Hashimoto's thyroiditis pathology and risk for thyroid cancer

BACKGROUND

Hashimoto's thyroiditis (HT) has been found to coexist with differentiated thyroid cancer (DTC) in surgical specimens, but an association between the two conditions has been discounted by the medical literature. Therefore, we performed this study to determine any potential relationship between HT and the risk of developing DTC.

METHODS

We collected data for thyrotropin (TSH), thyroxine (T4), thyroid peroxidase antibody (TPO-Ab) titers, surgical pathology, and weight-based levothyroxine (LT4) replacement dose for patients who were referred for thyroid surgery. Patients with HT at final pathology were studied further. To estimate thyroid function, patients with preoperative hypothyroid HT (Hypo-HT) were divided into three equal groups based on their LT4 replacement: LT4-Low (<0.90 μg/kg), LT4-Mid (0.90-1.43 μg/kg), and LT4-High (>1.43 μg/kg). A group of preoperatively euthyroid (Euth-HT) patients but with HT by pathology was also studied. All subjects were also grouped based on their TPO-Ab titer in TPO-high (titer >1:1000) or TPO-low/negative (titer <1:1000 or undetectable) groups. The relationship of HT and DTC was studied extensively.

RESULTS

Of 2811 subjects, 582 had HT on surgical pathology, 365 of whom were Euth-HT preoperatively. DTC was present in 47.9% of the Euth-HT, in 59.7% of LT4-Low, 29.8% of LT4-Mid, and 27.9% of LT4-High groups. The relative risk (RR) for DTC was significantly elevated for the Euth-HT and LT4-Low groups (p<0.001), but not for the LT4-Mid or LT4-High replacement dose groups. TPO-low/negative status conferred an increased RR in the Euth-HT and LT4-Low replacement dose groups (p<0.001 both), while TPO-high status decreased it in Euth-HT group (p<0.05) and made it nonsignificant in the LT4-Low group.

CONCLUSIONS

HT pathology increases the risk for DTC only in euthyroid subjects and those with partially functional thyroid glands (LT4-Low) but not in fully hypothyroid HT (LT4-Mid and LT4-High). High TPO-Ab titers appear to protect against DTC in patients with HT.

Risk of lymph node metastases in multifocal papillary thyroid cancer associated with Hashimoto's thyroiditis

AIMS

The aim of this study was to evaluate the risk factors of lymph nodes metastases (LNM) in patients with papillary thyroid cancer (PTC) and coexisting Hashimoto's thyroiditis (HT).

PATIENTS AND METHODS

This was a retrospective cohort study of patients with PTC and HT who had undergone total thyroidectomy (TT) with central neck dissection (CND) over an 11-year period (between 2002 and 2012). Pathological reports of all eligible patients were reviewed. Multivariable analysis was performed to identify risk factors of LNM.

RESULTS

During the study period, PTC was diagnosed in 130 patients with HT who had undergone TT with CND (F/M ratio = 110:20; median age, 52.4 ± 12.7 years). Multifocal lesions were observed in 28 (21.5 %) patients. LNM were identified in 25 of 28 (89.3 %) patients with multifocal PTC and HT versus 69 of 102 (67.5 %) patients with a solitary focus of PTC and HT (p = 0.023). In multivariable analysis, multifocal disease was identified as an independent risk factor for LNM (odds ratio, 3.99; 95 % confidence interval, 1.12 to 14.15; p = 0.033).

CONCLUSIONS

Multifocal PTC in patients with HT is associated with an increased risk of LNM. Nevertheless, the clinical importance of this finding needs to be validated in well-designed prospective studies.

Coexistence of Histologically Confirmed Hashimoto's Thyroiditis with Different Stages of Papillary Thyroid Carcinoma in a Consecutive Chinese Cohort

Purpose. To determine the relationship between Hashimoto's thyroiditis (HT) and all stages of papillary thyroid carcinoma (PTC) with or without local lymph node metastasis (LNM). Methods. We conducted a retrospective study of thyroidectomies from 2008-2013 in First Affiliated Hospital of Nanjing Medical University. We categorized patients according to the presence of histopathologically proven HT. The prevalence of mPTC (maximum diameter ≤ 10 mm) and crPTC (clinical relevant PTC) and local LNM rates were compared. Results. We evaluated 6,432 consecutive thyroidectomies. In total, 1,328 specimens were confirmed as HT. The prevalence of PTC in this HT cohort was 43.8%, significantly higher than non-HT group. After adjustment of gender and age, the prevalence of PTC was still higher in HT group. HT was a risk factor for PTC in multivariate analysis with odds ratio 2.725 (95% CI, 2.390-3.109) (P < 0.001). However, no correlation was found between HT and LNM of PTC. Conclusion. HT was associated with an increased prevalence of all stages of PTC, independent of tumor size, gender, and age. In contrast, locally advanced disease defined by LNM was unrelated to HT. These data suggest an association of HT with low risk PTC and a potential protective immunologic effect from further disease progression.

