Primary presentation and clinical course of pediatric and adolescent patients with differentiated thyroid carcinoma after radioiodine therapy.

Introduction: Differentiated thyroid carcinoma (DTC) in childhood and during adolescence is extremely rare. Pediatric DTC commonly presents with advanced disease at diagnosis including a high prevalence of cervical lymph node metastases and pulmonary metastases. Studies in children with DTC are limited. Therefore, we aimed to evaluate the initial presentation, effectiveness of radioiodine therapy (RIT), and long-term outcome of prepubertal in comparison to pubertal/postpubertal patients. Methods: Eighty-five pediatric and young patients aged 6.4 to 21.9 years with histopathologically confirmed DTC were retrospectively included. They all underwent total thyroidectomy followed by RIT. Initial presentation and outcome of prepubertal and pubertal/postpubertal patients were compared 1 year after RIT, during follow-up, and at the last visit of follow-up. Results: Prepubertal patients presented with significantly higher T and M stages. One year after RIT, 42/81 (52%) patients still presented with evidence of disease (ED). During follow-up of a median of 7.9 years, prepubertal patients were less often in complete remission (58% vs. 82% in pubertal patients). At the last visit of follow-up, 19/80 (24%) patients still had ED without statistical differences between the two groups (42% prepubertal vs. 18% pubertal/postpubertal, p-value 0.06). None of our patients died disease-related over the observed period. Conclusion: Prepubertal children with DTC presented with a more advanced tumor stage at the initial presentation. During follow-up, they present more often with ED. However, at the end of our study, we did not observe statistically relevant differences in patient outcomes between the prepubertal and pubertal/postpubertal groups.

The diagnostic challenge of coexistent sarcoidosis and thyroid cancer - a retrospective study.

BACKGROUND: Sarcoid lesions may mimic metastatic disease or recurrence in thyroid cancer (TC) patients as both diseases may affect the lungs and lymph nodes. We present the first study to systematically evaluate the clinical course of patients with (TC) after adjuvant radioactive iodine therapy (RIT) and concomitant sarcoidosis of the lung or the lymph nodes. METHODS: We screened 3285 patients and retrospectively identified 16 patients with TC (11 papillary thyroid cancer (PTC), 3 follicular thyroid cancer (FTC), 1 oncocytic PTC, 1 oncocytic FTC) and coexisting sarcoidosis of the lung and/or the lymph nodes treated at our institute. All patients had undergone thyroidectomy and initial adjuvant RIT. Challenges in diagnosing and the management of these patients were evaluated during long term follow-up (median 4.9 years (0.8-15.0 years)). RESULTS: Median age at first diagnosis of TC was 50.1 years (33.0-71.5 years) and of sarcoidosis 39.4 years (18.0-63.9 years). During follow-up, physicians were able to differentiate between SA and persistent or recurrent TC in 10 of 16 patients (63%). Diagnosis was complicated by initial negative thyroglobulin (Tg), positive Tg antibodies and non-specific imaging findings. Histopathology can reliably distinguish between SA and TC in patients with one suspicious lesion. CONCLUSION: Physicians should be aware of the rare coexistence of sarcoidosis and TC. Lymphadenopathy and pulmonary lesions could be metastases, sarcoidosis or even a mix of both. Therefore, this rare patient group should receive a thorough work up including histopathological clarification and, if necessary, separately for each lesion.

Extended studies of the striatal uptake of 99mTc-NC100697 in healthy volunteers.

UNLABELLED: This study evaluates a new formulation of a (99m)Tc-labeled tropane derivate, (99m)Tc-NC100697, in a human volunteer study. METHODS: Eighty healthy subjects (39 females, 41 males) underwent MRI and SPECT (injected dose [mean +/- SD], 10.6 +/- 1.4 MBq/kg). Forty subjects were investigated 30, 90, 180, 240, 360, and 480 min after injection, and another 40 subjects were imaged 240 min after injection. Specific striatal binding was assessed using 3 different approaches: 3-dimensional volumes of interest (VOIs) drawn on the coregistered MRI scans, manually placed predefined 2-dimensional regions of interest (ROIs), and observer-independent fully automated 3-dimensional VOI analyses based on coregistration of scans with a mean template of controls. Specific striatal dopamine transporter (DAT) binding was estimated for cohorts of ages of 21-30, 31-40, 41-50, 51-60, 61-70, and 71-80 y. The relationship between age and DAT binding was analyzed with linear, "broken-stick," exponential, and logarithmic regression. RESULTS: Serial SPECT scans revealed increasing values of specific DAT binding over time. Consideration of all important variables suggests an optimum imaging time at 4 h after injection. Average DAT binding for the total population was 1.1 +/- 0.2 (striatum), 1.3 +/- 0.2 (caudate), and 1.1 +/- 0.2 (putamen), with mean putamen-to-caudate ratios of 0.83 +/- 0.08 (manual 2-dimensional ROI method). A significant age dependency of striatal DAT binding, best described by a broken-stick (break-point age, 48 y) or logarithmic regression (both r = 0.76), with a lower decline observed in older than in younger subjects. Female subjects presented with slightly higher binding ratios than male subjects, more pronounced in pre- than in postmenopausal women. There was a high correlation between the 3 semiquantitative evaluations. CONCLUSION: The current study has demonstrated the effective use of (99m)Tc-NC100697 for estimating presynaptic striatal DAT binding. The comparison of different semiquantification methods showed that in clinical routine work, this tracer can be reliably evaluated without individual MRI data. Age and a slight sex dependency (especially in premenopausal women) of (99m)Tc-NC100697 binding should be taken into consideration. The data generated in this phase 1 study provides a basis for an age- and sex-matched normal database.