Iodine-131 metaiodobenzylguanidine (131I-mIBG) treatment in relapsed/refractory neuroblastoma.

BACKGROUND: I-meta-iodo-benzylguanidine (I-mIBG) therapy has been used in treatment of for advanced neuroblastoma for many years with promising results. There are several studies regarding predictors and outcomes of I-mIBG therapies in relapsed/refractory neuroblastoma patients. OBJECTIVE: To identify the predictors and outcomes of I-mIBG treatment in relapsed/refractory neuroblastoma. METHODS: This study was a retrospective review of 22 patients with high risk stage IV relapsed/refractory neuroblastoma who received at least one cycle of I-mIBG therapy. Patient' characteristics, hematologic toxicity, scintigraphic semi-quantitative scoring, and overall survival were recorded. Factors predicting survival were analyzed. RESULTS: Twenty-two patients (50% male) with mean age of 3.7 years (4.8 months to 8.3 years) received I-mIBG therapies at an average of 3.8 and mean dose of 136 mCi (5032 MBq) per treatment. Most common acute hematologic toxicity was thrombocytopenia. Overall 5-year survival rate was 37% (95% confidence interval: 16.3-58.0) and median survival time was 2.8 year (95% confidence interval: 1.38-6.34). Patients with rising Curie score of ≥25% upon the second therapy were major determinants of overall survival with poorer response to treatment. At least three treatments of I-mIBG were needed to identify some degrees of survival prolongation (crude hazard ratio: P-value = 0.003). Age, sex, metastatic status, and baseline Curie scoring system were good predictors associated with survival. Seven patients (32%) demonstrated objective responses. CONCLUSION: Despite multimodality therapy, high risk neuroblastoma had a propensity of treatment failure in terms of relapsed or refractory, with some objective responses after I-mIBG treatments. The declined or non-rising Curie score upon second post-treatment total body scan was an important predictor of survival and aided a decision whether or not to proceed with bone marrow transplantation.

Errors in Patient Positioning for Bone Mineral Density Assessment by Dual X-Ray Absorptiometry: Effect of Technologist Retraining.

Improper positioning is one of the factors that can lead to incorrect bone mineral density (BMD) results. This study aimed to assess the frequencies of erroneous positioning during three periods: before retraining of the technologists (BR), after retraining (AR), and at the current timepoint 8 years after retraining (C). The BMD images of the first 150 consecutive patients who underwent DXA of the lumbar spine and hip during each of the three periods were retrospectively reviewed. Patients were excluded if they had severe scoliosis, rendering proper positioning impossible. Each BMD image was assessed by an International Society of Clinical Densitometry certified clinical densitometrist who was blinded to the date of the initial examination. For the lumbar spine in the BR group, the criteria frequently not met were inclusion of both iliac crests (33.8%), straightness (30.3%), and midline positioning (20.4%); the respective frequencies were significantly reduced to 0.8%-5.6%, 2.1%-3.0%, and 0%-2.8% in the AR and C groups (p < 0.05). For the hip in the BR group, the criteria frequently not met were straightness (52.8%) and internal rotation (21.8%); the respective frequencies were significantly reduced to 0%-4.2% and 8.3%-8.4% in the AR and C groups (p < 0.05). Overall improper positioning in the BR group was 49.3% and 57.3% at the lumbar spine and the hip, respectively; the respective frequencies were reduced to 9.3% and 12.7% in the AR group, and to 2.7% and 7.3% in the C group. The least significant change values for the lumbar spine, femoral neck, and total hip also became smaller after retraining. Retraining the technologists improved patient positioning, as evidenced by the decreased frequencies of erroneous positioning and the improved least significant change values after the retraining.

Incidental Gallbladder Cancer Visualized From Posttreatment 131I Whole-Body Scan.

A 72-year-old woman with papillary thyroid cancer post-total thyroidectomy was referred for post-I treatment whole-body scan. Images revealed focal uptake within the gallbladder. Cholecystectomy was subsequently performed, and the pathology report showed well-differentiated adenocarcinoma. Given a history of papillary thyroid cancer, the iodine uptake was reasonably explained as metastasis; however, gallbladder metastasis was extremely infrequent. Literature described the incidental radioiodine retention in the gallbladder as false-positive findings, which can be normal variants or benign hepatobiliary conditions. Primary gallbladder malignancy could be counted for another possibility despite controversial mechanism of uptake.

Factors affecting disease-free status of differentiated thyroid carcinoma patients.

PURPOSE: The study aim was to assess factors that impact on the outcome of radioiodine therapy in patients diagnosed with differentiated thyroid carcinoma (DTC). MATERIALS AND METHODS: We performed a retrospective cohort study on 256 patients with DTC who underwent thyroidectomy and received radioiodine therapy during December 2003 to January 2012. All patients were followed up for at least 1 year. They were considered disease- free by the criteria of the revised American Thyroid Association Management Guideline for Patients with Thyroid nodules and DTC (ATA guideline 2009). RESULTS: On Cox univariate analysis, factors associated with disease-free status were age<45, stage I tumor, low risk group by histopathology, unifocal tumor involvement, stimulated serum Tg level at 1st dose of radioiodine therapy and no distant metastasis from 1st post-treatment WBS (post RxWBS). On multivariate analysis, stage I tumor and stimulated serum Tg level at 1st dose of radioiodine therapy<30 ng/mL were the significant prognostic factors that increased disease-free rate by 1.73 times and 2.60 times, respectively (P-value<0.05). CONCLUSIONS: Factors affecting the outcome of radioiodine therapy in our study were age, stage, risk of recurrence by histopathology, unifocal tumor involvement and 1st postRxWBS findings. From these factors, stage I tumor and stimulated serum Tg level at 1st dose of radioiodine therapy were independent prognostic factors that substantial increase the disease-free rate.

Unexpectedly expected fetal thyroid function on posttreated radioiodine (131I) SPECT/CT of a patient with differentiated thyroid cancer.

We present a 25-year-old woman who has a diagnosis of differentiated thyroid cancer, a 2.5-cm papillary carcinoma in the right lobe, and presence of minimal extrathyroid invasion. 131I ablation and/or treatment of 150 mCi was given orally 3 months after total thyroidectomy. A fetus with radioiodine uptake in the fetal thyroid was unsuspectedly detected by SPECT/CT after 131I treatment.