Association of Hashimoto's thyroiditis with thyroid cancer

This prospective study investigates the relationship between Hashimoto's thyroiditis (HT) and thyroid cancer (TC) in patients with thyroid nodules (TNs). We prospectively examined 2100 patients with 2753 TNs between January 5, 2010 and August 15, 2013. A total of 2023 patients with 2669 TNs met the inclusion criteria of TN ≥5 mm and age ≥18 years. Each patient had blood drawn before fine-needle aspiration biopsy (FNAB) for the following measurements: TSH, free thyroxine, free tri-iodothyronine, thyroid peroxidase antibody (TPOAb), and antithyroglobulin antibody (TgAb). Diagnosis of TC was based on pathology analysis of thyroidectomy tissue. The associations of TC with the independent variables were determined by univariate and multivariate logistic regression analysis and reported as adjusted odds ratio (OR) with 95% CI. A total of 248 malignant nodules were found in 233 patients. There was an association of TC with both increased serum TgAb concentration and age<45 years. An elevated serum TgAb concentration was found in 10.2% of patients (182 of 1790) with benign nodules as compared with 20.6% of patients (48 of 233) with malignant nodules (P≤0.0001). TgAb (OR=2.24: CI=1.57, 3.19) and TSH ≥1 μIU/ml (OR (95% CI)) OR: 1.49 (1.09, 2.03) were significant predictors of TC in multivariate analysis controlling for age and gender. TC was not associated with serum concentrations of TPOAb. In patients with TN, elevated serum concentration of TgAb and TSH ≥1 μIU/ml are independent predictors for TC. The association between HT and TC is antibody specific.

Precursor lesions of endocrine system neoplasms

The concept of precursor lesions of endocrine neoplasms is a new and interesting topic in endocrine pathology. A variety of clinicopathological conditions are associated with a sequence of cellular changes from hyperplasia to neoplasia; dysplasia is, in contrast, quite rare. The majority of precursor lesions is associated with familial genetic syndromes. These include C-cell hyperplasia in thyroid that is associated with familial medullary thyroid carcinoma, adrenal medullary hyperplasia as a precursor of phaeochromocytomas in MEN2 syndrome, rare pituitary adenohypophyseal cell hyperplasia in familial syndromes associated with pituitary adenomas, MEN1-related precursor gastric enterochromaffin-like cell (ECL) hyperplasia, and duodenal gastrin producing (G) and/or somatostatin producing (D) cell hyperplasia that give rise to type II gastric neuroendocrine tumours (NETs) and duodenal NETs, respectively, and MEN1- or VHL-related islet hyperplasia, islet dysplasia and ductulo-insular complexes that are associated with pancreatic NETs. Other hyperplasias are not thought to be associated with genetic predisposition. Some are attributed to inflammation; autoimmune chronic atrophic gastritis-related ECL hyperplasia can progress to type I gastric NETs, and EC (enterochromaffin) cell or L cell hyperplasia associated with inflammatory bowel diseases can progress to colorectal NETs. In the lung, diffuse idiopathic pulmonary neuroendocrine cell hyperplasia can give rise to peripherally-located low grade pulmonary NETs and tumourlets (neuroendocrine microtumours <5  mm). Rarely, secondary hyperplasias develop into autonomous neoplasms, as in tertiary hyperparathyroidism or pituitary thyrotroph adenomas in primary hypothyroidism. While some precursor lesions, such as thyroid C cell hyperplasia, represent frankly premalignant conditions, others may represent a sequence of proliferative changes from hyperplasia to benign neoplasia that may also progress to malignancy.

Papillary thyroid carcinoma with thyroiditis: lymph node metastasis, complications

Purpose

The aim of this study was to evaluate the clinicopathologic characteristics of papillary thyroid cancer with thyroiditis, and to determine the rate of its complications for it.

Methods

A retrospective review of 1,247 patients with papillary thyroid cancer who underwent primary thyroidectomy was performed. Among them, 316 patients had thyroiditis (group I) while 931 patients had no thyroiditis (group II), as reflected in the final pathologic reports. The two groups' clinicopathologic results and rate of complications were compared.

Results

Female gender, preoperative hypothyroidism, total thyroidectomy, no extrathyroid extension, no lymphovascular invasion, and no perineural invasion were associated with group I. More central lymph nodes were removed in group I than in group II, but there were fewer central lymph nodes with metastasis in group I than in group II. For the lateral lymph nodes, the two groups had the same numbers of removed nodes and nodes with metastatic tumor. Multivariate analysis revealed female predominance, more cases of preoperative hypothyroidism, more dissected lymph nodes, and fewer lymph nodes with metastasis in group I. Among the patients who underwent lobectomy, postoperative hypothyroidism occurred more in group I than in group II (P < 0.001). There was no difference in postoperative complications between the two groups.

Conclusion

Papillary thyroid cancer with thyroiditis showed less aggressive features. Postoperative hypothyroidism occurred more in the patients with thyroiditis.

Thyroid papillary carcinoma associated to Hashimoto's thyroiditis

There is controversy in the literature regarding the association between papillary thyroid carcinoma (PTC) and Hashimoto's thyroiditis (HT) and as to what would be the etiological relationship between them.

Objective

To establish the proportion of cases among patients with TH and CPT, correlating it with histomorphological aspects.

Method

A retrospective study of patients undergoing partial or total thyroidectomy for PTC between 2007 and 2009, a total of 41 cases.

Results

Regarding the association of HT and CPT, we found 11 cases (26.8%), all females, but without statistical significance. The mean age was 44.9 years among the patients with coexistent TH and CPT, whereas it was 49.1 years without that association. The average size of tumors in those without TH was 20.53 mm and for those with TH it was 12.72 mm (p = 0.4). Regarding pathology staging, the ratiosbetween those with and those without TH were kept in T1a, T1b and T3. In T2, there were no cases of coexistence of HT and PTC.

Conclusion

There is a rate of 26.8% of patients with association between TH and CPT, but without differences in relation to tumor size.

Differentiated thyroid cancer is associated with less aggressive disease and better outcome in patients with coexisting Hashimotos thyroiditis

BACKGROUND

Evaluation of surgical specimens suggests that patients with Hashimoto thyroiditis (HT) have a higher prevalence of differentiated thyroid cancer. Although patients with HT are reported to present with earlier stage disease, there is controversy as to whether these patients have better prognosis when adjusted for histology and stage at presentation.

OBJECTIVES

To investigate differences between patients with differentiated thyroid cancer patients and without HT for aggressiveness of disease and clinical outcome, and the decline rate of antithyroglobulin antibodies titers over time.

