Daniel S. Duick

American Association of Clinical Endocrinologists, Associazione Medici Endocrinologi, and European Thyroid Association Medical Guidelines for Clinical Practice for the Diagnosis and Management of Thyroid Nodules

American Association of Clinical Endocrinologists, Associazione Medici Endocrinologi, and European Thyroid Association medical guidelines for clinical practice for the diagnosis and management of thyroid nodules are systematically developed statements to assist health care professionals in medical decision making for specific clinical conditions. Most of the content herein is based on literature reviews. In areas of uncertainty, professional judgment was applied. These guidelines are a working document that reflects the state of the field at the time of publication. Because rapid changes in this area are expected, periodic revisions are inevitable. We encourage medical professionals to use this information in conjunction with their best clinical judgment. Any decision by practitioners to apply these guidelines must be made in light of local resources and individual patient circumstances.

American Association of Clinical Endocrinologists, Associazione Medici Endocrinologi, and European Thyroid Association Medical guidelines for clinical practice for the diagnosis and management of thyroid nodules: executive summary of recommendations.

American Association of Clinical Endocrinologists, Associazione Medici Endocrinologi, and European Thyroid Association Medical Guidelines for Clinical Practice for the Diagnosis and Management of Thyroid Nodules are systematically developed statements to assist health care professionals in medical decision making for specific clinical conditions. Most of the content herein is based on literature reviews. In areas of uncertainty, professional judgment was applied.These guidelines are a working document that reflects the state of the field at the time of publication. Because rapid changes in this area are expected, periodic revisions are inevitable. We encourage medical professionals to use this information in conjunction with their best clinical judgment. Any decision by practitioners to apply these guidelines must be made in light of local resources and individual patient circumstances.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS, AMERICAN COLLEGE OF ENDOCRINOLOGY, AND ASSOCIAZIONE MEDICI ENDOCRINOLOGI MEDICAL GUIDELINES FOR CLINICAL PRACTICE FOR THE DIAGNOSIS AND MANAGEMENT OF THYROID NODULES - 2016 UPDATE

Thyroid nodules are detected in up to 50 to 60% of healthy subjects. Most nodules do not cause clinically significant symptoms, and as a result, the main challenge in their management is to rule out malignancy, with ultrasonography (US) and fine-needle aspiration (FNA) biopsy serving as diagnostic cornerstones. The key issues discussed in these guidelines are as follows: (1) US-based categorization of the malignancy risk and indications for US-guided FNA (henceforth, FNA), (2) cytologic classification of FNA samples, (3) the roles of immunocytochemistry and molecular testing applied to thyroid FNA, (4) therapeutic options, and (5) follow-up strategy. Thyroid nodule management during pregnancy and in children are also addressed. On the basis of US features, thyroid nodules may be categorized into 3 groups: low-, intermediate-and high-malignancy risk. FNA should be considered for nodules ≤10 mm diameter only when suspicious US signs are present, while nodules ≤5 mm should be monitored rather than biopsied. A classification scheme of 5 categories (nondiagnostic, benign, indeterminate, suspicious for malignancy, or malignant) is recommended for the cytologic report. Indeterminate lesions are further subdivided into 2 subclasses to more accurately stratify the risk of malignancy. At present, no single cytochemical or genetic marker can definitely rule out malignancy in indeterminate nodules. Nevertheless, these tools should be considered together with clinical data, US signs, elastographic pattern, or results of other imaging techniques to improve the management of these lesions. Most thyroid nodules do not require any treatment, and levothyroxine (LT4) suppressive therapy is not recommended. Percutaneous ethanol injection (PEI) should be the first-line treatment option for relapsing, benign cystic lesions, while US-guided thermal ablation treatments may be considered for solid or mixed symptomatic benign thyroid nodules. Surgery remains the treatment of choice for malignant or suspicious nodules. The present document updates previous guidelines released in 2006 and 2010 by the American Association of Clinical Endocrinologists (AACE), American College of Endocrinology (ACE) and Associazione Medici Endocrinologi (AME).

Thyroid ultrasound and ultrasound-guided FNA

Thyroid ultrasound and ultrasound-guided FNA / , Thyroid ultrasound and ultrasound-guided FNA / , کتابخانه دیجیتال جندی شاپور اهواز

Significance of radioiodine uptake at 72 hours versus 24 hours after pretreatment with recombinant human thyrotropin for enhancement of radioiodine therapy in patients with symptomatic nontoxic or toxic multinodular goiter.

