Clinical differentiation between thyroid cancer and benign goiter; an evaluation

Clinical Examination and 131Cs Scanning in the Diagnosis of Cold Nodules of the Thyroid

The usefulness of 131Cs scanning in preoperative diagnosis of 131I cold nodules of the thyroid that present no clear clinical sign of malignancy is discussed. The results of clinical examination of 283 thyroid nodules, associated in 139 cases with 131Cs scanning, are correlated with the histologic nature. In nodules that were classified as cold, warm or hot in the 131Cs scan, the incidence of malignancy was 2.6, 12.3 and 25 %, respectively. In the nodules that, on the basis of clinical examination, were classified as probably benign, dubious or suspected for malignancy, the incidence of cancer was, respectively, 3.6, 26.3 and 72.7 %. Malignancy ocurred in 16 of 144 patients that were selected for surgical treatment only on the basis of clinical data and in 17 of 139 patients that were selected on the basis of clinical examination associated with 131Cs scanning. The accuracy of clinical preoperative diagnosis of thyroid cold nodules does not seem to be significantly improved by association of 131Cs scanning.

Fine-needle Aspiration Biopsy of the Thyroid

Fine-needle aspiration biopsy is of primary importance in the screening of thyroid nodules. This report summarizes the results of a 7-year personal experience, compre hensive of 1,936 biopsies from 1,881 patients with single or multiple nodules. Ade quate material was obtained in 1,862 cases (96.2%) and interpreted as "negative," "suspicious," or "positive" for malignancy. Histological assessment in 311 operated cases revealed 6 false negatives and 3 false positives. The sensitivity, specificity, and accuracy of the test were 88.0%, 98.4%, and 96.2%, respectively. The predictive value was also high. These findings offer further evidence of the reliability of fine-needle aspiration biopsy in the evaluation of thyroid nodules, especially when the procedure is performed by experienced operators and close cooperation between clinicians and pathologists is established. Int J Surg Pathol 1 (3):171-176, 1994

Fine-needle aspiration biopsy of the thyroid

The routine use of thyroid FNAB caused profound changes in the management of thyroid nodules. FNAB allows a prompt identification and treatment of thyroid malignancies and avoids unnecessary surgery in patients with benign lesions, improving quality of life in patients with thyroid nodules. Furthermore, FNAB provides guidance for the type of surgery and reduces costs of care. On average, standard FNAB is nondiagnostic in 25% to 40% of cases, which include inadequate specimens and indeterminate (suspicious) diagnoses. In addition, a small percentage of false-negative diagnoses occur, which are unavoidable and raise concern of a late diagnosis of cancer. To minimize the limitations of FNAB, every center should reach and maintain a high standard of expertise in all of the steps of smear preparation and interpretation. Alternative modes of sampling or sample preparation may result in a reduction of nondiagnostic samples and better accuracy. Every center should set up clinical guidelines tailored to their own FNAB results and including the evaluation of clinical data. More work is needed to increase the accuracy of FNAB in suspicious cases. Toward this goal a variety of molecular markers have been evaluated; although none of them are ideal, some are promising. More studies need to be carried out in larger series to further evaluate the accuracy of these markers in identifying specific cancer histotypes within the group of suspicious lesions. It is hoped that, in the near future, the routine use of a combination of these markers will cost-effectively improve the diagnosis of malignant nodules classified as suspicious on traditional cytology. Statistical methods such as bayesian analysis or neural networks can be advantageously used to integrate different relevant information derived from family and personal history, clinical data, cytologic results, and evaluation of molecular markers.

Clinical features associated with an increased risk of thyroid malignancy in patients with follicular neoplasia by fine-needle aspiration

