Coexistent Hashimoto's thyroiditis with papillary thyroid carcinoma: impact on presentation, management, and outcome

Papillary thyroid cancer, although strongly associated with lymphocytic infiltration on histology, is only weakly predicted by serum thyroid auto-antibodies in patients with nodular thyroid diseases

OBJECTIVE

We evaluated the association between thyroid autoimmunity and thyroid cancer in a retrospective series of unselected thyroid nodules submitted to fine-needle aspiration (FNA) cytology.

DESIGN

Anti-thyroid antibodies (TAb) were measured in patients with multinodular goiter (MNG) and single/isolated thyroid nodule (S/I) submitted to FNA. Thyroid lymphocytic infiltration (LI) on histology was studied in a subgroup of patients submitted to thyroidectomy; 13,021 patients were included: on cytology 622 had papillary thyroid cancer (c- PTC) and 12,399 benign thyroid nodular diseases (c-BTN). LI was evaluated in histological samples of 688 patients: 304 with PTC (h-PTC) and 384 with BTN (h-BTN).

RESULTS

TAb prevalence was not different in c-BTN and c-PTC (38.7% vs 35.6%). TAb were more frequent in c-BTN than c-PTC in females with MNG (40.1% vs 32.5%, p=0.02), and in c-PTC than in c-BTN in males with S/I (31.2% vs 20.4%, p=0.02) and, although not significantly, in females younger than 30 yr (35.1% vs 30.7%). The frequency and severity of LI was significantly higher in h-PTC than h-BTN, both in MNG (82.5% vs 45.0%, p<0.001) and S/I (85.6% vs 71.0%, p<0.001), but a higher number of patients with h-PTC had negative circulating TAb, despite the presence of moderate/severe LI.

CONCLUSIONS

TAb are weakly associated to PTC in males and young females, while they are more frequent in older females with BTN. The frequency and severity of LI is significantly higher in PTC than in BTN, but in cancer patients TAb are frequently negative, despite the evidence of histological thyroiditis. These data suggest that different kinds of immune response may be involved in PTC and BTN.

Comparison of malignancy rate in thyroid nodules with cytology of indeterminate follicular or indeterminate Hürthle cell neoplasm

BACKGROUND

Thyroid nodules that are read on cytology as follicular or Hürthle cell neoplasms (FN and HN, respectively) and indeterminate for malignancy require surgery to differentiate benign from malignant nodules. We analyzed FN and HN with indeterminate cytology to determine if there were differences in the rate and types of thyroid malignancy and if the rate of thyroid malignancy was influenced by age or sex.

METHODS

We analyzed 463 nodules with an indeterminate cytological diagnosis of FN and 140 nodules with an indeterminate cytological diagnosis of HN. The histopathological diagnosis after thyroidectomy was the method for establishing the diagnosis and type of malignancy.

RESULTS

For the entire series of 603 patients there were 106 (17.6%) with thyroid cancer; 80 of these had a cytology reading of FN and 26 had HN. Extrathyroidal invasion in the grouped HN and FN patients who had papillary thyroid carcinoma (PTC) was more common in females than in males (62% vs. 25 %, p < 0.05). The rate of thyroid cancer was similar in FN (17.3%) and HN (18.6%). The rate of Hürthle cell thyroid cancer was significantly higher in HN than in FN (5.0% vs. 0.7%, p < 0.01) and the rate of the oncocytic variant of PTC was also significantly greater in HN compared to FN nodules (23.1% vs. 1.7%, p < 0.05). The rate of follicular thyroid carcinoma was almost identical in patients with HN and FN (19.2% vs. 18.8 %).

CONCLUSIONS

There is little difference in the rate of malignancy between thyroid nodules with a cytological reading of FN indeterminate for malignancy and HN indeterminate for malignancy but there is a difference in the types of thyroid cancers in these groups. Hürthle cell thyroid cancer and the oncocytic variant of PTC is more common in nodules with an HN indeterminate for malignancy cytology reading than in nodules with a FN indeterminate for malignancy cytology reading. Since Hürthle cell thyroid cancer and the oncocytic variant of PTC are more aggressive than other thyroid cancers, it is likely that patients with an HN indeterminate for malignancy cytology will, as a group, have more aggressive thyroid cancers than those with an FN indeterminate for malignancy cytology.

