IgG4-related disease of the thyroid glands

Recent reports on Hashimoto's thyroiditis (HT) with increased numbers of IgG4-positive plasma cells suggest that this type of HT may have a close relationship to IgG4-related disease (IgG4-RD). This unique subgroup of HT is termed as IgG4 thyroiditis and reveals distinct clinical, serological, and sonographic features from the non-IgG4 thyroiditis group. On the basis of immunostaining for IgG4, HT was divided into an IgG4 thyroiditis group and a non-IgG4 thyroiditis group. Clinically, IgG4 thyroiditis was associated with younger age group, lower female-male ratio, higher levels of thyroid autoantibodies, diffuse low echogenicity, more rapid progress requiring surgical treatment and more subclinical hypothyroidism. Serum IgG4 concentrations elevated in IgG4 thyroiditis and decreased significantly after a thyroidectomy. Histopathologically, IgG4 thyroiditis showed a higher grade of stromal fibrosis, lymphoplasmacytic infiltration, and follicular cell degeneration than non-IgG4 thyroiditis. IgG4 thyroiditis may represent IgG4-RD of thyroid gland, because it shares common histopathological characteristics with IgG4-RD in other organs. The identification of IgG4-RD of the thyroid gland opens new insights not only for patient's treatment with HT but also for the development of new therapeutic approaches for this rapidly progressive destructive subtype of HT. This article mainly focuses on reviewing the unique histopathological, clinical, and serological features of IgG4 thyroiditis group of HT. The etiology and genetic changes of HT are also discussed.

Transcriptional activity of the 5'-flanking region of the thyroid transcription factor-1 gene in human thyroid cell lines

Thyroid transcription factor-1 (TTF-1, NKX2-1) is a homeodomain-containing transcriptional factor that binds to and activates the promoters of thyroid and lung-specific genes, such as thyroglobulin, thyroid peroxidase, and thyroid stimulating hormone receptor. TTF-1 is known to play a key role in the development of the thyroid. However, the precise mechanism of TTF-1 gene transcription in human thyroid cells has not been studied. The expression of transcriptional activity in various lengths of the 5'-flanking region of the human TTF -1 gene was studied in TTF-1 positive and negative human thyroid cell lines. Increased transcriptional activity was observed in thyroid cell lines containing plasmids that coded for a sequence proximal to the transcription start site of exon 1 of the TTF-1 gene. However, we did not observe any difference in promoter activity in the region up to -2.6 kb from the proximal transcription start site of the TTF-1 gene between TTF-1 positive and negative cells. These results suggest that the proximal 5'-flanking region of the human TTF -1 gene does not contain sufficient cis-active regulatory information to direct gene expression in thyroid cells, and that other cis- or trans-acting factors participate in the thyroid specific gene expression of TTF-1.

Effects of fission neutrons on human thyroid tissues maintained in SCID mice

Morphology and function (secretion of thyroid hormone) of human thyroid tissues from Graves' disease patients are well maintained in C57BL/6J-scid mice. Serum level of thyroid hormone was reduced by fission neutrons from the nuclear reactor UTR-KINKI, and changes in thyroid hormone by fission neutrons were bigger than those by low LET radiations, X-rays and (137)Cs gamma-rays, suggesting high relative biological effectiveness (RBE; 6.5) of fission neutrons. Microarray analyses revealed that about 3% of genes showed more than 4-fold change in gene expression in the unexposed thyroid tissues against surgically resected thyroid tissues from the same patient, probably due to the difficult oxygen and nutrient supply shortly after transplantation. Dose-dependent changes in gene expression against unexposed concurrent controls were observed with increasing doses of fission neutrons (0.2-0.6Gy) and (137)Cs gamma-rays (1.0-3.0Gy) and showed high RBE (4.2). Furthermore, there were some specific genes which showed more than 4-fold change in gene expression in all the thyroid tissues exposed to higher doses of radiation, especially neutrons (0.4 and 0.6Gy), but none at lower doses (0.2Gy of neutrons and 1.0 and 2.0Gy of gamma-rays). These genes related to degeneration, regeneration, apoptosis, and transcription, respond specifically and very sensitively to neutron injury in human thyroid tissues. This is the first experimental report that fission neutrons can induce some morphological and functional disorders in human tissues, showing high RBE against gamma-ray exposure. These results are useful to evaluate the risks of fission neutrons and cosmic rays to humans.

Induction chemotherapy with weekly paclitaxel administration for anaplastic thyroid carcinoma

BACKGROUND

Anaplastic thyroid carcinoma (ATC) has a very dire prognosis and no effective therapeutic strategies have been established for ATC patients, especially those with stage IVB or IVC. Our objective was to investigate the effectiveness of weekly paclitaxel administered as induction chemotherapy and to establish novel therapeutic strategies for ATC.

METHODS

We performed induction chemotherapy by weekly paclitaxel administration for patients with stage IVB (nine patients) and IVC (four patients) disease. Clinical and histological responses were assessed. Overall survival was compared with that of ATC patients with stage IVB (n = 50) and IVC (n = 13) treated without paclitaxel.

RESULTS

One patient demonstrated complete response (CR) and two demonstrated partial response (PR) in the stage IVB group (response rate: 33%), and one patient showed PR in stage IVC (response rate: 25%). Curative surgery and adjuvant therapy were performed for four patients with stage IVB, and 32 months after treatment, all the four are alive and free of disease. One CR patient and one stable disease patient were assessed as grade IV (complete remission) and grade III (nearly CR) on histological response, respectively. All four patients with stage IVC died of carcinoma within 8 months. Overall survival of stage IVB patients with induction chemotherapy was better (p = 0.0213) than that without the chemotherapy and also better (p = 0.0467) than those with chemotherapy other than paclitaxel. However, induction chemotherapy did not improve the overall survival of stage IVC patients (p = 0.2002).

CONCLUSIONS

Induction chemotherapy by weekly paclitaxel is a promising therapeutic strategy for stage IVB ATC patients. Responders can be expected to achieve long-term survival. We could not get significant difference of overall survival between stage IVC patients with or without weekly induction paclitaxel, although there were some cases that responded well.

S100A8 and S100A9 expression is a crucial factor for dedifferentiation in thyroid carcinoma

BACKGROUND

S100A8 plays a role in various functions of myeloid cells by forming a heterocomplex with S100A9. S100A8 and S100A9 are also known to be overexpressed in certain species of carcinomas.

MATERIALS AND METHODS

In this study, the protein expression of S100A8 as well as that of S100A9 was investigated in thyroid tumors.

RESULTS

All of the undifferentiated carcinomas were immunopositive for S100A8 and S100A9 and overlap between staining patterns of both proteins was observed. In poorly differentiated carcinomas, all the cases were negative for S100A8, while slight immunopositivity of S100A9 was seen in 2 cases. Papillary carcinoma, follicular carcinoma, follicular adenoma and medullary carcinoma and normal follicules were negative for both proteins.

CONCLUSION

S100A8 plays an important role in dedifferentiation of thyroid carcinoma possibly by forming a complex with S100A9.

Investigation of the validity of UICC stage grouping of anaplastic carcinoma of the thyroid

OBJECTIVE

Anaplastic thyroid carcinoma arises from differentiated carcinoma and has a very aggressive character. In this study, we investigated the prognosis of patients with anaplastic carcinoma based on UICC stage.

