Hürthle cell tumor dwelling in hot thyroid nodules: preoperative detection with technetium-99m-MIBI dual-phase scintigraphy

Single injection dual-phase scintigraphy (early and late acquisitions) with 99mTc-MIBI was used to differentiate benign and malignant hot thyroid nodules. METHODS: Thirteen euthyroid and two hyperthyroid patients displaying a hot thyroid nodule on the 99mTc scan due to an autonomously functioning thyroid nodule (AFTN) underwent early (15-30 min) and late (3-4 hr) thyroid scintigraphy after the administration of 740-1000 MBq 99mTc-MIBI. Visual scoring was done to assess nodular tracer uptake and retention. In addition, the nodular-to-thyroid (N/T) uptake ratio in the early and late image and the washout rates (WO) from the nodule and thyroidal tissue were measured. All patients underwent thyroid surgery. RESULTS: Histopathology revealed a Hürthle cell tumor in three nodules, a benign adenoma with oxyphilic metaplasia in two nodules and a benign adenoma without oxyphilic cells in the remaining 10 nodules. The Hürthle cell tumor nodules displayed intense and persistent uptake of 99mTc-MIBI (N/T was 2.81 +/- 0.52 and 5.53 +/- 1.06 in early and late images, respectively; WO from the nodule was 12.33 +/- 0.47, WO from the thyroidal tissue was 22.00 +/- 3.56). The benign nodules showed intense uptake in the early image and intense uptake to absent retention in the late image (N/T was 2.94 +/- 1.31 and 1.62 +/- 0.50 in the early and late images, respectively; WO from the nodule was 20.25 +/- 2.92, WO from the thyroidal tissue was 20.33 +/- 2.92). CONCLUSION: Single injection dual-phase 99mTc-MIBI scintigraphy of the thyroid with AFTN can identify nodules as a result of the activity of a Hürthle cell tumor, since these tumors cause intense and persistent tracer uptake in contrast with a benign AFTN.     

Levothyroxine suppressive therapy for solitary thyroid nodule

In order to evaluate the efficacy of a TSH suppressive dose of levothyroxine to reduce the volume of a single thyroid nodule we studied 55 euthyroid patient: 45 (group A) were suppressed with LT4 (mean 1.7 +/- 0.9 micrograms/Kg/day) for 21.3 +/- 5.3 months, and 10 patients (group B) served as controls. All the nodules were "cold" at scintiscanning, solid at ultrasonography and benign by fine-needle aspiration cytology. As responders were assumed the nodules shrinked at the end of treatment of 50% in volume. Thyroid function values (TSH, T4, FT4, T3, FT3, thyroid peroxidase and thyroglobulin antibodies), clinical and ultrasonographic findings were evaluated initially and at the end of the study. A significant nodular volume decrease occurred in 8 treated patients (17.8%) while 37 (82.2%) amongst the group suppressed and all controls showed no change (A vs B = NS). In two untreated patients new nodules were noted; no new nodules were discovered in the treated group (A vs B p < 005). No side effects occurred in any treated patient, even if at the end of treatment a significant T4 and FT4 (p < 0.01) increase was observed. No one onset parameter can predict the response to the therapy. These results suggest that only a small group of patients affected by a single thyroid nodule seems to respond to a TSH suppressive therapy.     

Training for Iowa physicians

"Autonomous" thyroid nodule is a localized nodular lesion of the thyroid gland characterized by growth, iodine uptake and function, all independent from TSH control. These nodules represent a heterogeneous anatomic and clinical entity. The clinical diagnosis is based upon a negative suppression of nodule iodine uptake and scan imaging by T3 administration. The nodule function is determined by high serum thyroid hormone levels and/or low TSH (measured by ultrasensitive assay). Etiology and pathogenesis of these nodules is not yet completely clarified. Both genetic and environmental factors determine nodule growth and function: thyroid cells, in fact, are genetically heterogeneous and may have intrinsic (congenital) characteristics that may promote the growth of cellular clones having mitotic and functional activity that is partially independent of TSH. In these particular cell clones, environmental factors like iodine deficiency or other goitrogens may favour the growth of autonomous nodules and also, by activating their function, may induce toxicity. The autonomous thyroid nodules need to be treated only when they become toxic: in this case both surgical excision or radioiodine may be used.     

