lymphedema was evaluated. In this report radionuclide lymphoscintigraphy was performed in 110 cases of clinically suspected lymphedema. A retrospective study method was used to analyze the imaging results. The typical pattern of lymphedema on radionuclide lymphoscintigraphy was summarized. It was found that the characteristics of lymphedema on radionuclide lymphoscintigraphy were diverse. The most common pattern was increased radiotracer accumulation in the soft tissue and lymphatic webs. Surgery and infection dominated as the causes of lymphedema in this study. It was concluded that radionuclide lymphoscintigraphy is a useful noninvasive method for diagnosing lymphedema. It is easy to operate and provides reliable results.

To develop a radiopharmaceutical for apoptosis imaging, Annexin B1, a new Ca 2+ -dependent phosphatidylserine (PS)-binding protein, was directly radiolabeled with 99m Tc. This procedure yields up to 96% of radiochemical purity and higher radiolabeling efficiency. The preparation has been found to be sufficiently stable in vitro. Binding assay with human activated platelets indicated that 99m Tc-Annexin B1 retained its PS binding activity. Biodistribution in mice revealed that 99m Tc-Annexin B1 rapidly cleared from the blood and predominantly accumulated in the kidney. The increase in hepatic uptake in anti-Fas antibody treated mice correlated to histologic evidence of fulminant hepatic apoptosis. These data suggest that 99m Tc-Annexin B1 can be used as a novel radiotracer to detect apoptosis in vivo.

The significance of scrotum scintigraphy in differentiating acute testicular torsion from acute orchiepididymitis was evaluated. In this report, 49 patients with acute scrotal pain were examined with radionuclide scrotum scintigraphy and ultrasonography in parallel for comparison. Of 37 patients with decreased radioactivity in the abnormal side scrotum, 35 were diagnosed with testicular torsion surgically and the other 2 were diagnosed with indirect inguinal hernia. Only 17 among the 35 patients were diagnosed by ultrasonography as having testicular torsion. The remaining 12 patients with increased radioactivity in the abnormal side of the scrotum were all diagnosed with orchiepididymitis through conservative treatment and clinical follow-up, but only 8 of the 12 were correctly and exactly diagnosed by ultrasonography. In the process of diagnosing acute scrotal pain, radionuclide scrotum scintigraphy has obvious advantage over ultrasonography. It also has the advantage of being simple, fast and accurate but without any detrimental effect on the human body.