PATIENTS AND METHODS

We investigated the prognosis of 75 patients who were diagnosed as having anaplastic carcinoma at Kuma Hospital between 1983 and 2006. Of these patients, 14, 49 and 12 were classified into Stages IVA, IVB, and IVC respectively.

RESULTS

Stage IVA patients showed a significantly better prognosis than Stage IVB or IVC patients (p = 0.0017). All patients with Stage IVC died of carcinoma within 1 year regardless of whether locally complete resection was performed. Prognosis of Stage IVB patients who underwent curative surgery did not differ from that of Stage IVA patients, but the prognosis of those who did not undergo surgery or only received palliative surgery was as poor as that of Stage IVC patients.

CONCLUSIONS

Extensive surgical treatment is recommended for Stage IVA patients and palliative care is appropriate for Stage IVC patients. For Stage IVB patients, surgical treatment as a primary therapy is appropriate only when curative resection of the tumour is expected.

Exacerbation of thyroid associated ophthalmopathy after arterial embolization therapy in a patient with Graves' disease

A novel treatment approach to Graves' disease (GD), embolization of the thyroid gland arteries, is evaluated with respect to its indications and adverse effects. We describe an exacerbation of thyroid associated ophthalmopathy (TAO) following thyroid artery embolization in a woman with GD and mild stable TAO (NOSPECS classification, class I grade a). A 45-year-old woman with GD and inactive TAO, in whom thyroid function was stable following blockade of hormone release combined with replacement therapy, underwent embolization of three thyroid arteries. Initially, there were neither adverse effects nor complications; however, the patient developed severe TAO (NOSPECS classification, class IV grade b) 3 months after the arterial embolization. Steroid pulse treatments followed by total thyroidectomy resulted in improvement of the eye signs and symptoms. The clinical course and the serial changes of the thyroglobulin and thyroglobulin-antibody titers suggested that the destruction of thyroid follicles, induced by the arterial embolization, triggered the exacerbation of her TAO. Our experience argues for the use of caution when arterial embolization is considered for GD patients with even the mildest TAO (NOSPECS classification, class I).

Expression of nestin mRNA is a differentiation marker in thyroid tumors

Nestin is a maker that identifies stem cells in some adult tissues, and its expression is believed to relate to malignancy in cancer cells. In this study, we measured the expression levels of nestin mRNA in various kinds of thyroid tumor by the real-time quantitative reverse transcription-polymerase chain reaction. Unexpectedly, nestin mRNA was detected in almost all differentiated thyroid tumors and normal thyroid tissues, whereas extremely decreased expression was observed in anaplastic carcinomas, which are the most malignant of the thyroid follicular cell-derived tumors. These results suggest that nestin mRNA is a differentiation marker, and its expression does not relate to malignant characteristics in thyroid tumors.

Clinical significance of extrathyroid extension to the parathyroid gland of papillary thyroid carcinoma

Extrathyroid extension is a prominent prognostic factor of papillary thyroid carcinoma (PTC). In the UICC TNM classification, minimal extension to the sternothyroid muscle and perithyroid soft tissue is classified as T3 and further massive extension is classified as T4, the highest T grade. However, there have been few studies on the clinical significance of extension to the parathyroid gland in a large case series. In this study, we investigated the prognosis of PTC with extension to the parathyroid gland in a series of 3208 patients who underwent initial surgery between 1997 and 2004. Of these patients, 51 (1.6%) showed extension to the parathyroid gland on pathological examination. Twenty-one of these patients had massive extrathyroid extension to other adjacent organs corresponding to pT4. The remaining 30 were enrolled in this study. The disease-free survival (DFS) of these 30 patients was significantly better (p<0.0001) than that of pT4 patients and did not differ from that of patients showing minimal extrathyroid extension without extension to the parathyroid gland (p = 0.6264). Furthermore, none of these 30 patients died of carcinoma. Taken together, it is appropriate that extension to the parathyroid gland of PTC is graded as minimal extrathyroid extension (pT3), but not massive extension (pT4). Since minimal extension did not affect patient prognosis in our series, it is suggested that extension to the parathyroid gland has little clinical significance in PTC.

BRAF mutation in papillary thyroid carcinoma in a Japanese population: its lack of correlation with high-risk clinicopathological features and disease-free survival of patients

Recent studies have demonstrated that BRAF(V600E) mutation is a common event in papillary thyroid carcinoma and a majority of these lesions have shown a direct relationship between BRAF(V600E) mutation and aggressive characteristics, including a worse patient prognosis. However, there are no studies from Japan regarding this issue in a large series with adequate postoperative follow-up periods. We investigated BRAF(V600E) mutation in 631 patients with papillary carcinoma having median follow-up periods of 83 months. The prevalence of BRAF(V600E) mutation was 38.4%, and the rate was higher in carcinoma larger than 1.0 cm but did not successively increase with tumor size. Furthermore, the prevalence did not significantly increase in cases demonstrating high-risk biological features such as clinically apparent lymph node metastasis, massive extrathyroid extension, advanced age, distant metastasis at surgery, and advanced Stage. The disease-free survival of patients with BRAF(V600E) mutation did not differ from that of those without BRAF(V600E) mutation. These findings indicate that, although BRAF(V600E) mutation may play some roles in local carcinoma development, there is no evidence that BRAF(V600E) mutation significantly reflects the aggressive characteristics and poor prognosis of patients with papillary carcinoma in Japan.

Preoperative administration of excess iodide increases thyroid volume of patients with Graves' disease

Preoperative excess iodide administration for patients with Graves' disease has been widely adopted by surgeons to perform surgery safely, because it decreases blood flow in the thyroid. However, surgeons often encounter the enlargement of thyroid volume after iodide administration, which makes surgery even more difficult. In this study, we retrospectively investigated the change in thyroid volume in Graves' disease that was evaluated on ultrasonography between before and after iodide administration. Eighty-nine patients who received iodide administered (KI(+) patients) and 24 in whom iodide was not administrated (KI(-) patients) before surgery for Graves' disease were enrolled in the study. The level of free T4 (FT4) significantly decreased and that of thyroid stimulating hormone (TSH) significantly increased after iodide administration. Average thyroid volume also significantly increased for KI(+) patients after iodide administration and 17% of these patients showed a 30% or more increase in thyroid volume. In KI(-) patients who were preoperatively treated only by anti-thyroid drugs, thyroid volume did not change before surgery. Preoperative TSH levels remained below measurement sensitivity in 37 of KI(+) patients, but the average thyroid volume also significantly increased after iodide administration. These findings suggest that thyroid volume in Graves' disease can increase with iodide administration not only due to TSH stimulation but also due to reasons other than TSH. Surgeons should be careful when preoperatively iodide administering to patients with Graves' disease, especially when the goiter is large.

Prognosis of patients with papillary thyroid carcinoma having clinically apparent metastasis to the lateral compartment

Lymph node metastasis is an important clinicopathological feature of papillary thyroid carcinoma (PTC). PTC having clinically apparent lateral node metastasis detectable on preoperative imaging studies (N1b) is known to show a dire prognosis. However, N1b cases include various levels of biological aggressiveness, depending on the size, number, laterality and invasiveness of metastatic nodes. We investigated differences in the prognoses of 621 N1b patients based on these features and compared their prognoses with those of 4297 patients without clinically apparent metastasis (N0) and 125 patients with clinically apparent central node metastasis only (N1a). Disease-free survival (DFS) and cause-specific survival (CSS) of N1b or N1a patients were significantly worse than those of N0 patients, but the prognosis of N1b patients did not differ from that of N1a patients. In the subset of N1b patients, metastatic nodes larger than 3cm, extranodal extension, or 5 or more clinically apparent metastatic nodes independently affected DFS and a combination of the former two features also showed an effect on CSS on multivariate analysis. Prognosis of N1b patients who had none of these features did not differ from that of N1a patients. It is therefore suggested that N1b patients having metastasis larger than 3cm, those showing extranodal extension, and those having 5 or more clinically apparent metastasis should regarded as high-risk, and that careful surgical treatment and postoperative follow-up are necessary.

