Follow-up of patients with differentiated thyroid carcinoma. Experience at Institut Gustave-Roussy, Villejuif

Autosomal dominant polycystic kidney disease: a potential mistake in the interpretation of radioiodine whole-body scintigraphy

There are a few case reports of renal cysts demonstrating radioiodine uptake on scintigraphy. In this case, we report a 49-year-old man who had undergone total thyroidectomy and had been treated with radioiodine. After conventional levothyroxine withdrawal, the patient underwent thyroid remnant ablation by oral administration of 125 mci ¹³¹I. Seven days later, post-therapy whole-body scan demonstrated thyroid remnant tissue and bilaterally multifocal radioiodine uptake in the upper abdomen. By ultrasonography and abdominal computed tomography scan, the iodine uptake was proven to be due to the accumulation of ¹³¹I in bilateral polycystic kidney disease.

Clinical significance of residual occult malignancy in thyroid carcinoma

PURPOSE

Total or near-total thyroidectomy is advocated in reducing the recurrence rate and improving survival in differentiated thyroid carcinoma. However, this potential benefit could be seen in all patient groups or only in the patients who have multifocal disease. We analyzed the clinical significance of occult multifocal disease in patients with completion thyroidectomy.

PATIENTS AND METHODS

Ninety-seven patients in whom the completion thyroidectomy was performed within 6 months were included. The patients were grouped according to whether they have malignancy in the remnant thyroid tissue. The groups were examined and compared according to patients and tumor characteristics. The effect of the presence of residual tumor in remnant thyroid tissue on clinical course, disease-free survival, and overall survival were evaluated as well.

RESULTS

After completion thyroidectomy, 20 (20.6%) of the 97 patients revealed additional cancer focus in the residual tissue. Median follow-up period was 104 months (range, 84-205 months). Only tumor multifocality in the resected lobe after first surgery was predictive of the presence of malignancy in the thyroid remnant (P = .002; relative risk, 4.9; 95% confidence interval, 1.7-14.5). Detection of malignancy in the remnant thyroid tissue did not affect the disease-free survival (P = .39). There were no deaths in patients who underwent reoperative thyroid surgery.

CONCLUSIONS

Only tumor multifocality in the original thyroid lobe was predictive of finding additional cancer in the contralateral lobe. However, clinical significance of occult multifocal disease was not shown.

Diagnostic value of serum thyroglobulin measurements in the follow-up of differentiated thyroid carcinoma, a structured meta-analysis

OBJECTIVE

To investigate to what extent thyroid remnant ablation and withdrawal from thyroxine are required to achieve sufficient accuracy of serum thyroglobulin (Tg) measurements as an indicator of tumour recurrence in the follow-up of patients with differentiated thyroid carcinoma.

DESIGN AND METHODS

We conducted a meta-analysis of the literature from 1975 to 2003 on serum Tg measurements in the follow-up of differentiated thyroid carcinoma. In a computer-based search, we initially found 915 articles that were finally narrowed down to 120. These 120 papers were subjected to strict in/and exclusion criteria, leaving 46 articles (totalling 9094 patients). Data from these articles were extracted in a structured fashion and were grouped according to initial therapy, TSH status, Tg assay method and definition of a 'gold standard'. Original 2 x 2 tables were pooled by summary receiver operating characteristic curve analysis (sROCa), best estimates of sensitivity and specificity being obtained by the combination of sROCa and Mantel-Haenszel odds ratios.

RESULTS

Despite considerable differences between series in laboratory and clinical methodology, we consistently found higher specificity for Tg measurements after thyroid remnant ablation than after surgery alone. Highest pooled sensitivity 0.961 +/- 0.013 (SE) was found for immunometric assay (IMA) after thyroid remnant ablation and thyroid hormone withdrawal, at a specificity of 0.947 +/- 0.007. Pooled sensitivity decreased significantly if ablated patients were tested while on thyroid hormone (0.778 +/- 0.023, at a specificity of 0.977 +/- 0.005). Significantly decreased pooled specificity was found in patients who did not undergo remnant ablation (sensitivity 0.972 +/- 0.023, at a specificity of 0.759 +/- 0.028). If recombinant human TSH (rhTSH) stimulation was used as a substitute for thyroxine withdrawal, sensitivity remained high (0.925 +/- 0.018) while specificity decreased to 0.880 +/- 0.013. In all analyses, specificity of Tg would decrease when unspecified activity in the thyroid region at scintigraphy was considered benign, whereas sensitivity decreased when such activity was considered malignant.