OBJECTIVE To report the effects of pretreatment with recombinant human thyrotropin (rhTSH) on radioiodine uptake (RAIU) and subsequent radioiodine therapy in 30 patients with symptomatic nontoxic or toxic multinodular goiter. METHODS Patients received a single injection of rhTSH (0.1 mg in 21 and 0.3 mg in 9 patients). Thyroid function tests were performed before and 72 hours after rhTSH administration. Both 4-hour and 24-hour RAIU studies were done after rhTSH administration and repeated at 48 to 52 hours and at 72 hours, respectively. Then all patients were treated with 30 mCi of 131 I. RESULTS All study patients experienced symptomatic relief by 1 to 2 months. In addition to the previously reported twofold increase over the baseline RAIU at 24 hours, we found that a second 24-hour RAIU showed a further twofold increase (quadrupling of the RAIU over baseline) at 72 hours after administration of 0.1 mg of rhTSH (from 22% to 43%; P<0.001) and 0.3 mg of rhTSH (from 16% to 37%; P = 0.002), with no significant difference between doses on the RAIU at 24 hours or at 72 hours. Additionally, the RAIU value at 4 hours and 52 hours after administration of 0.1 mg and 0.3 mg of rhTSH revealed a fourfold increase for each dose--from 7% to 28% (P<0.001) and from 5% to 21% (P = 0.002), respectively. CONCLUSION In patients with symptomatic toxic or nontoxic multinodular goiter, 0.1 mg and 0.3 mg of rhTSH were equally efficacious at inducing a quadrupling of the low or low-normal baseline RAIU values at 72 hours after injection. Subsequent radioiodine therapy alleviated compressive and thyrotoxic symptoms in all 30 treated patients. Future studies should help determine doses of rhTSH and radioiodine therapy that are optimal in iodine-sufficient and insufficient regions of the world.

IDENTIFYING PREDIABETES USING FASTING INSULIN LEVELS

OBJECTIVE To determine whether patients with prediabetes can be accurately and easily identified in clinical settings using a predictive clinical and laboratory model. METHODS This retrospective study examined demographic and laboratory data from patients who had undergone 2-hour glucose testing for suspected prediabetes or diabetes between 2000 and 2004. Patients who met the diagnostic criteria for diabetes mellitus were excluded. Prediabetes was defined as a fasting glucose concentration > or = 100 mg/dL and < or = 125 mg/dL or a 2-hour postprandial glucose concentration > or = 140 mg/dL and < 200 mg/dL. Multivariate logistic regression was conducted to identify calculated or measured clinical and laboratory attributes that predict the presence of prediabetes, including fasting insulin quartiles, homeostasis model assessment of insulin resistance (HOMA-IR), and quantitative insulin sensitivity check index. RESULTS Of 965 patients, 287 (29.7%) had prediabetes. The study population primarily consisted of white, obese, female patients. A multivariate model revealed that compared with the referent lowest quartile of fasting insulin (mu = 4.9 [+/-SD] +/-1.2 microIU/mL), subsequent insulin quartiles increased the likelihood of identifying prediabetes (quartile 2: mu = 8.0 +/-0.8 microIU/mL, odds ratio [OR] = 2.076, confidence interval [CI] = 1.241-3.273; quartile 3: mu = 12.2 +/-1.7 microIU/mL, OR = 3.151, CI = 1.981-5.015; quartile 4: mu = 25.9 +/-12.4 microIU/mL, OR = 5.035, CI = 3.122-8.122). Older age and increased diastolic blood pressure also contributed modestly to this model. Further analysis using the area under the curve revealed that at a fasting insulin level > 9.0 microIU/mL, prediabetes would be correctly identified in 80% of affected patients. A second model revealed that increased HOMA-IR index (OR = 1.303, CI = 1.205-1.410) and older age (OR = 1.037, CI = 1.024-1.05) predicted prediabetes. CONCLUSIONS The most robust model, which used fasting insulin levels, may provide the most utility as a clinical tool because the highest quartiles suggest significantly greater likelihood of identifying prediabetes.

Appropriate administration of fine-needle aspiration (FNA) biopsy on selective parathyroid adenomas is safe.