Prognosis of patients with papillary carcinoma showing anaplastic transformation in regional lymph nodes that were curatively resected

Anaplastic carcinoma arises from differentiated carcinoma and generally shows a dire prognosis. Anaplastic transformation may occur not only in primary tumors but also in metastatic lymph nodes. We encountered 5 cases of papillary carcinoma showing anaplastic transformation in lymph nodes that were curatively resected. Patient ages ranged from 67 to 85 years. Two of these patients showed anaplastic transformation at the initial surgery and the remaining 3 showed anaplastic transformation after repeated recurrence to the lymph nodes. After resection of anaplastic lesions of the nodes, 2 patients underwent radiation therapy, whereas the remaining 3 did not receive any adjuvant therapy. One patient died of rapid growth of lung metastasis 5 months after the resection. One patient died of carcinoma 63 months after surgery. Two patients have survived to date, 6 and 85 months after resection, respectively. The remaining one patient died of heart failure 11 months after surgery. It is therefore suggested that long-term survival can be expected for patients with differentiated carcinoma showing anaplastic transformation in the lymph node if the lesions can be curatively resected.

Prevalence and biological behaviour of variants of papillary thyroid carcinoma: experience at a single institute

AIMS

There are many variants of papillary carcinoma, and some of these variants have been reported to show biological behaviours differing from that of conventional papillary carcinoma. In this study, we present our experience regarding the prevalence and prognoses of these variants of papillary carcinoma.

METHODS

H&E sections from 1521 patients who underwent initial surgery for papillary carcinoma in Kuma Hospital between 1987 and 1995 were re-reviewed and classified into conventional papillary carcinoma and various histological variants. We investigated the biological behaviours of these lesions, including prognoses.

RESULTS

Follicular, tall cell and oncocytic variants were observed in comparably high incidences: 6.6%, 3.9%, and 1.9%, respectively. Patients with tall cell variant showed significantly worse disease-free survival (DFS) and cause-specific survival (CSS) rates than those with conventional papillary carcinoma. The prognoses of patients with follicular variant did not differ from those of patients with conventional papillary carcinoma. Patients with oncocytic variant have not shown carcinoma recurrence. Among the rare variants, which accounted for less than 1%, columnar cell carcinoma showed a worse prognosis.

CONCLUSIONS

Since patients with some variants show different clinical outcomes from those with conventional papillary carcinoma, classification of variants might be helpful to predict patient prognosis.

Prevalence and prognosis of familial follicular thyroid carcinoma

Although the responsible gene has not yet been identified, patients with differentiated thyroid carcinoma, including papillary and follicular carcinomas, demonstrating a family history have been reported and patients having one or more family members with differentiated carcinoma among their first-degree relatives are designated as having familial nonmedullary thyroid carcinoma (FNMTC). In this study, we investigated the biological characteristics, including prognosis, of familial follicular carcinoma. Three hundred and nineteen patients who underwent initial surgery for follicular thyroid carcinoma between 1987 and 2004 who were enrolled in this study. Of these 319 patients, 6 patients (1.9%) in 6 families were classified as having familial follicular carcinoma based on the criteria described above. The incidence of aggressive characteristics such as male gender, age 45 years or older, poor differentiation, widely invasive carcinoma, tumor larger than 4 cm and distant metastasis at diagnosis did not differ between familial and sporadic follicular carcinomas. One patient with familial follicular carcinoma underwent re-operation because of newly detected papillary carcinoma in the remnant thyroid 160 months after the initial surgery, but none of the 6 patients with familial carcinoma showed recurrence or died of follicular carcinoma. We can therefore conclude that FMNTC of the follicular type is very rare and there is no evidence that familial follicular carcinoma is more aggressive or has a worse prognosis than sporadic follicular carcinoma. The therapeutic strategy for follicular carcinoma might depend on conventional prognostic factors such as poor differentiation and distant metastasis at diagnosis, but not on whether the carcinoma is familial or sporadic.

Distant and lymph node metastases of thyroid nodules with no pathological evidence of malignancy: a limitation of pathological examination

Among thyroid nodules arising from follicular cells, benign nodular goiter is thought not to metastasize to regional or distant organs. However, we encountered five cases that were pathologically diagnosed as benign nodular goiter but showed metastasis. The prevalence of benign nodular goiter showing metastasis was 0.17% (5 of 2978 patients). On pathology, there were no detectable signs of carcinoma or follicular adenoma lesions. Two patients showed lymph node metastasis that was pathologically confirmed as metastasis of nodular goiter. One was preoperatively and another was postoperatively detected by ultrasonography. These patients also showed distant metastases that could be ablated by radioiodine. One patient preoperatively showed lung metastasis and the remaining two showed lung and bone metastases and bone metastasis postoperatively. Pathological diagnosis of thyroid nodules has limitations, and cases diagnosed as benign nodular goiter should still undergo careful follow-up.

Increased expression levels of tensin3 mRNA in thyroid functional adenomas as compared to non-functioning adenomas

Tensin3 is a member of tensin family which is localized in focal adhesion. In our previous study, a high level of tensin3 mRNA expression was observed in the thyroid but not in other tissues, thus, tensin3 gene was regarded as a novel thyroid-specific gene. The high expression level of tensin3 mRNA in normal thyroid tissue suggests some fundamental roles in thyroid functions. In fact, the expression level of tensin3 mRNA was low in most thyroid carcinomas and non-functioning thyroid follicular adenomas which do not produce thyroid hormone. In the present study, we measured the expression levels of tensin3 mRNA in twelve functional adenomas and compared the results with those in normal thyroid tissues, adenomatous goiters and non-functioning thyroid follicular adenomas. Tensin3 mRNA was expressed abundantly in all twelve functional adenomas at almost the same level as in normal thyroid tissues and adenomatous goiters, while its expression was significantly lower in non-functioning follicular adenomas. Considering these facts, an abundant expression of tensin3 mRNA is observed in tissues that produce thyroid hormone, which suggests some fundamental roles in basic thyroid functions.

3,5,3'-Triiodothyronine thyrotoxicosis due to increased conversion of administered levothyroxine in patients with massive metastatic follicular thyroid carcinoma

OBJECTIVE

Some patients with massive metastatic thyroid carcinoma exhibit T(3) thyrotoxicosis. We investigated the prevalence and cause of T(3) thyrotoxicosis and the clues to the diagnosis.

DESIGN

Serum free T(3) (FT(3)), free T(4) (FT(4)), and TSH were measured in patients with massive metastases from papillary, follicular, or medullary thyroid carcinomas (31, 20, and seven patients, respectively). Patients without recurrence served as controls. Thyrotoxic patients were reexamined 1 wk after withdrawal of levothyroxine. Type 1 and type 2 iodothyronine deiodinase (D1 and D2) activities were measured in three tumor tissues from thyrotoxic patients.

