Thyroid carcinoma: current controversies

Usefulness of electrosurgical techniques in thyroid gland surgery

Wide propagation of new generation of electrosurgical devices such as bipolar vessel sealing systems (eg. Thermostapler® by EMED) enabled seamless closing of blood vessels with a diameter up to 7 mm while maintaining the necessary safety margin, as well as reducing the duration of the operation. We decided to verify these reports in our material. AIM OF THE STUDY was comparison of thyroid surgery performed with the electrocautery tool - Thermostapler ® by EMED with surgery using classic hemostasis technique to evaluate the operative time and complications in the form of bleeding, recurrent laryngeal nerve paralysis, symptoms of hypoparathyroidism, and wound infection.

MATERIAL AND METHODS

We retrospectively analyzed 256 patients operated in the Department of General and Proctological Surgery Solec Hospital in Warsaw due to inert thyroid goitre. All patients underwent total thyroidectomy. Patients were divided into two groups. The first group consisted of 126 patients operated in 2000, using classic techniques of hemostasis. While the second group consisted of 130 patients operated in 2007-2008 with Thermostapler®. We compared duration of surgery and the incidence of postoperative complications.

RESULTS

The operative time was significantly shorter (average 18 minutes) in the second group of patients. We also recorded a statistically significant decrease in the incidence of complications in the group operated with Thermostapler.

CONCLUSIONS

Use of bipolar vessel sealing system in a decisive manner shortens the duration of operation. Use of bipolar vessel sealing system also enables a radical reduction in the incidence of complications rate such as bleeding, recurrent laryngeal nerve paralysis, symptoms of hypoparathyroidism, and wound infection. In the future, similar studies should be performed to assess the real costs resulting from the use Thermostapler®.

Meta-analysis of thyroidectomy with ultrasonic dissector versus conventional clamp and tie

Background

We conducted a systematic review to evaluate the role of Ultrasonic dissector (UAS) versus conventional clamp and tie in thyroidectomy.

Materials and methods

We searched for all published RCT in into electronic databases. To be included in the analysis, the studies had to compare thyroidectomy with UAS versus conventional vessel ligation and tight (conventional technique = CT). The following outcomes were used to compare the total thyroidectomy group with UAS versus CT group: operative duration, operative blood loss, overall drainage volume during the first 24 hours, transiet laryngeal nerve palsy, permanent laryngeal nerve palsy, transiet hypocalcaemia and permanent hypocalcaemia.

Results

There are currently 7 RCT on this issue to compare thyroidectomy with UAS versus CT. From the analysis of these studies it was possible to confront 608 cases: 303 undergoing to thyroidectomy with UAS versus 305 that were treated with CT. Actually, it was shown a relevant advantage of cost-effectiveness in patients treated with UAS; there is a statistically significant reduction of the operative duration (weighted mean difference [WMD], -18.74 minutes; 95% confidence interval [CI], (-26.97 to -10.52 minutes) (P = 0.00001), intraoperative blood loss (WMD, -60.10 mL; 95% CI, -117.04 to 3.16 mL) (P = 0.04) and overall drainage volume (WMD, -35.30 mL; 95% CI, -49.24 to 21.36 mL) (P = 0.00001) in the patients underwent thyroidectomy with UAS. Although the analysis showed that the patients who were treated with USA presented more favourable results in incidence of post-operative complications (transient laryngeal nerve palsy: P = 0.11; permanent laryngeal nerve palsy: not estimable; transient hypocalcaemia: P = 0.24; permanent hypocalcaemia: P = 0.45), these data didn't present statistical relevance.

Conclusion

This meta-analysis shown a relevant advantage only in terms of cost-effectiveness in patients treated with UAS; it is subsequent to statistically significant reduction of operation duration, intraoperative blood loss and of overall drainage volume during the first 24 hours. Although the analysis showed that the patients who were treated with UAS presented more favourable results in incidence of post-operative complications (transiet laryngeal nerve palsy; transiet hypocalcaemia and permanent hypocalcaemia), these data didn't present statistical relevance.