Role of high-resolution pinhole tomography in the evaluation of thyroid abnormalities

The present study was undertaken to evaluate the contribution of pinhole-single photon emission computed tomography (P-SPECT) to scintigraphy of the thyroid gland. Thirty-six patients, referred for thyroid scintigraphy because of palpatory or ultrasonographic findings, were studied after intravenous administration of technetium-99m pertechnetate (222 MBq) using a rectilinear scanner and a single-headed rotating gamma camera equipped with a pinhole collimator. P-SPECT study was acquired on a 128 x 128 matrix, in 30 projections over 180 degrees and an acquisition time of 40 seconds per step. After transaxial reconstruction, coronal slices were compared with planar views obtained by the scanner. The size of the thyroid gland obtained by P-SPECT matched the life-size image of a rectilinear scan, and it clearly delineated the shape and borders of two huge multinodular glands. Its major contribution was in its improved resolution. Pinhole-SPECT identified 21 foci not visualized on planar views, 19 cold lesions, and 2 "warm" nodules embedded in normal tissue of 13 patients. Furthermore, it clearly delineated 18 discrete ill-defined nodules of 13 patients, (single in 4 patients and multiple in 9 patients): 16 cold lesions, and 2 hot foci. When a distinct palpable nodule was present, whether cold (22 lesions) or hot (2 foci), SPECT was of no additional diagnostic value. However, when the palpable nodule was a toxic one, the contralateral suppressed lobe was visible on SPECT only. Two ultrasonographic findings, of 3- and 5-mm in diameter, were neither identified on planar views nor on P-SPECT. In conclusion, P-SPECT of the thyroid gland improves delineation of huge multinodular glands and detection of small nodules (within the resolution of the camera) that could otherwise have been overlooked on planar views of a thyroid scanner. It allows for definition of tracer uptake in tiny discrete nodules and in multinodular goiter, and is a better guide to the physician in fine-needle aspiration of the cold areas.     

Scintigraphic discordances between technetium 99m and iodine 131 in the study of thyroid nodules

Eighty thyroid nodules found to be hyperfixating, isofixating or heterogeneous after an initial scintigraphy with Technetium 99m were studied comparatively using iodine 131. Differences in the apparent activity of the nodule and the extra-nodular parenchyma were found in one third of cases. A "cold nodule" appearance, not seen with techneitum was found in 8 cases at the time of the examination using iodine. Five of these patients underwent operation, the diagnosis being a carcinoma in one.     

Refined use of scintigraphy in the evaluation of nodular thyroid disease

BACKGROUND: Scintigraphy has been advocated in patients with a thyroid nodule when fine needle aspiration biopsy (FNAB) is not definitive. The purpose of this study was to determine the incidence of hyperfunctioning nodules in patients without a definitive FNAB, the correlation of serum thyrotropin (TSH) levels with the functional status of a nodule, and whether a sensitive TSH assay can be used in lieu of scintigraphy. METHODS: From 1990 to 1996, patients with a thyroid nodule were evaluated with FNAB and serum TSH measurement. Iodine-123 scintigraphy was reserved for patients without a definitive FNAB and was correlated with TSH levels. RESULTS: Of 356 patients with a thyroid nodule, 102 did not have a definitive FNAB. A hyperfunctioning nodule was diagnosed in 14 of the 102 patients. A low TSH level was detected in 12 (86%) of 14 patients with a hyperfunctioning nodule (mean = 0.04 +/- 0.38 microIU/mL) and only 20 (23%) of 88 patients with a hypofunctioning nodule (mean = 0.87 +/- 4.11 microIU/mL) (P < .05). Only 2 of 70 (2.8%) patients with a normal or increased TSH level had a hyperfunctioning nodule. CONCLUSIONS: A 14% incidence of hyperfunctioning nodules in patients without a definitive FNAB warrants the use of scintigraphy but only when serum TSH levels are low, thus avoiding unnecessary scans in 91% of patients with a thyroid nodule.     