CONCLUSION

This study confirms that the best accuracy of Tg-guided follow-up in patients treated for differentiated thyroid carcinoma is obtained if treatment includes remnant ablation, and Tg testing is performed while off thyroxine.

[Principles of lymph node surgery in differentiated thyroid carcinoma]

Surgery is the initial therapy in differentiated thyroid carcinoma (DTC). The surgery is performed on organ of tumor origin and regional lymphatic basins. The aim of surgery in DTC is to eradicate all tumor foci, cure the most number of patients, reduce recurrence and mortality rate, and provide good quality of life. There is no doubt between oncologists that the surgery for thyroid carcinoma has no alternative. The extent of surgery is matter of actual controversies. It should be performed by well trained surgeons. Dissection of central and biopsy of supraclavicular and lower third of jugulo-carotid chain of neck lymph nodes is the integral part of surgery in DTC, together with total thyroidectomy. If lymph node metastases are found in jugulo-carotid chain, modified radical neck dissection, unilateral or bilateral is indicated. Dissection of mediastinal lymph nodes should be performed too in cases of involvement. The extent of primary surgery should be dictated by stage of disease and prognostic factors. The quality of surgery and incidence of complications depends prognostic factors, as well as on surgeon's skill and experience. That is why the surgeon is factor of prognosis in treatment of patients with DTC.

[Identification of sentinel lymph nodes in thyroid carcinoma]

Sentinel lymph node (SLN) was defined as the first lymph node that the tumor would drain to, within that tumors regional lymphatic basin. In 1998, Kelemen and coworkers have published the first results on SLN lymphonodectomy in thyroid carcinomas. Different methods have been used in a goal of lymphatic mapping (application of vital blue dye and/or radiocolloid). In a period from 2001 to 2003 we have performed SLN biopsy in 64 patients with thyroid tumors. There were 12 cases of thyroid carcinoma. SLN identification rate was 73.44%. We found no false positive or negative results on definitive histopathology. The impact of lymph node metastases in differentiated thyroid carcinoma is still controversial. The management of cervical lymph nodes varies from berry picking to modified radical neck dissection. There is a significant disproportion in percentage of pre and intraoperatively enlarged lymph nodes (27-45%) and histologically confirmed lymph node metastases (80-90%) in papillary thyroid carcinoma. In the current literature the average rate of SLN identification is 91% (66-100%) and when identified, the SLN accurately predicts the disease status of the neck in most patients (80-100%). The SLN biopsy for thyroid carcinoma is good and feasible technique for estimating the cervical lymph node status.

Role of metastasectomy in the management of thyroid carcinoma: the NIH experience

BACKGROUND AND OBJECTIVES

We studied the impact of metatasectomy on disease outcome in 29 advanced nonmedullary thyroid carcinoma (ThyrCa) patients who were operated on between 1969 and 2001 at NIH to further define its role in the management of this malignancy.

METHODS

Data were extracted by retrospective chart review. A Kaplan-Meyer survival curve was constructed, and comparative stratification for various parameters was performed.

RESULTS

During 47 surgeries, the following lesions were resected from mid-mediastinum/hila, 17; lung parenchyma, 12; skeleton, 14; kidneys, 2; and brain, 2. All patients received multiple radioiodine (RAI) treatments. External-beam radiotherapy, chemotherapy and other palliative measures were used in selected patients. Six patients (21%) died within 74.7 +/- 54.7 months after the first distant metastasectomy. The outcome of the remaining patients was as follows: complete remission, 3; partial remission, 10; and 10: progressive disease, 10, with a follow-up of 175 patient-years. Metastasectomy led to a decrease of 38% in thyroglobulin levels in 23 patients. Cumulative survival rates were 78.5 +/- 8.4% at 5 years and 50.2 +/- 12.5% at 10 years (mean +/-SEM) after initial distant metastasectomy.

CONCLUSIONS

Our data show that extensive targeted metastasectomy in the setting of a tertiary center can be beneficial to patients with disseminated ThyrCa with persistent or recurrent distant disease, when used in conjunction with nonsurgical treatment modalities.