Follicular thyroid carcinoma invades venous rather than lymphatic vessels

Follicular thyroid carcinoma (FTC) tends to metastasize to remote organs rather than local lymph nodes. Separation of FTC from follicular thyroid adenoma (FTA) relies on detection of vascular and/or capsular invasion. We investigated which vascular markers, CD31, CD34 and D2-40 (lymphatic vessel marker), can best evaluate vascular invasion and why FTC tends to metastasize via blood stream to remote organs. Thirty two FTCs and 34 FTAs were retrieved for evaluation. The average age of patients with FTA was 8 years younger than FTC (p = 0.02). The female to male ratio for follicular neoplasm was 25:8. The average size of FTC was larger than FTA (p = 0.003). Fourteen of 32 (44%) FTCs showed venous invasion and none showed lymphatic invasion, with positive CD31 and CD34 staining and negative D2-40 staining of the involved vessels. The average number of involved vessels was 0.88 ± 1.29 with a range from 0 to 5, and the average diameter of involved vessels was 0.068 ± 0.027 mm. None of the 34 FTAs showed vascular invasion. CD31 staining demonstrated more specific staining of vascular endothelial cells than CD34, with less background staining. We recommended using CD31 rather than CD34 and/or D2-40 in confirming/excluding vascular invasion in difficult cases. All identified FTCs with vascular invasions showed involvement of venous channels, rather than lymphatic spaces, suggesting that FTCs prefer to metastasize via veins to distant organs, instead of lymphatic vessels to local lymph nodes, which correlates with previous clinical observations.

[Early diagnosis, therapy, follow-up and survival in patients with thyroid malignancies]

The Aim of the paper was to give a review of an early diagnosis, therapy, follow-up and survival rate of patients with thyroid malignancy (TM). The paper presented the algorithm of early diagnosis: clinical, scintigraphic and ultrasonographic examination together with fine needle biopsy, cytologic analysis of the smear and biopsy ex tempore of the clear and suspected thyroid node to malignancy. Therapy of all TM forms was mainly surgical: postsurgical treatment was dependent on the type of malignancy: radioiodine 131-I, radiologic treatment, chemotherapy and radioimmunotherapy, (the latest one being in the phase of a clinical research). Follow-up was in accordance with the protocol and it was necessary because it contributes to the survival rate. In the presentation of survival rate for differentiated and medullar carcinomas we gave our results and literature data, while for the other malignancies only data from literature were presented.

CONCLUSION

Only an early diagnosis of the nodular goiter together with an up-to-date treatment can cure TM patients in a high percentage and prevent development of a terminal stage of the disease which is extremely severe in all forms of this malignancy.

[Follicular carcinoma of the thyroid gland]

Follicular thyroid cancer is the second most common thyroid malignancy. This tumor has a predisposition for hematogenous dissemination an extra thyroid spread. Accurate cytological diagnosis of follicular thyroid cancer is not possible and this fact highlights the necessity for surgical treatment of any suspicious thyroid nodule. Aggressiveness of this tumor is greater than in the case of papillary thyroid cancer and it is the reason for radical surgical treatment of follicular thyroid cancer. Total thyroidectomy facilitates later adjuvant therapy with thyroid hormones and radioiodine. This procedure improves the outcome and the risk of relapse. Results of our study clearly demonstrate that diagnosis of follicular thyroid cancer in us is established in the early phase of the disease (78.57%), but the significant number of the patients (21.43%) is still in the advanced phase of the disease.

Distribution of lymph node micrometastasis in pN0 well-differentiated thyroid carcinoma

BACKGROUND

The role of lymph node dissection in the treatment of differentiated thyroid carcinoma remains controversial, and the benefit of therapy is debatable. This study was designed to identify the precise localization of lymph node micrometastases (LNMM) and map their cervical involvement in relation with the tumor location within the thyroid gland.