Clinical and pathological features and the BRAF(V600E) mutation in patients with papillary thyroid carcinoma with and without concurrent Hashimoto thyroiditis

BACKGROUND

It has been reported that patients with papillary thyroid carcinoma (PTC) have a high incidence of background Hashimoto thyroiditis (HT); however, the linkage of HT to PTC is controversial. Recent studies have shown that the prevalence of activating point mutations in BRAFV600E is much higher (73-86%) in Korea than in Western countries (29-69%), and associated with a poor prognosis in PTC. The purpose of the present study was to investigate the frequency of the BRAFV600E mutation in PTC with and without HT, and to determine clinical and pathological features that were associated with concomitant HT and PTC.

METHODS

Fine-needle aspiration slides from 101 patients with surgically confirmed PTC were studied. The DNA was extracted from the atypical cells that were scraped from slides. It was then analyzed for the BRAFV600E mutation by pyrosequencing. In addition, the presence of background HT in surgical specimens and other clinical and pathological features of the patients were characterized.

RESULTS

HT was present in 37 (36.6%) of the patients. The BRAFV600E mutation was present in 27 (72.9%) of patients with HT but was present in 61 (95.3%) of patients without HT ( p#0.01). The inverse correlation of concurrent HT with the BRAFV600E mutation was significant for both males and females ( p < 0.01). The presence of background HT was not associated with tumor size, extrathyroidal invasion, lymph node (LN) metastasis, or tumor stage. The patients were younger in the group without background HT (44.1 +/- 13.2 vs. 49.8 +/- 13.9, p 1/40.05). The BRAFV600E mutation was present in 88 (87.1%) of the 101 patients with PTC. The presence of the BRAFV600E mutation was significantly associated with LN metastasis ( p < 0.02; odds ratio, 6.24; 95% confidence interval, 1.51-25.79).

CONCLUSION

In Korean patients with PTC, the BRAFV600E mutation is associated with a lower frequency of background HT and a high frequency of LN metastasis.

Papillary microcarcinoma

Background

Papillary microcarcinoma (PMC) is increasing in incidence because of diagnosis by ultrasound-guided fine-needle aspiration cytology.

Methods

Between January 1966 and December 1995, we treated 6019 patients with papillary cancer; among them, 2070 patients with PMC were studied.

Results

PMC is essentially very similar to papillary cancer that is 11 mm or larger and has a very good prognosis. Smaller tumors and younger patients have a better prognosis. Among PMC, larger tumors (6–10 mm) recur in 14% at 35 years compared with 3.3% in patients with smaller tumors. Patients older than 55 years have recurrence in 40% at 30 years, with a worse prognosis than younger patients who have a recurrence rate of less than 10%. Extracapsular invasion by the primary tumor also has a higher recurrence rate. The majority of recurrences are in the neck. Therefore, annual ultrasound of the neck is effective for recurrence surveillance.

Conclusion

Papillary microcarcinoma is similar to larger papillary carcinomas with tumor characteristics and age-based recurrence rate that extends for many years, justifying long surveillance after surgery.

Endogenous thyrotropin and triiodothyronine concentrations in individuals with thyroid cancer

BACKGROUND

Thyroid hormone suppression therapy is associated with decreased recurrence rates and improved survival in patients with differentiated thyroid cancer. Recently higher baseline thyrotropin (TSH) levels have been found to be associated with a postoperative diagnosis of differentiated thyroid cancer. Our objective was to confirm whether preoperative TSH levels were higher in patients who were diagnosed with differentiated thyroid cancer after undergoing thyroidectomy, compared with patients who were found to have benign disease. We also sought to determine whether thyroid hormone levels were lower in the patients with malignancy.

METHODS

The study was a retrospective analysis of a prospective study. The study setting was the General Clinical Research Center of an Academic Medical Center. Participants were 50 euthyroid patients undergoing thyroidectomy. Thyroxine, triiodothyronine (T(3)), and TSH levels were documented in patients prior to their scheduled thyroidectomy. Following thyroidectomy, patients were divided into those with a histologic diagnosis of either differentiated thyroid cancer or benign disease. Preoperative thyroid profiles were correlated with patients' postoperative diagnoses.