MAIN OUTCOME

The serum FT(3) level and FT(3)/FT(4) ratio in the follicular carcinoma (FC) group were significantly higher than those in the papillary carcinoma group or patients without recurrence. Four patients (20%) in the FC group but none in the other groups demonstrated T(3) thyrotoxicosis or a FT(3)/FT(4) ratio greater than 3.5. One week after withdrawal of levothyroxine, both FT(3) and FT(4) levels decreased. Retrospective measurements of FT(3) in frozen stored sera demonstrated that FT(3) exceeded the upper normal limit when FT(4) began to decrease but remained within the normal range. Tumor tissues showed high D1 and D2 activities.

CONCLUSIONS

Twenty percent of patients with massive metastatic FC exhibited T(3) thyrotoxicosis, most likely due to increased conversion of T(4) to T(3) by tumor expressing high D1 and D2 activities. Occasional measurement of serum FT(3) in addition to FT(4) and TSH is recommended in patients with massive metastatic FC, especially when serum FT(4) decreases on fixed doses of levothyroxine.

Decrease of intrathyroidal CD161+Valpha24+Vbeta11+ NKT cells in Graves' disease

To clarify changes in the intrathyroidal natural killer T (NKT) cell subset, which prevents autoimmunity in patients with Graves' disease (GD), we examined intrathyroidal and peripheral lymphocytes in 11 patients with GD and peripheral lymphocytes in nine healthy volunteers using three-color flow cytometry. The proportion of CD161 (+) T cell receptor Valpha24 (+) Vbeta11 (+) cells, which represent the NKT cell subset, was lower in the thyroid of patients with GD than in the peripheral blood of the same patients and in the peripheral blood of healthy subjects. These results indicate that the proportion of intrathyroidal NKT cells is decreased in patients with GD and that this decrease may contribute to incomplete regulation of autoreactive T cells in GD.

Risk factors for recurrence to the lymph node in papillary thyroid carcinoma patients without preoperatively detectable lateral node metastasis: validity of prophylactic modified radical neck dissection

BACKGROUND

Although papillary carcinoma usually shows mild characteristics, it metastasizes and shows recurrence to the lymph node in high incidences. Of the two representative lymph node compartments to which papillary carcinoma metastasizes, the central compartment can be routinely dissected via the surgical incision made for thyroidectomy. However, the routine application of prophylactic lateral node dissection (modified radical neck dissection [MND]) remains controversial. In this study, we investigated risk factors for lymph node recurrence of papillary carcinoma to determine the appropriate application of prophylactic MND.

METHODS

We investigated risk factors for lymph node recurrence in 1,231 patients without preoperatively detectable lateral node metastasis who underwent thyroidectomy, central node dissection, and prophylactic MND for papillary carcinoma between 1987 and 1995.

RESULTS

The incidence of lateral node metastasis and the number of metastatic lateral nodes significantly increased with carcinoma size. The lymph node disease-free survival (LN-DFS) was also significantly worse in carcinoma with a maximal diameter greater than 3 cm. Massive extrathyroid extension, male gender, and age 55 years or older also reflected a poorer LN-DFS. The 10-year LN-DFS rates of patients with carcinoma having two and three or four of these features were low at 88.5% and 64.7%, respectively, although the rates of those with carcinoma having no or only one characteristic were better than 95%.

CONCLUSIONS

Prophylactic MND is recommended for cases of papillary carcinoma demonstrating two or more of the following four characteristics; male gender, age 55 years or older, maximal tumor diameter larger than 3 cm, and massive extrathyroid extension.

Risk factors contributing to a poor prognosis of papillary thyroid carcinoma: validity of UICC/AJCC TNM classification and stage grouping

BACKGROUND

In 2002, the UICC/AJCC TNM classification for papillary thyroid carcinoma was revised. In this study, we examined the validity of this classification system by investigating the predictors of disease-free survival (DFS) and cause-specific survival (CSS) in patients.

METHODS

We examined various clinicopathological features, including the component of the TNM classification, for 1,740 patients who underwent initial and curative surgery for papillary carcinoma between 1987 and 1995.

RESULTS

Clinical and pathological T4a, clinical N1b in the TNM classification, and patient age were recognized as independent predictors of not only DFS, but also CSS of patients. Tumor size, male gender, and central node metastasis independently affected DFS only. There were 1,005 pathological N1b patients, but pathological N1b did not independently affect either DFS or CSS. Regarding the stage grouping, clinical stage IVA including clinical N1b more clearly affected DFS and CSS than pathological stage IVA including pathological N1b.

CONCLUSION

Clinical stage grouping was more useful than pathological stage grouping for predicting the prognosis of papillary carcinoma patients possibly because pathological stage overestimates the biological characteristics of many pathological N1b tumors.

Lateral Mobilization of the Recurrent Laryngeal Nerve to Facilitate Tracheal Surgery in Patients with Thyroid Cancer Invading the Trachea Near Berry’s Ligament

BACKGROUND

Thyroid cancer often invades the trachea and the recurrent laryngeal nerve (RLN) at or near Berry's ligament, which fixes the thyroid gland to the trachea. In patients with thyroid cancer invading the trachea near the ligament, preservation of the RLN is very difficult. Regardless of whether the nerve is preserved or is resected and reconstructed, the presence of the nerve interferes with tracheal resection and repair. We proposed a new technique to solve this problem.

METHODS

Before tracheal surgery, the inferior pharyngeal constrictor muscle was divided along the lateral edge of the thyroid cartilage, and the RLN was mobilized and retracted laterally. We applied this technique in 11 patients with papillary thyroid carcinoma invading the trachea. Two patients demonstrated vocal cord paralysis preoperatively. The procedures used for tracheal surgery in this series were partial resection of the trachea with creation of a tracheocutaneostomy, that with direct suture, and shaving off the tumor in 7, 2, and 2 patients, respectively.

RESULTS

The RLN could be preserved and mobilized laterally in eight patients. While three patients demonstrated transient vocal cord paralysis, the remaining five had functioning cords postoperatively. In three patients the RLN was resected, and the remaining distal stump was mobilized and anastomosed with the ansa cervicalis. These patients recovered their voices and maximum phonation time increased to the normal level. The tracheocutaneous stoma was closed with local skin flap about four months later in all patients.

CONCLUSION

Lateral mobilization of the RLN facilitates the preservation of the nerve and the performance of tracheal surgery in patients with thyroid cancer invading the trachea at or near Berry's ligament.

Extranodal tumor extension to adjacent organs predicts a worse cause-specific survival in patients with papillary thyroid carcinoma

BACKGROUND

We previously reported that massive extrathyroid extension has an independent prognostic value in patients with thyroid papillary carcinoma. However, tumor extension to adjacent organs can be observed not only in primary tumor but also in metastatic nodes. In this study we investigated the clinical significance of extranodal tumor extension to adjacent organs (nodal ex) in papillary thyroid carcinoma.

METHODS

We classified all cases into three categories based on the degree of nodal ex: nodal ex0, no apparent extranodal tumor extension; nodal ex1, hard metastatic nodes with perinodal growth extending to adjacent organs, which require separation of the nodes from the organs; and nodal ex2, metastatic nodes with perinodal growth completely invading the adjacent organs and requiring excision of nodes together with these organs. We investigated the clinical significance of each grade in 1,692 patients who underwent initial surgery for papillary carcinoma between 1987 and 1995.