METHODS

A total of 2551 cervical lymph nodes were obtained from 80 patients with well-differentiated thyroid cancer. They were diagnosed as clear lymph nodes by hematoxylin and eosin stain and then examined immunohistochemically with cytokeratins (AE1/AE3) for evidence of micrometastases.

RESULTS

Forty-two patients out of 80 (53%) had LNMM. Forty-eight patients (60%) had the tumor confined to only one third of 1 of the 2 lobes of the thyroid gland or isthmus. The frequencies and locations of LNMM in patients were 50% (3/6) in the deep upper cervical nodes, with tumors localized in the upper third; 31% (5/16) in the paraglandular nodes, with tumors affecting the middle third; 63% (12/19) in the paratracheal nodes, with tumors affecting the lower third of the thyroid lobe; and 71% (5/7) in the pretracheal nodes in the isthmus-located tumor. All the LNMM occurred on the ipsilateral side of the tumor.

CONCLUSIONS

When thyroid carcinoma is located in the upper third of the thyroid lobe, the LNMM are found in the direction of upward lymphatic flow. When the tumor is located in the lower third or isthmus, LNMM are directed downward. In addition, early thyroid carcinoma micrometastases do not cross the midline but remain on the ipsilateral side of the tumor.

Well-differentiated thyroid carcinoma

PURPOSE

This study presents our experience with 728 patients treated in our department for well-differentiated thyroid carcinoma between 1954-1994.

MATERIALS AND METHODS

The retrospective evaluation of the prognostic implications of the clinical and pathological findings was performed. Age, sex, histological variants, tumor size, and locoregional and distant spread were evaluated as risk factors in relation to the prognosis.

RESULTS

During follow-up, which ranged from 1 to 31 years, 125 locoregional and/or distant metastases developed (17.2% of the patients), 87 of which occurred in the first 10 years after initial therapy. Thirty-two patients with papillary cancer and 20 with follicular cancer died of causes related to malignancy of the thyroid.

CONCLUSION

The experience gained in our department has led us to adopt an aggressive approach in the treatment of patients with well-differentiated carcinoma of the thyroid gland.

Parathyroid autotransplantation during thyroidectomy. Results of long-term follow-up

SUMMARY BACKGROUND DATA

Permanent hypoparathyroidism is a recognized complication of thyroidectomy. Operative strategies to prevent this complication include preservation of parathyroid glands in situ and autotransplantation of parathyroid glands resected or devascularized during thyroidectomy.

METHODS

An analysis of 194 patients having thyroidectomy and simultaneous parathyroid autotransplantation at Barnes Hospital from 1990 to 1994 was performed. Data were collected regarding patient demographics, indication for thyroidectomy, operative procedure, pathologic diagnoses, and postoperative course, including biochemical assessment of parathyroid autograft function.

RESULTS

Of 194 patients having either total, subtotal, or completion thyroidectomy, 104 (54%) experienced a [Ca(+2)]nadir less than or equal to 8.0 mg/dL and had symptoms and signs of hypocalcemia. Parathyroid autotransplantation was successful in 103 (99%) of these 104 cases and resulted in a 1.0% incidence of hypoparathyroidism in this series.

CONCLUSIONS

Although preservation of parathyroid glands in situ is desirable, routine parathyroid autotransplantation during thyroidectomy virtually eliminates postoperative hypoparathyroidism. Normal parathyroid glands resected or devascularized during thyroidectomy for well-differentiated thyroid carcinoma or benign disease should be transplanted in the sternocleidomastoid muscle. Patients with Multiple Endocrine Neoplasia type 2A should have parathyroid glands resected at the time of thyroidectomy for medullary thyroid carcinoma and transplanted in the nondominant forearm. Postoperative management in most patients after thyroidectomy and parathyroid autotransplantation involves temporary calcium and vitamin D replacement and close biochemical evaluation. This precautionary measure of parathyroid autotransplantation markedly reduces the incidence of permanent postoperative hypoparathyroidism.

