Quan-Yong Luo

Incremental Value of 131I SPECT/CT in the Management of Patients with Differentiated Thyroid Carcinoma

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.

The role of radionuclide lymphoscintigraphy in extremity lymphedema

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.

Response to Sorafenib at a Low Dose in Patients with Radioiodine-Refractory Pulmonary Metastases from Papillary Thyroid Carcinoma

BACKGROUNDnSorafenib 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 200u2009mg twice daily in patients with progressive radioiodine-refractory pulmonary metastases from papillary thyroid carcinoma (PTC).nnnPATIENTS AND METHODSnEligible patients received sorafenib 200u2009mg 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.nnnRESULTSnNine 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.nnnCONCLUSIONnSorafenib at a dose of 200u2009mg 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.

Pulmonary Metastases in Differentiated Thyroid Cancer: Efficacy of Radioiodine Therapy and Prognostic Factors

CONTEXTnData from a large cohort of patients with pulmonary metastases from differentiated thyroid cancer (DTC) were retrospectively analyzed.nnnOBJECTIVEnTo assess the effect of radioiodine therapy and investigate the prognostic factors of survival for patients with pulmonary metastasis secondary to DTC.nnnMETHODSnA total of 372 patients with pulmonary metastasis from DTC treated with (131)I entered the study. According to the results of (131)I whole-body scan (WBS), pulmonary metastases were classified as (131)I-avid and non-(131)I-avid. For patients with (131)I-avid lung metastases, treatment response was measured by three parameters: serum thyroglobulin (Tg) levels, chest computed tomography (CT) and post-therapeutic (131)I-WBS. Overall survival was calculated by the Kaplan-Meier method. Factors predictive of the outcome were determined by multivariate analyses.nnnRESULTSnAmong patients demonstrating (131)I-avid pulmonary metastases (256/372, 68.8%), 156 cases (156/256, 60.9%) showed a significant decrease in serum Tg levels after (131)I therapy and 138 cases (138/229, 60.3%) showed a reduction in pulmonary metastases on follow-up CT. A complete cure, however, was only achieved in 62 cases (62/256, 24.2%). Multivariate analysis showed that only age, the presence of multiple distant metastases and pulmonary metastatic node size were significant independent variables between the groups of (131)I-avid and non-(131)I-avid.nnnCONCLUSIONnThis study indicated that, most (131)I-avid pulmonary metastases from DTC can obtain partial or complete remission after (131)I therapy. Younger patients (<40 years old) with only pulmonary metastases and small (fine miliaric or micronodular) metastases appear to have relative favorite outcomes. Patients who do not respond to (131)I treatment have a worse prognosis.

Performance of 18F-fluoride PET or PET/CT for the detection of bone metastases: a meta-analysis.

Purpose This study aimed to evaluate the diagnostic accuracy of 18F-fluoride PET or PET/CT compared with 99mTc-MDP bone scintigraphy and 18F-FDG PET/CT in the detection of bone metastases. Patients and Methods An electronic search was conducted using PubMed/MEDLINE and EMBASE. The methodological quality of the included studies was assessed with Quality Assessment of Diagnostic Accuracy Studies 2. All analyses were performed on Stata version 12.0 and Meta-DiSc version 1.4. Results Twenty articles containing 1170 patients were identified. On a patient basis, the pooled sensitivity, specificity, and the area under the summary receiver operating characteristic curve of 18F-fluoride PET or PET/CT were 92% (95% confidence interval [CI], 89%–95%), 93% (95% CI, 91%–95%), and 0.985, respectively. On a lesion basis, the pooled sensitivity, specificity, and area under the summary receiver operating characteristic curve of 18F-fluoride PET or PET/CT were 87% (95% CI, 85%–88%), 95% (95% CI, 94%–96%), and 0.979, respectively. When compared with 99mTc-MDP bone scintigraphy, 18F-fluoride PET or PET/CT showed both higher sensitivity (96% vs. 88%, P = 0.002) and specificity (91% vs. 80%, P = 0.001). When compared with 18F-FDG PET/CT, 18F-fluoride PET/CT showed higher sensitivity (94% vs. 73%, P = 0.003), whereas no significant difference was observed in specificity (88% vs. 98%, P = 0.06). Conclusions 18F-fluoride PET or PET/CT has an excellent diagnostic capacity for the detection of bone metastases and shows advantages when compared with 99mTc-MDP bone scintigraphy and 18F-FDG PET/CT.

Brain Metastasis from Follicular Thyroid Carcinoma: Treatment with Sorafenib

BACKGROUNDnSorafenib 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.nnnPATIENT AND METHODSnA 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).nnnSUMMARYnSymptoms 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.nnnCONCLUSIONSnTargeted 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.

Comparison of free plasma metanephrines enzyme immunoassay with (131)I-MIBG scan in diagnosis of pheochromocytoma.

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 131I-metaiodobenzylguanidine (MIBG) whole body scan (WBS) in patients with pheochromocytoma. We enrolled patients undergoing 131I-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 131I-MIBG WBS (all p > 0.1), 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.