RESULTS

The presence of nodal ex was significantly linked to various clinicopathological features such as male gender, N1b, large number of metastatic nodes, pT4a, and distant metastasis. On univariate analysis, patients with either nodal ex1 or ex2 showed significantly worse disease-free and cause-specific survival rates, although these rates did not differ between patients with nodal ex1 and those with nodal ex2. Furthermore, multivariate analysis demonstrated that nodal ex independently predicts worse cause-specific survival of these patients.

CONCLUSIONS

Presence of nodal ex significantly reflects the biologically aggressive behaviors of papillary carcinoma and has a prognostic value, especially for cause-specific survival of patients.

Quantitative measurement of telomerase reverse transcriptase, thyroglobulin and thyroid transcription factor 1 mRNAs in anaplastic thyroid carcinoma tissues and cell lines

Anaplastic thyroid carcinomas (ATC) are undifferentiated tumors that show rapid progression and dissemination. The recent increase in knowledge about cancer stem cells has attracted marked interest in ATC, since these lesions are suggested to be closely related to thyroid stem cells (TSCs). Due to the rarity of ATCs, however, the gene expression patterns that characterize these lesions have not been fully clarified. Using real-time quantitative reverse transcription-polymerase chain reaction, we measured the mRNA expression levels of three representative genes, telomerase reverse transcriptase (hTERT), thyroglobulin and thyroid transcription factor 1 (TTF-1) in twelve frozen tissue samples of ATC and six cell lines derived from ATCs. All twelve ATC specimens and six ATC cell lines showed an increased expression of hTERT mRNA but the expression levels of hTERT mRNA did not show a clear difference between ATCs and other thyroid tumors. The mean expression level of thyroglobulin mRNA in the ATCs and ATC cell lines was <10(2) times higher than that in the differentiated thyroid carcinomas. All twelve ATCs showed a loss of TTF-1 mRNA expression, but two cell lines, TCO-1 and 8505C, expressed TTF-1 mRNA. In conclusion, ATC tissues and cell lines were characterized by the expression of hTERT and a loss of thyroglobulin expression, concordant with the general recognition. However, the loss of TTF-1 expression can not characterize ATC cells, as some ATC cell lines expressed TTF-1 mRNA abundantly. This information could contribute to clarifying the nature of ATCs and could be useful in detecting TSCs, which have not yet been identified.

Expression of oncofetal fibronectin mRNA in thyroid anaplastic carcinoma

BACKGROUND

Oncofetal fibronectin (onfFN) is a fetal protein, the expression of which is observed in papillary thyroid carcinomas but not in follicular tumors or in normal thyroid. Its expression in anaplastic thyroid carcinoma (ATC), however, has not been clarified, since only a few cases had been examined in previous studies.

METHODS

We examined the expression levels of onfFN mRNA in ATC tissues and cell lines derived from ATC by real-time quantitative reverse transcription-polymerase chain reaction (PCR) and in situ hybridization.

RESULTS

Increased expression of onfFN mRNA was observed in all cases of ATC regardless of the type of accompanying differentiated carcinoma and five of six ATC cell lines. Furthermore, expression of onfFN mRNA was observed in the majority of ATC cells in all six tissues examined by in situ hybridization.

CONCLUSION

These results confirm that expression of onfFN mRNA characterizes not only papillary thyroid carcinoma but also ATC. onfFN mRNA or protein may be a useful marker to identify anaplastic carcinoma cells and may be considered as an optimistic target in molecular-based therapy of ATC.

Prognosis of Patients with Benign Thyroid Diseases Accompanied by Incidental Papillary Carcinoma Undetectable on Preoperative Imaging Tests

BACKGROUND

Despite the recent wide availability of ultrasonography and fine-needle aspiration biopsy, endocrine surgeons often encounter incidental papillary carcinoma (IPC), that is a papillary carcinoma that had gone undetected by preoperative imaging studies but was identified by pathological examination of surgical specimens resected for benign thyroid diseases.

METHODS

The present study was developed to investigate the prognoses of 317 patients who underwent surgery for benign diseases involving IPC in comparison with the prognoses of 1,674 patients with clinically apparent papillary carcinoma detected preoperatively and diagnosed.

RESULTS

None of the patients underwent further surgery such as completion total thyroidectomy and node dissection immediately after the diagnosis of IPC. To date, 7 patients (2.2%) have had recurrences; 6 of those were locoregional recurrences and one was a bone metastasis. None of the patients have died of thyroid carcinoma. The disease-free survival of IPC patients was significantly better than that of clinically apparent papillary carcinoma patients and was similar to that of the subset of patients with papillary microcarcinoma without clinically apparent metastasis.

CONCLUSIONS

Because IPC is associated with good prognosis, further surgery, such as completion total thyroidectomy or lymph node dissection immediately after the diagnosis of IPC is not necessary.

Prognosis and Prognostic Factors of Follicular Carcinoma in Japan: Importance of Postoperative Pathological Examination

BACKGROUND

Follicular carcinoma is known to show a worse prognosis than papillary carcinoma because of distant metastasis in higher incidence. However, few studies have been published regarding the prognosis of follicular carcinoma patients in Japan, which prompted us to investigate this issue.

METHODS

We examined the prognosis and whether and how various clinicopathological features have affected disease-free survival (DFS) and cause-specific survival (CSS) of 334 patients who underwent initial surgery for follicular carcinoma.

RESULTS

In 18 patients (5.4%), curative surgery could not be achieved because of distant metastasis at surgery in 17 patients and local extension in 1 patient. For 316 patients who underwent curative surgery, 5-year and 10-year DFS rates were 88.4% and 75.3%, respectively. Poorly differentiated carcinoma and widely invasive carcinoma, together with some conventional prognostic factors, predicted poorer DFS of patients. On multivariate analysis, poorly differentiated carcinoma was an independent prognostic factor for DFS. The 5-year and 10-year CSS rates for these 334 patients were 96.4% and 90.4%, respectively. Curative surgery and poorly differentiated carcinoma were recognized as independent prognostic factors.

CONCLUSIONS

We can hypothesize that follicular carcinoma in Japan is generally a nonaggressive disease with a good prognosis. However, because poorly differentiated or widely invasive carcinomas showed a worse prognosis, postoperative pathological examination is important in predicting patient prognosis.

Aspiration biopsy-nucleic acid diagnosis of thyroid malignant lymphoma by vectorette PCR: experience of eight cases

The usefulness of a new method to detect B-cell monoclonality named VR, which is a combination of the digestion with restriction enzymes and vectorette PCR, in aspiration biopsy-nucleic acid diagnosis (ABND) of thyroid malignant lymphoma was investigated. ABND was performed in 12 patients in whom malignant lymphoma was suspected. Among the patients who underwent open surgery, monoclonality was detected in the aspirates in four (50%) of eight patients with malignant lymphoma, but was not detected in one patient with Hashimoto disease. ABND using VR is a useful adjunct of aspiration biopsy cytology in the diagnosis of thyroid malignant lymphoma.

Long-term follow-up for patients with papillary thyroid carcinoma treated as benign nodules

BACKGROUND

The recent prevalence of ultrasonography and fine-needle aspiration biopsy (FNAB) has facilitated the detection and diagnosis of papillary thyroid carcinoma. However, there are still cases that are preoperatively misdiagnosed and treated as benign nodules because ultrasonographic and FNAB findings do not provide sufficient evidence for a malignant diagnosis. In this study, we investigated the clinical outcomes of patients with papillary carcinoma that had not been recognized preoperatively.