RESULTS

All patients had a normal serum TSH concentration preoperatively. One-third of the group was diagnosed with thyroid cancer as a result of their thyroidectomy. These patients had a higher serum TSH level (mean = 1.50 mIU/L, CI 1.22-1.78 mIU/L) than patients with benign disease (mean = 1.01 mIU/mL, CI 0.84-1.18 mIU/L). There was a greater risk of having thyroid cancer in patients with TSH levels in the upper three quartiles of TSH values, compared with patients with TSH concentrations in the lowest quartile of TSH values (odd ratio = 8.7, CI 2.2-33.7). Patients with a thyroid cancer diagnosis also had lower T(3) concentrations measured by liquid chromatography tandem mass spectrometry (mean = 112.6 ng/dL, CI 103.8-121.4 ng/dL) than did patients with a benign diagnosis (mean 129.9 ng/dL, CI 121.4-138.4 ng/dL).

CONCLUSION

These data confirm that higher TSH concentrations, even within the normal range, are associated with a subsequent diagnosis of thyroid cancer in individuals with thyroid abnormalities. This further supports the hypothesis that TSH stimulates the growth or development of thyroid malignancy during its early or preclinical phase. We also show for the first time that patients with thyroid cancer also have lower T(3) levels than patients with benign disease.

Thyroidectomy for Hashimoto's thyroiditis: complications and associated cancers

BACKGROUND

Hashimoto's thyroiditis is usually treated medically; however, thyroidectomy is sometimes indicated. Thyroiditis can make thyroid dissection more difficult and possibly increase the risk of surgical complications. The aim of this study was to determine the rate of complications and associated cancer in patients with Hashimoto's thyroiditis.

METHODS

Retrospective series of 474 patients treated surgically at the University of California, San Francisco, between January 1985 and June 2005 with final pathology demonstrating Hashimoto's thyroiditis, chronic lymphocytic thyroiditis, or chronic thyroiditis. Parameters evaluated included demographics, surgical indications, and postoperative complications.

RESULTS

Among the 474 patients, 133 had thyroidectomy because of preoperative diagnosis of thyroid cancers (median age 39 years; 116 females and 17 males), 316 had thyroidectomy because of benign thyroid nodules or goiter (median age 47.5 years; 292 females and 24 males), and 25 had thyroidectomy to relieve local symptoms caused by thyroiditis but did not have thyroid nodules (median age 42 years; 25 females). No death or permanent surgical complications occurred. One hundred and fifty-two patients (32.1%) had transient postoperative hypocalcemia, 2 (0.4%) had transient recurrent nerve palsy, and 4 (0.8%) had a postoperative neck hematoma. Fifty-three percent had thyroid cancer at final histological examination.

CONCLUSIONS

Thyroidectomy can be performed in patients with Hashimoto's thyroiditis with a low risk of permanent surgical complications. Cancer is common in patients who have a thyroidectomy for Hashimoto's thyroiditis even when not suspected preoperatively.

The role of intraoperative frozen section if suspicious for papillary thyroid cancer

BACKGROUND

Optimal surgical intervention is straightforward when a fine-needle aspiration (FNA) is diagnostic for papillary thyroid cancer (PTC). However, if there are characteristics of an aspirate suspicious for PTC but not meeting criteria for diagnosis of PTC, the management is less clear.

METHODS

Of the 1,051 patients who underwent thyroid surgery at the University of Wisconsin between May 24, 1994, and October 21, 2004, 102 had preoperative FNA cytology that was diagnostic or suspicious for PTC. Within the subgroups of diagnostic for PTC and suspicious for PTC, we evaluated the accuracy of FNA, the utility of frozen section (FS), and the predictive value of demographic and pathologic variables.

RESULTS

When diagnostic for PTC, FNA was 97% accurate and FS did not alter management. However, if an FNA was interpreted as suspicious for PTC, there was a 57% (17/30) likelihood of PTC on permanent histology. In this subgroup, FS led to the optimal operative procedure in 96% (25/26) of cases. With the exception of size greater than 4 cm, demographic and pathologic variables did not predict malignancy or increase the likelihood of an FNA being diagnostic for PTC.

CONCLUSION

Intraoperative FS is a useful diagnostic tool when an FNA is suspicious for PTC.

