(1/445) A new rapid technique for the fixation of thyroid gland surgical specimens.
One of the main diagnostic problems in thyroid pathology is to distinguish between follicular adenoma and follicular carcinoma. Thorough sampling of the nodule's capsule is recommended in order to identify capsular invasion. However, during the hardening of the tissue, by the usual fixatives the capsule shrinks and rolls downwards and sometimes the capsule separates from the remaining tissue. The present work evaluates the use of "Lymph Node Revealing Solution" (LNRS) for the rapid fixation (2h) of different thyroid lesions as compared to that of formalin. Fifty-one unselected consecutive cases of thyroid nodules, which included various benign and malignant lesions, were examined. Each specimen was cut in two equal parts; one was fixed in LNRS, the other in formalin. Fixation in LNRS for 2 hours gave adequate results in sectioning and staining of the tissue, and excellent immunostains. Its advantage over formalin is the conservation of the natural relationship between the capsule and the rest of the tissue, on the same plane, as well as the short time required for the final diagnosis. (+info)
(2/445) Evaluation of "solitary" thyroid nodules in a community practice: a managed care approach.
Evaluation of thyroid nodules remains a challenge for primary care physicians. To include or exclude the presence of malignancy in a thyroid nodule, radioisotope scan, ultrasound, and fine-needle aspiration biopsy of the thyroid generally are used. The objectives of this study were to determine the utility and cost effectiveness of fine-needle aspiration biopsy of solitary thyroid nodules in a community setting; to compare the cost of fine-needle aspiration biopsy with that of radioisotope scan and ultrasound; and to determine whether the practice of obtaining radioisotope scans and ultrasound has changed in the 1990s compared with the 1980s. Patients were referred by community physicians to university-based endocrinologists for evaluation of thyroid nodules. Many of the patients had previously undergone radioisotope scans and ultrasound scans at the discretion of their primary care physicians. All patients underwent fine-needle aspiration biopsy. The biopsy results were evaluated prospectively, and the practice of community physicians' obtaining radioisotope scans and ultrasound scans was compared for the 1980s and 1990s. Eighty-three patients underwent 104 biopsies. In 20 biopsies the specimens were inadequate; the others showed 70 benign, 9 suspicious, and 4 malignant lesions. All four patients with biopsy findings read as malignant were found to have malignant growth at surgical procedures. Two benign biopsy findings were false-negative results. Malignant growth was correctly diagnosed later for one patient at a second biopsy and for the other because of growth of the nodule. The cost of 104 biopsies was $20,800. The cost of radioisotope scans was $22,400, and the cost of ultrasound scans was $10,640. The frequency of obtaining radioisotope scans (84.5% vs 77%) and ultrasound scans (65% vs 45%) was slightly higher in the 1990s compared with the 1980s. Fine-needle aspiration biopsy is a safe and cost effective initial evaluation modality for smaller community-based centers, as it is at large tertiary centers. The cost incurred ($33,040) in obtaining the radioisotope scans and ultrasound scans could have been saved if fine-needle aspiration biopsy had been used as the initial diagnostic procedure for evaluation of these nodules. Although radioisotope scan and ultrasound scan are of little diagnostic help in the evaluation of thyroid nodules, they continued to be obtained at a high frequency during the last decade. (+info)
(3/445) De Quervain's subacute thyroiditis presenting as a painless solitary thyroid nodule.
We describe a 39-year-old woman presenting with a painless solitary thyroid nodule, initially without signs suggesting thyroiditis. The serum level of thyrotropin was suppressed whereas those of thyroxine and triiodothyronine were normal. Fine needle aspiration cytology showed no signs of inflammation or malignancy. One week later, the patient felt pain and tenderness on her neck, and erythrocyte sedimentation rate and C-reactive protein were markedly elevated. Thyroid scintigraphy showed a suppressed thyroid pertechnetate uptake. At that time, the diagnosis of subacute thyroiditis was made. Upon treatment with steroids the patient's symptoms as well as the thyroid nodule resolved. This case illustrates that subacute thyroiditis de Quervain may present as a solitary, painless nodule with suppressed thyrotropin and should therefore be considered in the differential diagnosis of such lesions. (+info)
(4/445) Management of differentiated thyroid cancer diagnosed during pregnancy.
OBJECTIVE: To assess the outcome of thyroid cancer diagnosed during pregnancy. DESIGN: Retrospective analysis of patients diagnosed between 1949 and 1997 with thyroid cancer presenting during pregnancy. RESULTS: Nine women with a median age of 28 years were identified. A thyroid nodule was discovered by the clinician during routine antenatal examination in four cases, the remainder had noted a lump in the neck. In all patients, the nodule was reported to almost double in size during the pregnancy. One patient underwent subtotal thyroidectomy during the second trimester; eight were operated on within 3 to 10 months from delivery. Total thyroidectomy was performed in five and subtotal thyroidectomy in four. All tumours were well differentiated and ranged in size from 1 to 6 cm. OUTCOME: The median follow-up was 14 years (5-31 years). One patient relapsed locally requiring further surgery. One patient developed bone metastases dying 7 years after presentation; her planned treatment had been delayed because of an intervening pregnancy. Eight of the original cohort of patients are currently disease free. CONCLUSIONS: Differentiated thyroid cancer presenting in pregnancy generally has an excellent prognosis. When the disease is discovered early in pregnancy, surgery should be considered in the second trimester but radioiodine scans and treatment can be safely delayed until after delivery. In all cases, treatment should not be delayed for more than a year. (+info)
(5/445) Thyroid nodular disease after radiotherapy to the neck for childhood Hodgkin's disease.
