Takashi Mimura

Lymph node metastasis from 259 papillary thyroid microcarcinomas: frequency, pattern of occurrence and recurrence, and optimal strategy for neck dissection.

ObjectiveTo determine the frequency and pattern of lymph node metastasis (LNM) from papillary thyroid microcarcinoma (PTMC) and the results of node dissection, and to establish the optimal strategy for neck dissection in these patients. Summary Background DataMost PTMCs carry a favorable prognosis, but a few present with palpable lymphadenopathy. Patients with LNM are at risk for nodal recurrence, although they do not have higher mortality. The frequency and pattern of LNM from PTMC and the results of node dissection are not well established. MethodsThe frequency and pattern of LNM from 259 PTMCs were analyzed according to the size and location of the primary tumor. Of the 259, 24 with palpable nodes underwent therapeutic node dissection and the other 235 patients without palpable nodes underwent prophylactic node dissection. The authors compared the results of node dissection between the therapeutic group and the prophylactic group, and between PTMCs 5 mm or smaller and PTMCs larger than 5 mm. The authors also compared nodal recurrence between the prophylactic group and a no-lymph-node-dissection group (155 PTMCs). ResultsOverall, 64.1% (166/259) and 44.5% (93/209) had node involvement of the central and ipsilateral lateral compartment, respectively. Pretracheal (43.2%), ipsilateral central (36.3%), and ipsilateral mid-lower (37.8%) jugular were more commonly involved. LNM was more frequent in the therapeutic group than in the prophylactic group (95.8% vs. 60.9% for central compartment, 83.3% vs. 39.5% for ipsilateral lateral compartment). Nodal recurrence was more common in the therapeutic group than in the prophylactic group (16.7% vs. 0.43%), but did not differ between the prophylactic group and the no-dissection group (0.43% vs. 0.65%). The tumor size did not influence nodal recurrence. Nodal recurrence preferentially occurred in ipsilateral mid-lower jugular nodes. ConclusionsPatients who have PTMC presenting with palpable lymphadenopathy should have therapeutic node dissection. Prophylactic node dissection is not beneficial in those without palpable lymphadenopathy.

Papillary microcarcinoma of the thyroid

Papillary microcarcinoma of the thyroid has been often detected by aspiration biopsy cytology performed with ultrasonographic guidance. Autopsy studies also have often revealed small thyroid carcinomas, and it was concluded that most small thyroid carcinomas should not be regarded as a clinical matter. In this study, 112 patients with papillary microcarcinoma 10 mm or less in size treated between 1992 and 1995 were analyzed. There were 104 females and 8 males, with a mean age of 46.0 years. Diagnosis of papillary carcinoma was made preoperatively in 100 of these patients (89.3%), and 77 patients underwent aspiration biopsy cytology under ultrasound guidance. Seventy of these patients underwent modified neck dissection, and 63.8% of these patients had lymph node metastases. The number of lymph node metastasis increased as primary tumor size increased. There was no clear border or clinical differences between primary tumors 10 mm or less and tumors more than 10 mm. One patient had lymph node recurrence after surgery and another patient had recurrent nerve palsy at the first visit. Based on these findings, papillary microcarcinoma should be treated surgically.Papillary microcarcinoma of the thyroid has been often detected by aspiration biopsy cytology performed with ultrasonographic guidance. Autopsy studies also have often revealed small thyroid carcinomas, and it was concluded that most small thyroid carcinomas should not be regarded as a clinical matter. In this study, 112 patients with papillary microcarcinoma 10 mm or less in size treated between 1992 and 1995 were analyzed. There were 104 females and 8 males, with a mean age of 46.0 years. Diagnosis of papillary carcinoma was made preoperatively in 100 of these patients (89.3%), and 77 patients underwent aspiration biopsy cytology under ultrasound guidance. Seventy of these patients underwent modified neck dissection, and 63.8% of these patients had lymph node metastases. The number of lymph node metastasis increased as primary tumor size increased. There was no clear border or clinical differences between primary tumors 10 mm or less and tumors more than 10 mm. One patient had lymph node recurrence after surgery and another patient had recurrent nerve palsy at the first visit. Based on these findings, papillary microcarcinoma should be treated surgically.