Isolated thyroid nodule. Comparative value of cyto-puncture and scintigraphy

OBJECTIVES: Nodular thyroid disease, indicated by the presence of single or multiple nodules within the thyroid gland is a common clinical problem, the main question remains the malignancy. Radionuclide scanning, ultrasonography and fine needle aspiration biopsy have been helpful to distinguish benign from malignant nodules and to select patients for surgery. METHODS: We performed a prospective study to assess the comparative value of fine needle nonaspiration biopsy and thyroid scinti scan in the management of 412 patients operated for solitary thyroid nodule. RESULTS: Sensitivity and negative predictive values were the same for both methods, but specificity of cytology was greater than that of thyroid scinti scan (80.53% vs. 10.47%, p < 0.001). DISCUSSION: Thyroid radionuclide scanning remains valuable in the evaluation of a cytological benign solitary thyroid nodule when TSH value is low, in order to distinguish toxic adenoma from cold nodule in Graves' disease.     

Thyroxine suppressive therapy in patients with nodular thyroid disease

PURPOSE: To review evidence about thyroxine suppressive therapy in patients with thyroid nodules, including the clinical importance and natural history of nodules and the effects and potential side effects of thyroxine therapy. DATA SOURCES: English-language articles published from 1986 to December 1996 were identified through searches of the MEDLINE database, selected bibliographies, and personal files. DATA EXTRACTION: Randomized, controlled trials and nonrandomized trials of thyroxine suppressive therapy for solitary and predominantly solid thyroid nodules were reviewed. In most studies, nodule cytology was evaluated by fine-needle aspiration biopsy. Therapy was considered suppressive if suppression was documented by thyroid-stimulating hormone-releasing hormone tests or sensitive thyroid-stimulating hormone assays. Response was defined as a decrease of 50% or more in nodule size or volume; most recent studies measured nodule size by ultrasonography. DATA SYNTHESIS: The evidence suggests that thyroxine suppressive therapy fails to shrink most nodules: Only 10% to 20% of nodules responded to this treatment. Fine-needle aspiration biopsy is more reliable in distinguishing benign from malignant nodules. Recent studies suggest that spontaneous decrease in size with complete disappearance of thyroid nodules is not uncommon. No data show that thyroxine therapy arrests further growth in most existing nodules or prevents the emergence of new nodules. Postoperative thyroxine therapy does not seem to prevent recurrence of thyroid nodules except in patients with a history of radiation therapy. Potential adverse effects of long-term suppressive therapy include osteoporosis and heart disease. CONCLUSIONS: Patients with cytologically benign nodules are best followed without thyroxine treatment. Most benign nodules remain stable in size and remain benign when monitored for a long time. For nodules that increase in size, biopsy should be done again or surgery should be performed.     

Simultaneous occurrence of Graves' ophthalmopathy and autonomous thyroid nodules

Estimations regarding the simultaneous occurrence of Graves' ophthalmopathy and autonomously functioning thyroid nodules expect frequencies of 0.05-0.2%. Contrary to these estimated numbers, only 3 patients with these simultaneous manifestations were identified in an out patient thyroid clinic within a period of 10 years. The possible protection by the autonomous thyroid nodules against the manifestations of Graves' disease is discussed.     

An investigation into the prevalence of thyroid disease on Kwajalein Atoll, Marshall Islands