The application of fine-needle aspiration (FNA) to the evaluation of the thyroid nodule has greatly enhanced the ability of the clinician to appropriately select patients for thyroidectomy. However, despite extensive experience with thyroid FNA, the cytological distinction of benign from malignant follicular neoplasia remains problematic. As a result, most patients with FNA findings of a follicular neoplasm are referred for thyroidectomy. The goal of the present study was to develop clinical criteria capable of predicting malignancy in patients with an FNA diagnosis of follicular neoplasm. Among 1121 patients undergoing thyroid FNA at two large teaching centers during the period 1990 to 1995, 149 patients had cytological findings consistent with a follicular neoplasm. Among 103 patients referred for thyroidectomy, 22 (21%) were found to have a malignancy in the biopsied nodule. Among patients subjected to thyroidectomy, the risk of malignancy was significantly higher when follicular neoplasia was present in a male (43% vs. 16% for females, p = 0.007), when the nodule was greater than 4 cm to palpation (40% vs. 13% for nodules less than 4 cm, p = 0.03), or when the nodule was judged to be solitary by palpation (25% vs. 6% for a dominant nodule in a multinodular goiter, p = 0.02). Bayesian analysis of the data reveals that after an FNA showing a follicular neoplasm, the risk of malignancy in males with large nodules was nearly 80%, compared with a rate of only 3% in females with small nodules. These results suggest that clinical features including gender, nodule size, and character of the gland by palpation can be systematically integrated into the decision analysis, thereby improving the selection of patients for surgical referral.

Comparison of membrane proteins from benign and malignant human thyroid tissues by two-dimensional polyacrylamide gel electrophoresis

In this study two-dimensional (2D) polyacrylamide gel electrophoresis with silver staining was used to analyze cellular membranous proteins of various normal and pathological human thyroid tissues. The aim was to understand the differences in cellular membranous proteins between these tissues, which would aid in the differential diagnosis of thyroid malignancy. Characteristic protein spots had a molecular mass of 50-64 kDa and a pI of 5.7-6.5. There were two groups of isoform protein spots in this area. The higher-molecular-mass group was found in follicular thyroid cancer tissues which and was not visible in normal thyroid tissues. The low-molecular-mass group was found in follicular carcinoma or adenoma tissues and was detected in one to three spots. The papillary thyroid carcinoma tissues gave different 2D gel maps. There were few spots of papillary thyroid carcinoma tissue membranous proteins within the examined area. The 2D gel maps may be used for differential diagnosis of follicular neoplasm. The characteristics of these protein spots require further investigation.

Relationship between vocal cord paralysis and benign thyroid disease

BACKGROUND

Vocal cord paralysis is generally associated with advanced thyroid malignancy. It may also be present in the setting of benign thyroid disease. This association may be incidental as well as causal.

METHODS

Retrospective review of cases with concurrent diagnosis of vocal cord paralysis and benign thyroid disease.

RESULTS

Eight cases found, all with documented vocal cord paralysis, by laryngoscopy. Four patients had nodular thyroid disease, but in two it was contralateral to the recurrent laryngeal nerve paralysis. The remaining patients had goiters of various sizes. Six patients were euthyroid, two on thyroid hormone replacement. Two patients were thyrotoxic: one had Graves' disease and the other had subacute thyroiditis.

CONCLUSIONS

Vocal cord paralysis can be the result of benign thyroid disease by such mechanisms as compression, stretching, or inflammation. Malignant thyroid disease should always be ruled out in structural thyroid abnormalities. Vocal cord paralysis can also be an incidental finding unrelated to thyroid abnormality.

Preoperative diagnostic tests for operable thyroid disease

Although the availability and acceptance of fine-needle aspiration biopsy (FNAB) of thyroid nodules has increased, many physicians still use thyroid scintigraphy for distinguishing benign from malignant lesions. We evaluated these diagnostic tests in 350 patients who had thyroid surgery in our institution between 1977 and 1990. Histologic confirmation of FNAB was obtained in 265 patients. In the group of patients having surgery, 247 thyroid scintigraphies were performed. Our patients were divided into two groups (1977-1986 and 1986-1990). The first group comprised 173 patients with 173 FNABs and 126 scintigrams. The second group consisted of 177 patients having 92 FNABs and 121 scintigrams. Results of scintigrams were analyzed in the second group only. In 5 out of 120 cases where the FNAB result was "benign or probably benign" the lesion appeared to be malignant postoperatively. If the FNAB result was "malignant or probably malignant" (n = 83) the pathology report confirmed a malignancy in 68 cases (81.9%). In 56 instances of all 265 FNABs the cytology report was not conclusive ("uncertain"); in 21.4% of these cases a malignancy was found postoperatively. An FNAB-result "(probably) malignant" had a positive predictive value of 0.819 while the negative predictive value of a result "(probably) benign" is 0.950. An "uncertain" result does not take away our concern so this result should have the same consequences as those of a result "(probably) malignant". In that case, FNAB-sensitivity is 93.0% and specificity 66.1%. Eighty-five of the last 116 scintigraphies showed a solitary node. Eleven of these nodes were hot while 74 were cold.(ABSTRACT TRUNCATED AT 250 WORDS)