METHODS

A retrospective study using the Rabin Medical Center Thyroid Cancer Registry. Seven hundred fifty-three patients were included and divided into 2 groups of patients with and without HT at diagnosis. Disease severity at presentation was evaluated using the entire cohort, whereas a control group matched for age, gender, histology, and stage was used to evaluate disease course and outcome.

RESULTS

HT was present in 14.2% (n = 107) of included patients and was associated with smaller primary tumor (17.9 vs 21.2 mm, P = .01) and less lymph node involvement (23% vs 34%, P = .02) at presentation. When matched groups were compared, patients with HT received less additional radioactive iodine (RAI) treatments (1.24 vs 1.45, P = .03) and showed lower rates of persistence at 1 year (13% vs 26%, P = .04) and higher rates of disease remission at the end of follow-up (90% vs 79%, P = .05). On multivariate analysis HT was predictive of a lower rate of lymph nodes involvement (odds ratio 0.34, 95% confidence interval 0.17-0.66) and persistent disease at the end of follow-up (odds ratio 0.48, 95% confidence interval 0.24-0.93). Antithyroglobulin antibodies slowly disappeared in most patients with no evidence of disease.

CONCLUSION

Our study demonstrates that HT is associated with a less aggressive form of differentiated thyroid cancer and a better long-term outcome.

Hashimoto's thyroiditis, microcalcification and raised thyrotropin levels within normal range are associated with thyroid cancer

BACKGROUND

To confirm whether clinical and biochemical parameters or Hashimoto's thyroiditis (HT) could predict the risks of malignancy among subjects who underwent thyroidectomy, as well as to determine the influence of HT on the biological behavior of papillary thyroid cancer (PTC).

METHODS

A total of 2,052 patients who underwent initial thyroidectomy were enrolled between June 2006 and August 2008. Serum free T4, free T3, thyrotropin (TSH), thyroglobulin, thyroglobulin antibody, antimicrosomal antibody, tumor-associated status, and thyroid disorders were documented.

RESULTS

Binary logistic regression analysis was performed to define the risk predictors for thyroid cancer. Finally, calcification, HT, TSH, and age, were entered into the multivariate model. Multivariate logistic regression analysis revealed the risk of thyroid cancer increases in parallel with TSH concentration within normal range, and the risk for malignancy significantly increased with serum TSH 1.97-4.94 mIU/L, compared with TSH less than 0.35 mIU/L (OR = 1.951, 95% CI = 1.201-3.171, P = 0.007). Increased risks of thyroid cancer were also detected among the patients with HT (OR = 3.732, 95% CI = 2.563-5.435), and microcalcification (OR = 14.486, 95% CI = 11.374-18.449). The effects of HT on the aggressiveness of PTC were not observed in extrathyroidal invasion (P = 0.347), capsular infiltration (P = 0.345), angioinvasion (P = 0.512), and lymph node metastases (P = 0.634).

CONCLUSIONS

The risk of malignancy increases in patients with higher level TSH within normal range, as well as the presence of HT and microcalcification. No evidence suggests that coexistent HT alleviates the aggressiveness of PTC.

The association between papillary thyroid carcinoma and histologically proven Hashimoto's thyroiditis: a meta-analysis

OBJECTIVE

No consensus exists on the association between papillary thyroid carcinoma (PTC) and Hashimoto's thyroiditis (HT). To resolve this controversy, this study aimed to evaluate the relationship between the two conditions using a meta-analysis.

METHODS

We searched relevant published studies using citation databases including PubMed, Embase, and ISI Web of Science. The effect sizes of clinicopathologic parameters were calculated by odds ratio (OR), weighted mean difference, or hazard ratio (HR). The effect sizes were combined using a random-effects model.

RESULTS

Thirty-eight eligible studies including 10 648 PTC cases were selected. Histologically proven HT was identified in 2471 (23.2%) PTCs. HT was more frequently observed in PTCs than in benign thyroid diseases and other carcinomas (OR=2.8 and 2.4; P<0.001). PTCs with coexisting HT were significantly related to female patients (OR=2.7; P<0.001), multifocal involvement (OR=1.5; P=0.010), no extrathyroidal extension (OR=1.3; P=0.002), and no lymph node metastasis (OR=1.3; P=0.041). Moreover, PTCs with HT were significantly associated with long recurrence-free survival (HR=0.6; P=0.001).

CONCLUSIONS

Our meta-analysis showed that PTC is significantly associated with pathologically confirmed HT. PTC patients with HT have favorable clinicopathologic characteristics compared with PTCs without HT. However, patients with HT need to be carefully monitored for the development of PTC.

Clinical Review: Hashimoto's thyroiditis and papillary thyroid carcinoma: is there a correlation?

CONTEXT

The link between Hashimoto's thyroiditis (HT) and papillary thyroid cancer (PTC) has long been a topic of controversy. There are conflicting reports; some suggest that these two are positively correlated, whereas other studies report no relationship.

EVIDENCE ACQUISITION

We performed a systematic literature review of original studies that investigated the correlation between HT and PTC. The two main search engines used to identify articles were OVID Medline and PubMed. The included studies were categorized into a fine-needle aspiration biopsy (FNAB) group and an archival thyroidectomy specimen group.

EVIDENCE SYNTHESIS

There is no clear evidence to support the correlation between HT and PTC. Population-based FNAB studies report no linkage, whereas many of the studies of thyroidectomy specimens report a positive relationship. The average prevalence rate of PTC in patients with HT was 1.20% in 8 FNA studies of 18 023 specimens and 27.56% in 8 archival thyroidectomy studies of 9 884 specimens. The relative risk ratio of finding evidence of PTC in HT specimens ranged from .39 to 1.00 in the FNA group (average RR = .69) in contrast to 1.15 to 4.16 from the archival thyroidectomy studies (average RR = 1.59). In addition, there are many studies in the literature that propose a genetic link between HT and PTC involving the PI3K/Akt pathway and RET/PTC gene rearrangements.