Death from differentiated thyroid carcinoma: retrospective study of a 40-year investigation

Differentiated thyroid carcinoma (DTC) usually has a good prognosis, but sometimes the course of the disease results in death. The aim of the present study was to assess the effect of some variables in time to death on fatal cases in our series. A total of 83 patients with DTC who died between 1958 and 1998 from differentiated thyroid cancer were retrospectively analyzed with respect to gender, age at diagnosis, histology, percentage of (131)I uptake by postoperative thyroid remnant, site of tumor growth, and its (131)I uptake, metastases and time to death. Univariate analysis revealed a significantly shorter time to death in local recurrence when comparing local lymph node metastases and distant metastases even if neither show (131)I uptake. Multivariate analysis revealed that age at diagnosis was the most important factor in conditioning the time to death. In conclusion, in those patients who died from DTC an older age at diagnosis and presence of local recurrence influenced the time to death independently of (131)I uptake.

The use of recombinant human TSH in the follow-up of differentiated thyroid cancer: experience from a large patient cohort in a single centre

BACKGROUND

Periodic evaluation of serum thyroglobulin (Tg) and whole body 131I imaging (131I-WBS) are essential in the follow-up of differentiated thyroid carcinoma (DTC); both diagnostic modalities require stimulation by high levels of TSH. Administration of recombinant human TSH (rhTSH) is an alternative to the withdrawal of thyroid hormone therapy.

OBJECTIVE

The aim of this study was to report our experience in the use of rhTSH for the management of patients with DTC.

PATIENTS

One hundred and four patients were enrolled in the study. A dose of 10 U of rhTSH therapy was injected intramuscularly for 2 consecutive days; 24 h after the second dose of rhTSH the patients were administered 4--5 mCi of 131I and, 48 h later, WBS was performed.

RESULTS

In all patients, baseline mean serum Tg and TSH levels were 2.4 +/- 1.9 ng/ml and 0.0153 +/- 0.0232 mIU/l, respectively. Basal Tg levels were detectable in 58 out of 104 patients. After rhTSH injection, mean serum TSH levels rose to 122.67 +/- 47.36 mIU/l. Stimulated serum Tg levels increased to greater-than-or-equal 5 ng/ml and the 131I-WBS showed an uptake in 18 patients (17.4%). Among them there were three with bone metastases and one with brain metastases, who reported violent skeletal pain and a severe headache, respectively. These were caused by the growth of tumour mass of metastases induced by rhTSH administration.

CONCLUSIONS

The use of rhTSH avoids the debilitating effects of hypothyroidism and its use successfully promotes iodine uptake and increases the sensitivity of serum Tg testing. The risk of causing serious side-effects recommends performing skull magnetic resonance and radionuclide bone scan in cases of suspected brain or skeletal metastases.

Recurrent differentiated thyroid cancer without elevation of serum thyroglobulin

Thyroglobulin (Tg) is a reliable tumor marker in patients with well-differentiated thyroid cancer (WDTC). We identified 11 patients who had undetectable serum Tg and no thyroglobulin antibody (TgAb) in the presence of clinical disease. Three had residual disease after ablation of the thyroid by surgery plus radioiodine and 8 relapsed after a disease-free interval. Histologic review confirmed that 7 of the tumors were papillary carcinomas and 4 were follicular carcinomas. Immunohistochemical staining for Tg was positive in 6 of 7 papillary and in 3 of 4 follicular carcinomas. There were no identifiable histologic or clinical features that could be used to predict further patients who may relapse with absence of this serum marker. Negative serum Tg did not appear to be an adverse prognostic feature. During follow-up, measurement of Tg and TgAb should be supplemented by radioiodine scanning and radiological imaging in patients in whom recurrence is likely or suspected.

High-resolution ultrasound associated with aspiration biopsy in the follow-up of patients with differentiated thyroid cancer

OBJECTIVE: To assess the value of ultrasound in the follow-up of patients undergoing surgery for differentiated thyroid carcinoma.

SUBJECTS: The study included 89 patients (70 women and 19 men) with differentiated thyroid carcinoma (76 papillary and 13 follicular cancer).

METHODS: High-frequency ultrasound (US) was used in the evaluation of 89 subjects who underwent surgery for thyroid carcinoma. Fine-needle aspiration was performed in cases with positive US. In addition, determinations of thyroglobulin (Tgb) in serum, scintigraphy with 131I, and cervical palpation were evaluated. We determined sensitivity, specificity, and overall accuracy for each of these diagnostic methods.

