NONINVASIVE FOLLICULAR TUMOR WITH PAPILLARY-LIKE NUCLEAR FEATURES: NOT A TEMPEST IN A TEAPOT.

OBJECTIVE: Encapsulated non-invasive follicular variant papillary thyroid cancer (ENIFVPTC) has recently been retermed noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP). This designation specifically omits the word "cancer" to encourage conservative treatment since patients with NIFTP tumors have been shown to derive no benefit from completion thyroidectomy or adjuvant radio-active iodine (RAI) therapy. METHODS: This was a retrospective study of consecutive cases of tumors from 2007 to 2015 that met pathologic criteria for NIFTP. The conservative management (CM) group included patients managed with lobectomy alone or appropriately indicated total thyroidectomy. Those included in the aggressive management (AM) group received either completion thyroidectomy or RAI or both. RESULTS: From 100 consecutive cases of ENIFVPTC reviewed, 40 NIFTP were included for the final analysis. Of these, 10 (27%) patients treated with initial lobectomy received completion thyroidectomy and 6 of 40 (16%) also received postsurgical adjuvant RAI. The mean per-patient cost of care in the AM group was $17,629 ± 2,865, nearly twice the $8,637 ± 309 costs in the CM group, and was largely driven by the cost of completion thyroidectomy and RAI. CONCLUSION: The term NIFTP has been recently promulgated to identify a type of thyroid neoplasm, formerly identified as a low-grade cancer, for which initial surgery represents adequate treatment. We believe that since the new NIFTP nomenclature intentionally omits the word "cancer," the clinical indolence of these tumors will be better appreciated, and cost savings will result from more conservative and appropriate clinical management. ABBREVIATIONS: AM = aggressive management CM = conservative management ENIFVPTC = encapsulated noninvasive form of FVPTC FVPTC = follicular variant of papillary thyroid carcinoma NIFTP = noninvasive follicular thyroid neoplasm with papillary-like nuclear features PTC = papillary thyroid carcinoma PTMC = papillary thyroid microcarcinoma RAI = radio-active iodine US = ultrasound.

Frequency of High-Risk Characteristics Requiring Total Thyroidectomy for 1-4 cm Well-Differentiated Thyroid Cancer.

BACKGROUND: The extent of thyroidectomy for low-risk well-differentiated thyroid cancer (WDTC) remains controversial. Historically, total thyroidectomy (TT) has been recommended for WDTC ≥1 cm in size. However, recent National Comprehensive Cancer Network and American Thyroid Association guidelines recognize unilateral thyroid lobectomy as a viable alternative for 1-4 cm cancers due to their otherwise favorable prognosis, with TT remaining the preferred option for tumors with unfavorable pathological characteristics. This study sought to determine how often a completion TT would be recommended based on these guidelines if lobectomy was initially performed in patients with 1-4 cm WDTC without preoperatively known risk factors. METHODS: Patients who underwent thyroidectomy for 1-4 cm WDTC (January 2000 to January 2010) were retrospectively reviewed. Patients with preoperatively known high-risk characteristics, including gross extrathyroidal extension (ETE) on preoperative imaging, clinically apparent lymph node metastases, distant metastases, history of radiation, and positive family history, were excluded. The pathology specimens from the cancer-containing lobe were evaluated for features that would lead to a recommendation for TT based on current guidelines, including aggressive histology, vascular invasion, microscopic ETE, positive margins, and any positive lymph nodes within the specimen. RESULTS: Of 1000 consecutive patients operated for WDTC, 287 would have been eligible for lobectomy as the initial operation. The mean age in this cohort was 45 years, and 80% were women. Aggressive tall-cell variant histology was found in one patient (0.5%), angio-invasion in 34 (12%), ETE in 48 (17%), positive margins in 51 (18%), and positive lymph nodes in 49 (18%) patients. Completion TT would have been recommended in 122/287 (43%) patients. Even in those with 1-2 cm cancers, completion TT would have been recommended in 52/143 (36%) patients. CONCLUSIONS: Nearly half of the patients with 1-4 cm WDTC who are eligible for lobectomy under current guidelines would require completion TT based on pathological characteristics of the initial lobe. Surgeons, endocrinologists, and patients need to balance the relative benefits, risks, and costs of initial TT versus the possible need for reoperative completion TT.

Radioiodine ablation with 1,850 MBq in association with rhTSH in patients with differentiated thyroid cancer.

