Saulo Purisch

Ultrasonographic Differentiation Between Metastatic and Benign Lymph Nodes in Patients With Papillary Thyroid Carcinoma

The purpose of this study was to evaluate the ultrasonographic characteristics of metastatic lymph nodes in patients with papillary thyroid carcinoma.

Preparation with Recombinant Human Thyroid-Stimulating Hormone for Thyroid Remnant Ablation with 131I Is Associated with Lowered Radiotoxicity

Preparation with recombinant human thyroid-stimulating hormone (rhTSH) for thyroid remnant ablation results in lower extrathyroidal radiation than does hypothyroidism. The objective of this prospective study was to compare the damage caused by 131I (3.7 GBq) when these 2 preparations are used. Methods: Ninety-four consecutive patients who underwent total thyroidectomy and remnant ablation with 3.7 GBq of 131I were studied. Thirty patients (group A) received rhTSH, and 64 (group B) were prepared by levothyroxine withdrawal. Damage to salivary glands, ovaries, and testes; hematologic damage; and oxidative injury were evaluated by measurement of serum amylase, follicle-stimulating hormone (FSH), complete blood count, and plasma 8-epi-PGF2α before and after radioiodine. The 2 groups were similar in sex, age, and the results of baseline assessment. Results: The rate of successful ablation (stimulated thyroglobulin level < 1 ng/mL and negative findings on neck ultrasonography) was 90% in group A and 80% in group B. Considering only patients with a preablation thyroglobulin level greater than 1 ng/mL, these rates were 80% and 70.6%, respectively. Only 1 patient (3.3%) reported transient headaches with rhTSH. Elevated FSH levels after therapy were observed in 4 of 9 (44%) men in group A versus 16 of 18 (89%) in group B (P < 0.03), with a mean increase of 105% versus 236% (P < 0.001), respectively. In women, elevated FSH was observed in 1 of 13 (7.7%) patients in group A versus 6 of 30 (20%) in group B (P = 0.4), with a mean increase of 65% versus 125% (P < 0.001). Thrombocytopenia or neutropenia occurred in 2 of 28 (7%) patients in group A versus 12 of 56 (21.4%) in group B (P = 0.1), with a mean decrease of 20% versus 45% and 25% versus 52% (P < 0.01) for neutrophils and platelets, respectively. Hyperamylasemia and symptoms of acute sialoadenitis occurred in 11 of 30 (36.6%) versus 48 of 60 (80%) (P < 0.001) and in 9 of 30 (30%) versus 35 of 60 (58.3%) (P = 0.01), respectively. 8-Epi-PGF2α was found to be elevated after 131I in 14 of 25 (56%) patients in group A versus 45 of 45 (100%) in group B (P < 0.001), with a mean increase of 60% versus 125% (P < 0.001). Conclusion: The lower radiotoxicity with rhTSH, suggested in dosimetry studies, was confirmed in the present prospective investigation, and this advantage occurred without compromising the efficacy of treatment.

Natural History of Mild Subclinical Hypothyroidism: Prognostic Value of Ultrasound