Clinical evaluation of color Doppler imaging for the differential diagnosis of thyroid follicular lesions

Ultrasonography (US) of the thyroid gland has recently proved to be a useful clinical diagnostic method, and the newly developed high-resolution US with a color Doppler flow mapping function can reveal fine details of the thyroid gland and the hemodynamic features of a thyroid neoplasm. US can yield a diagnostic accuracy of more than 90% for thyroid carcinoma, especially papillary carcinoma. However, neither conventional B-mode US imaging nor aspiration biopsy cytology has delivered satisfactory results for follicular carcinoma. The aim of this study was to evaluate the clinical usefulness of color Doppler imaging for the differential diagnosis of thyroid follicular lesions. A color Doppler scan was performed in 310 patients with a solitary cold nodule, and a combination of B-mode US and color Doppler findings, including tumor vascularity and results of a fast Fourier transform (FFT) analysis were used to create the following diagnostic grading system for differential diagnosis of follicular lesions: grade 1, benign follicular lesion [no color flow mapping (CFM) inside the nodule]; grade 2, benign peripheral type [CFM only in peripheral area, pulsatility index (PI) < 1.0]; grade 3, suspected follicular carcinoma (penetrating CFM, vascularity moderate); grade 4, follicular carcinoma (high-velocity penetrating CFM, PI = 1.0). All patients were subjected to surgical resection, and histologic examination was used to confirm the diagnosis. The grades of the177 adenomatous nodules were as follows: grade 1, 46.9%; grade 2, 48.0%; grade 3, 5.1%; grade 4, 0%. The corresponding percentages for the 89 follicular adenomas were 16.9%, 49.4%, 30.3%, and 3.4%; and for the 44 follicular carcinomas they were 0%, 13.6%, 45.5%, and 40.9%. On the assumption that grade 1 and 2 lesions are benign and grade 3 and 4 lesions are malignant, 38 of the 44 follicular carcinomas and 227 of the 266 benign tumors had been accurately diagnosed, yielding a sensitivity of 88.9%, a specificity of 74.2%, and an accuracy of 81.0% for the grading system. Color Doppler imaging of 310 follicular tumors has revealed that high-velocity pulsatile blood flow penetrating the tumor is a characteristic finding of follicular carcinoma and is a new diagnostic criterion for performing color Doppler imaging. The differential diagnostic grading scores for color Doppler examinations and the results of FFT analysis demonstrate that US with the color Doppler function can play an important role in the differential diagnosis of thyroid tumors.

Surgery for patients with thyroid carcinoma invading the trachea: Circumferential sleeve resection followed by end-to-end anastomosis

BACKGROUND Curative surgery can be accomplished by tracheal resection in patients with thyroid carcinoma invading the trachea; however, there is controversy regarding the extent of the tracheal resection. In this study we investigated by means of histologic examination the mode of tracheal invasion by thyroid carcinoma. METHODS Twenty-one patients with thyroid carcinoma invading the trachea underwent circumferential sleeve resection of the involved trachea. The extent of invasion of the tracheal wall on the adventitial and mucosal sides was compared on histologic examination. RESULTS Three to nine tracheal rings were resected. Assessment of longitudinal spread showed that one to six rings (mean; 3.1 rings) were invaded on the adventitial side but only zero to four rings (mean; 1.9 rings) on the mucosal side, with invasion on the mucosal side never exceeding invasion on the adventitial side. In contrast, examination of circumferential spread showed invasion on the mucosal side exceeding invasion on the adventitial side in five cases. CONCLUSIONS Our results suggest that when the extent of invasion of the adventitia is considered, carcinoma tissue may be left behind on the mucosal side of the trachea when partial wedge resection is performed and that, whenever feasible, circumferential sleeve resection should be performed in patients with thyroid carcinoma invading the trachea.

Resection of the trachea infiltrated by thyroid carcinoma.