Higher serum thyroid stimulating hormone level in thyroid nodule patients is associated with greater risks of differentiated thyroid cancer and advanced tumor stage

CONTEXT

TSH is a known thyroid growth factor, but the pathogenic role of TSH in thyroid oncogenesis is unclear.

OBJECTIVE

The aim was to examine the relationship between preoperative TSH and differentiated thyroid cancer (DTC).

DESIGN

The design was a retrospective cohort.

SETTING, PARTICIPANTS

Between May 1994 and January 2007, 1198 patients underwent thyroid surgery at a single hospital. Data from the 843 patients with preoperative serum TSH concentration were recorded.

MAIN OUTCOME MEASURES

Serum TSH concentration was measured with a sensitive assay. Diagnoses of DTC vs. benign thyroid disease were based on surgical pathology reports.

RESULTS

Twenty-nine percent of patients (241 of 843) had DTC on final pathology. On both univariate and multivariable analyses, risk of malignancy correlated with higher TSH level (P=0.007). The likelihood of malignancy was 16% (nine of 55) when TSH was less than 0.06 mIU/liter vs. 52% (15 of 29) when 5.00 mIU/liter or greater (P=0.001). When TSH was between 0.40 and 1.39 mIU/liter, the likelihood of malignancy was 25% (85 of 347) vs. 35% (109 of 308) when TSH was between 1.40 and 4.99 mIU/liter (P=0.002). The mean TSH was 4.9+/-1.5 mIU/liter in patients with stage III/IV disease vs. 2.1+/-0.2 mIU/liter in patients with stage I/II disease (P=0.002).

CONCLUSIONS

The likelihood of thyroid cancer increases with higher serum TSH concentration. Even within normal TSH ranges, a TSH level above the population mean is associated with significantly greater likelihood of thyroid cancer than a TSH below the mean. Shown for the first time, higher TSH level is associated with advanced stage DTC.

[Coexistence of Hashimoto's thyroiditis and papillary thyroidal carcinoma with papillary carcinoma of thyreoglossal duct]

BACKGROUND

Simultaneous presence of Hashimoto's thyroiditis and papillary thyroidal carcinoma in thyroidal gland with papillary carcinoma association in thyroglossal duct is quite rare. The questions like where the original site of primary process, is where metastasis is, what the cause of coexisting of these diseasesis present a diagnostic dilemma.

CASE REPORT

We presented a case of a 53-year old female patient, with the diagnosis of Hashimoto's thyroiditis and symptoms of subclinical hypothyreosis and nodal changes in the right lobe of thyroidal gland, according to clinical investigation. Morphological examination of thyroidal gland, ultrasound examination and scintigraphy with technetium (Tc) confirmed the existence of nonhomogenic tissue with parenchyma nodular changes in the right lobe of thyroidal gland that weakly bonded Tc. Fine needle biopsy in nodal changes, with cytological analyses showed no evidence of atypical thyreocites. Hashimoto's thyroiditis was confirmed on the basis of the increased values of anti-microsomal antibodies, the high levels of thyreogobulin 117 ng/ml and TSH 6.29 microIU/ml. The operation near by the nodular change in the right lobe of thyroidal gland revealed pyramidal lobe spread in the thyroglossal duct. Total thyroidectomia was done with the elimination of thyroglossal duct. Final patohystological findings showed papillary carcinoma in the nodal changes pT2, N0 and in the thyroglossal duct with the presence of Hashimoto's thyroiditis in the residual parenchyme of the thyroid gland. After the surgery the whole body scintigraphy with iodine 131 (131I) did not reveal accumulation of 131I in the body, while the fixation in the neck was 1%. After that, the patient was treated with thyroxin with suppression-substitution doses.

CONCLUSION

Abnormality in embrional development of thyroidal tissue might be the source of thyroidal carcinoma or the way of spreading of metastasis of primary thyroidal carcinoma from thyroid gland. The cause of this process is most probably a hereditary mutation in RET oncogenes.

Is Hashimoto's thyroiditis a risk factor for papillary thyroid cancer?

BACKGROUND

Hashimoto's thyroiditis (HT) is the most common cause of hypothyroidism and is characterized by gradual autoimmune mediated thyroid failure with occasional goiter development. HT is seven times more likely to occur in women than in men. Papillary thyroid cancer (PTC), the most prevalent form of cancer in the thyroid, is 2.5 times more likely to develop in women than men. Given the relatively high prevalence of these diseases and the increased occurrence in women, we analyzed data from our institution to determine if there is a correlation between Hashimoto's thyroiditis and PTC in women.

