Clinical practice. The thyroid nodule

Ultrasonography for the endocrine surgeon: A valuable clinical tool that enhances diagnostic and therapeutic outcomes

BACKGROUND

Surgeon-performed ultrasonography (U/S) has revolutionized many subspecialties by broadening the diagnostic and interventional scope of practice. We report our experience on the impact of surgeon-performed U/S in an endocrine surgery practice.

METHODS

Prospectively maintained records of patients from November 1999 to November 2004 were reviewed to establish patterns and outcomes of U/S practice. Surgeon-performed neck U/S was done routinely at the initial clinic visit and incorporated into resident/fellow education.

RESULTS

A total of 5703 U/S were performed on endocrine patients with thyroid 42%, parathyroid 57%, and adrenal 1% disorders. Diagnostic fine-needle aspiration biopsy (FNA) was achieved with low sampling errors (<7%). When U/S identified thyroid nodules coexisting with hyperparathyroidism, preoperative FNA correctly established benign thyroid diagnosis and minimized need for thyroidectomy. U/S successfully imaged abnormal parathyroid glands when (99)Tc-sestamibi scans were negative. U/S data significantly changed treatment plans in nearly two thirds of thyroid cancer patients. Surgical residents readily mastered essential U/S skills.

CONCLUSIONS

Surgeon-performed U/S is a highly specific tool for identification of endocrine disease in the neck. It is learned readily and performed accurately, and functions as an informative extension of physical examination. Because it substantially benefits patient care and impacts surgical decision making, neck U/S is recommended highly as a valuable adjunct to endocrine surgical practice.

Early diagnosis and curative therapy of medullary thyroid carcinoma by routine measurement of serum calcitonin in patients with thyroid disorders

To identify patients with medullary thyroid carcinoma (MTC) at a potentially curable stage of the disease, serum concentrations of calcitonin (hCT) were determined in 14,000 patients (including 10,158 patients with thyroid nodules) referred to a thyroid outpatient clinic. Excluding patients in whom elevated basal hCT concentrations had already been known at the time of their referral, 507 patients with thyroid nodules presented basal concentrations of hCT of more than 10 pg/ml. Following stimulation by IV pentagastrin (0.5 microg/kg BW), hCT concentrations of more than 100 pg/ml were seen in 103 patients. This group included 32 new cases of MTC (29 patients with sporadic MTC and 3 new index cases of the familial form) and 43 patients with C cell hyperplasia (CCH). Among the 3,843 patients without thyroid nodules, 2 were found to harbor sporadic MTC while 4 had CCH. As compared to 1.1 cases of MTC per 1,000 patients with nodular thyroid diseases diagnosed in our institution before hCT screening was begun, 3.2 cases of MTC per 1,000 patients were identified when hCT was determined in all patients with thyroid nodules. The determination of hCT in all patients with thyroid nodular disease facilitates the timely diagnosis of MTC, thus providing the chance of curative surgery.

Gray-scale three-dimensional sonography of thyroid nodules: feasibility of the method and preliminary studies

The aim of the study was differential evaluation of new and classical sonographic features of benign thyroid nodules and thyroid cancer with three-dimensional gray-scale sonography and evaluation of the effectiveness of the thin-slice surface rendered images in comparison with multiplanar reformation (MPR) presentation. Fifty-four thyroid nodules were interactively evaluated with thin-slice smooth surface rendering: shape in the c-plane (parallel to the probe) and evaluation of echogenicity, margins and calcification/microcalcification-like echogenic foci in the a-plane (plane of the probe). Evaluation of the level of agreement in readers' interpretation and between sonographic techniques was performed using the kappa statistic. Surface rendering permitted visualization of the shape of the nodule in the c-plane in all cases, in contrast to only up to 48% of cases in MPR evaluation. Lobulated nodule shape in the c-plane was 82-100% sensitive and 47-53% specific in diagnosis of carcinoma. Surface rendered images showed more calcification/microcalcification-like echogenic foci than MPR ones. The level of agreement between the observers in the evaluation of features of thyroid nodules and the agreement between features of thyroid nodules on MPR and surface-rendered images showed at least moderate reproducibility (kappa>or=0.41). Three-dimensional thin-slice surface rendering sonography appears to be a feasible and effective method for thyroid nodule evaluation.

Sonography of Thyroid Nodules

This article describes an approach to some of the commonly encountered, "classic pattern," appearances of both benign and malignant thyroid nodules that are seen in day-to-day practice. These appearances include specific nodules that commonly need fine needle aspiration (FNA)/biopsy, and other nodules that do not usually need FNA/biopsy.