RESULTS: Ultrasonography was positive in 22 subjects, 16 in the nodal area and 6 in the thyroid bed. Twenty-two subjects received fine-needle aspiration with US control; 13 (59%) of 22 were positive for cancer. The results of the US for detecting neoplastic disease showed a sensitivity of 65%, specificity of 86%, and overall accuracy of 82%. The overall accuracy for scintigraphy was 88% and for Tgb, 91%.

CONCLUSION: We concluded that US can be included in the follow-up protocol for patients undergoing surgery for differentiated cancer of thyroid, as a valuable tool to localize the recurrence. This technique is particularly useful in the evaluation of patients who are found to have elevated Tgb levels.

The treatment of differentiated thyroid cancer includes surgery and, in some cases, the ablation of residual thyroid tissue with therapeutic doses of iodine 131I. 1 The posttreatment search for recurrence or metastases is based on periodic body scanning with 131I and determination of serum thyroglobulin (Tgb) levels. 2,3

High-resolution ultrasound (US; 10 MHz) has been found to have a high sensitivity in diagnosing nonpalpable cervical masses. 4–6 Thus the possibility exists that including it in the protocols for follow-up of differentiated thyroid cancer may be valuable.

The aim of our study was to assess the value of high-resolution US (associated with directed fine-needle aspiration [FNA] biopsy) in the follow-up of patients undergoing surgery for papillary and follicular thyroid cancer.

False positive 131I total body scan due to bilateral polycystic renal disease

A radioiodine accumulation at Total Body Scan (TBS) in patient who has been thyroidectomized for a differentiated thyroid cancer is usually a reliable indicator of recurrent or metastatic functioning thyroid tissue. Radioiodine uptake may be usually observed at TBS in areas such as the intestinal tract, liver, salivary glands, bladder, and also in case of blood vessel ectasia. This report describes a patient with a bilaterally significant 131I uptake in upper abdomen. By ultrasound and radionuclide imaging the 131I uptake was proven to be due to radioiodine accumulation caused by bilateral polycystic renal disease.

Thyroid cancer: a review of treatment and follow-up

The importance of thyroid cancers far exceeds their frequency, since they are uncommon tumours accounting for only 1% of all malignancies and for even smaller proportion of cancer deaths (0.2%). A variety of distinct tumour types arise in the thyroid gland, with variable natural histories resulting from different rates of growth and biological aggressiveness. The long natural history of the majority of thyroid neoplasms imposes a commitment for long-term follow-up and stresses the importance of planning treatment so as to avoid delayed complications that impair the quality of life of patients. The management of thyroid cancer is multidisciplinary, requiring consultation and active intervention by surgeons, endocrinologists and radiotherapists. Surgery is of paramount importance in the successful eradication of the tumours while radioiodine offers a unique therapeutic approach. Treatment must be strongly influenced by consideration of prognostic variables.

Completion thyroidectomy for differentiated thyroid carcinoma

Completion thyroidectomy is defined as the surgical removal of the remnant thyroid tissue following procedures less than total or near-total thyroidectomy. The extent of surgical management for differentiated thyroid carcinoma (DTC) is controversial. Although some authors advocate subtotal thyroidectomy with lower complication rates, total or near-total thyroidectomy and completion thyroidectomy have been defended by others because of the improved survival and lower morbidity that is comparable with subtotal thyroidectomy. In this study, the incidence of residual tumor and surgical complication rates in patients who underwent completion thyroidectomy were investigated. The medical records of 165 patients undergoing completion thyroidectomy for DTC were reviewed. Seventy-seven (46.6%) of these patients were found to have residual tumor in the remaining thyroid tissue. Anaplastic transformation developed in two of these patients. Permanent bilateral recurrent laryngeal nerve palsy occurred in three patients, and permanent hypoparathyroidism was seen in one patient. We recommend completion thyroidectomy as an efficient and safe method of surgical treatment with a low complication rate for DTC.