METHODS

From May 1994 to January 2007, 1198 patients underwent thyroid surgery at our institution. Of these, 217 patients were diagnosed with HT (196 women, 21 men). The data from these patients were statistically analyzed using SPSS.

RESULTS

PTC occurred in 63 of 217 (29%) HT patients and 230 of 981 (23%) patients without HT (P = 0.051). Of these groups, 41 (65%) and 158 (69%) patients, respectively, had tumor sizes >/=1.0 cm; 56/196 women (29%) with HT had coexistent PTC compared with 160/730 women (22%) without HT (P = 0.03). Among women with any type of thyroid malignancy, 56/59 cases (95%) with HT had PTC compared with 159/196 cases (81%) in women without HT (P = 0.006). Additionally, female HT patients with goiters had a significantly lower rate of PTC (9% versus 36%, P < 0.001) compared with women without goiters. These differences were not observed in men with HT.

CONCLUSIONS

These data demonstrate that HT is associated with an increased risk of developing PTC. Female patients with HT undergoing thyroidectomy are 30% more likely to have PTC. Thus, more aggressive surveillance for PTC may be indicated in patients with HT, especially in women.

Clinical features of thyroid autoimmunity are associated with thyroiditis on histology and are not predictive of malignancy in 570 patients with indeterminate nodules on cytology who had a thyroidectomy

BACKGROUND

The relationship between thyroid autoimmunity and cancer is still uncertain.

PATIENTS

We approached this issue in 570 consecutive patients submitted to thyroidectomy for an indeterminate nodule on cytology. Thyroid autoimmunity was defined as positivity of circulating thyroid autoantibodies (TAb), autoimmune hypo- or hyperthyroidism, thyroid hypoechogenicity on ultrasound, and lymphocytic infiltration on histology.

RESULTS

TAb were found in 122/570 (21.4%), hypoechogenicity in 115/570 (20.1%), and lymphocytic infiltration in 117/570 (20.5%) of patients. The three features of thyroid autoimmunity were highly concordant: hypoechogenicity was observed in 71/448 (15.8%) patients with negative TAb and in 44/122 (36%) with positive TAb (P < 0.0001); lymphocytic infiltration was found in 53/448 (11.8%) patients with negative TAb and in 64/122 (52.4%) with positive TAb (P < 0.0001); hypoechogenicity on ultrasound was observed in 73/453 (16.1%) patients without, and in 42/117 (35.9%) with lymphocytic infiltration (P < 0.0001). None of these parameters was associated with malignancy. TAb were found in 32/135 (23.7%) patients with carcinoma and in 90/435 (20.6%) with a benign lesion (P = NS); hypoechogenicity was observed in 26/135 (19.2%) patients with carcinoma and in 89/435 (20.4%) patients with benign lesions (P = NS); lymphocytic infiltration was present in 28/135 (20.7%) patients with carcinoma and in 89/435 (20.4%) with benign lesions (P = NS). The frequency of cancer in 11 patients with clinically overt thyroid autoimmune disease did not differ from that observed in the whole study group.

CONCLUSION

In this group of patients with indeterminate thyroid nodules at cytology, clinical and pathological criteria of thyroid autoimmunity were strongly concordant and not associated with malignancy.

Total thyroidectomy for the treatment of Hashimoto's thyroiditis coexisting with papillary thyroid carcinoma

The coexistence of Hashimoto's thyroiditis (HT) and papillary thyroid carcinoma (PTC) is controversial. This study was conducted to evaluate the correlation between HT and PTC and to identify predictive factors for the coexistence of PTC and HT. A total of 922 patients underwent surgery for thyroid disorders between January 2001 and August 2005. In all, 199 patients had been diagnosed with PTC, 37 of whom had coexistent HT; in 689 patients, benign thyroid disease had been diagnosed. Patients' age and sex, as well as histopathology, tumor size, nodal involvement status, multicentricity, presence of metastasis, and serum thyroglobulin levels, were retrospectively reviewed. A significant correlation was observed between HT and PTC, although no statistical significance was noted between PTC and HT type (nodular or diffuse). Most patients with PTC+HT were female and younger (<40 y old) than those with PTC only. The rate of occult tumor in patients with PTC+HT was higher than that in patients with PTC alone. Data indicate the coexistence of PTC and HT and suggest that PTC may develop even in cases of diffuse HT. Total thyroidectomy is the surgical procedure of choice, especially in young, female patients with HT.