PURPOSE: The aim of this study was to evaluate the efficacy of post-operative radioiodine ablation with 1,850 MBq after recombinant human thyrotropin (rhTSH) administration in patients with differentiated thyroid carcinoma (DTC). We also aimed to assess the prognostic role of several patient features on the outcome of ablation. METHODS: We retrospectively analyzed data from a total of 125 patients with DTC who underwent post-operative radioiodine ablation with 1,850 MBq of ¹³¹I after preparation with rhTSH. One injection of 0.9 mg rhTSH was administered on each of two consecutive days; ¹³¹I therapy was delivered 24 h after the last injection, followed by a post-therapy whole-body scan. Successful ablation was assessed 6-12 months later and defined as an rhTSH-stimulated serum thyroglobulin (Tg) level ≤1.0 ng/ml and a normal neck ultrasound. RESULTS: Patients were stratified according to the American Thyroid Association (ATA) Management Guidelines for Differentiated Thyroid Cancer. Successful ablation was achieved in 82.4 % of patients, with an ablation rate of 95.1 % in low-risk patients and 76.2 % in intermediate-risk patients. Analyzing the correlation between ablation outcome and patient characteristics, we found a statistically significant association between failure to ablate and class of risk based on ATA guidelines (p = 0.025) and a stimulated Tg value at ablation of above 5 ng/ml (p < 0.001). CONCLUSION: The use of 1,850 MBq post-operative radioiodine thyroid remnant ablation in association with rhTSH is effective for low- and intermediate-risk patients. Moreover, in our study, we found a statistical correlation between failure to ablate and class of risk based on ATA guidelines for DTC and a stimulated Tg value at ablation.

Impact of early vs late postoperative radioiodine remnant ablation on final outcome in patients with low-risk well-differentiated thyroid cancer.

OBJECTIVE: Postoperative radioiodine remnant ablation (RRA) represents an adjunctive therapeutic modality in patients with differentiated thyroid cancer (DTC). The impact of late vs early RRA on the outcome of DTC is currently unclear. The aim of the study was to evaluate the outcome of patients with DTC according to RRA timing. DESIGN RETROSPECTIVE STUDY PATIENTS: A total of 107 TNM stage 1 DTC patients were divided into two groups. In group A (n = 50), RRA was administered in less than 4·7 months median 3·0 (range 0·8-4·7), while in group B (n = 57) in more than 4·7 months median 6 (4·8-30·3) after thyroidectomy. Remission was achieved when stimulated serum Tg levels were undetectable, in the absence of local recurrence or cervical lymph node metastases on the neck ultrasound. RESULTS: All patients underwent near-total thyroidectomy. The mean age at diagnosis was 49·3 years (range: 18-79 years). There were no statistically significant differences in the histological subtype, the TNM stage, the dose of radioiodine and the time of follow-up, between the two groups. After the RRA treatment, 44 group A patients (88%) were in remission and 6 (12%) in persistence; while in group B, 52 (91·2%) were in remission, 1 (1·8%) in persistence and 4 (7%) in recurrence. At their latest follow-up median 87·3 (23·3-251·6 months), all patients were in remission, either as a result of further iodine radioiodine therapy (in 11 patients) or watchful monitoring. CONCLUSIONS: The timing of RRA seems to have no effect on the long-term outcome of the disease. Therefore, urgency for radioiodine ablation in patients with low-risk thyroid cancer is not recommended.

Optimal surgical management of well-differentiated thyroid cancer arising in struma ovarii: a series of 4 patients and a review of 53 reported cases.

BACKGROUND: Well-differentiated thyroid cancer arising in struma ovarii is rare. The optimal management of this entity remains undefined. Unilateral cystectomy, unilateral salpingo-oophorectomy (USO), or total abdominal hysterectomy with bilateral salpingo-oophorectomy (TAH/BSO), in addition to total thyroidectomy and radioactive iodine (RAI) ablation, have been employed by various groups. We hypothesized that in patients with thyroid cancer arising within struma ovarii, pelvic surgery alone would be sufficient, provided there is no evidence of gross extra-ovarian extension. METHODS: We review a series of four patients from a single institution and 53 cases from the literature, comparing the extent of treatment and outcomes. Our literature review focused on low-risk patients with struma ovarii confined to the ovary, without evidence of gross extra-ovarian spread or distant metastases. Cumulative recurrence rate was determined by using the Kaplan-Meier method. RESULTS: We report the treatment of four patients with well-differentiated thyroid cancer arising within struma ovarii. Patients underwent USO, BSO, or TAH/BSO. One patient underwent prophylactic total thyroidectomy in anticipation of RAI treatment, and was found to have a synchronous papillary thyroid carcinoma. All patients clinically remain without evidence of disease at a median follow-up of 9 (range 0.8-13) years. Treatment strategies in 53 cases from a review of the literature varied. The pooled cumulative recurrence rate of 57 cases with struma ovarii confined to the ovary was 7.5% at 25 years. CONCLUSIONS: Thyroid cancer arising in struma ovarii is rare. Controversy exists regarding the extent of pelvic resection and management of the thyroid gland. In our series of four patients, all patients are alive without evidence of disease, and the 25-year recurrence rate of 57 cases was low (7.5%), despite a variety of approaches to surgical resection and adjuvant treatment. Extensive pelvic surgery and prophylactic total thyroidectomy to facilitate RAI therapy may be reserved for patients with gross extra-ovarian extension or distant metastases.