The prevalence of thyroid nodules and thyroid cancer was studied in the indigenous population residing on Ebeye Island, Kwajalein Atoll, in the Republic of the Marshall Islands. This island, centrally located in the nation, is home to about 25% of the nation's population, many who have migrated there from other atolls. The objective of the study was to obtain thyroid disease rate statistics on as much of the population as possible that was alive during the years of nuclear testing and to test the hypothesis that described a linearly decreasing prevalence of palpable nodules with increasing distance from the Bikini test site. 1,322 Marshallese born before 1965 were given a thyroid examination using neck palpation, fine needle aspiration biopsy, and high resolution ultrasound imaging. Approximately 40% of the total population living on this island who are at risk from exposure to radioactive fallout during the years 1946-1958 were screened. Of that group, 815 were alive at the time of the BRAVO test on 1 March 1954. Two hundred sixty-six people with thyroid nodules were found (32.6%): 132 were palpable nodules (16.2%), and 134 were nodules that could be diagnosed with ultrasound only (15.7%). Prevalence of palpable nodules was particularly high in men and women older than 60 y, in men who were 6 to 15 y of age at the time of the BRAVO test, and in women 1 to 10 y of age at the time of the BRAVO test. In 22 people, the clinical diagnosis was most likely cancer though histopathological evidence was only available from 11 operated cases. Of the 11 operated cases, 10 were cancer. Cancer prevalence was particularly high in those women born between 1944 and 1953 (7/220 = 3.2%), i.e., who were children during the early years of nuclear testing. The Ebeye data showed a marginally significant correlation between palpable nodule prevalence among women and distance to Bikini (r = -0.44, p = 0.06). This report summarizes the clinical findings of the thyroid examinations, the age distributions for nodular disease and cancer, and examines the relationship between prevalence of nodules and present day levels of 137Cs in the environment of each atoll.     

Thyroid disease among the Rongelap and Utirik population--an update

In 1954, 253 Marshallese were accidentally exposed to fallout radiation from the hydrogen bomb, BRAVO. The Marshall Islands Medical Program (MIMP) was established by the Department of Energy in 1955 to monitor and treat radiation-related disease pursuant to this accident. Medical teams from Brookhaven National Laboratory, a federal institution, regularly visit the Marshall Islands to give medical care to the exposed population. The most significant complication of the exposure has been found to be thyroid disease due to the ingestion of radioactive iodides from the fallout. In 1963 the first thyroid nodules were found in Rongelap subjects and in 1969 in Utirik. Non-neoplastic adenomatous nodules were associated with higher doses of radiation and neoplastic nodules developed in individuals receiving lower doses of radiation. Women were more susceptible to the development of palpable thyroid nodules than men. In 1994 the MIMP initiated examination of the thyroid by ultrasound to supplement the clinical examination. One hundred and sixty-four patients were evaluated. No significant differences were found in the incidence of thyroid nodules or the mean nodule count between the three groups of Rongelap and Utirik exposed and a comparison patient population. There was no significant difference in the incidence of thyroid nodules in males vs. females. Five exposed patients were referred for surgical excision of a nodule detected only by ultrasound. These ultrasound findings are unexpected in that females are known to have a higher incidence of thyroid disease than males and we expected that the incidence of ultrasound nodules would be higher in the exposed population.     

Effect of percutaneous ethanol injection therapy versus suppressive doses of L-thyroxine on benign solitary solid cold thyroid nodules: a randomized trial

The results of studies using suppressive doses of L-T4 on benign solitary solid cold thyroid nodules have been conflicting. Recently, intranodular injection of absolute ethanol has been proposed as an effective treatment, but has been evaluated only in uncontrolled studies. Our objective was to evaluate the effect of two alternative medical treatment modalities, percutaneous ethanol injection therapy and L-T4, on the benign solitary solid cold thyroid nodule. In a prospective randomized clinical trial, 50 euthyroid patients with a single solid colloid thyroid nodule causing local discomfort were assigned to a single intranodular injection of sterile 98% ethanol (n = 25) or suppressive doses of L-T4 (n = 25). We aimed at an ethanol dose of 20-50% of the pretreatment nodular volume. The initial daily dose of L-T4 was 1.5 microg/kg BW and was adjusted monthly during the first 6 months to reduce serum TSH to subnormal levels (<0.40 mU/L). Thyroid nodule volume and total thyroid volume were assessed by ultrasound, and thyroid function was determined by routine assays before and during follow-up. Symptom scores before and at 12 months were evaluated by a questionnaire rating pressure symptoms and cosmetic symptoms. The median ethanol dose given was 21% [95% confidence interval (CI), 18;25] of the pretreatment nodule volume. In this group, the median reduction in nodule volume was 47% (CI, 33;57; P < 0.0001) compared to 9% (CI, -7;22; P = 0.09) in the L-T4 group. The difference between the two treatment regimens was statistically significant (P < 0.0001). The median reduction in perinodular thyroid volume was 20% (CI, 11;31; P = 0.03) in the L-T4 group, whereas no change was seen in the ethanol group (-2.5%; CI, -18;11; P = 0.9). Fourteen of 25 (56%) patients treated with ethanol injection and 8 of 25 (32%) treated with L-T4 had complete relief of symptoms at 12 months of follow-up (P = 0.09). No major side-effects were seen in either group. Percutaneous ethanol injection therapy administered as a single small dose results in a satisfactory clinical response in approximately 50% of patients by halving the nodule volume. The thyroid nodule-reducing effect of L-T4 suppressive therapy is insignificant, but a subjective satisfactory clinical response is seen in a subgroup of patients, probably explained by the concomitant reduction of perinodular thyroid volume.     