PATIENTS AND METHODS

We investigated the prognoses of 56 patients with papillary carcinoma who underwent thyroidectomy without node dissection under a diagnosis of benign nodules.

RESULTS

None of the patients underwent further surgery such as completion total thyroidectomy and node dissection after the pathological diagnosis of papillary carcinoma was established. However, to date, only 3 patients (5.3%) showed recurrence 116, 133 and 148 months after the initial surgery, respectively. Two patients showed recurrence in the remnant thyroid and one showed recurrence in the bone. None of the patients have died of thyroid carcinoma.

CONCLUSION

Papillary carcinomas misdiagnosed as benign nodules on ultrasonography and FNAB are indolent and very slow-growing. Immediate further surgery is not needed for such cases, even if they were resected as benign nodules at the initial surgery.

Sustained fever resolved promptly after total thyroidectomy due to huge Hashimoto's fibrous thyroiditis

We encountered a 55-year-old female patient with Hashimoto's thyroiditis who showed persistent fever, and could not find any source of fever other than the large nontender goiter. Her fever continued with positive CRP for 6 months. Although we did not assume that the inflammation was related to Hashimoto's thyroiditis, total thyroidectomy was performed for cosmetic reasons; however, fever was resolved immediately after thyroidectomy. Pathological diagnosis was Hashimoto's chronic thyroiditis. Immunohistochemical staining showed that the follicular cells were positive for IL-1alpha, IL-1beta, and TNF-alpha. We believed that fever was induced by inflammatory cytokines produced in thyroid. The case indicated that Hashimoto's thyroiditis with nontender goiter could cause idiopathic fever.

Apoptosis-induced decrease of intrathyroidal CD4(+)CD25(+) regulatory T cells in autoimmune thyroid diseases

BACKGROUND

We previously showed that the proportion of CD4(+) T cells was lower and both the proportion and intensity of Fas expression on intrathyroidal CD4(+) T cells were higher in the thyroid than in the peripheral blood of patients with autoimmune thyroid disease (AITD).

OBJECTIVE

To clarify whether the intrathyroidal CD4(+)CD25(+) regulatory T (Treg) cells are decreased by Fas-mediated apoptosis in patients with AITD.

DESIGN

We examined intrathyroidal and peripheral lymphocytes in 20 patients with AITD (15 patients with Gravesâ disease and five patients with Hashimotoâs disease) and peripheral lymphocytes in 10 healthy volunteers by three-color flow cytometry.

MAIN OUTCOME

The proportion of CD4(+)CD25(+) cells was lower in the thyroid of patients with AITD than in the peripheral blood of the same patients or the peripheral blood of the healthy subjects. The proportions of CD4(+)CD25(+)CD69() cells and Forkhead box P3 (Foxp3)(+)CD4(+)CD25(+) cells, which constitute more specific Treg subsets than CD4(+)CD25(+) cells, were also lower in the thyroid than in the peripheral blood of patients with AITD. The proportion of apoptotic cells was higher among intrathyroidal CD4(+) cells than among peripheral CD4(+) cells and higher among intrathyroidal CD4(+)CD25(+) cells than among intrathyroidal CD4(+)CD25() cells.

CONCLUSION

These results indicate that intrathyroidal Treg cells are decreased in response to apoptosis in patients with AITD. This decrease in Treg cells may contribute to the incomplete regulation of autoreactive T cells in AITD.

Clinical significance of lymph node metastasis of thyroid papillary carcinoma located in one lobe

BACKGROUND

Previous studies have shown that lymph node metastasis can be of prognostic value. In this study, we investigated the clinical significance of node metastasis focusing on metastasis in the central compartment for patients with papillary carcinoma located in one lobe.

PATIENTS AND METHODS

We investigated the frequency of lymph node metastasis in 759 patients with papillary carcinoma to determine whether and how such metastasis affects disease-free survival (DFS).

RESULTS

Central node metastasis was observed in 63% of patients, and the frequency was increased in relation to tumor size. The frequency of lateral node metastasis was 62.0%, which was also directly related to tumor size. On multivariate analysis of cases showing tumor larger than 1 cm, central node metastasis was recognized as an independent prognostic factor of DFS. The frequency of metastasis to the paratracheal nodes contralateral to the tumor was drastically elevated for tumors larger than 1 cm, but metastasis to this region did not independently predict worse DFS.

CONCLUSION

Central node metastasis independently predicts a worse DFS for patients with papillary carcinoma larger than 1 cm.

Prognostic significance of extrathyroid extension of papillary thyroid carcinoma: massive but not minimal extension affects the relapse-free survival

OBJECTIVES

Extrathyroid extension has been recognized as a prognostic factor in papillary thyroid carcinoma. In the most recent version of the UICC TNM classification system, extrathyroid extension has been classified into two grades, minimal extension (extension to sternothyroid muscle or perithyroid soft tissues) and massive extension (extension to subcutaneous soft tissue, larynx, trachea, esophagus, or recurrent laryngeal nerve). In this study, we investigated the prognostic significance of each of the two types of extension.

PATIENTS AND METHODS

One thousand and sixty-seven patients with papillary thyroid carcinoma without distant metastasis at surgery, who underwent surgical treatment in Kuma hospital between 1990 and 1995 and had been followed postoperatively for 60 months or more, were enrolled in this study. The grading of extrathyroid extension was based on both pathological findings and intraoperative surgical findings.

RESULTS

In univariate analysis, although patients with massive extension showed a significantly worse relapse-free survival (RFS) rate than those with no or minimal extension (P < 0.0001), there was no difference in the RFS rate between patients with no extension and those with minimal extension. Among patients with massive extension, the RFS rate tended to be worse in those with posterior extension than in those with anterior extension (P = 0.0562). Furthermore, the RFS rate of patients with massive posterior extension only to the recurrent nerve demonstrated a better RFS rate than those with extension to other posterior organs (P = 0.0052). Multivariate analysis demonstrated that massive extrathyroid extension is recognized as an independent prognostic factor for RFS (P = 0.0003).

CONCLUSIONS

These findings suggest that (1) upgrading of T category for tumors with massive extension is appropriate, whereas that for tumors with only minimal extension is not, and (2) careful surgical treatment and postoperative follow-up are required for tumors with massive extension to posterior organs other than the recurrent laryngeal nerve.

Needle tract implantation of follicular neoplasm after fine-needle aspiration biopsy: report of a case

We herein report a 28-year-old woman with a follicular neoplasm showing subcutaneous needle tract implantation. One month after fine-needle aspiration biopsy (FNAB) for a tumor measuring 2.5 cm, the patient became aware of a subcutaneous nodule measuring about 1 cm at the needle insertion site. FNAB smear of this nodule showed poorly cohesive clusters of follicular cells with nuclear crowding, overlapping and resetting with some microfollicular architecture. Total thyroidectomy and resection of the subcutaneous nodule were performed. Although there was no capsular or vascular invasion of the nodule, the lesion was diagnosed as follicular carcinoma because of the subcutaneous seeding. Ki-67 labeling indices of the thyroid nodule and implanted tumor were higher than 5%. Furthermore, although galectin-3 was completely negative in the thyroid nodule, it was heterogeneously positive in the implanted tumor. It is therefore suggested that high cell proliferating activity as a characteristic of the original nodule and the subsequently obtained invasive characteristic of the implanted tumor contributed to this event. To date, there has not been any recurrence of the implanted lesion. Because implanted follicular carcinoma can be surgically removed, this complication should not impair the usefulness of FNAB.