Increased incidence of well-differentiated thyroid cancer associated with Hashimoto thyroiditis and the role of the PI3k/Akt pathway

BACKGROUND

The link between inflammation and cancer is well-established, but the link between Hashimoto thyroiditis (HT) and thyroid cancer remains controversial. The purpose of our study was to determine the incidence of patients with thyroid cancer and associated HT at our institution, to correlate our patient population demographics with the Surveillance, Epidemiology and End Results (SEER) database, and to assess the expression of the phosphatidylinositol 3-kinase (PI3K)/Akt pathway in patients with HT.

STUDY DESIGN

Demographic and histologic data were collected from patients undergoing thyroid resection at the University of Texas Medical Branch from 1987 to 2002 and compared with the SEER database. Immunohistochemistry for phosphorylated Akt (a marker of PI3K activity), Akt isoforms and PTEN (an inhibitor of PI3K) was performed on paraffin-embedded blocks of resected thyroid tissue.

RESULTS

Our patient population demographics and thyroid cancer incidence by histologic type were similar to patients in the SEER database. Ninety-eight (37.7%) resected specimens had pathologic changes consistent with HT; 43 (43.8%) had an associated well-differentiated thyroid cancer. Increased phosphorylated Akt, Akt1, and Akt2 expression was noted in regions of HT and thyroid cancer compared with regions of normal surrounding thyroid tissue.

CONCLUSIONS

Patients with HT were three times more likely to have thyroid cancer, suggesting a strong link between chronic inflammation and cancer development. PI3K/Akt expression was increased in both HT and well-differentiated thyroid cancer, suggesting a possible molecular mechanism for thyroid carcinogenesis.

Concomitância da tireoidite de Hashimoto e o carcinoma diferenciado da tireóide

OBJETIVO: Avaliar a associação da tireoidite auto-imune e o carcinoma diferenciado da tireóide na Santa Casa de Misericórdia de Goiânia-Goiás. MÉTODO: De 1395 tireoidectomias realizadas de 1994 a 2003, foram selecionadas 120 carcinomas diferenciados (27 foliculares e 93 papilíferos). Foram avaliadas as variáveis clínicas (idade e sexo) com apresentação de freqüências e de sumários de medidas-resumo na descrição estatística. Para aferir a associação de tireoidite auto-imune e carcinoma diferenciado da tireóide em função dos achados histopatológicos, utilizou-se tabelas de contingência e análise pelo teste não paramétrico do quiquadrado de Pearson. Em todos os testes estatísticos foi adotado um nível de significância de 5% (p<0,05). RESULTADOS: 11,1% dos carcinomas foliculares e 18,3% dos carcinomas papilíferos estão associados à tireoidite auto-imune. Existe uma relação de freqüências quatro vezes maior da tireoidite auto-imune com o carcinoma diferenciado da tireóide em comparação com outras doenças tireoideanas (16,7% X 3,6%). CONCLUSÕES: Tais resultados permitem inferir que a associação entre a tireoidite auto-imune e o carcinoma diferenciado da tireóide é mais que casual, exigindo uma observação clínico-laboratorial cuidadosa nos portadores da doença auto-imune.

Inherited aspects of papillary thyroid carcinoma

The presence of papillary carcinoma of the thyroid in multiple generations of one kindred is a statistical impossibility as an occurrence of chance. However, traditional and molecular genetic analyses to date have failed to support the notion of a single gene mutation or identify one, in distinct contrast to medullary carcinoma of the thyroid. Findings to date, outside of distinct multicancer syndromes, suggest the interplay of inherited susceptibility and other factors, such as environmental exposures. It is possible that the main identifiable genetic risk factors at this time are the presence of multinodular goiter or Hashimoto's thyroiditis within the family.