CONCLUSION

Although limited by the lack of definitive pathology, population-based FNA studies did not find a statistically significant correlation between HT and PTC. Thyroidectomy studies, which reported a statistically significant positive correlation, are subject to selection bias. More prospective studies with longer follow-up are needed to further elucidate this relationship.

Hashimoto's thyroiditis as a risk factor of papillary thyroid cancer may improve cancer prognosis

OBJECTIVE

Hashimoto's thyroiditis (HT) has been associated with an elevated risk of papillary thyroid cancer (PTC). To investigate the possible influence of HT on the prognosis of PTC patients, we assessed the related clinical factors linking these conditions, especially serum thyroid-stimulating hormone (TSH) concentration.

STUDY DESIGN

Case-control study.

SETTING

The First Hospital of China Medical University.

SUBJECTS AND METHODS

The demographic and histological characteristics of 2478 patients who underwent thyroidectomy at our center from 2004 to 2012 were analyzed.

RESULTS

Compared with patients with benign thyroid nodular disease, patients with PTC showed a significantly higher prevalence of HT (18.8% vs 7.2%, P < .001), mean TSH concentrations (2.02 ± 1.76 vs 1.46 ± 1.21 mIU/L, P < .001), and positivity rates for anti-thyroglobulin antibodies (TGAB; 40.0% vs 20.4%, P < .001) and anti-thyroid peroxidase antibodies (24.8% vs 12.5%, P < .001). These differences remained after excluding all HT patients. The TSH concentrations were significantly higher in PTC patients with HT than in those without HT (2.54 ± 2.06 vs 1.90 ± 1.66 mIU/L, P = .001). Patients with PTC and HT were younger, with a female predominance, and had smaller sized tumors with less advanced TNM stage compared with those without HT, indicating a better prognosis. Multivariate analysis showed that HT, higher TSH concentration, male sex, and TGAB positivity were independent risk factors for PTC development.

CONCLUSION

Histologically confirmed HT is associated with a significantly higher risk of PTC, due primarily to the higher serum TSH concentrations resulting from the tendency to hypothyroidism in HT. Autoimmunity is another independent risk factor for PTC but may be associated with a better prognosis.

The clinical features of papillary thyroid cancer in Hashimoto's thyroiditis patients from an area with a high prevalence of Hashimoto's disease

Background

The goal of this study was to identify the clinicopathological factors of co-existing papillary thyroid cancer (PTC) in patients with Hashimoto’s thyroiditis (HT) and provide information to aid in the diagnosis of such patients.

Methods

This study included 6109 patients treated in a university-based tertiary care cancer hospital over a 3-year period. All of the patients were categorised based on their final diagnosis. Several clinicopathological factors, such as age, gender, nodular size, invasive status, central compartment lymph node metastasis (CLNM) and serum thyroid-stimulating hormone (TSH) level, were compared between the various groups of patients.

Results

There were 653 patients with a final diagnosis of HT. More PTC was found in those with HT (58.3%; 381 of 653) than those without HT (2416 of 5456; 44.3%; p < 0.05). The HT patients with co-occurring PTC were more likely to be younger, be female, have smaller nodules and have higher TSH levels than those without PTC. A multivariate analysis indicated that the presence of HT and higher TSH levels were risk factors for a diagnosis of PTC. In the PTC patients, the presence of HT or another benign nodule was a protective factor for CLNM, whereas no significant association was found for TSH levels.

Conclusion

PTC and HT have a close relationship in this region of highly prevalent HT disease. Based on the results of our study, we hypothesise that long-term HT leads to elevated serum TSH, which is the real risk factor for thyroid cancer.

Diagnostic value of antithyroid peroxidase antibody for incidental autoimmune thyroiditis based on histopathologic results

Detection of antithyroid peroxidase antibody (TPOAb) is widely used in the diagnosis of autoimmune thyroiditis (AIT), but no research has evaluated the diagnostic accuracy of TPOAb detection using histopathologic reference standards. To fill this research gap, this study assessed the diagnostic accuracy of detection of TPOAb and that of other serological markers in asymptomatic patients who had been diagnosed with AIT by histopathologic analysis after thyroid surgery. After review of patient records, 598 patients who had undergone thyroid nodule surgery were enrolled for examination for thyroid parenchyma by a pathologist and classification into no co-existing lymphocytic thyroiditis, Hashimoto thyroiditis, or non-Hashimoto type of lymphocytic thyroiditis (NHLT). The correlation between patient serological data and thyroid parenchyma pathology was analyzed. Statistically significant differences (P < 0.05) were found between co-existing lymphocytic thyroiditis and no co-existing lymphocytic thyroiditis groups regarding thyroid-stimulating hormone (TSH) and TPOAb levels. And, TPOAb titer was significantly associated with the degree of inflammation. An abnormal TPOAb titer was found in 86 of the 598 patients (14.4 %) and the specificity of TPOAb detection for AIT diagnosis was found to be 96.9 %. The prevalence of Hashimoto thyroiditis and NHLT in the 560 papillary thyroid cancer (PTC) patients was found to be 7.9 and 17.9 %, respectively. The results indicate that TPOAb titer is associated with the degree of thyroid inflammation and that detection of TPOAb is a very specific means of diagnosing AIT. The results also indicate that the incidence of AIT and PTC coexistence is relatively high.

