Sergio Suriano

Thyroglobulin measurement before rhTSH‐aided 131I ablation in detecting metastases from differentiated thyroid carcinoma

Aim  Thyroidectomy followed by administration of large activities of 131‐iodine (131I) is the treatment of choice for differentiated thyroid carcinoma (DTC). The serum thyroglobulin (Tg) measurement during hypothyroidism (offT4‐Tg), just before radioiodine thyroid ablation, has proved to be effective for predicting persistent/recurrent disease. However, the Tg measurement cannot be used as a corresponding value for pre‐ablative offT4‐Tg when recombinant human TSH (rhTSH) is used as stimulus before treatment. The present study was undertaken to evaluate if post‐thyroidectomy Tg values, measured before rhTSH‐stimulated radioiodine ablation is of prognostic value in patients affected by DTC.

Relationship between serum thyroglobulin and 18FDG-PET/CT in 131I-negative differentiated thyroid carcinomas.

The purpose of this study was to assess the relationship between [18F]‐fluorodeoxyglucose (18FDG)‐positron emission tomography/CT (18FDG‐PET/CT) and serum thyroglobulin (Tg) in patients with recurrent differentiated thyroid carcinoma (DTC).

99mTc-sestamibi scanning in thyroid nodules with nondiagnostic cytology

Our aim in this study was to assess the relevance of 99mTc‐sestaMIBI (MIBI) scan in the diagnostic evaluation of thyroid nodules with nondiagnostic cytology.

Undetectable thyroglobulin in patients with differentiated thyroid carcinoma and residual radioiodine uptake on a postablation whole-body scan.

Aim: To assess the impact of laboratory interferences and pitfalls in producing falsely undetectable Tg in differentiated thyroid carcinoma (DTC) patients with residual iodine-avid thyroid tissue on a posttreatment whole-body scan (PT-WBS). Methods: From 298 consecutive patients with histologically proven DTC, 47 patients (16%) with undetectable serum Tg but residual 131I uptake on a PT-WBS were selected. Interferences from antithyroglobulin antibodies (TgAb), heterophile antibodies, and hook-effects were screened; in the remaining samples, serum Tg was measured in 3 different immunoassays. Results: Of 47 patients, 11 (23%) showed interference from either thyroglobulin antibodies (n = 10) or heterophile antibodies (n = 1). Among the 36 remaining patients, 18 showed detectable Tg levels after retesting using a different immunoassay, whereas the remaining 18 patients also showed detectable Tg levels in a third Tg immunoassay. However, only 7 patients showed a detectable Tg in both secondarily used assays. Tg levels remained undetectable in all methods in 9 patients (19%) even after extensive laboratory work-up and despite the presence of 131I-avid tissue found in PT-WBS. Conclusions: A careful assessment of interferences in Tg measurement significantly reduced the occurrence of undetectable Tg among patients with 131I uptake in PT-WBS. However, such extensive assessment is difficult in clinical practice and one-fifth of patients still had undetectable Tg in multiple assays despite an intensive laboratory work-up. A benchmark between 131I imaging and Tg measurement authenticates the interpretation of Tg measurements and, consequently, remains of pivotal value by authenticating the use of serum Tg during further follow-up of DTC patients.

Lymph Node Thyroglobulin Measurement in Diagnosis of Neck Metastases of Differentiated Thyroid Carcinoma

Aim. Enlarged cervical lymph nodes (LNs) in patients with thyroid cancer are usually assessed by fine-needle aspiration cytology (FNAC). Thyroglobulin (Tg) is frequently elevated in malignant FNAC needle wash specimens (FNAC-Tg). The objectives of the study were to (1) determine an appropriate diagnostic cut-off for FNAC-Tg levels (2) compare FNAC and FNAC-Tg results in a group of 108 patients affected by differentiated thyroid carcinoma (DTC). Methods. A total of 126 consecutive FNACs were performed on enlarged LNs and the final diagnosis was confirmed by surgical pathology examination or clinical follow-up. The best FNAC-Tg cut-off level was selected by receiver operating curve analysis, and diagnostic performances of FNAC and FNAC-Tg were compared. Results. The rate of FNAC samples adequate for cytological examination was 77% in contrast FNAC-Tg available in 100% of aspirates (P < .01). The sensitivity, specificity, and accuracy of FNAC were 71%, 80%, 74%, 100%, 80%, and 94%, respectively. The most appropriate cut-off value for the diagnosis of thyroid cancer metastatic LN was 1.1 ng/mL (sensitivity 100%, specificity 100%). Conclusions. The diagnostic performance of needle washout FNAC-Tg measurement with a cut-off of 1.1 ng/mL compared favorably with cytology in detecting DTC node metastases.

Spurious hypercalcitoninemia and heterophilic antibodies in patients with thyroid nodules

The purpose of our study was to examine the prevalence of significant heterophilic antibody (HAb) interferences in serum calcitonin measurement in a large cohort of patients with thyroid nodules.

18FDG-positron emission tomography/computed tomography (PET/CT) scanning in thyroid nodules with nondiagnostic cytology

Objective  To assess the role of positron emission tomography/computed tomography (PET/CT) scans with 18FDG (18FDG‐PET/CT) in the evaluation of thyroid nodules with nondiagnostic cytology.

18F-FDG uptake changes in liver and mediastinum during chemotherapy in patients with diffuse large B-cell lymphoma.

Purpose The main objective of this study was to assess the intrasubject and intersubjects variability of 18F-FDG uptake in liver (LIV) and mediastinum (MBP) among patients with diffuse large B-cell lymphoma (DLBCL), treated with different chemotherapy regimens. Patients and Methods Fifty patients with DLBCL who underwent 18F-FDG PET/CT scan at baseline, after a few cycles of therapy (interim PET) and on completion of therapy (final PET), were enrolled retrospectively. SUVmean and SUVmax values for LIV and MBP, their differences (LIV − MBP SUVmean and LIV − MBP SUVmax), and their changes were calculated, respectively. Results Liver uptake significantly increased in the interim in comparison with baseline and final PET, respectively, whereas MBP activity remained stable during chemotherapy. The intersubject variability of 18F-FDG uptake in LIV and MBP ranged from 20.2% to 25.4%. Conclusions The variability of the LIV uptake during chemotherapy should be taken into account when this parameter is used to score the interim PET scan and to make decisions in defining response-adapted therapeutic strategies. Vice versa, the stability of MBP activity during therapy provides a more reliable benchmark for the response assessment. Finally, the intersubjects variability of both parameters should be considered when the visual evaluation of the interim PET is performed by point score models.

POSTSURGICAL THYROID REMNANT ESTIMATION BY 99mTc-PERTECHNETATE SCINTIGRAPHY PREDICTS RADIOIODINE ABLATION EFFECTIVENESS IN PATIENTS WITH DIFFERENTIATED THYROID CARCINOMA

The purpose of this study was to evaluate the relationship between postsurgical neck 99mtechnetium (99mTc)‐pertechnetate uptake and the rate of successful remnant ablation after radioiodine treatment in patients with differentiated thyroid carcinoma (DTC).

Graves' disease, thymus enlargement, and hypercalcemia.

To the Editor: A previously healthy 32-year-old man presented with dyspnea on exertion. Chest radiography showed mediastinal enlargement without pulmonary abnormalities. Magnetic resonance imaging ...