Increased risk of papillary thyroid cancer in celiac disease

Patients with celiac disease have an increased rate of malignancies that are not limited to lymphomas. Thyroid carcinoma has not previously been associated with celiac disease. However, among a cohort of patients with celiac disease, we identified an increased risk of papillary carcinoma of the thyroid, standard morbidity ratio of 22.52 (95% confidence interval 14.90-34.04; P < .001), compared to United States national surveillance data. These patients were on a gluten-free diet. Only 1 had Hashimoto's thyroiditis, suggesting that mechanisms apart from autoimmune thyroiditis contribute to the increased risk of carcinoma of the thyroid in celiac disease.

Carcinome de la thyroïdeet thyroïdite de Hashimoto

OBJECTIVES

To study of the association between thyroid carcinoma and Hashimoto's thyroiditis (HT).

MATERIAL AND METHODS

[corrected] Retrospective study of 78 patients undergoing surgery between 2001 and 2002, with a pathological diagnosis of Hashimoto's thyroiditis. The clinical data and complementary tests performed before surgery are reported.

RESULTS

The mean age was 44.6 years, with 77 females and only one male. There were 12 cases of thyroid cancer associated with HT, mostly with the nodular form, with 11 papillary carcinoma (14.1%) and one non-hodgkin B lymphoma of the thyroid. Tumor size varied from 4 to 60 mm with a mean of 26 mm. There was one microcancer (size<10 mm).

CONCLUSIONS

We did not find an increased incidence of thyroid cancer associated with this highly selected population of HT patients.

Hashimoto Thyroiditis Coexistent with Papillary Thyroid Carcinoma

Several studies report a higher rate of papillary thyroid carcinomas (PTC) in patients with Hashimoto thyroiditis (HT), indicating a possible correlation between the two diseases. We studied a group of 89 subjects undergoing surgery for thyroid carcinomas compared with a control group of 89 subjects operated on for normofunctioning goiter, and a second group of 47 patients undergoing total thyroidectomy for HT. Association with HT was found in 19 of the 71 PTC subjects (26.7%) and in 8 goiter patients (8.9%), which was a significant difference ( P < 0.02). Thirteen of the HT patients, mostly with the nodular form, showed coexistent PTC (27.6%). HT and PTC coexisted in several morphological, immunohistochemical, and biomolecular aspects; increased incidence of PTC in HT patients might therefore indicate that HT is a precursor of thyroid cancer. Further studies are required, however, in order to confirm this hypothesis; until then, HT patients should undergo careful clinical and technical follow-up.

Hashimoto's thyroiditis with papillary thyroid carcinoma (PTC)-like nuclear alterations express molecular markers of PTC

AIMS

Focal papillary thyroid carcinoma (PTC)-like nuclear alterations have been documented in Hashimoto's thyroiditis; however, the molecular association between PTC and Hashimoto's thyroiditis is poorly understood. The aim of this study was to determine whether molecular expression patterns of PTC are present in association with PTC-like nuclear alterations in Hashimoto's thyroiditis.

METHODS AND RESULTS

The expression of four genes known to be up-regulated in PTC [LGALS3 (galectin3), CITED1, KRT19 (cytokeratin 19) and FN1 (fibronectin-1)] and the human mesothelial cell protein identified by monoclonal antibody HBME1 was evaluated. Immunohistochemistry was performed on 23 cases of Hashimoto's thyroiditis with focal or diffuse Hürthle cell change and PTC-like nuclear alterations, 37 PTC and 18 normal thyroids. Focal expression of galectin3 (GAL3), CITED1, cytokeratin 19 (CK19), HBME1 and fibronectin-1 (FN1) was seen in 87%, 65%, 43%, 26% and 17% of Hashimoto's thyroiditis, respectively, only in thyrocytes showing PTC-like nuclear alterations. In contrast, diffuse expression of GAL3, CITED1, CK19, HBME1 and FN1 was seen in 100%, 95%, 70%, 87% and 89% of PTC, respectively. Normal thyroid tissues did not express any of these proteins. Following immunohistochemistry, four Hashimoto's thyroiditis cases were found to contain foci of PTC. These foci were highlighted by the diffuse and strong expression of PTC-associated proteins, which prompted additional retrospective scrutiny of the haematoxylin and eosin-stained sections leading to appreciation of complete PTC-type nuclear atypia.

CONCLUSIONS

Focal PTC-like immunophenotypic changes in Hashimoto's thyroiditis suggest the possibility of early, focal premalignant transformation in some cases of Hashimoto's thyroiditis.