Incidência e mortalidade por câncer de tireóide no Brasil

Esse estudo visou avaliar a incidência e a mortalidade por câncer de tireóide (CT) no Brasil através análise dos dados de sete Registros de Câncer de Base Populacional e do Sistema de Informação sobre Mortalidade. Taxas de mortalidade qüinqüenais por CT, ajustadas para idade, foram calculadas dentro de um período de 20 anos (1980-1999) para o país como um todo. Calculamos taxas trienais de incidência ajustadas por idade empregando os dados disponíveis desde 1993. As taxas de mortalidade ajustadas por idade decaíram de 0,22/100.000 para 0,28/100.000 (-21%) entre os homens, e de 0,42/100.000 para 0,51/100.000 (-17%) entre as mulheres. Entre os homens, as taxas de incidência ajustadas por idade variaram de 0,7/100.000 em Belém até 3,0/100.000 em São Paulo. Essas cidades também apresentaram a mais baixa (0,8/100.000) e a mais alta (10,9/100.000) taxas de incidência ajustada por idade entre as mulheres. A tendência de queda de mortalidade é provavelmente explicada pela melhoria do diagnóstico e do tratamento do CT ao longo do período do estudo, enquanto as variações geográficas da incidência estão provavelmente relacionadas à disponibilidade de recursos de cuidados médicos nas diferentes regiões e na qualidade dos dados dos registros de câncer.

The prognostic value of primary tumor size in papillary and follicular thyroid carcinoma

BACKGROUND

A delay in the diagnosis of differentiated thyroid carcinoma often leads to larger tumors, higher prevalence rates of distant metastasis, and earlier cause-specific deaths. Threshold tumor diameters for extrathyroidal growth, lymph node spread, and distant metastasis in papillary (PTC) and follicular thyroid carcinoma (FTC) remain to be defined.

METHODS

A comparative correlation of primary tumor size and extrathyroidal growth, lymph node spread, and distant metastasis was performed for 500 institutional patients who received surgery for PTC or FTC.

RESULTS

There were 366 patients with PTC (73.2%) and 134 patients with FTC (26.8%). Multifocality (23.5% vs. 9.0%; P < 0.001) and lymph node metastasis (40.2% vs. 19.4%; P < 0.001) were more common in the patients with PTC than in those with FTC. Patients with FTC were older at first diagnosis (51.6 vs. 47.0 years; P = 0.01) compared with the patients with PTC. The FTC tumors were almost twice as large (39.9 vs. 20.6 mm; P < 0.001), and patients had a higher prevalence of distant metastasis (17.9% vs. 6.3%; P < 0.001). When primary tumor diameter was accounted for, cumulative risks of extrathyroidal growth and lymph node metastasis were higher in patients with PTC than in patients with FTC (P < 0.001; log-rank test). In striking contrast, the cumulative risk of distant metastasis was the same for PTC and FTC tumors of equal size (P = 0.89; log-rank test) and increased once the primary tumor size was > 20 mm. Pulmonary metastasis was an earlier event than bone metastasis.

CONCLUSIONS

The data suggested that earlier intervention is warranted to keep suspicious thyroid nodules from growing > 20 mm (or greater than T1) and spreading to distant organs.

[Diagnosis and therapy of thyroid nodules]

Thyroid nodules and goitre can be diagnosed in up to 50% in populations living in iodine deficiency areas. Because of the necessity to exclude malignancy they therefore represent a significant diagnostic and economic problem. Sonography as well as TSH determination are the basic constituents of any thyroid diagnostic work up. Thyroid scintigraphy should be performed with any solitary thyroid nodule >10 mm if the scintigraphic result (together with the sonographic result) is likely to influence the treatment. Except of hot nodules any thyroid nodule should be evaluated by fine needle aspiration biopsy. Because of the lack of controlled studies including sufficient numbers of patients, there is a lack of evidence for some aspects of our everyday clinical practice. The aim of this article is therefore to summarize latest results on pathogenesis, diagnostic tools and recommendations concerning therapy and follow up.

Effect of ultrasound-guided interstitial laser photocoagulation on benign solitary solid cold thyroid nodules - a randomised study

AIM

To evaluate the efficacy of ultrasound (US)-guided interstitial laser photocoagulation (ILP) on thyroid function, nodule size and patient satisfaction in benign solitary solid cold thyroid nodules by comparing one ILP session with no treatment in a prospective randomised study.

MATERIALS AND METHODS

Thirty euthyroid outpatients with a benign solitary solid and a scintigraphically cold thyroid nodule causing local discomfort were assigned to one session of ILP (n = 15) or observation (n = 15) and followed for 6 months. Thyroid nodule volume and total thyroid volume were assessed by US and thyroid function was determined by routine assays before and during follow-up. Pressure and cosmetic complaints before and at 6 months were evaluated on a visual analogue scale. ILP was performed under US guidance and with an output power of 2.5-3.5 W.

RESULTS

In the ILP group, the nodule volume decreased from 8.2 ml (6.1; 11.9) (median; quartiles) to 4.8 ml (3.0; 6.6) after 6 months (P = 0.001). The overall median reduction was 44% (37; 52), which correlated with a significant decrease in pressure symptoms as well as cosmetic complaints. In the control group, a non-significant increase in median nodule volume of 7% (0; 34) after 6 months was seen. No major side-effects were seen in the ILP group. There was no correlation between thermal energy deposition and nodule volume reduction. Thyroid function was unaltered throughout.

CONCLUSION

US-guided ILP, given as a single treatment, resulted in a satisfactory clinical response in the majority of patients with a benign solitary solid cold thyroid nodule, and may become a clinically relevant alternative to surgery in selected patients.