BACKGROUND Clinical repercussions, progression to overt hypothyroidism, and treatment benefits have been well established in patients with subclinical hypothyroidism (SCH) and TSH >10 mIU/L. In contrast, these aspects of the disease are poorly understood in patients with even milder SCH as defined by TSH < or = 10 mIU/L and normal thyroid hormone levels. Therefore, we sought to evaluate the natural history of this milder form of SCH (TSH < or =10 mIU/L with normal thyroid hormone levels) in adult women patients. PATIENTS One hundred seventeen patients with TSH levels ranging from 5 to 10 mIU/L and normal free T4, without a previously known history of thyroid disease, were followed for a period of 3 years and had two consecutive assessments. RESULTS Sixty patients tested positive for antithyroperoxidase antibodies (TPOAb) and 36 were TPOAb negative but had diffuse hypoechogenicity on thyroid ultrasound (US). Twenty-one patients were TPOAb negative and had normal US. During follow-up, 20.5% of the patients had spontaneous normalization of their TSH, 27.3% required replacement therapy with levothyroxine (L-T4) because of progression to overt hypothyroidism or persistence of serum TSH >10 mIU/L, and 52.1% continued to meet the criteria for mild SCH (persistence of TSH < or =10 mIU/L). If the patients were classified into two groups, one with positive TPOAb and/or US alteration and the other with testing negative for TPOAb and not having US alteration, the first group had a greater progression toward overt hypothyroidism (31.2% vs. 9.5%, respectively) and a lower rate of normalization of TSH (15.6% vs. 43% respectively). These rates were similar in TPOAb-positive patients and patients with negative TPOAb but with positive US. CONCLUSIONS Most patients with SCH and TSH < or = 10 mIU/L do not progress to overt hypothyroidism. The presence of chronic thyroiditis as demonstrated by US increases the evolution of SH to overt hypothyroidism or more severe SCH and thus the need for L-T4 treatment. US findings are important in determining the prognosis of mild SCH.

Post I-131 therapy scanning in patients with thyroid carcinoma metastases: an unnecessary cost or a relevant contribution?

Rationale: In patients with elevated serum thyroglobulin (Tg) and a negative whole-body scan (WBS), posttherapy scanning can reveal metastases in many cases and is therefore recommended. In contrast, the routine use of posttherapy scanning is questioned. Materials and Methods: One hundred six patients with differentiated thyroid carcinoma had pre- and posttherapy scanning, with metastatic uptake on the diagnostic scan and were divided into 2 groups: 60 patients assessed on first ablation after thyroidectomy and 46 patients with tumor persistence or recurrence after initial ablative therapy. Data modifying the disease stage or treatment were considered to be clinically relevant. Results: Posttherapy scanning on first ablation changed the disease stage in 8.3% of the patients and therapeutic approach in another 15%, and provided clinically relevant information for 26% of patients with 1 previous ablation. Even when excluding cases whose lesions were known by the time of the first postablative scan, the therapeutic approach was influenced by posttherapy scanning in 15.6% of the patients. Only 4 of 211 metastases detected on pretherapy WBS did not appear on postablative scans. Conclusions: Posttherapy scanning provides important information, even in patients whose pretherapy WBS is positive for metastases, with this approach being useful both during the first ablation and subsequent treatment.

Antithyroglobulin antibodies in patients with differentiated thyroid carcinoma: methods of detection, interference with serum thyroglobulin measurement and clinical significance

Antithyroglobulin antibodies (TgAb) were measured using a chemiluminescent immunoassay (ICMA) and an agglutination test. TgAb laboratory and clinical interference with Tg measurements were assessed. The course of TgAb concentration and disease status were compared during 3 years after initial treatment. The agglutination test failed to detect all titers < 10 IU/mL (ICMA). Interference from TgAb was common at high titers, but even low antibody titers (< 5 IU/mL) were able to interfere with Tg measurement. Cases of distant metastases with undetectable Tg (by IRMA) and those apparently free of disease and without thyroid remnants with Tg> 2 ng/ml (by RIA) were identified among patients with TgAb. The exogenous Tg recovery test was normal (> 80%) by the two methods in 22% of patients with TgAb and confirmed laboratory interference. Absence of reduction in TgAb levels was a marker of persistent disease. In conclusion, TgAb should be determined by immunoassays; interference with Tg measurements occurred mainly but not always at high concentrations, with a normal Tg recovery test not excluding this interference. The behavior of TgAb is related to disease persistence or cure.