Usefulness of ultrasonography for diagnosis of malignant lymphoma of the thyroid

BACKGROUND

Recent developments in ultrasonography (US) and the prevalence of ultrasound-guided fine needle aspiration biopsy (US-FNAB) has enabled physicians to detect and diagnosis thyroid diseases, including thyroid malignant lymphoma, much more easily.

METHODS

We describe our diagnostic strategy for malignant lymphoma on US screening. We screened possible malignant lymphoma patients by US characteristics such as enhanced posterior echoes.

RESULTS

Among 170 patients suspected of malignant lymphoma between 2000 and 2004, 74 (43.5%) were also diagnosed as having or suspected of lymphoma by US-FNAB. Five patients dropped out, and 67 of 69 patients who underwent surgical examination were pathologically diagnosed as having lymphoma. Finally, 79 (47.9%) of 165 US-suspected patients were confirmed as having lymphoma. Only 21.5% of lymphoma patients complained of rapidly growing goiter.

CONCLUSION

US screening for goiters contributes markedly to diagnosis of lymphoma at an early phase, facilitating early initiation of therapy.

Minimal extrathyroid extension does not affect the relapse-free survival of patients with papillary thyroid carcinoma measuring 4 cm or less over the age of 45 years

PURPOSE

In the most recent version of the UICC TNM classification system for thyroid carcinoma, tumors with minimal extrathyroid extension were classified as T3. In this study, we investigated whether this upgrading is appropriate for papillary thyroid carcinoma.

METHODS

We investigated the difference in the relapse-free survival (RFS) rate between patients with tumors having no, minimal, and massive extrathyroid extension in a series of 502 patients over the age of 45 years.

RESULTS

Patients with tumors showing massive extension showed a worse RFS rate except for those with tumors measuring 1 cm or less. However, there was no significant difference in RFS between tumors measuring 4 cm or less showing no or minimal extension. In an investigation of 409 patients without any clinically apparent node metastasis, the RFS of patients with tumors larger than 4 cm with massive extension was significantly worse than those with tumors measuring 4 cm or less, while the RFS of patients with tumors with either no or minimal extension did not depend on the tumor size.

CONCLUSIONS

These findings suggest that tumors with minimal extension should be classified to have the same T grade as those without such extension, and upstaging of such tumors is therefore not appropriate.

Delta Np73 expression in thyroid neoplasms originating from follicular cells

AIMS

p73, a homologue of p53, is known as a negative regulator of tumour progression. However, delta Np73, an isoform of p73 lacking the NH2-terminal transactivation domain plays an oncogenic role by interfering with the activity of p53 and TA (full-length transactivating isoforms) p73. In this study, we investigated the expression of delta Np73 in human thyroid neoplasms originating from follicular cells.

METHODS

We immunohistochemically investigated delta Np73 expression in 223 thyroid neoplasms. Delta Np73 expression level was evaluated as the sum of positivity score and intensity score.

RESULTS

Normal follicular cells did not express delta Np73, but 27.3% of follicular adenoma, 85.4% of follicular carcinoma, 99.2% of papillary carcinoma, and 95.7% of anaplastic carcinoma were positive for the transcript. Delta Np73 expression level did not differ between widely invasive and minimally invasive follicular carcinomas. In papillary carcinoma, the level was inversely linked to tumour size, extrathyroid extension, and clinically apparent metastasis. Furthermore, in anaplastic carcinoma, delta Np73 expression level was significantly lower than that in papillary carcinoma.

CONCLUSIONS

Our findings indicate that delta Np73 plays a role predominantly in the early phase of papillary carcinoma progression.

Sensitivity and Specificity of Intraoperative Recurrent Laryngeal Nerve Stimulation Test for Predicting Vocal Cord Palsy after Thyroid Surgery

INTRODUCTION

Recurrent laryngeal nerve (RLN) palsy after thyroidectomy, although infrequently encountered, can decrease quality of life. In addition to the hoarseness that occurs with unilateral RLN palsy, bilateral RLN palsy leads to dyspnea and often to life-threatening glottal obstruction. Therefore, intraoperative awareness of the nerve's status is of great importance. This study examined the sensitivity and specificity of a palpation technique to detect contraction of the posterior cricoarytenoid muscle (PCA) through the posterior hypopharyngeal wall while the RLN was being stimulated with a disposable nerve stimulator during thyroid surgery (the laryngeal palpation test) to predict postoperative RLN deficits.

METHODS

A total of 2197 RLNs in 1376 patients were identified to be at risk of injury during thyroidectomy performed between July 2003 and August 2004. Postoperative RLN integrity was assessed using direct laryngoscopy or laryngofiberoscopy to visualize vocal fold mobility.

RESULTS

Altogether, 76 RLNs failed to elicit a PCA contraction in response to nerve stimulation, and 80 cases of temporary vocal cord palsy and 21 cases of permanent vocal cord palsy were recognized on postoperative evaluation. For postoperative vocal cord palsy, the sensitivity and specificity of the laryngeal palpation test were 69.3% and 99.7%, respectively, with a positive predictive value of 92.1% and negative predictive value of 98.5%. For permanent vocal cord palsy, the sensitivity and specificity were 85.7% and 97.3%, respectively, with a positive predictive value of 23.7% and negative predictive value of 99.8%.

CONCLUSIONS

The laryngeal palpation test is not a particularly useful method for predicting the level of RLN function after thyroidectomy. All patients must be examined postoperatively by direct laryngoscopy or laryngofiberoscopy to check vocal cord mobility. Even if there is no contraction of the PCA and we detect vocal cord palsy immediately after surgery, vocal cord palsy often recovers within 1 year when visual preservation of RLN is successful.

Parapharyngeal metastasis from papillary thyroid carcinoma: a case diagnosed by thyroglobulin measurement in peroral fine-needle aspiration of a cystic metastatic lymph node

We report a case of a parapharyngeal cystic metastatic lymph node arising from papillary thyroid carcinoma (PTC). Parapharyngeal metastases arising from PTC are rare and correct diagnosis of the parapharyngeal mass before surgery is difficult. In this case, the diagnosis of a parapharyngeal mass was made pre-operatively by thyroglobulin measurement in peroral fine-needle aspiration with negative cytology.

Needle tract implantation of papillary thyroid carcinoma after fine-needle aspiration biopsy

Although fine-needle aspiration biopsy (FNAB) is a useful tool for diagnosing thyroid carcinoma, there are some risks of complications. In this study, we investigated tumor implantation by FNAB of papillary carcinoma. We compared the characteristics of the main tumors and implanted tumors of patients showing FNAB implantations. Between 1990 and 2002, 4912 patients underwent FNAB and were diagnosed as having papillary carcinoma. We encountered 7 cases of needle tract implantation, which account only for 0.14%. We reviewed these 7 cases as well as 3 other patients who underwent FNAB in other hospitals. The intervals between FNAB and detection of the implanted tumor ranged from 2 to 131 months. For these 10 patients, the main tumors in 6 were diagnosed as poorly differentiated carcinoma, and 7 showed extrathyroid extension. Five showed the development of implanted tumor after comparatively shorter intervals (2-68 months), and we classified these as the short interval group. The remaining 5 were classified as the long interval group, because tumor development occurred after 87-131 months. All 5 cases in the short interval group involved preoperatively detectable lymph node metastasis; those in the long interval group did not. The MIB-1 labeling index of the implanted tumor was high in 4 cases in the short interval group, but it was low in all cases in the long interval group. The implanted tumors could be surgically removed without recurrence at the focal sites. These findings indicate that, although high growth activity in the metastatic lesions may be a risk factor of FNAB, inducing the growth of implanted tumors along the needle tract within a short interval after the procedure, FNAB remains the most useful technique for diagnosing thyroid carcinoma. The incidence of implantation was low, and when it did occur, the tumors could be surgically removed without recurrence.