Treatment of large cold benign thyroid nodules not eligible for surgery with percutaneous ethanol injection

We studied the effect of percutaneous ethanol injection (PEI) in the treatment of cold, cytologically benign, large (>10 mL) thyroid nodules (CBNs) in 41 patients. The end-point of our study was to evaluate the efficacy of PEI on: 1) local symptomatology, assessed by an arbitrary symptom score; and 2) nodule volume and tracheal displacement (at ultrasonography). Follow-up ranged from 12-36 (21 +/- 9) months. Symptom score was significantly reduced (P < 0.01) after 6 months and at the end of the follow-up (2.1 +/- 0.3 vs. 0.2 +/- 0.5 and vs. 0.2 +/- 0.4). A significant (P < 0.01) nodule volume reduction was observed, without differences between solid or mixed CBNs; the reduction was 50% or more in 92.7% of patients. Neither clinical parameters nor pretreatment nodule ultrasonographic features were related to nodule reduction. Disappearance or significant reduction (>0.5 cm) of tracheal displacement was obtained in 61% and in 39% of patients, respectively. One patient experienced prethyroid region edema, pain, and mild fewer, which reversed within 1 week; and one patient had dysphonia, caused by vocal cord palsy, which reversed spontaneously within 1 month. At the end of the follow-up, nodules with just necrotic material at cytology showed a greater (P < 0.05) volume reduction than nodules with residual benign thyroid cells. Our data suggest that PEI is a safe and effective treatment of large CBNs, although sometimes serious side effects do occur.     

Clinical significance of clonality in thyroid nodules

BACKGROUND: Many different neoplastic and hyperplastic thyroid diseases present with clinically apparent thyroid nodules. Clonality analysis indicates whether a nodule arises from the polyclonal proliferation of a group of cells or forms a clone from a genetically altered cell and thus provides objective information on the origin of the thyroid nodules. Clonality was studied in thyroid nodules using the polymerase chain reaction (PCR) assay in the X-linked human androgen receptor (HUMARA) gene by random X chromosome inactivation in women. METHODS: DNA samples were obtained from 28 nodules in 21 women. All nodules and non-tumour thyroid tissues were fractioned selectively under a cryostat. Genomic DNA was isolated and digested with HhaI. PCR amplification of the HUMARA locus was performed using PCR mixtures containing [alpha-32P]2'-deoxycytidine 5'-triphosphate. The PCR products were analysed by denaturing gel electrophoresis. RESULTS: The HUMARA alleles were heterogeneous in 18 of 21 patients. Among the 23 nodules from 18 patients, all of the eight papillary thyroid carcinomas were monoclonal. Two solitary nodules from follicular adenomas were monoclonal. Of the 13 follicular nodules from nodular goitres, ten were polyclonal and three were monoclonal. The monoclonal follicular nodules were larger in size (3.5 versus 2.0 cm, P< 0.05) and had a tendency towards more cystic changes than polyclonal nodules. CONCLUSION: PCR-based clonality study of thyroid nodules may help to distinguish hyperplastic from neoplastic nodules.     