Metastatic papillary thyroid carcinoma presenting as a typical branchial cyst

Two cases of papillary thryoid carcinoma presenting as a cystic lateral neck mass are reported. This tumour characteristically presents in patients under 40-years-old and in the presence of an occult primary tumour may mimic a branchial cyst. In such cases simple aspiration of the cyst will produce a chocolate-brown serous fluid which excludes the diagnosis of a branchial cyst and is characteristic of papillary thyroid carcinoma. Cytological examination of the fluid has a high degree of sensitivity and specificity in the diagnosis of thyroid malignancy and should avoid delay in diagnosis and unnecessary surgical exploration prior to definitive treatment.

Surgical considerations and approach to thyroid cancer

Patients with thyroid cancer can be safely treated by an experienced endocrine surgeon. More extensive initial surgery such as total or near-total thyroidectomy seems to decrease tumor recurrence and prolong life. When such operations can be done with minimal complications, we believe it is the treatment of choice because even low-risk patients have a 4% or 5% risk of eventually dying of thyroid cancer. If this risk of death from thyroid cancer can be decreased to 1% or 2% and the rate of serious complications is 1% or 2%, the authors believe total thyroidectomy is indicated. Most patients can be discharged within 1 day of total thyroidectomy.

A twenty-year experience with thyroid carcinoma in children

During the past 20 years, 23 patients (7 males, 16 females) were operated on for thyroid carcinoma in our institution. The average age was 13.6 years (range, 22 months to 27 years). Our series includes papillary carcinoma in 11, follicular carcinoma in four, and medullary thyroid carcinoma in eight patients. Follow-up ranged from 8 months to 20.3 years, with an average of 7.5 years for well-differentiated carcinomas and 4.3 years for medullary thyroid carcinomas. All patients are presently alive with no evidence of progressive disease. Patients with papillary and follicular carcinomas underwent partial thyroidectomy; those with medullary carcinoma underwent total thyroidectomy. Serious complications included three permanent hypoparathyroidism and two tracheostomies, all after secondary neck explorations. The overall results observed in our series of patients seem to support the current conservative approach to well-differentiated thyroid carcinoma, reserving total thyroidectomy for medullary cancer of the thyroid. A more aggressive search for familial medullary carcinoma through use of pentagastrin stimulation leads to early detection and more effective therapy.

Thyroid cancer: the case for total thyroidectomy

Since there are no prospective studies concerning the treatment of thyroid cancer, there continues to be a considerable disagreement about the 'best' or most appropriate form of surgical treatment for patients with papillary or follicular thyroid cancer. Some surgeons recommend selective treatment depending upon the type of thyroid tumor and stage of the disease. Some advocate thyroid lobectomy and isthmusectomy, some near total thyroidectomy, and some total thyroidectomy for patients with papillary and follicular thyroid cancer. Total thyroidectomy for thyroid cancer would be the treatment of choice for virtually all patients with thyroid cancers if it could be done without complications. We therefore reviewed 160 consecutive patients who had total thyroidectomy for suspected or proven thyroid cancer to determine the complication rate of total thyroidectomy. One hundred and three patients had primary operations, 57 had reoperations with completion of total thyroidectomy and 124 had thyroid cancer. Serious complications (i.e. vocal cord paralysis or hypoparathyroidism) included two cases of transient bilateral recurrent nerve palsy, two patients with presumed transient unilateral vocal cord paralysis, three recurrent laryngeal nerves that were purposely sacrificed because of invasion of the nerve, and one case of permanent hypoparathyroidism. Two other patients developed postoperative wound infections. Only one of the permanent complications, the case of permanent hypoparathyroidism, could have been avoided by a lesser procedure. The experienced surgeon can perform a total thyroidectomy with minimal morbidity, and this procedure has certain theoretical and practical advantages. It should not be done, however, if it will result in a significant complication rate and, in selected patients, it may be preferable to leave a small amount of thyroid tissue to protect the blood supply to the parathyroid glands or recurrent laryngeal nerve.