Cancer risk in patients with cold thyroid nodules: relevance of iodine intake, sex, age, and multinodularity

PURPOSE

We evaluated the frequency of thyroid cancer in patients with cold thyroid nodules in relation to iodine intake, sex, age, and multinodularity in a consecutive series of patients with nodular thyroid diseases.

PATIENTS

In the period from 1980 to 1990, 5,637 patients were studied: 4,176 patients were from an iodine-sufficient area (ISA) and 1,461 from an adjacent iodine-deficient area (IDA). Surgery was performed in 792 patients on the basis of a suspicious or malignant finding at fine-needle aspiration biopsy.

RESULTS

The overall thyroid cancer frequency was 4.6% (259 patients had cancer). Iodine intake affected the cancer rate in patients with cold nodules. The frequency of cancer in patients with cold thyroid nodules was 5.3% in the ISA and 2.7% in the IDA. This difference, however, was significant only in females. Sex had a major influence on the malignant rate of cold nodules; although female patients were more frequently observed (n = 5,028) than male patients (n = 609), the frequency of cancer was significantly lower in female patients with cold nodules (4.2%) than in males (8.2%). Age was an important factor in both sexes. The proportion of nodules that were malignant was smallest in patients of the 4th decade and was greatest in patients younger than 30 years or older than 60 years. Multivariate analysis showed that sex and age interact in determining the cancer risk in patients with thyroid nodules. Finally, the frequency of thyroid cancer in patients with a solitary nodule was not different from the frequency in patients with multiple nodules.

CONCLUSION

Our study indicates that thyroid cancer risk in a patient with a nodular goiter varies markedly according to iodine intake, sex, and age but not in relation to multinodularity, as assessed by clinical examination. The knowledge of these epidemiologic aspects of thyroid cancer may increase the accuracy of the preoperative selection of patients with cold nodules of the thyroid.

Evaluation of the fine needle aspiration biopsy in the preoperative selection of cold thyroid nodules

From 1980 to 1988 the authors examined by fine needle aspiration biopsy (FNAB) 4609 patients with solitary thyroid nodules or multinodular goiters. A total of 5605 "cold" thyroid nodules were evaluated and classified, on the basis of the cytologic findings, as malignant, follicular lesions (probably malignant and probably benign) and benign. Then the authors compared the preoperative cytologic findings with the postoperative histologic results in 827 nodules from patients who underwent surgery. In the 805 thyroid nodules in which an adequate cytologic specimen was obtained, false-negative results were 2.3% and false-positive findings were 1.1% By comparing cytologic and histologic diagnoses, preoperative FNAB resulted in the ability to accurately assess the risk of cancer in a thyroid nodule; since 250 nodules were identified as malignant, the risk of a "cold" thyroid nodule being cancer was 4.46% in this series.

Management of the thyroid nodule

The approach to the patient with a palpable solitary thyroid nodule remains controversial. In the rare patient with signs and symptoms suggestive of malignancy, the course of action is reasonably established. However, the patient with an asymptomatic solitary thyroid nodule presents a dilemma. The therapeutic alternatives range from suppressive medical therapy with serial examinations to surgical excision; therefore, to obviate unnecessary surgery, several diagnostic techniques and approaches have evolved which attempt to predict the presence of malignancy. A multitude of articles reflects the widespread disagreement among physicians regarding these diagnostic approaches. Thus, many questions still remain as to the proper management of patients with solitary nodules. The issue is further confounded by problems in assimilating and practically applying the results of the various studies, which often differ in their results. In this report, data regarding the prevalence of the solitary thyroid nodule are reviewed, and the clinical significance of the solitary thyroid nodule is discussed. The problem of management is examined in terms of the various diagnostic approaches to the solitary thyroid nodule: history and physical examination, laboratory tests, ultrasonography, thyroid suppressive therapy, scanning techniques, and fine-needle aspiration. The efficacy of each technique is critically evaluated with an emphasis upon the ability to distinguish benign from malignant disease. The overall aim of this report is to establish a reasonable diagnostic approach to the asymptomatic patient with the solitary palpable thyroid nodule, based upon a critical review of the literature.