Patients who receive radiotherapy to the neck are at risk of developing thyroid dysfunction. This prospective study of patients whose treatment for Hodgkin's disease in childhood included radiotherapy to the neck aimed to investigate the incidence and natural history of thyroid dysfunction and the morphological changes of the gland demonstrated on ultrasound. Forty-seven patients were investigated by clinical examination, thyroid function tests and thyroid ultrasound. Only six patients had a clinically detectable abnormality, but 64% had abnormal thyroid function tests. All patients had an abnormal thyroid ultrasound scan and 42% had at least one focal abnormality. A significant association was found between the presence of a focal lesion on ultrasound and young age at radiotherapy, longer follow-up and the length of time that the thyroid-stimulating hormone (TSH) level had been elevated. During follow-up, 65% of patients not on thyroxine developed new focal abnormalities. The longest time interval between radiotherapy and an increase in TSH level was 94 months, and from radiotherapy to the appearance of a focal abnormality on thyroid ultrasound was over 18 years. Three patients were found to have a thyroid carcinoma. These findings indicate the importance of long-term follow-up for patients treated by neck irradiation for Hodgkin's disease in childhood. (+info)
(6/445) Human telomerase reverse transcriptase (hTERT) gene expression in thyroid neoplasms.
Ten percent of fine-needle aspirations (FNAs) of the thyroid are deemed "indeterminate" or "suspicious" for malignancy by the cytopathologist, but most of these lesions are benign. Therefore, additional markers of malignancy may prove to be a useful adjunct. The catalytic component of telomerase, human telomerase reverse transcriptase (hTERT), has been found to be reactivated in immortalized cell lines. Reverse transcription-PCR of the hTERT gene revealed expression in 15 (79%) of 19 malignant thyroid neoplasms, including 6 of 6 follicular carcinomas and 9 of 13 papillary carcinomas. In contrast, hTERT gene expression was detected in only 5 (28%) of 18 benign thyroid nodules, including 2 of 7 follicular adenomas and 3 of 11 hyperplastic nodules. All five benign thyroids exhibiting hTERT gene expression had lymphocytic thyroiditis. No normal thyroids exhibited hTERT gene expression. Telomerase enzyme activity was examined in all 37 nodules and was found to correlate with hTERT gene expression in 35 (95%) nodules. The two cases in which telomerase activity and hTERT expression results were discrepant were in two papillary carcinomas that were telomerase activity negative and hTERT positive. Finally, we have demonstrated that hTERT gene expression can be measured in in vivo FNA samples. These results suggest that hTERT expression may be more accurate than telomerase activity in distinguishing benign from malignant and may be measured in FNA samples from suspicious thyroid lesions. (+info)
(7/445) Incidental detection of familial medullary thyroid carcinoma by calcitonin screening for nodular thyroid disease.
Serum calcitonin screening has recently been found to be a useful supplement to fine-needle aspiration biopsy, ultrasound and radionuclide imaging in the evaluation of thyroid nodules. We describe a case where introduction of routine calcitonin screening in nodular thyroid disease led to the detection of a family with medullary thyroid carcinoma. The benefits and problems of basal and stimulated serum calcitonin testing and ret-proto-oncogene mutation studies are exemplified and we discuss the appropriate use and interpretation of these tests. We conclude that routine basal serum calcitonin measurement in nodular thyroid disease and thoughtful use of ret-mutation analysis is cost-effective in detecting medullary thyroid carcinoma and multiple endocrine neoplasia type II. (+info)
(8/445) Thyroid nodules, thyroid function and dietary iodine in the Marshall islands.
BACKGROUND: Thyroid nodules have been found to be common in the population of the Marshall Islands. This has been attributed to potential exposure of radioiodines from the nuclear weapons tests on Bikini and Eniwetok between 1946 and 1958. METHODS: In order to get a full picture of thyroid pathology in the Marshallese population potentially exposed to radioactive fallout we performed a large thyroid screening programme using palpation, high resolution ultrasound and fine needle biopsies of palpable nodules. In addition, various parameters of thyroid function (free T3, free T4, thyroid stimulating hormone [TSH]) and anti-thyroid antibodies were examined in large proportions of the total population at risk. Since dietary iodine deficiency is an established risk factor for thyroid nodules, iodine concentration in urine samples of 362 adults and 119 children was measured as well as the iodine content of selected staple food products. RESULTS: The expected high prevalence of thyroid nodules was confirmed. There was no indication of an increased rate of impaired thyroid function in the Marshallese population. A moderate degree of iodine deficiency was found which may be responsible for some of the increased prevalence of thyroid nodules in the Marshallese population. CONCLUSIONS: Studies on the relationship between exposure to radioiodines and thyroid nodules need to take dietary iodine deficiency into account in the interpretation of findings. (+info)