Papillary thyroid cancer treated at the Mayo Clinic, 1946 through 1970: initial manifestations, pathologic findings, therapy, and outcome

We performed a retrospective study of 859 patients with papillary thyroid cancer, who had received their primary treatment at the Mayo Clinic during the period 1946 through 1970. The maximal follow-up was 39 years. All but 2 patients underwent a thyroid operation; 319 (37%) had metastatic cervical nodes. Of the 800 patients without distant metastatic lesions on initial examination who underwent a potentially curative surgical procedure, postoperatively 7% had nodal metastatic lesions, 6% had a local tumor recurrence, and 5% had a distant metastatic lesion. In patients who had intrathyroidal tumors initially, postoperative local recurrences or distant metastatic lesions resulted in a 10-year cancer mortality of 17 and 41%, respectively; in those with extrathyroidal tumors, postoperative recurrences were associated with significantly higher death rates. Death from thyroid cancer was highly associated with the following factors: age more than 50 years, male sex, tumor size, tumor grade, initial extent of disease, and absence of Hashimoto's disease. Earlier studies of Mayo patients treated between 1926 and 1960 described no deaths due to thyroid cancer in patients with occult tumors (1.5 cm or less). Four such patients were identified among our 859 patients; all had been examined and treated after 1961. To date, 56 (6.5%) of the 859 patients have died as a result of papillary thyroid cancer. In this study, in which 16% of patients underwent total thyroidectomy and 3% had radioiodine ablation, the overall mortality observed at 30 years was only 3% above that expected.

Total thyroidectomy. A review of 213 patients

During a 10.5-year period ending in June 1982, total thyroidectomy was performed on 213 patients at the Vanderbilt University Medical Center. A nonfunctioning nodule on technetium scan was the primary indication for operation. Twenty-one of 213 patients had undergone previous partial thyroidectomy. The pathologic changes in the excised thyroids were carcinoma (81 patients), thyroiditis (27 patients), multiple benign adenoma (16 patients), thyrotoxicosis (27 patients), multinodular goiter (56 patients), and C-cell hyperplasia (three patients). Three total thyroidectomies were performed in search of a parathyroid adenoma. Fourteen patients had coexistent primary hyperparathyroidism. Excluding 12 patients with medullary carcinoma, 25% of all other patients with carcinoma would have had unrecognized tumor left in the remaining lobe had a total thyroidectomy not been performed. Calcium supplements were required in 59 patients during hospitalization, but only 2.8% of the patients developed permanent hypoparathyroidism. Since the adoption of Thompson's technique of total thyroidectomy, only one of the 128 patients (0.8%) has sustained permanent hypoparathyroidism. Two patients exhibited transient recurrent laryngeal nerve palsies without permanent nerve damage. There were no operative deaths. The low morbidity of total thyroidectomy appears to justify its use in all patients with differentiated thyroid malignancy. With surgeons experienced in this technique, total thyroidectomy should also be considered as the primary treatment for many other patients requiring thyroidectomy.

The solitary thyroid nodule: diagnosis and management of malignant disease

While few solitary thyroid nodules are carcinomatous, it is essential to identify and preferentially select those that are for surgery. Clinical, biochemical, serologic, radiographic, scintigraphic, sonographic, biopsy, and even therapeutic evaluation may be necessary to choose those patients with the greatest probability of malignancy. The benefits and limitations of each diagnostic modality are discussed, and the importance of fine-needle aspiration is stressed. After the operative confirmation of malignancy, the prognosis in any given case depends on 1) the histologic type of the neoplasm, 2) its size and extent, 3) the presence of angioinvasiveness, 4) the tendency toward multicentricity of the lesion, 5) the age and sex of the patient, and 6) whether distant metastases are present. These factors influence the extent of surgery required for well-differentiated carcinomas. Meticulous dissection and preservation of the recurrent laryngeal nerves and the parathyroid glands along with their blood supply are important if total thyroidectomy for papillary carcinoma is to be employed with an acceptable operative morbidity to optimize survival. The value of the adjunctive use of thyroid hormone and radioactive iodine is also discussed. Finally, the clinical behaviors and treatments of undifferentiated carcinomas, sarcomas, lymphomas, and neoplasms metastatic to the thyroid gland are reviewed.