Assessment of the influence of thyroglobulin (Tg) autoantibodies and other interfering factors on the use of serum Tg as tumor marker in differentiated thyroid carcinoma

The purpose of the study was to examine the value of a commercial immunoradiometric (IRMA) method for measuring serum thyroglobulin as a tumor marker after treatment for differentiated thyroid carcinoma. A prospective analysis of consecutive serum samples from 53 patients was performed using the IRMA method and a traditional double antibody radioimmunoassay (RIA). The results were compared with those of 100 healthy control subjects and furthermore the method was validated by investigating sera from 24 patients with Hashimoto's thyroiditis positive for thyroglobulin autoantibodies. Finally, in vitro studies of the influence of thyroglobulin autoantibodies on the method were done. The IRMA method had an acceptable analytical precision and was more sensitive than the RIA. It was furthermore less sensitive to the presence of thyroglobulin autoantibodies but it was affected by them, and it showed less unspecific serum effect. Both methods had limitations as tumor marker when the patients had a thyroid remnant, when serum thyrotropin was not suppressed, and in cases of local recurrence. The highest predictive value was found in patients with distant metastases. Thus, in cases of only slightly elevated serum thyroglobulin, the strongest indication for recurrence is still an increasing serum thyroglobulin level within the same patient rather than a single value.

Endocrinological applications in nuclear medicine

Diagnosis and treatment of thyroid diseases have played a major role in Central European Nuclear Medicine. Since 1950, endocrinological nuclear medicine has been one of the strengths of this medical discipline. Not only diagnosis but also conservative treatment with thyroid depressants or hormones is performed by the nuclear medicine specialists. Nuclear medicine also takes part in the diagnosis of other endocrine diseases. The respective procedures include imaging of the adrenal gland (cortex and medulla) as well as of the parathyroid glands. Especially in the latter diseases, imaging was improved through Tc-99m sestamibi scintigraphy. Beyond that, the measurement of bone mineral content contributes to the full spectrum of endocrinological nuclear medicine. The development of In-111 octreotide now plays a limited role in the diagnosis of diseases of the pituitary gland.

False positive 131I total body scan due to an ectasia of the common carotidis

A cervical accumulation of radioiodine at Total Body Scan (TBS) in a patient who had been thyroidectomized for a follicular thyroid carcinoma led to unnecessary radioiodine treatment. Thyroglobulin measurements indicated constantly low levels. Following ultrasound scanning of the neck, echo-doppler examination of the cervical vessels and angiography with 99Tc, this area of increased activity at TBS imaging was shown to be due to an ectasia of the right common carotidis causing blood stasis and reverse flow.

A new immunoradiometric assay (IRMA) system for thyroglobulin measurement in the follow-up of thyroid cancer patients

A new commercially available kit for thyroglobulin (Tg) measurement [immunoradiometric assay (IRMA) system based on monoclonal antibodies] was used in 479 patients with thyroid carcinoma. The effective working range was 1 ng/ml, and results were strongly correlated with our homemade radioimmunoassay (RIA). This IRMA method is less susceptible to interferences of auto-antibodies than our RIA. During thyroxine (T4) treatment, the Tg level was undetectable in 98% of patients after total thyroid ablation, in 91% after total thyroidectomy and in 42% after lobectomy only. In this situation, Tg was found in all patients with large metastases and in 88% of those with small metastases. Following T4 withdrawal, Tg was detectable in all patients with neoplastic disease and in 13% of those in complete remission after total thyroid ablation. In conclusion, Tg measured with this IRMA method appears to be a reliable marker of differentiated thyroid carcinoma.

The clinician and the thyroid

The goiter prevalence in iodine-deficient regions is up to 25%-54%. The most frequent disease in these endemic areas is non-toxic goiter, which is, however, oftentimes connected with autonomously functioning thyroid tissue leading to borderline or overt hyperthyroidism. Other thyroid diseases like cancer, thyroiditis and hypothyroidism play only a minor role in a thyroid clinic, while cases of Graves' disease may be observed more frequently. The most cost-effective tools to evaluate thyroid patients are the hand, ear and mouth of the thyroid clinician. The differential diagnosis of thyroid disorders may be evaluated by a battery of diagnostic tools like in-vitro tests and high performance imaging modalities. Once the diagnosis is established, the appropriate therapeutic procedures (drugs, radioiodine, surgery) have to be chosen. This review should be considered as a guideline for the diagnosis and treatment of thyroid diseases. In addition, special problems concerning elderly patients and pregnant women are discussed, including the differential diagnosis of thyroid diseases.

Effective laboratory evaluation of thyroid status

This article focuses on recent developments in thyroid-related laboratory tests, including analytical methods, clinical utility, and limitations of TSH, FT4, T4, FT3/T3, thyroglobulin, and thyroid autoantibodies and the effective use of these tests in the diagnosis of various forms of hypothyroidism or hyperthyroidism, and the management of patients undergoing T4 replacement, T4 suppression, or antithyroid drug therapy.