Likelihood ratio-based differentiation of nodular Hashimoto thyroiditis and papillary thyroid carcinoma in patients with sonographically evident diffuse hashimoto thyroiditis: preliminary study

OBJECTIVES

To assess the efficacy of sonography for discriminating nodular Hashimoto thyroiditis from papillary thyroid carcinoma in patients with sonographically evident diffuse Hashimoto thyroiditis.

METHODS

This study included 20 patients with 24 surgically confirmed Hashimoto thyroiditis nodules and 40 patients with 40 papillary thyroid carcinoma nodules; all had sonographically evident diffuse Hashimoto thyroiditis. A retrospective review of the sonograms was performed, and significant benign and malignant sonographic features were selected by univariate and multivariate analyses. The combined likelihood ratio was calculated as the product of each feature's likelihood ratio for papillary thyroid carcinoma. We compared the abilities of the original sonographic features and combined likelihood ratios in diagnosing nodular Hashimoto thyroiditis and papillary thyroid carcinoma by their sensitivity, specificity, and Youden index.

RESULTS

The diagnostic capabilities of the sonographic features varied greatly, with Youden indices ranging from 0.175 to 0.700. Compared with single features, combinations of features were unable to improve the Youden indices effectively because the sensitivity and specificity usually changed in opposite directions. For combined likelihood ratios, however, the sensitivity improved greatly without an obvious reduction in specificity, which resulted in the maximum Youden index (0.825). With a combined likelihood ratio greater than 7.00 as the diagnostic criterion for papillary thyroid carcinoma, sensitivity reached 82.5%, whereas specificity remained at 100.0%. With a combined likelihood ratio less than 1.00 for nodular Hashimoto thyroiditis, sensitivity and specificity were 90.0% and 92.5%, respectively.

CONCLUSIONS

Several sonographic features of nodular Hashimoto thyroiditis and papillary thyroid carcinoma in a background of diffuse Hashimoto thyroiditis were significantly different. The combined likelihood ratio may be superior to original sonographic features for discrimination of nodular Hashimoto thyroiditis from papillary thyroid carcinoma; therefore, it is a promising risk index for thyroid nodules and warrants further investigation.

Coexistence of papillary thyroid cancer with Hashimoto thyroiditis

Aims

Conflicting data have been reported with regard to Hashimoto thyroiditis (HT) and risk of malignancy. The aim of this study was to evaluate coexistence of papillary thyroid cancer (PTC) with HT.

Patients and methods

This is a retrospective cohort study in which HT was diagnosed in 452 (F/M ratio = 405:47, median age 53.5 ± 12.1 years) of 7,545 patients qualified for thyroidectomy throughout the years 2002 to 2010. Pathological reports were reviewed to identify prevalence of PTC in HT vs. non-HT patients.

Results

PTC was diagnosed in 106 of 452 (23.5 %) HT patients vs. 530 of 7,093 (7.5 %) non-HT patients (p < 0.001). Metastases to level VI lymph nodes were observed in 81 of 106 (76.4 %) patients with PTC in HT vs. 121 of 530 (22.8 %) patients with PTC in non-HT disease (p < 0.001).

Conclusions

HT was associated with a threefold increase of PTC prevalence as compared to other non-HT thyroid diseases, and the spread of PTC to level VI lymph nodes was four times more frequent in HT than in non-HT patients.

Is thyroidectomy in patients with Hashimoto thyroiditis more risky?

BACKGROUND

Hashimoto thyroiditis (HT) is an organ-specific autoimmune disease characterized by the production of antibodies such as antithyroperoxidase, which leads to the destruction of the thyroid gland and a decrease in normal thyroid function. Thyroidectomy is performed when the patient presents with symptoms or potential neoplastic degeneration occurs; however, surgery can be difficult because of the dense inflammatory process around the thyroid gland. We hypothesized that patients with HT may have a higher rate of complications after thyroid surgery.

METHODS

We identified 1791 consecutive patients who underwent thyroidectomy from May 1994 to December 2009. Patients with HT were compared with those without HT with regard to outcomes with analysis of variance and chi-square test (SPSS, Inc).

RESULTS

Patients with HT were significantly younger and more likely to be female. There was no significant difference between the two groups in the rate of malignancy. However, patients undergoing thyroidectomy with HT had a significantly higher postoperative complication rate. Specifically, the rates of overall, transient, and permanent complications were all increased in HT patients.

CONCLUSION

Patients with HT had a higher rate of complications after thyroidectomy compared with those without HT. Therefore, careful consideration must be taken before pursuing operative treatment in patients with HT including providing adequate informed consent regarding the increased risks of surgery.

Total thyroidectomy for benign thyroid diseases

OBJECTIVE

To review the indications for total thyroidectomy as the preferred option in certain benign diseases of the thyroid in order to prevent recurrence or future reoperations.

METHODS

A retrospective study of patients with benign thyroid diseases, carried out from January 1997 to December 2009, analyzing the data relating to age, surgical treatment and postoperative evolution.

RESULTS

The mean age was 51.8 years (21/77), with the highest incidence in the fifth and sixth decades of life, with 34 (51.5%) patients. The most common preoperative diagnosis was nontoxic multinodular goiter, of which seven were also intrathoracic, followed by autoimmune thyroiditis; recurrent goiter occurred in 11 cases. Multinodular goiter was found in 37 (56.1%) patients, autoimmune thyroiditis in 22 (33.3%), follicular adenoma isolated in five (7.6%), Hurthle cell adenoma in two (3.0%). Sixteen patients (24.2%) had more than one histopathological diagnosis. Permanent injury of the recurrent nerve was observed in one patient (1.5%). There was no case of permanent hypoparathyroidism. There was no operative mortality.

CONCLUSION

Total thyroidectomy is an operation that can be safely performed, with low incidence of permanent complications, which allows one to broaden its indications in various benign thyroid diseases, thus avoiding future recurrences and reoperations.