Localization of Concomitant Metastases to Kidney and Erector Spinae from Papillary Thyroid Carcinoma Using 131I-SPECT and CT

Whole-body I scanning plays an important role in the management of patients with differentiated thyroid cancer (DTC). Areas of uptake demonstrated following diagnostic or therapeutic I administration indicate the need for further I therapy (1,2). The minor sites of the distant metastases of DTC have been documented in the literature (3). A diversity of organs, such as brain, liver, kidney, skin, and muscle, has been reported. Here, we describe an incidentally detected kidney and erector spinae metastasis of papillary thyroid carcinoma (PTC) that was found by I–single photon emission computed tomography (I-SPECT) and computed tomography (CT) scans. Concomitant kidney and erector spinae metastasis of DTC is extremely rare in the clinical setting. A 29-year-old man who presented with locoregional lymph nodes and pulmonary metastases from PTC was treated with I for ablation of the postsurgical thyroid remnant and metastases. The posttherapy whole-body scan revealed two abdominal foci of I uptake in addition to the cervical and pulmonary uptake (Fig. 1). The cervical I uptake was due to residual thyroid tissue after surgery, and the pulmonary uptake was due to lung metastases confirmed by the chest CT scans. To differentiate the two abdominal foci of I uptake, the co-registered SPECT and low-dose CT scan was performed using GE Hawkeye Millennium VG. The coregistered SPECT=CT fusion images showed that the abdominal foci located in the area of right kidney (Fig. 2A, solid-line arrow in Fig. 1) and right low-back muscle (Fig. 2B, dashed-line arrow in Fig. 1), respectively. Further examination with high-resolution CT revealed solitary lesion on the upper pole of right kidney (Fig. 3A, B; solid-line arrow) and the right erector spinae (Fig. 3C, D; dashed-line arrow), respectively. The right erector spinae lesion was pathologically diagnosed as PTC metastasis by biopsy. The right renal lesion was suggested to be a thyroid carcinoma metastasis based on the CT and I scan findings. DTC usually remains localized to the thyroid gland. At the time of initial diagnosis, however, there may be cervical lymph node metastases and distant metastases. The most common sites of the distant metastases of DTC are the lungs and bones. Rare sites of distant metastases include the brain, liver, peritoneum, kidney, skin, and muscle (3). Clinically detectable differentiated metastatic thyroid carcinoma to the kidney and muscle is rare. To the best of our knowledge, fewer than 20 cases of renal metastases and 3 cases of muscular metastases from DTC were reported in the literature (4). Among them, only one elderly patient with poorly differentiated follicular thyroid carcinoma concomitantly metastasized to the kidney and thigh muscle (5). A unique case of unusual metastasis sites in the kidney and erector spinae from PTC occurring in a young man is herein presented. The practical interest in this case is that young patients with PTC may occasionally develop muscular, renal, and other unusual metastases concomitantly. It should be kept in mind that all suspected tumors are likely to be considered as potential metastases from thyroid carcinomas in the clinical setting. Integrated I-SPECT=CT has been found to have an additional value over planar imaging in patients with thyroid cancer for correct characterization of equivocal tracer uptake seen on planar imaging as well as for precise localization of malignant lesions in the neck, chest, and skeleton. SPECT=CT optimized the localization of I uptake to lymph node metastases versus remnant thyroid tissue, to lung versus mediastinal metastases, and to the skeleton (6). This case also demonstrated the clinical usefulness of I-SPECT=CT fusion images in the management of thyroid carcinoma. It may improve the anatomically limited interpretation of I scintigraphy alone for patients with DTC (7,8).

Clinical study of scrotum scintigraphy in 49 patients with acute scrotal pain: A comparison with ultrasonography

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.

Circulating Long Non-Coding RNAs Act as Biomarkers for Predicting 131I Uptake and Mortality in Papillary Thyroid Cancer Patients with Lung Metastases

Purpose: The aims of the current study were to explore plasma lncRNAs as a novel biomarker panel for the diagnosis of non-131I-avid lung metastases of PTC and to investigate the plasma lncRNA expression levels associated with survival in PTC patients with lung metastases. Methods: The expression of lncRNAs was examined using an lncRNA microarray chip. The lncRNAs with the most significant difference in expression between PTC patients with non-131I-avid lung metastases and PTC patients with 131I-avid lung metastases were verified by quantitative reverse-transcription polymerase chain reaction. The Kaplan-Meier method was used to determine whether the plasma lncRNA levels might be indicative of patient prognosis. Results: Compared with 131I-avid lung metastases, we discovered that two lncRNAs (ENST00000462717 andENST00000415582) were upregulated and two (TCONS_00024700 and NR_028494) were downregulated in the non-131I-avid lung metastases of PTC. Receiver operating characteristic curve (ROC) analyses indicated that the use of these four lncRNAs had high diagnostic sensitivity and specificity for predicting non-131I-avid lung metastases of PTC. The merged areas under the curve for ENST00000462717, ENST00000415582, TCONS_00024700,and NR_028494 in the training and validation sets were 0.890, 0.936, 0.975, and 0.918, respectively. Low (ENST00000462717 and ENST00000415582) and high plasma lncRNA levels(TCONS_00024700and NR_028494) were also found to be associated with better prognosis of PTC patients with lung metastases(P<0.001). Conclusions: ENST00000462717, ENST00000415582, TCONS_00024700, and NR_028494 may be used as novel and minimally invasive markers for the diagnosis and prognostic assessment of non-131I-avid lung metastases from PTC.