Twenty-four thyroid carcinoma patients with infiltration of the trachea were treated surgically. The histological diagnosis in these cases included papillary adenocarcinoma in 22 different patients, medullary carcinoma in one patient, and undifferentiated carcinoma in one patient. In 19 of the patients hemoptysis was noted, and dyspnea was present in ten patients. In 14 of the 24 patients the carcinoma was diagnosed by radiographs of the neck, while in seven patients it was demonstrated bronchoscopically. In three patients tracheal infiltration by thyroid carcinoma was diagnosed by biopsy of the tracheal wall at operation. When the tracheal wall was infiltrated by thyroid carcinoma, treatment consisted of circumferential resection of the involved segment of the trachea followed by an end-to-end anastomosis. Of the 24 patients, 17 survived and six died. In the 17 patients who survived, 13 were disease free. Of this number, six survived more than five years after the initial tracheal resection.

Papillary carcinoma of the thyroid. Tall cell variant with extensive lymphocyte infiltration.

Thirteen cases of tall-cell variant of papillary thyroid carcinoma (PTC) showing extensive lymphocyte and plasma cell infiltration within the fibrous stalks of the papillary architecture were compared with age-, sex-, and tumor size-matched cases of ordinary tall-cell variant without extensive lymphocyte infiltration and also with cases of PTC of the conventional type. All cases of the tall-cell variant of PTC with extensive lymphocyte infiltration exhibited the histologic features of chronic thyroiditis. Dissemination of tumor cells with the thyroid was significantly less frequent than in control cases, but there was no difference between the incidences of lymph node metastasis. Immunohistochemically, the lymphocytes infiltrating the carcinoma focus were mainly CD20+, CD45+, and CD45RO+ cells, that is, basically the same as those found in foci of chronic thyroiditis. No tumor recurrence was observed during the mean follow-up period of 3 years 8 months. The results of this study suggest that the tall-cell variant of PTC with extensive lymphocyte infiltration has less aggressive characteristics and a more favorable prognosis.

Hürthle cell tumor of the thyroid : Analysis of 188 cases

We reviewed 188 cases of Hürthle cell tumor of the thyroid (HCT) between 1982 and 1996. There were 160 women and 28 men with a mean age of 51.8 years. Thirty-one of the patients had cancer, and the others had adenoma. Age, size of the primary tumor, and preoperative thyroglobulin level were not significantly different in the cancer and adenoma patients. The gender ratio, however, was significantly different (p<0.05). Recurrent HCT was observed in three patients with adenoma. Two patients had subcutaneous recurrence (suspected implantation), and the other patient had recurrence in the residual thyroid gland. All patients with recurrence of adenoma underwent partial lobectomy at the initial operation. Three cancer patients had recurrent disease. Locoregional recurrence was observed in one patient and distant metastases in two patients (lung in one, lung and bone in one). One of the patients with distant metastasis died from the disease, and the other is alive with the disease. Tumor implantation was observed in patients with adenoma, so intraoperative handling of the tumor requires care. It also means that this tumor, even though benign, is aggressive in terms of proliferative activity. All patients with Hürthle cell tumor should be treated by total lobectomy at least. The outcome of the cancer patients was not as poor as in previous reports.RésuméOn a revu les dossiers de 108 cas de tumeur de cellules de Hürthle de la thyroïde (HCT) observées entre 1982 et 1996. II y avait 160 femmes et 28 hommes avec un âge moyen de 51.8 ans. Trente et un patients avaient un cancer alors que les autres avaient un adénome. L’âge, la taille de la tumeur primitive et le taux de thyroglobuline préopératoire ne différaient pas de facon significative entre les patients ayant un cancer ou un adénome. Le sexe ratio, cependant, différait de façon significative (p<0.05). On a observé une récidive de tumeur de cellules de Hürthle chez trois patients ayant un adénome. Deux patients avaient une récidive sous-cutanée, probablement par implantation, alors que le troisième avait une récidive au niveau du moignon thyroïdien. Tous les patients ayant une récidive d’adénome ont eu une lobectomie partielle au moment de l’intervention initiale. Trois patients ont eu une récidive. On a observé une récidive locorégionale chez un patient et des métastasesà distance chez deux patients (poumon n=1, os, n=1). Un seul ayant des métastasesà distance est décédé. L’implantation tumorale a été observée chez les patients ayant un adénome et ainsi, la manipulation de la tumeur en peropératoire semble être un facteur important. II va de soi, également, que la tumeur, même si elle est bénigne, est agressive en termes d’activité proliférative. Tous les patients ayant une HCT doivent être traités, au moins, par lobectomie totale. L’évolution des patients ayant un cancer n’était pas aussi péjorative que rapporté antérieurement.ResumenSe revisan entre 1982 y 1996, 188 casos de tumores de tiroides con células de Hürthle (HCT). 160 eran mujeres y 28 hombres con edad media de 51.8 anõs. Se registraron 31 casos de cánceres, siendo los restantes adenomas. La edad, el tamanõ del tumor primario y los niveles preoperatorios de tiroglobulina no mostraron diferencias significativas entre los cánceres y los adenomas. Sin embargo, la incidencia por lo que al sexo se refiere fue muy significativa (p<0.05). Recidiva del HCT se constató en 3 pacientes con adenomas. Dos presentaron recidivas subcutáneas (sospechosas de implantación celular) y otro enfermo desarrolló la recidiva en tejido glandular residual del tiroides. En todos los pacientes con recidiva adenomatosa se habia efectuado, como operación inicial, una lobectomia. Tres enfermos con cáncer recidivaron; recidiva loco-regional se observó en uno y metástasis a distancia en dos (una pulmonar y otra ósea); uno de los pacientes con metástasis a distancia falleció; el otro vive con su enfermedad. Implantación tumoral se constató en pacientes con adenoma por lo que la manipulación intraoperatoria de estos tumores requiere sumo cuidado. Este hecho demuestra que los HCT aunque sean benignos son agresivos por lo que a su actividad proliferativa se refiere. En todos los pacientes con HCT debe realizarse al menos una lobectomia total. Los resultados en pacientes con cáncer no fueron tan malos como los referatados en trabajos previos.