Metastatic insular thyroid carcinoma in the pediatric patient.

OBJECTIVES: The clinical history of a pediatric patient with metastatic insular thyroid carcinoma will be reviewed. Previously reported cases will be examined to allow for comparison of prognosis. METHODS: A 4-year-old female with the complaint of chronic cough, progressive shortness of breath, and weight loss for 2 months underwent cervical lymph node biopsy. The biopsy revealed metastatic thyroid carcinoma. Preoperative imaging was suspicious for miliary metastatic spread to the lungs. RESULTS: Surgical intervention included total thyroidectomy with bilateral paratracheal and modified radical neck dissections. The right internal jugular vein and recurrent laryngeal nerve were removed at the time of surgery because of gross tumor invasion. Final pathologic finding revealed papillary thyroid carcinoma with insular variant features and bilateral regional metastasis. Postoperatively, the patient underwent radioactive iodine I 131 treatment. CONCLUSION: Pediatric metastatic insular thyroid carcinoma is an uncommon form of thyroid malignancy requiring aggressive surgical treatment and adjuvant radioactive iodine.

The success rate of I-131 ablation in differentiated thyroid cancer: comparison of uptake-related and fixed-dose strategies.

INTRODUCTION: The aim of the study was to compare the success rate of an uptake-related ablation protocol in which the dose depends on an I-131 24-h neck uptake measurement and a fixed-dose ablation protocol in which the dose depends on tumour stage. METHODS: All differentiated thyroid carcinoma patients with M0 disease who had undergone (near-) total thyroidectomy followed by I-131 ablation were included. In the uptake-related ablation protocol, 1100 (uptake >10%), 1850 (uptake 5-10%) and 2800 MBq (uptake <5%) were used. In the fixed-dosage ablation strategy, 3700 (T1-3, N0 stage) and 5550 MBq (N1 and/or T4 stage) were applied. We used I-131 uptake on whole-body scintigraphy and thyroglobulin-off values to evaluate the ablation 6-12 months after treatment. RESULTS: In the uptake-related ablation protocol, 60 out of 139 (43%) patients were successfully treated versus 111 out of 199 for the fixed-dose ablation protocol (56%) (P=0.022). The differences were not statistically significant for patients with T4 (P=0.581) and/or N1 (P=0.08) disease or for patients with T4N1 tumour stage (P=0.937). CONCLUSION: The fixed-dose I-131 ablation protocol is more effective in ablation of the thyroid remnant in differentiated thyroid carcinoma patients than an uptake-related ablation protocol. This difference is not observed in patients with a N1 and/or T4 tumour stage.

An updated systematic review and commentary examining the effectiveness of radioactive iodine remnant ablation in well-differentiated thyroid cancer.

Radioactive iodine remnant ablation (RRA) is used to destroy residual normal thyroid tissue after complete gross surgical resection of papillary or follicular thyroid cancer. The article updates a prior systematic review of the literature to determine whether RRA decreases the risk of thyroid cancer-related death or recurrence at 10 years after initial surgery, including data from 28 studies. No long-term randomized trials were identified, so the review is limited to observational studies. The incremental benefit of RRA in low risk patients with well-differentiated thyroid cancer after total or near-total thyroidectomy who are receiving thyroid hormone suppressive therapy remains unclear.

Total thyroidectomy and adjuvant radioiodine treatment independently decrease locoregional recurrence risk in childhood and adolescent differentiated thyroid cancer.

UNLABELLED: We sought to assess whether extensive surgical treatment, postsurgical radioiodine therapy, or both decrease the risk of locoregional recurrence (LR) after curative primary treatment in children and adolescents diagnosed with differentiated thyroid cancer (DTC) at age

Seminars: controversies in the management of pediatric thyroid malignancy.