Total thyroidectomy: the treatment of choice for patients with differentiated thyroid cancer

There is considerable controversy about the most appropriate treatment of patients with thyroid cancer. This report concerns the author's experience with 82 consecutive patients having total thyroidectomy from January 1977 through December 1981. The age of the patients ranged from 21 to 86 years (mean age 44 years). There were 44 women and 38 men. Twenty-four patients (29%) had had previous thyroid operations; ten patients (11%) had coexistent parathyroid adenomas removed; and seven patients (8.5%) had modified radical neck dissections. Thirty-four patients (41%) had a history of radiation to the head and neck, and 12 (35%) of the 34 irradiated patients and 51 (63%) of the entire group of 82 patients had thyroid cancer (45 papillary, five follicular, one medullary). Coexistent lesions in the patients with papillary cancer included Hashimoto's thyroiditis, five patients; parathyroid adenomas, four patients; Graves' disease, one patient; Hurthle cell neoplasm, one patient; and amyloid struma, one patient. If less than total thyroidectomy had been performed, 26 (51%) of the 51 patients with thyroid cancer would have had cancer left in the residual thyroid lobe, and focal cancers in the lobe opposite to the one containing the nodule for which the operation was performed would have been missed in five patients (10%). Five of the 20 patients with unilateral cancer had follicular cancer. Complications included one case of permanent hypoparathyroidism and two cases of transient bilateral recurrent laryngeal nerve palsy. Ninety-six per cent of the patients were discharged within four days of thyroidectomy, 94% by three days, and 79% by two days. Uptake of radioactive iodine was not above background levels in nine (26%) of the 35 patients studied after operation and was less than 1% in the remainder. These data suggest that total thyroidectomy is the treatment of choice for patients with thyroid cancer because residual cancer would persist in the remaining thyroid tissue in at least 61% of patients if only lobectomy had been performed. Total thyroidectomy can be done with minimal permanent disability in patients with benign and malignant thyroid tumors, in patients who have had previous thyroid operations, and in patients with coexistent hyperparathyroidism.

Needle biopsy in the assessment and management of hypofunctioning thyroid nodules

Needle biopsy of hypofunctioning solitary thyroid nodules provides direct diagnostic information which would be otherwise obtainable only by surgery. The technique is safe and cost-effective. It provides a high diagnostic yield. It is also useful in planning surgery and reducing dependence on frozen-section diagnosis, which is often difficult with thyroid nodules. Technical and interpretative precautions are discussed. Of 192 patients undergoing this procedure, a satisfactory specimen was obtained in 95 percent. Needle aspiration biopsy (fine needle) was done in 110 patients with good cytologic correlations. Of 52 glands subsequently excised, carcinoma was present in 22 (42 percent). The preoperative diagnosis had been made in 19 (86 percent) of the latter group. This procedure is recommended for consideration in the assessment and management of hypofunctioning thyroid nodules.

Treatment of locally invasive carcinoma of the thyroid: how radical?

Forty-seven patients with locally invasive thyroid carcinoma were treated at the M.D. Anderson Hospital over a 10 year period. The factors that adversely affected their survival included age, male sex, spindle and giant cell histology, and extensive involvement of adjacent structures in the neck. Surgical treatment aimed at removal of all gross tumor with preservation of vital structures whenever possible offers a reasonable chance of cure in locally aggressive well-differentiated thyroid cancer. Extensive ablative procedures are rarely indicated and do not improve survival. Radioactive iodine is beneficial in the treatment of well-differentiated lesions.