An elevated level of TSH might be predictive of differentiated thyroid cancer

Suppression therapy of thyreostimulin (TSH) using thyroid hormones improves survival of subjects operated for differentiated thyroid cancer. The TSH level might be different depending on the type of nodule. The objective of this study was to compare retrospectively the TSH level between two groups of subjects who underwent total thyroidectomy for a nodule, matched on sex, ethnicity, age and biological method of TSH measurement, one whose final histology was benign and one malignant. There was no significant difference between the two groups in terms of age, sex, family history of thyroid disease or thyroid autoimmunity. The subjects, whose final histology was malignant, had a mean TSH level significantly higher than subjects with benign disease (1.55 mU/l versus 0.96 mU/l, P=0.003). Cancer risk was greater when the TSH was in the upper tertile of normal range. There was no correlation between the risk of thyroid cancer and age, sex, family history of thyroid disease, or menopausal status. The relative risk of having thyroid carcinoma was higher when the margins of nodules were blurred or in the presence of microcalcifications. These data confirm a trend toward baseline values of TSH higher in subjects with a thyroid-differentiated cancer. However, we could not define a preoperative threshold that would reliably determine the malignant or benign nature of the nodule.

Clinical relationship between Hashimoto's thyroiditis and papillary thyroid cancer

BACKGROUND

The relationship between Hashimoto's thyroiditis (HT) and papillary thyroid cancer (PTC) with regard to their co-occurrence and the effect of concurrent HT on the prognosis of PTC has been debated. The aim of the present study is to determine a clinical relationship between these two disease entities and to evaluate the correlation between concurrent HT and various clinicopathological parameters.

MATERIAL AND METHODS

Demographic and histopathological data were collected from 675 patients undergoing thyroid surgery from 2000 to 2005, and 303 patients who received initial treatment for thyroid disease at our institution and whose medical records were accessible for review were enrolled in this study. Of these participants, 269 with histologically confirmed PTC were analysed according to the presence or absence of concurrent HT.

RESULTS

Of 269 patients with PTC, 21.6% (58/269) had concurrent HT, whereas only 5.9% (2/34) had concurrent HT with another diagnosis (p = 0.031, odds ratio = 4.4; 95% CI, 1.02-18.90). Younger age at presentation and a greater female preponderance were noted in patients with HT compared with those without HT (p = 0.008 and p = 0.009, respectively). Although it was not statistically significant, PTC with HT patients tented to have smaller tumour size (1.6 ± 1.0 cm vs. 1.8 ± 1.5 cm), lower incidence of lymph node metastasis at presentation (12.2% vs. 29.9%), unifocal disease (84.5% vs. 78.7%), and early-stage disease. Additionally, PTC with HT patients exhibited better prognosis, viewed in recurrence and mortality, during the 62-month mean follow-up period.

DISCUSSION

HT was definitely associated with PTC as was chronic inflammation with cancer in other locations. Interestingly, however, the coexistence of HT in PTC cases introduced favourable clinical outcomes compared with those of PTC without HT.

Well-differentiated thyroid carcinoma with concomitant Hashimoto's thyroiditis present with less aggressive clinical stage and low recurrence

Papillary thyroid carcinoma (PTC) and follicular thyroid carcinoma (FTC) are the most common differentiated thyroid cancers. Previous studies report that Hashimoto's thyroiditis (HT) concomitant with PTC is unusual and improves prognosis compared to classical PTC. Few previous studies address FTC concomitant with HT. In this study, we retrospectively analyzed data from one institution and compared clinical presentations and results of treatment of PTC and FTC with and without HT. In addition, studies comparing presentation and long term follow-up prognosis in classical PTC and FTC were conducted. A total of 1,788 PTC patients and 209 FTC patients underwent thyroidectomy with or without lymph node dissection and follow-up at Chang Gung Medical Center in Linkou, Taiwan. All thyroid carcinomas were pathologically classified according to World Health Organization criteria. Histological patterns of PTC were categorized as classical PTC, or PTC with HT. Follicular thyroid carcinoma patients were categorized as FTC or FTC with HT. The dataset contained a total of 1,703 PTC cases categorized as classical PTC, 85 cases of PTC with HT, 201 cases of FTC and eight cases of FTC with HT. Analysis of Classification of Malignant Tumors (TNM) stage revealed a higher percentage of classical PTC in stage IV than HT group (12.03% vs. 4.70%). Mean tumor size of classical PTC was larger than HT group. Although 42.3% of FTC cases presented with distant metastases, no cases of FTC with HT presented with distant metastasis. Cancer-specific mortality was higher in classical PTC group than in PTC with HT. There was 53.2% of FTC without HT assigned recurrent status, and six of them died of thyroid cancer. No cancer mortality or recurrence in HT with FTC. PTC and FTC with HT presented with better clinical stage and better prognosis after same therapeutic modality. In conclusions, both PTC and FTC with HT have less aggressive clinical presentation and better prognosis.