Anaplastic transformation of papillary thyroid carcinoma in recurrent disease in regional lymph nodes: A histologic and immunohistochemical study

Although the prognosis of papillary thyroid carcinoma is favorable in most cases, recurrent disease in the regional lymph nodes is not uncommon, and some patients die of recurrent disease that ultimately becomes unresectable. We studied the proliferative activity of cancer cells in recurrent foci in lymph nodes to see whether repeated recurrences might result in anaplastic transformation of papillary thyroid carcinoma.

Metastases to the regional lymph nodes, lymph node recurrence, and distant metastases in nonadvanced papillary thyroid carcinoma

To investigate the biological characteristics of papillary thyroid carcinoma from the perspectives of lymph node metastasis, lymph node recurrence, and distant metastasis, 746 patients with nonadvanced papillary thyroid carcinoma were retrospectively studied. There were 76 men and 670 women with a mean age of 42.7 years. The rate of lymph node metastasis was significantly higher in young patients (aged less than 30 years). Lymph node recurrence was observed in 80 patients and distant metastasis in 13, being seen with significant frequency in the young and elderly (aged over 50 years) patients and in the men. The frequency of distant metastasis was significantly greater in the elderly patients and in those with lymph node recurrence. These findings indicate that the role of regional lymph nodes and the clinical meaning of lymph node recurrence differ between young and elderly patients.

PCNA and Ki-67 as Prognostic Markers in Human Parathyroid Carcinomas

Background: It is widely accepted that histological diagnosis of parathyroid tumors is established with great difficulty. Carcinomas cannot be reliably separated from adenomas by histology alone. In this study, immunohistochemical staining for proliferating cell nuclear antigen (PCNA) and Ki-67 was determined in 10 cases of parathyroid carcinomas, labeling indices (LIs) were calculated, and the results were correlated with the clinical outcomes.Methods: Ten cases of formalin-fixed, paraffin-embedded tissue with surgically resected parathyroid carcinoma were used. Immunohistochemical staining for PCNA and Ki-67 was performed and the LIs were calculated. We also examined whether LI could become a useful marker for parathyroid carcinomas.Results: Although nine patients with minimally invasive growth without recurrence of the tumor showed a low LI for both markers, one patient with a widely invasive neoplasm, and who died, had a high LI.Conclusions: These results suggested that the LI of PCNA and Ki-67, in addition to the histological appearance, may be markers of the biological behavior of parathyroid carcinomas. However, this study was on a small scale, so it may be valuable to repeat these studies in a larger group of patients with better defined histological criteria.