The solitary thyroid nodule: diagnosis and management of malignant disease

While few solitary thyroid nodules are carcinomatous, it is essential to identify and preferentially select those that are for surgery. Clinical, biochemical, serologic, radiographic, scintigraphic, sonographic, biopsy, and even therapeutic evaluation may be necessary to choose those patients with the greatest probability of malignancy. The benefits and limitations of each diagnostic modality are discussed, and the importance of fine-needle aspiration is stressed. After the operative confirmation of malignancy, the prognosis in any given case depends on 1) the histologic type of the neoplasm, 2) its size and extent, 3) the presence of angioinvasiveness, 4) the tendency toward multicentricity of the lesion, 5) the age and sex of the patient, and 6) whether distant metastases are present. These factors influence the extent of surgery required for well-differentiated carcinomas. Meticulous dissection and preservation of the recurrent laryngeal nerves and the parathyroid glands along with their blood supply are important if total thyroidectomy for papillary carcinoma is to be employed with an acceptable operative morbidity to optimize survival. The value of the adjunctive use of thyroid hormone and radioactive iodine is also discussed. Finally, the clinical behaviors and treatments of undifferentiated carcinomas, sarcomas, lymphomas, and neoplasms metastatic to the thyroid gland are reviewed.

Management of thyroid nodules. II: Scanning techniques, thyroid suppressive therapy, and fine needle aspiration

For the differentiation of benign from malignant thyroidal disease, ultrasound displays anatomic but not histologic features. Other visualization techniques can be used including isotope scanning (radioiodine, 99m technetium, 241 americium fluorescence, 131 cesium, 67 gallium, 75 selenomethionine, 201 thallium, 32 phosphorus, 99m Tc-bleomycin, 197 mercury, 133 xenon), thermography, x-ray techniques (plain films, computed tomographic scan, xeroradiography, chest x-ray barium swallow, lymphography, angiography), and thyroid hormone suppression. Needle biopsy can be done by core biopsy (Vim-Silverman and drill biopsy), large needle biopsy for histologic processing and fine needle aspiration for cytologic interpretation. The latter is the safest, most reliable, and most cost-effective technique currently available to differentiate between benign and malignant thyroidal disease and has great promise for the future.

Management of thyroid nodules. I: History and physical examination, blood tests, X-ray tests, and ultrasonography

The approach to the management of the thyroid nodule remains controversial. Confusion exists because virtually any thyroidal disease can present as a clinically solitary nodule which means there is no uniformity regarding natural history, incidence, prevalence, epidemiology, and pathophysiology.. The variety of definitions of thyroid nodules and thyroid carcinoma and the different modes of study selection and individual bias add to the confusion. Diagnostic approaches have not yielded a completely reliable technique to differentiate benign from malignant thyroidal disease. A history of neck irradiation of cervical lymphadenopathy significantly increases the chance of thyroid malignancy, but other parameters of the history or physical examination as well as blood tests are unreliable. Ultrasound displays anatomic but not histologic features. X-ray techniques (plain films, computed tomographic scans, xeroradiography, chest x-ray, barium swallow, lymphography, and angiography) have been used to visualize thyroid nodules, with some techniques proving more useful than others.

Early diagnosis and detection of clinically non-suspected thyroid neoplasia by the cytologic method: a critical review of 1536 aspiration biopsies

Aspiration biopsies were performed on 1536 patients with goiter who showed scintigraphically "cold" nodules. Twelve among them had clinical and cytological positive diagnosis. The remaining 1524 patients had aspiration biopsies without suspicion of the malignant nature of their goiters. Among them, 45 patients had a positive or suspect cytological diagnosis. Fourteen had not been yet operated on. Thirty-one were operated on and 28 malignancies were confirmed histologically. In three patients, cytological diagnosis was false positive. The remaining patients were cytologically negative. Thirty-seven were operated on and four false negative cases were found. The application of aspiration biopsy on every patient with a cold thyroid nodule resulted in the detection and very early diagnosis of clinically unsuspected thyroid neoplasms, the great majority of which were confined to the gland itself without metastasic spread. This fact makes the prognosis better. In addition, it is probable that the early detection of differentiated thyroid neoplasms and their surgical ablation interrupt their natural course towards anaplastic carcinoma, with its grim prognosis.