Sonography in the Diagnosis of Cervical Recurrence in Patients With Differentiated Thyroid Carcinoma

Objective. To determine the sensitivity of thyroglobulin (Tg), iodine scanning, and sonography in the diagnosis of cervical recurrence of thyroid cancer. Methods. This prospective study assessed 81 patients with cervical metastases or extrathyroid invasion at first appearance who underwent clinical examination, scanning, measurement of Tg after thyroxine withdrawal, and sonography about 8 months after thyroidectomy followed by radioiodine treatment. Only patients without distant metastases and without anti‐Tg antibodies were included. Results. Fifty patients showed persistence of the disease in the cervical region, with only 16% of them having had a suspicion on clinical examination, 33 with Tg levels of 2 ng/mL or greater (66% sensitivity), and 29 with positive scan findings (58% sensitivity). A combination of the 2 methods detected disease in 40 (80%) of 50 patients but failed to show 20% of cases that were identified by sonography and confirmed by fine‐needle aspiration. Sonography had sensitivity of 96%. Specificity values for Tg, iodine scanning, and sonography were 80.6%, 90.3%, and 87%, respectively. Conclusions. Classic follow‐up methods may not detect cervical disease in some patients with differentiated thyroid carcinoma, and sonography is necessary even in patients apparently free of the disease.

Thyroglobulin before Ablation and Correlation with Posttreatment Scanning

Objectives/Hypothesis: To determine the usefulness of thyroglobulin (Tg) before ablation and the correlation with posttreatment scanning in patients with thyroid carcinoma.

Is stimulation of thyroglobulin (Tg) useful in low‐risk patients with thyroid carcinoma and undetectable Tg on thyroxin and negative neck ultrasound?

Objective  To determine the usefulness of thyroglobulin (Tg) stimulation in low‐risk patients with undetectable Tg on T4 and negative neck ultrasound (US) after initial therapy of thyroid carcinoma.

Ultrasonographic characteristics as a criterion for repeat cytology in benign thyroid nodules

OBJECTIVE To report the results of repeat fine-needle aspiration cytology (FNAC) in thyroid nodules with an initial benign cytological diagnosis that grow during follow-up and/or present suspicious ultrasonographic characteristics. SUBJECTS AND METHODS The sample consisted of 456 patients with 895 nodules. FNAC was repeated after 12 to 18 months in the case of nodules with suspicious ultrasonographic characteristics, irrespective of growth, and when the nodules showed significant growth. RESULTS Among the 895 nodules examined, 102 (11.4%) presented suspicious ultrasonographic characteristics. The second FNAC revealed malignancy in 18 (17.6%) nodules, including 20% (2/10) of those showing growth and 17.4% (16/92) that did not. Seventy-six (9.6%) of 793 nodules without suspicious characteristics presented growth. Only one case (1.3%) of malignancy was diagnosed by repeat FNAC. CONCLUSIONS The study suggests ultrasonographic characteristics rather than growth as a criterion for repeat FNAC in the case of nodules with an initial benign cytological diagnosis.

Latent autoimmune diabetes in adults (LADA): usefulness of anti-GAD antibody titers and benefit of early insulinization

OBJECTIVE To determine the clinical and laboratory parameters and the progression to insulin requirement in two groups of LADA patients separated according to GADA titers, and to evaluate the benefit of early insulinization in patients at high risk of premature beta-cell failure (high GADA titers). METHODS Among the diabetic adults seen at our service and screened for GADA at diagnosis, 54 were diagnosed with LADA and classified as having low (> 1 U/ml and < 17.2 U/ml) or high (> 17.2 U/ml) GADA titers. Fifty-four patients with type 2 diabetes (GADA-) were selected for comparison. In addition, 24 patients who had GADA titers > 20 U/ml and who were not initially insulinized were compared to 16 patients who were insulinized at diagnosis. RESULTS Insulin resistance was higher in the GADA- group, followed by patients with low GADA titers. BMI and the frequency of arterial hypertension, elevated triglycerides and reduced HDL cholesterol were lower in the high GADA+ group, with no difference between the GADA- or low GADA+ groups. The high GADA+ group showed a greater reduction and lower levels of C-peptide and required insulin earlier during follow-up. Patients with GADA titers > 20 U/ml and insulinized early presented no significant variation in C-peptide levels, had better glycemic control and required a lower insulin dose than patients who were insulinized later. CONCLUSION We agree that patients with LADA should be differentiated on the basis of GADA titers and that patients with GADA titers > 20 U/ml benefit from early insulinization.