Preoperative serum thyroid stimulating hormone levels in well-differentiated thyroid carcinoma is a predictive factor for lateral lymph node metastasis as well as extrathyroidal extension in Korean patients: a single-center experience

It has been known that thyroid stimulating hormone (TSH) stimulates the growth or development of thyroid malignancy and higher serum TSH has association with both thyroid cancer incidence and advanced tumor stage. However, the role of TSH in high-risk features of well-differentiated thyroid cancer was not fully evaluated especially in Asian population. The purpose of our study is to evaluate the association of preoperative serum TSH levels with the advance of differentiated thyroid cancer and its high-risk clinicopathological features in Korean patients. We evaluated 554 patients retrospectively who underwent thyroidectomy and diagnosed as differentiated thyroid cancer during a 3-year period at Pusan National University Hospital. The preoperative TSH levels were significantly higher in the patients with extrathyroidal extension (P = 0.002) and those with lateral lymph node metastasis (P = 0.007). As the increase of the serum TSH concentration, there were significant rising trends in the prevalence of extrathyroidal extension (P = 0.009). In the patients with TSH ≥ 2.5 mIU/L, the prevalences of extrathyroidal extension (P = 0.006) and lateral lymph node metastasis (P = 0.024) were also significantly higher. Using multiple logistic regression, preoperative TSH level was a predictive factor for the presence of extrathyroidal extension (P = 0.008) and lateral lymph node metastasis (P = 0.025). Hashimoto's thyroiditis itself was not associated with the status of extrathyroidal extension and lateral lymph node metastasis. In conclusion, preoperative TSH levels were associated with lateral lymph node matastasis, a novel finding, and extrathyroidal extension in well differentiated thyroid cancer and might be useful as a preoperative supplementary marker for determining the optimal extent of differentiated thyroid cancer surgery in Korean patients.

Should patients with symptomatic Hashimoto's thyroiditis pursue surgery?

BACKGROUND

In this study, patients with Hashimoto's Thyroiditis and significant symptoms were evaluated for improvement or resolution of preoperative symptoms after thyroidectomy. Hashimoto's thyroiditis (HT) is an organ-specific autoimmune disease characterized by production of antibodies such as anti-thyroperoxidase (TPO), which leads to destruction of the thyroid gland and a decrease in normal thyroid function. Thyroidectomy is not generally recommended because the dense inflammatory process that surrounds the thyroid gland can make resection more difficult. However, patients with HT are considered for surgery if they experience persistent symptoms after conservative therapy. We hypothesized that patients with HT and significant compressive and other associated symptoms may benefit from thyroidectomy for palliation.

METHODS

We identified 1791 patients who underwent thyroidectomy from May 1994 to December 2009. Of those 1791 patients, 311 were diagnosed with HT. Of these 311 patients, 133 had 170 significant preoperative symptoms, and served as our sample population. Patients were subjectively evaluated for improvement or relief of symptoms postoperatively.

RESULTS

The mean age of the group was 46 ± 1 y, and 90% were female. Patients underwent lobectomy (33%), subtotal thyroidectomy (6%), or total thyroidectomy (61%). The overall rate of symptomatic improvement for HT patients was 90% after thyroidectomy. The most frequent preoperative symptom was compression, and >93% of patients experienced relief. In addition, we found high rates of improvement for HT patients with other preoperative symptoms including voice problems (77%), hormone imbalance (84%), and other (90%).

CONCLUSION

The overwhelming majority of HT patients with significant symptoms appear to benefit from thyroidectomy. Therefore, HT patients should consider pursuing surgery for palliation if they suffer from persistent symptoms after conservative therapy.

The association between thyroid carcinoma and Hashimoto's thyroiditis: the ultrasonographic and histopathologic characteristics of malignant nodules

BACKGROUND

Some but not all reports, particularly those of a retrospective nature, have noted an increased risk of carcinoma in thyroid nodules in patients with Hashimoto's thyroiditis (HT). Thyroid cancer (TC) in patients with HT, however, have been reported to have a better prognosis. In the presence of HT, the ultrasonography (US) appearance of the thyroid gland might vary greatly, making it more difficult to differentiate between benign and malignant nodules. The aim of this study was to determine if there is an association between TC and HT and to determine if the US and histopathologic characteristics of malignant nodules in patients with and without HT are similar.

METHODS

Six hundred thirteen patients who underwent total thyroidectomy between 2005 and 2008 for nodular goiter were included in this study. The preoperative US characteristics and postoperative histopathologic features in patients with and without HT were compared. The diagnosis of HT was based on histopathologic features.

RESULTS

Ninety-two patients had HT. The prevalence of TC in the HT patients was 45.7%. In contrast, it was 29% in patients without HT (p = 0.001). The prevalence of HT in the patients with TC was 21.8% and in patients without TC was 11.9% (p = 0.001). The rate of incidental TC, defined as TC identified during surgery or following histopathologic examination of permanent sections despite preoperative benign cytology results, was higher in patients with HT (33.3%) than in those without (13.0%) HT (p = 0.004). The US characteristics of papillary thyroid carcinoma, which included number of nodules, echogenity, echoic texture, microcalcifications, macrocalcifications, halo sign, and regularity of margins, were similar in the group with HT compared with the group without HT. When the histopathologic characteristics of papillary thyroid carcinoma in patients with and without HT were compared, again there was no significant difference.

CONCLUSIONS

We suggest that there is an association between HT and TC, and HT may predispose to the development of TC. This indicates the need for close observation of neoplastic changes in patients with HT. Nevertheless, the presence of HT seems to have no effect on the US and histopathologic characteristics of malignant nodules in TC patients. This finding may indicate that evaluation of nodules and initial treatment of TC in these patients does not require different management.

Hashimoto's thyroiditis is not associated with increased risk of thyroid cancer in patients with thyroid nodules: a single-center prospective study

BACKGROUND

The risk of thyroid carcinoma in patients with thyroid nodules associated with Hashimoto's thyroiditis (HT) is a debatable issue. The studies defining the true risk of thyroid malignancy are scanty and mainly depend on retrospective series. To eliminate inherent bias of retrospective studies, this prospective study was carried out to evaluate the true malignancy rate of unselected thyroid nodules in patients with HT who underwent fine-needle aspiration cytology (FNAC).