Thyroid cancer in children is a rare malignancy with unusual biological behavior. It often presents at advanced stages, yet behaves in a benign manner, when compared to its adult counterpart. Surgeons have debated the risks and benefits of aggressive surgical procedures for over a decade. A consensus treatment plan for childhood thyroid cancer has not been achieved, however radical surgical procedures have, in general, fallen out of favor. The best operative and adjuvant strategy for these children can only be determined when a better understanding of the tumor cell biology and genetics of this cancer is known. This review discusses the current controversies in the management of differentiated childhood thyroid malignancy.

Post-surgical use of radioiodine (131I) in patients with papillary and follicular thyroid cancer and the issue of remnant ablation: a consensus report.

OBJECTIVE: To determine, based on published literature and expert clinical experience, current indications for the post-surgical administration of a large radioiodine activity in patients with differentiated thyroid cancer. DESIGN AND METHODS: A literature review was performed and was then analyzed and discussed by a panel of experts from 13 European countries. RESULTS: There is general agreement that patients with unifocal microcarcinomas = 1 cm in diameter and no node or distant metastases have a <2% recurrence rate after surgery alone, and that post-surgical radioiodine confers recurrence and cause-specific survival benefits in patients, strongly suspected of having persistent disease or known to have tumor in the neck or distant sites. In other patients, there is limited evidence that after complete thyroidectomy and adequate lymph node dissection performed by an expert surgeon, post-surgical radioiodine provides clear benefit. When there is any uncertainty about the completeness of surgery, evidence suggests that radioiodine can reduce recurrences and possibly mortality. CONCLUSION: This survey confirms that post-surgical radioiodine should be used selectively. The modality is definitely indicated in patients with distant metastases, incomplete tumor resection, or complete tumor resection but high risk of recurrence and mortality. Probable indications include patients with tumors >1 cm and with suboptimal surgery (less than total thyroidectomy or no lymph node dissection), with age <16 years, or with unfavorable histology.

Prognostic significance of successful ablation with radioiodine of differentiated thyroid cancer patients.

OBJECTIVES: Currently, little is known about the prognostic significance of achieving successful ablation with the first dosage of I-131 in patients with differentiated thyroid cancer. This study aimed to assess the following: (i) whether successful or unsuccessful ablation at post-ablation follow-up has prognostic consequences; (ii) possible factors predicting success of ablation in a patient. METHODS: In order to do this, we retrospectively studied 180 patients with a median follow-up of 55 months. Ablation was considered to be successful if 1 year after the initial dosage of I-131 patients fulfilled all of the following criteria: not dead from thyroid cancer, no additional therapy needed for any kind for thyroid cancer within the first year, undetectable thyroglobulin (Tg) levels under TSH stimulation, and negative I-131 scintigraphy. Tg levels at the time of ablation (P < 0.001), lymph node metastasis (P = 0.04) and distant metastasis (P < 0.001) have a significant influence on the success of ablation. P values were calculated by Mann-Whitney U test and Chi-square test, respectively. RESULTS: Patients with successful ablation had a better prognosis than those with unsuccessful ablation: disease-free survival was 87% versus 49% after 10 years; additionally, thyroid-cancer related survival was 93% versus 78%. CONCLUSION: We conclude that the extent of the remaining normal or neoplastic thyroid tissue influences the outcome of ablation, and that successful ablation leads to a better prognosis. It seems that it is very important to achieve complete ablation as soon as possible in order to ensure the best possible prognosis for a patient.

Locally advanced thyroid cancer.

PURPOSE OF REVIEW: The purpose of this review is to summarize existing literature with respect to locally advanced thyroid cancer and define the intricacies of preoperative evaluation, surgical management of involved sites and postoperative treatment. RECENT FINDINGS: Locally invasive thyroid cancer is an uncommon disease process, which carries significant morbidity and mortality. Current treatment modalities include appropriate surgery, radioactive iodine treatment and external beam radiation therapy. Proper evaluation of the extent of disease, with complete gross tumor removal, is paramount in managing this difficult problem. Surgical treatment is still the mainstay for locally advanced thyroid cancer. SUMMARY: Little progress has been made in advancing the treatment of locally advanced thyroid cancer. Patient identification, evaluation and proper surgical management with adjuvant therapy, still remain the most effective course of treatment. Aggressive surgical treatment including removal of all gross tumor and still preserving vital structures along with adjuvant therapy is likely to offer the best results. There is a very high incidence of locoregional and distant failure in this group of patients. The understanding and recognition of histopathological variations, such as poorly differentiated thyroid cancer is also important. New molecular markers are needed to help identify and predict aggressive tumor behavior.