Limb salvage procedures for lower extremity ischemia

A series of 348 patients undergoing operative intervention because of thyroid masses is reviewed. The incidence of primary malignancy among these patients is 16.4%. Male sex and the presence of cervical adenopathy significantly increase the probability of malignancy. The presence of multiple nodules or a functional nodule on radioiodine thyroid scan significantly reduces the probability of cancer. A rational approach to thyroid nodules is presented based on these findings and new modalities that have become available.     

Solitary thyroid nodule in Khartoum

Ninety four patients with solitary and significantly dominant thyroid nodules were studied. Inadequate sampling was reported in 5 patients (5.9%). In the remaining 89 patients, 64 had simple goitre (72%), 12 follicular adenoma (13.5%), 12 were malignant nodules (6 follicular, 5 papillary and one anaplastic) (13.5%) and one patient had Hashimoto's thyroiditis. The incidence of malignancy in the clinically solitary nodules was 14% (10/70) compared to 10% (2/19) for the dominant nodules which increased to 16% (8/49) versus 10% (4/40) respectively after ultrasonography and histopathological confirmation of the nature of the gland. There is a low positive predictive value for follicular neoplasm with fine needle aspiration cytology (FNAC) (44%). This is due to the fact that reports of suspicious follicular pattern is agreed not to imply definite malignancy, however total lobectomy was done for those patients whereas terms like "not suspicious" and "highly suspicious" are considered to mean, benign and malignant respectively and in those latter groups the prediction was 100%. The study stresses the importance of FNAC techniques in reducing the surgical load with minimal false negative results, increasing the yield of carcinoma and projecting the importance of a significantly dominant nodule in endemic areas.     

Morphological and functional polymorphism within clonal thyroid nodules

Thirty-nine thyroid nodules, removed because of recent growth, were analyzed morphologically by serial histological sections for the classical histomorphological hallmarks of follicular cell replication and for immunohistochemically demonstrable overexpression of the growth-associated ras-gene product p21ras. Clonal analysis was performed using the highly informative probe M27 beta that detects polymorphisms on the locus DXS255 of the X-chromosome. Twenty-four nodules were of clonal and 15 nodules were of poly-clonal origin. Only 3 out of the 24 clonal nodules were histomorphologically uniform. In all others, the structural hallmarks of active growth and the P21ras growth-marker expression were remarkably heterogeneous throughout the tumors. There were no histomorphological characteristics distinguishing these clonal tumors from polyclonal nodules. Even if a clonal thyroid tumor may be originally homogeneous in respect to the parameters studied here, mechanisms must exist that create wide heterogeneity of growth and of morphogenetic potential among the individual follicular cells during further expansion of the nodule. Thus, clonal nodules are much more common in nodular goiters than hitherto assumed on grounds of the classical morphological criteria. The diagnosis of a true monoclonal nodule can no longer rely on morphological and functional criteria alone but requires molecular or cytogenetic analysis of clonality.     

Suppressive therapy with levothyroxine for solitary thyroid nodules: a double-blind controlled clinical study and cumulative meta-analyses

Levothyroxine suppressive treatment of solitary thyroid nodules is controversial. A 1-yr prospective randomized placebo-controlled trial was conducted to evaluate the effect of T4 on nodule volume and bone mineral density, and meta-analyses were performed to examine the quantitative synthesis of data from similar designed controlled trials. Forty-five euthyroid patients (42 females, age range: 19-73 yr) with single, colloid nodules were randomized to T4 (21 patients, 2.7 +/- 0.3 microg/kg, TSH < 0.3 microIU/mL) and placebo. Ultrasonography and densitometry were performed at baseline and repeated after treatment. Mean nodule volume or bone mineral density did not change. Nodule reduction more than 50% was observed in 6 of 21 treated patients and 2 of 24 placebo patients (P = 0.12). This study and another 6 prospective controlled trials (minimum 6 months, ultrasonographic nodule evaluation) were included in cumulative meta-analyses (risk-difference method). Nodule volume decreased more than 50% in a significantly higher percentage of patients in the T4 groups (risk difference, 16.7%; 95% confidence intervals, 5.8-27.6%). Four trials evaluated nodule growth with homogeneous results (Q = 0.42). Nodule volume increased more than 50% in a significantly smaller percentage of patients treated with T4 (risk difference, 9.7%; 95% confidence intervals, 2.0-17.4%). In conclusion, T4 treatment is associated with decreased nodule volume in 17% of patients and may inhibit growth in another 10%.     