Management of thyroid nodules in the elderly

Eleven malignant thyroid tumors were found in 100 consecutive patients more than sixty years old having thyroid operations. Based on preoperative findings, these 100 patients could be separated into two groups according to high and low risk for malignancy. Clinical manifestations in the high risk group were presence of a discrete cold thyroid nodule, hoarseness, dysphagia, an enlarging mass, or palpable ipsilateral cervical adenopathy; and in the low risk group, asymptomatic multinodular goiter, diffusely enlarged glands with elevated antithyroid antibody titers, and a family history of goiter. All eleven patients with malignant thyroid tumors were found in the sixty-six patients considered at high risk, whereas no malignant lesions were found in the low risk patients. Six of the malignant thyroid tumors were undifferentiated and in three of these a thyroid nodule had been present for more than fifteen years. There were no operative deaths and only one significant complication, a recurrent laryngeal nerve injury. Thyroidectomy is indicated for elderly patients with thyroid nudules who have features of the high risk group, whereas patients in the low risk group can be safely followed.

The single palpable thyroid nodule: evaluation by 99mTc-pertechnetate imaging

The role of 99mTc-pertechnetate thyroid imaging in the preoperative assessment of patients with single palpable thyroid nodules was evaluated. The frequency of cancer in hypofunctional nodules was similar to that found in previous studies with 131I. The 99mTc-pertechnetate image allowed a reliable separation of pathologically uninodular thyroids from those that were multinodular, and demonstrated multiple thyroid lesions that had not been detected by physical examination in over one-third of the cases. The frequency of cancer in thyroids containing a solitary or dominant hypofunctional nodule was higher (17%) than that in thyroids with a multinodular scan appearance (less than 5%).

Papillary thyroid carcinoma in Denmark, 1943--1968

The material presented dates from a nationwide Cancer Registry, and covers all cases of papillary thyroid carcinoma (T.C.) diagnosed in Denmark from 1943 to 1968, including those based on postmortem examinations. Direct comparison with clinical data from hospitals elsewhere will therefore tend to show less favorable results. In general, Danish cases show a higher average age than those from American hospitals. For the younger age groups this may to some extent be explained by the fact that therapeutic x-irradiation of the thymus during childhood has never been practiced in Denmark. However, the later occurrence in life of Danish cases and the less favorable prognosis might suggest a failure to realize the malignant character of the lesion in the earlier part of its course, and a variable experience on the part of the surgeons and the variety of institutions from which the material was collected. The age-adjusted incidence rate, the mortality, and complications are discussed. It is concluded that the prognosis may be improved considerably by more extensive operations on the thyroid gland, avoiding complications such as paralysis of the recurrent laryngeal nerve and tetany. The surgical efforts should be supplemented with suppression of the TSH production. In the present retrospective study it was not possible to report 20- and 30-year survival rates. This is a task for the future, as is the planning of prospective studies which, in the case of a disease as rare as papillary T.C., should be established on an international basis.

Thyroid cancer: twenty years' experience in a general hospital

Twenty year's experience of thyroid cancer in a district general hospital has been reviewed. Its incidence, prognosis and natural history have been studied. Particular attention has been focused on the relationship of malignant to benign goitre. The relevance of this to the treatment of 'apparently benign goitre' is discussed. Clinical evidence is presented supporting the hypothesis that differentiated thyroid carcinoma evolves from a solitary focus through a multinodular form before presenting the picture of a frankly malignant locally invasive cancer. An increase in the incidence of papillary carcinoma is confirmed.

Clinical diagnosis of thyroid cancer

In a survey of 293 patients with carcinoma of the thyroid, a goitre or enlarged lymph nodes in the neck were the commonest symptoms and a mass confined to one lobe the commonest sign. Hardness of the mass was an important diagnostic feature, and at least two-thirds of the tumour could be recognized before operation. It is suggested that the preoperative evaluation of thyroid swellings should be classified as benign, cancer suspected, and cancer probable.