METHODS

These prospective data were gathered on all patients newly diagnosed with thyroid nodules who were sent for FNAC between May 2006 and August 2009. All patients were evaluated for the presence of HT diagnosis by measuring thyroid autoantibodies. If a patient had at least one positive thyroid autoantibody, then the patient was defined as HT with thyroid nodules. There were 164 patients (147 women and 17 men) with thyroid nodules associated with HT (HT group). There were 551 patients (432 women and 119 men) with thyroid nodules without HT (control group). All patients underwent FNAC and ultrasonography (US).

RESULTS

The malignancy rate was 1.0% in HT group (2 out of 191 nodules) and 2.7% in the control group (19 out of 713 nodules), a not significant (p = 0.19) difference. In the two cytologically malignant nodules in HT group and 19 in the control group, papillary thyroid carcinoma was diagnosed after thyroidectomy and histopathological examination. US features of nodule echogenicity, structure, margin, and Doppler flow were similar between the two groups. US features of microcalcification and absence of peripheral halo were more prominent in the nodules of the control group (p = 0.002 and p < 0.001, respectively).

CONCLUSIONS

On the basis of cytopathological criteria, thyroid nodules in patients with HT are no more likely to be malignant than in those without HT. Many of the US features of benign thyroid nodules are similar in patients with and patients without HT.

Sonography and fine-needle aspiration biopsy in the diagnosis of benign versus malignant nodules in patients with autoimmune thyroiditis

PURPOSE

To correlate sonographic (US) characteristics and results of fine-needle aspiration biopsy (FNAB) of thyroid nodules in autoimmune thyroiditis (AT) with surgical pathological findings.

METHOD

Forty AT patients with 40 nodular lesions were analyzed retrospectively. Five sonographic characteristics were recorded for each nodule: diameter, echogenicity, microcalcification, halo sign, and margin. Preoperative sonograms and FNAB results were compared with postoperative histopathological findings.

RESULT

Twenty-four of the 40 nodules were malignant, including 20 papillary carcinomas, 3 follicular carcinomas, and 1 medullary carcinoma. Of the 16 benign nodules, 8 were nodular hyperplasia, 6 lymphocytic thyroiditis, and 1 each follicular adenoma and Hürthle cell adenoma. The only US parameter that was significant in malignant vs. benign nodules was the presence of poorly defined margins. Based on preoperative cytology, 22 of the 23 malignant nodules were correctly diagnosed, and 10 of the 14 benign nodules were correctly identified. The positive predictive value was 78.6%, and the negative predictive value was 93.7%.

CONCLUSION

No single US parameter can predict thyroid malignancy in patients with AT. A combination of US and FNAB provides the most sensitive and specific approach available preoperatively.

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.

The incidence of cancer and rate of false-negative cytology in thyroid nodules greater than or equal to 4 cm in size

BACKGROUND

High false-negative rates for fine needle aspiration biopsy (FNAB) of thyroid nodules greater than 3 cm have prompted recommendations for diagnostic lobectomy. We considered the presence of a greater than 4 cm nodule an independent indication for thyroidectomy regardless of FNAB results.

METHODS

We reviewed clinical data from 223 patients with thyroid nodules greater than or equal to 4 cm operated on from July 2003 to November 2006. Unifocal micropapillary cancer was considered clinically insignificant.

RESULTS

Clinically significant thyroid cancer was frequent, occurring in 57 of 223 patients (26%). Subgroup analysis showed that 43 of 223 patients (19.3%) had carcinoma within the mass and that 7 of 223 patients (3.1%) had significant carcinoma elsewhere in the resected thyroid. Multifocal micropapillary cancer was found in an additional 7 of 223 patients (3.1%). Preoperative FNAB was read incorrectly as benign in 9 of 71 patients with cancer (13%) (16% including multifocal micropapillary carcinoma). Benign FNAB results failed to identify 24 (34%) follicular lesions (including 7 cancers). In patients with preoperative FNAB results categorized as indeterminate lesions, 17 of 43 patients (40%) had carcinoma of the mass on final pathology.

CONCLUSIONS

In thyroid nodules greater than or equal to 4 cm, the incidence of carcinoma is high with a high false-negative rate for preoperative benign cytology. Thyroid nodules greater than or equal to 4 cm should be considered for diagnostic lobectomy regardless of FNAB results.

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.

High frequency of level II-V lymph node involvement in RET/PTC positive papillary thyroid carcinoma

AIMS

To investigate the frequency and clinical significance of RET rearrangement in Chinese patients with papillary thyroid carcinoma (PTC) and discuss the role of RET rearrangement in therapeutic decision-making after the performance of level VI lymph node dissection and the 2002 AJCC staging system.

METHODS

RET/PTC-1 and RET/PTC-3 were detected in 126 PTCs using reverse transcription-polymerase chain reaction (RT-PCR) and direct sequencing.

RESULTS

RET rearrangement was detected in 18 cases of PTC. The patient group aged < 20 years had the highest frequency (3/6) of RET rearrangement among the age groups (< 20 years, 20-40 years and > or = 40 years; P=0.03). RET/PTC-1 positive patients were more likely to suffer from Hashimoto's thyroiditis simultaneously (P=0.02) while RET/PTC-3 positive patients had a higher frequency of extrathyroidal extension (P<0.01) and advanced T classification (P<0.01). RET rearrangement (OR=8.70, 95% CI 1.69-44.81), male (OR=3.88, 95% CI 1.41-10.69), age (OR=0.96, 95% CI 0.93-0.99), multifocality (OR=3.54, 95% CI 1.33-9.41) and advanced T classification (OR=7.32, 95% CI 2.91-18.40) were all identified as risk factors of level II-V lymph node involvement in the multivariate analysis.

CONCLUSIONS

The frequency of RET rearrangement in Chinese patients is low and age related. RET/PTC-1 and RET/PTC-3 are associated with different clinical pathological characteristics but not with lymph node involvement. The RET/PTC positive patients should receive more attention to lateral neck in the management of PTC.

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.