Utility of fine-needle aspiration cytology and frozen-section examination in the operative management of thyroid nodules

Fine-needle aspiration cytology has a high sensitivity for the diagnosis of solitary thyroid nodules. Certain diagnoses involving follicular histologies often cannot be made with needle biopsy alone. The utility of frozen-section examination of thyroid nodules, with particular regard to those lesions with follicular histologies, is also limited. We examined the correlation of fine-needle aspiration cytology and frozen-section examination in solitary thyroid nodules to determine the contribution of frozen-section examination to the operation. We reviewed the fine-needle aspiration cytology, frozen-section examination, and final pathology of 100 consecutive patients undergoing thyroidectomy for a solitary solid thyroid nodule in an 4-year period. The diagnoses were classified as indeterminant, benign, or malignant. The utility and impact of the diagnosis from fine-needle aspiration or frozen section on the operative procedure performed was analyzed. Fine-needle aspiration cytology as a diagnostic test for thyroid nodules demonstrated an indeterminant rate of 23 per cent, with a diagnostic accuracy of 77 and 92 per cent for benign and malignant disease, respectively. In all patients with inaccurate benign diagnosis on fine-needle aspiration cytology, follicular neoplasm was misinterpreted for follicular adenoma or multinodular goiter. In comparing frozen-section results, the indeterminant, benign, and malignant rates were 7, 96, and 64 per cent, respectively. Of the 23 patients with indeterminant results on fine-needle aspiration cytology, the intraoperative frozen-section diagnosis on 4 patients was deferred to permanent section; 18 received accurate cytological diagnosis; and in 1 patient, carcinoma was missed. Overall, the decision about the extent of surgical thyroid resection was changed in only 2 patients based on the frozen-section results. Preoperative evaluation with fine-needle aspiration cytology can accurately and appropriately define the extent of thyroid surgery in most patients with a diagnosis of malignant neoplasm or benign disease. Intraoperative frozen-section examination may be helpful if fine-needle aspiration cytology results are inderminant and in cases of follicular histology as an adjunct for evaluation of the thyroid nodule, but overall, frozen section does not contribute to the management of the thyroid lesion at the time of surgery.     

Changes in radioiodine turnover in patients with autonomous thyroid adenoma treated with percutaneous ethanol injection

In 24 patients with autonomous thyroid adenoma, we studied the hormonal pattern (free thyroxine, free triiodothyronine and thyroid stimulating hormone) and markers of radioiodine turnover before and after nodule ablation with percutaneous ethanol injection. METHODS: The hormonal pattern was studied before treatment and at various intervals after nodule ablation. Changes in radioiodine turnover were studied measuring 131I protein-bound iodine and the biologic half-life of radioiodine in the thyroid (calculated from thyroid uptake at 24 and 48 hr) before and after ethanol treatment. RESULTS: The hormonal pattern was normalized by treatment in all patients and remained normal for the follow-up period. Before treatment, protein-bound 131I was elevated in all patients but 4; after treatment, it normalized in 15 patients with the disappearance of the adenoma on scintigraphy. In the remaining 9 patients with only partial nodule destruction on scintigraphy, protein-bound 131I remained elevated although markedly reduced. Biologic half-life was shortened in 18 of 24 patients before treatment; after treatment, it was normal in 18 of 24 patients (13 of 15 with complete nodule ablation and 5 of 9 with partial ablation). CONCLUSION: Ethanol treatment normalized the hormonal pattern in all patients. Measures of radioiodine turnover were better markers of residual disease in that they normalized in almost all patients with complete nodule ablation, whereas they remained abnormal in a high proportion of patients with incomplete ablation. Thyroid hormones remained normal over a follow-up period of 3-7 yr in all patients.