A Prophylactic Infusion of Calcium Solution Reduces the Risk of Symptomatic Hypocalcemia in Patients after Total Thyroidectomy

BACKGROUND

Several risk factors have been associated with post-operative transient hypocalcemia after thyroid surgery. However, there are no studies evaluating preventive measures to avoid symptomatic postoperative hypocalcemia. Although intravenous infusion of calcium improves hypocalcemic symptoms, it is unknown whether prophylactic infusion prevents symptoms of postoperative hypocalcemia.

PATIENTS AND METHODS

Five hundred and forty-seven patients underwent total thyroidectomy. Two groups were identified: group A (n = 243) received prophylactic intravenous drip infusion of 78-156 mg of calcium solution at 3-8 hours after operation, and group B (n = 304) received no prophylactic treatment. Prophylactic infusion was used only once if the patients did not have symptoms of hypocalcemia. Serum calcium (Ca) levels, intact parathyroid hormone (i-PTH) levels on the first postoperative day (1st POD), and the prevalence of symptoms of hypocalcemia were prospectively analyzed.

RESULTS

The serum Ca levels at the 1st POD in group A patients (7.91 +/- 0.49 mg/dl, mean +/- SD) was significantly higher than group B patients (7.65 +/- 0.54, P < 0.0001), while the serum i-PTH levels were not significantly different between the two groups. The prevalence of numbness and/or tetany before noon on the 1st POD was significantly lower in group A patients. Prophylactic infusion of calcium solution reduced the prevalence of tetany from 8.6% to 2.1%.

CONCLUSION

A prophylactic infusion of calcium solution after total thyroidectomy may be useful in reducing the development of symptomatic hypocalcemia and reduces the patients' risk of having discomfort and anxiety due to hypocalcemia.

Tensin3 is a novel thyroid-specific gene

Thyroid-specific genes, such as thyroid peroxidase, thyroglobulin, Na+/I- symporter and thyroid-stimulating hormone receptor, play fundamental roles in thyroid function and relate to many pathological conditions. Using sequence specific-differential display, we detected three genes that showed higher expression levels in normal thyroid tissues than in thyroid tumor tissues. After subcloning and sequencing analysis, one of the genes was revealed to be tensin3. The expression level of tensin3 was examined with real-time quantitative PCR analysis. Its expression levels were more depressed in thyroid tumor tissues than in normal thyroid tissues. The decrease was even more evident in two anaplastic carcinomas. High and moderate levels of tensin3 mRNA expression were observed in the thyroid and placenta respectively. Tensin3 mRNA was expressed only in low levels in other tissues, such as the brain, heart, lung, liver, pancreas, kidney, skeletal muscle, white blood cells and prostate. These results show that tensin3 is a novel thyroid-specific gene and further investigations may reveal its relation to thyroid function or thyroid disease.

Favorable surgical results in 433 elderly patients with papillary thyroid cancer

Papillary thyroid cancer (PTC) has a good prognosis among patients younger than 45 years old, but the prognosis in elder is worse and treatment strategy is not well established. We retrospectively analyzed the clinical features and outcomes of 433 patients with PTC aged 70 years or older. The patients consisted of three groups: group A (n = 327); patients receiving surgical treatment, group B (n = 51); patients with microcancer (maximal diameter, < or = 1.0 cm) who did not undergo surgical treatment, group C (n = 55); patients in whom surgery was contraindicated due to age, high surgical risk or complication by other illnesses. In group A, the mean tumor size was 2.6 +/- 1.5 cm, and 218 patients (66.7%) had pathologically confirmed lymph node metastasis; 110 patients (33.6%) had extrathyroidal invasion. The 5- and 10-year overall survival rates (OSR) in group A were 97.2% and 85%, respectively, which was significantly higher than the 5-year OSR in group C (62.6%). The 5- and 10-year disease-specific survival rates (DSSR) in group A were 98.5% and 91.3%, respectively, which was also significantly higher than the 5-year DSSR in group C (81.8%). Although the patients in group B did not receive any treatment, none of them demonstrated cause-specific death or progression of disease. Papillary thyroid cancer in elderly patients, except for microcancers, may be biologically aggressive. Thus surgery is recommended for these patients, if their general status is judged able to tolerate the stress of anesthesia and surgery.

Clinical Significance of Metastasis to the Central Compartment from Papillary Microcarcinoma of the Thyroid

We previously demonstrated that for papillary microcarcinoma (PMC), (1) patients with lateral lymph node metastasis detected on preoperative ultrasonography (US) are more likely to develop recurrence, and (2) dissection of the lateral compartment does not improve the prognosis of patients without US-detectable lateral metastasis. In this study, we focused on metastasis from PMC to the central compartment. We investigated the clinical significance of lymph nodes in the central compartment using the same series of 600 patients as used in the previous study. Ultrasound-diagnosed central node metastasis could be found in 30 patients (20.0%). Although the specificity of US for detecting central node metastasis was 99.1%, sensitivity was only 10.9%. Neither US-diagnosed nor pathologically confirmed central node metastasis affected the disease-free survival (DFS) rate of PMC patients. Furthermore, in cases where PMC was located only in one lobe, central node dissection in the contralateral lobe did not improve the DFS rate. These findings suggest that, for PMC, (1) US is an insensitive technique for detecting the central node metastasis, (2) the presence of central node metastasis is unrelated to DFS of patients, and (3) when performing lobectomy for PMC involving only one lobe, dissection of the central compartment in the contralateral lobe is optional.

Stretching exercises to reduce symptoms of postoperative neck discomfort after thyroid surgery: prospective randomized study

Patients who undergo thyroid surgery frequently suffer from unpleasant symptoms such as a stretching, choking, or pressing feeling or discomfort in the neck for a long time. The usefulness of rehabilitation (i.e., a stretching exercise) for reducing these symptoms after surgery has never been studied. In the present study, attempts were made to evaluate the usefulness of the stretching exercise in reducing disagreeable postoperative symptoms in the patients who had undergone thyroid surgery. A total of 409 patients, including 234 thyroid cancer patients, were randomly divided into a stretching group (n = 204) and a control group (n = 205). Patients in the stretching group were instructed that the stretching exercise was to be performed three times a day beginning the morning following surgery. A questionnaire survey was performed before surgery and then 1 week, 1 month, 6 months, and 1 year after surgery. Total symptom scores obtained from the questionnaire survey from the control group and the stretching group were compared. The use of analgesics was also investigated. Postoperative neck symptoms declined gradually over the course of a year, and the total symptom scores were significantly (p < 0.001) lower in the stretching group than in the control group at all points throughout the year (1 week, 1 month, 6 months, and 1 year). The mean requirement for the use of analgesics during hospitalization was significantly (p < 0.0001) less in the stretching group (1.6 +/- 2.3 tablets, mean +/- SD) than in the control group (3.1 +/- 3.8 tablets). The stretching exercise had effectively reduced postoperative neck symptoms and also reduced the use of analgesics after thyroid surgery.