The article by Norman et al. (1) titled ‘‘Diagnostic aspiration of parathyroid adenomas causes severe fibrosis complicating surgery and final histologic diagnosis’’ raises several concerns as described below. The collective reference of large bore needles such as 18–22gauge needles along with fine bore needles (25–27 gauge) is inaccurate and misleading. Despite the obvious differences in the outcomes, the authors conclude by calling for cessation of the practice of fine-needle aspiration (FNA) of suspected parathyroid adenomas. The distinction in the size of the needles should have been defined in the study particularly since comparisons in the outcomes between the needles have been made. Large bore needle biopsies are associated with greater risk of bleeding in the case of thyroid biopsy (2,3). The use of large bore needles for performing biopsy on endocrine glands in the neck has largely been abandoned. In contrast, a quarter century use of FNA of the thyroid gland using fine bore needles has a remarkable safety record and utility (4). It is also evident that the study is retrospective where several operators using differing techniques have been involved and hence the outcomes cannot be compared between the techniques or the needles used (1). Also, the number of passes performed is clearly far too many. We have never found the need for any more than one or two passes with 27gauge needles on suspected parathyroid adenomas, and none of these subjects developed fibrosis (5). In this reported series of patients who developed fibrosis reaction, none of the subjects received the 1 to 2 passes that are sufficient to obtain adequate samples (1). In the majority of subjects (17=30), either large bore needles were used or the needle size was not known. Also, the 5 out of 13 subjects in whom fibrosis followed the use of 25to 27-gauge needles have received an excessive number of attempts at aspiration (mean number of passes1⁄4 6) per individual procedure (1). To summarize, what Norman et al. has reported in this journal is a surgical series of parathyroid adenomas that have undergone traumatic biopsies by several operators (number of FNAs performed1⁄4 30) of unknown skill levels and possibly practicing different aspirating techniques. Moreover, the use of large bore needles along with the excessive number of passes induced tumor damage and bleeding leading to delayed macroscopic and microscopic fibrosis reaction (1). Despite the administration of what appears to be traumatic biopsy techniques with excessive number of passes using mostly large bore needles, only 2 of the 30 patients even showed fibrosis during surgery when 27-gauge needles had been used. The safety of FNA of parathyroid adenomas using fine bore needles has been observed by several independent groups of researchers (5–8). This fact has been overlooked and not discussed in a balanced manner by Norman et al. We agree that all parathyroid adenomas visualized by ultrasound (US) may not need biopsy confirmation. We find biopsy confirmation to be especially valuable in Tc99 MIBI negative subjects, in patients with multiple enlarged parathyroid glands, prior failed surgery, differentiating parathyroid adenomas from posterior thyroid nodules, atypical location, and nonfunctioning parathyroid incidentalomas. As and added benefit, the use of US localization also enables the identification of incidental thyroid tumors and cancer that coexist in patients with primary hyperparathyroidism that can effectively be addressed during the same surgery (5). Minimally invasive parathyroid surgery is not applicable in those patients who have coexisting thyroid cancers or nodules with suspicious cytology. The authors’ concern that FNA might cause false positive histology findings, suggesting carcinoma is farfetched since that diagnosis would be suspected based on clinical and biochemical findings prior to the surgery. We conclude that US evaluation of parathyroid adenomas with biopsy confirmation when used appropriately in select cases is a safe technique that yields valuable information and, therefore, cannot be discarded.

Ultrasound-Guided Fine-Needle: Aspiration of Thyroid Nodules

There are multiple benefits in performing a diagnostic ultrasound examination prior to a thyroid nodule fine-needle aspiration (FNA). These benefits include determining the size and position of a nodule, which allows better selection of needle length and needle size. In patients with a multinodular goiter, ultrasound assures biopsy of the dominant nodule or the nodules most likely to be malignant—those having microcalcifications, increased vascularity, marked hypoechogenicity, blurred irregular borders, or other characteristics associated with malignancy. Finally, ultrasound may redirect the FNA to other areas of suspicion, such as an enlarged, suspicious lymph node or an incidental parathyroid adenoma. Once a physician acquires the skill to perform thyroid ultrasonography, it is a simple progression to combine the two procedures into an ultrasound-guided FNA (UGFNA).

Ultrasound-Guided Fine-Needle Biopsy of Thyroid Nodules

There are multiple benefits in performing a diagnostic neck ultrasound examination prior to a thyroid nodule fine-needle aspiration (FNA). These benefits include confirming that a biopsy is required and determining the size and position of a nodule, which allows better selection of needle length and needle size. In patients with a multinodular goiter, ultrasound assures biopsy of the dominant nodule or the nodules most likely to be malignant—those having microcalcifications, increased vascularity, marked hypoechogenicity, blurred irregular borders, or other characteristics associated with malignancy. Finally, ultrasound may redirect the FNA to other areas of suspicion, such as an enlarged, suspicious lymph node or identify an incidental parathyroid adenoma. Once a physician acquires the skill to perform diagnostic neck ultrasonography, it is a simple progression to combine the two procedures into an ultrasound-guided FNA (UGFNA).

Ultrasound-Guided FNA and Molecular Markers for Optimization of Thyroid Nodule Management

Thyroid nodules are a common clinical problem. The prevalence range by palpation is 3–7 %. Imaging with thyroid ultrasonography detects numerous additional nodules with prevalence rate ranging from 20 to 76 % of the general adult population. The prevalence risk for malignancy in a thyroid nodule is less than 5 %. A risk-based strategy has been developed to evaluate thyroid nodules and includes: clinical history and physical examination; serum TSH assay; and high-resolution, diagnostic ultrasonography. High-resolution ultrasonography enhances thyroid nodule selection and the need for fine needle aspiration selection by sonographically defining size, consistency, and features suggestive of malignancy. Thyroid nodule fine needle aspiration (FNA), especially with ultrasound guidance, enhances the yield of interpretable, nodular-aspirated material for cytologic interpretation by 3–5-fold over simple FNA without ultrasound guidance.