Lymphocytic infiltration in pediatric thyroid carcinomas

Lymphocytic thyroiditis has been associated with an increase in the incidence of thyroid papillary carcinoma in some reports, mostly series of both adults and children. Relatively little is written about thyroiditis and follicular carcinomas. We have seen several cases of pediatric follicular thyroid carcinomas, that had an associated lymphocytic infiltrate, which led us to examine all primary malignant thyroid neoplasms in our surgical files from 1984 through 2000 to examine this relationship. We also investigated the nature of the lymphocytic infiltrate with routine immunohistochemistry. Ten patients (five male, five female, ages 4.5-21 years of age) had a thyroid carcinoma resection, six (three males and three females) with papillary carcinoma and four patients (two males and two females) with low-grade follicular carcinoma. Seven samples (one male had two cases with tumor) from patients who had a papillary carcinoma resection with tissue blocks available were identified (one patient had slides but no blocks), as were all four patients with a follicular carcinoma. The thyroid of all patients with a follicular carcinoma contained a lymphocytic infiltrate; only four of the seven papillary carcinoma samples had an associated lymphoid infiltrate. In all cases with a lymphoid infiltrate, the infiltrate was present in both lobes (both adjacent and separate from the tumor). B lymphocytes were present in the lymphoid infiltrate of three of four patients with follicular carcinomas and in 1 of 3 cases of papillary carcinomas. T cells were dispersed throughout all the tumors with lymphoid infiltrates. We conclude that pediatric follicular carcinomas have an associated lymphocytic infiltrate in the tumor and/or adjacent thyroid, more commonly than papillary carcinomas.

Impact of previous thyroid autoimmune diseases on prognosis of patients with well-differentiated thyroid cancer

Autoimmune phenomena are frequently associated with differentiated thyroid carcinomas. However, the significance of thyroid gland autoimmune aggression on the outcome of these patients is still controversial. To address this issue, we studied 173 patients (123 with papillary and 50 with follicular carcinomas) who underwent surgery complemented by radioiodine ablation and followed up for 0.5-29 (6 +/- 5.76) years. Analysis of the prognostic factors revealed that higher age, male gender, larger nodule size, follicular tumors, presence of metastases at diagnosis, grade of differentiation, and stage correlated positively with the occurrence of death, metastasis and/or recurrence, while the presence of antibodies and the previous history of autoimmune disease correlated negatively with these events. Long distant metastases increased the odds for a lower disease-free rate for patients with papillary (8.366 times) and follicular (7.373 times) carcinoma. However, univariate and multivariate analysis failed to demonstrate that neck node involvement could influence the outcome for patients with well-differentiated thyroid carcinoma. The odds for patients with previous history of thyroid autoimmune disease (p < 0.02) or with thyroid autoantibodies (p < 0.001) to have a worse outcome were lower than for patients with no evidence of autoimmune activity, suggesting that autoimmune activity against the gland may exert a protective effect on the outcome of differentiated thyroid carcinoma patients.

Surgical therapy in Hashimoto's thyroiditis

Hashimoto's thyroiditis (HT) is usually considered to be manageable by levothyroxine (L-T4) administration, which can reduce the thyroid volume and supplement the lack of hormone. However, we sometimes encounter a huge goiter that has not shrunk in response to L-T4 therapy. These goiters continue to produce symptoms of compression and an unsightly appearance. Here we discuss the surgical indication and procedure for HT. Thirteen patients with clinically diagnosed Hashimoto's thyroiditis involving a huge diffuse goiter that produced pressure symptoms or nodular lesions were treated with surgery. The gender, age distribution, total dose and period of L-T4 administration prior to the operation, and clinical symptoms caused by the large goiter were evaluated in each case. The titer of antibodies was extremely elevated in 8 HT patients with a diffusely enlarged goiter. The total period of L-T4 medication ranged from 6 to 25 years. A subtotal thyroidectomy in which a small amount of thyroid was left in the posterior area of the bilateral lobes was performed in the 8 cases of diffusely enlarged goiter. Pressure symptoms and the unsightly appearance caused by the goiter were relieved by the surgery in all cases. No surgical complications developed. In conclusion, the surgery is an effective therapy for HT patients who have persistent compression symptoms and/or an unsightly neck appearance due to a large goiter despite long-term L-T4 treatment.