131I therapeutic efficacy is not influenced by stunning after diagnostic whole-body scanning.

PURPOSE: To determine if stunning can be seen with a 185-MBq (5-mCi) dose of iodine 131 (131I) at diagnostic whole-body scanning and, if stunning is seen, determine if there is any 131I therapeutic efficacy. MATERIALS AND METHODS: A retrospective review of findings involving 166 patients who underwent thyroidectomy for differentiated thyroid carcinoma was performed. Diagnostic 131I scans were compared with postablation scans for evidence of stunning. Stunning was defined when the diagnostic scan showed activity that was subsequently decreased on the postablation scan. The sample population was divided into two groups: group NS, patients with no stunning, and group S, patients with stunning. Patients were considered successfully treated if no functioning thyroid tissue and/or metastases were seen on follow-up diagnostic scans. Fisher exact and Student t tests were used to evaluate the statistical significance of therapy success rates, clinical characteristics, and scanning parameters between the two groups. RESULTS: Group NS included 135 (81.3%) of 166 patients, with 36 (26.7%) of 135 lost to follow-up. Group S included 31 (18.7%) of 166 patients, with eight (26%) of 31 patients lost to follow-up. There was no significant difference (P =.61) in treatment success rates between group NS (87 of 99, 88%) and group S (21 of 23, 91%). The treatment success rates for thyroid remnants were 87% (48 of 55) for group NS and 91% (10 of 11) for group S (P =.63). Treatment success rates for metastases (mostly lymph nodes) were 89% (39 of 44) for group NS and 83% (10 of 12) for group S (P =.55). CONCLUSION: Thyroid stunning can occur with 185 MBq of 131I in diagnostic imaging. However, data did not show any effect of stunning on the efficacy of 131I therapy for differentiated thyroid carcinoma.

Insular carcinoma of the thyroid with jugular vein invasion.

BACKGROUND: Gross angioinvasion with intraluminal tumor thrombus is rarely seen in thyroid cancer, with few cases reported in the literature. METHODS: We report an insular carcinoma of the thyroid displaying this aggressive local invasion and angioinvasion of the internal jugular chain. Complete surgical removal of the intraluminal disease, regional metastasis, and primary tumor was carried out. RESULTS: Adjuvant external beam radiation therapy and iodine-131 were administered, and the patient died with pulmonary metastases 30 months after surgery. No locoregional recurrence was noted at last follow-up. CONCLUSIONS: Treatment of insular carcinoma of the thyroid with invasion of the internal jugular vein is amenable to surgical resection. Postoperative radioactive iodine and external beam radiotherapy can achieve locoregional disease control and prolonged survival.

Feasibility of a randomized trial on adjuvant radio-iodine therapy in differentiated thyroid cancer.

BACKGROUND: Justification for adjuvant radio-iodine (I-131) therapy in differentiated thyroid cancer (DTC) is purely based on retrospective data. This is true for ablative therapy and even more so for high-dosage adjuvant schedules. Randomized trials on the latter application are considered impossible due to anticipated formidable sample sizes required in a disease with an overall excellent prognosis like DTC. OBJECTIVE: To develop and validate a model that could stratify for risk of recurrence, rather than survival, as is usually done in prognostic indices, and secondly, to use this model to estimate the sample size required for a randomized trial. DESIGN, PATIENTS AND RESULTS: From databases of three large Dutch centres, we identified 342 consecutive patients without known residual DTC after (near-) total thyroidectomy. Using Cox proportional hazards analysis, a model was validated that clearly distinguished risk categories of recurrence using commonly available baseline variables. The model included age, N stage at presentation and T stage in papillary carcinoma. According to this stratification, a subset of patients at substantial risk for relapse (30-40%) was identified. They could be eligible for a trial assessing the impact of high-dose adjuvant I-131 on recurrence rates. Assuming a clinically relevant effect of 30% reduction of relapses, 290 patients would have to be entered in either arm (alpha 0.05, power 80%). CONCLUSION: We conclude that even though a randomized trial on this issue will be difficult to design and conduct, sample size is not the main problem.

The role of radioactive iodine in the treatment of advanced differentiated thyroid carcinoma.

OBJECTIVE: 131I therapy may be beneficial for patients with advanced differentiated thyroid cancer (DTC) but there have been relatively few studies of the prognostic factors which influence the outcome. We have evaluated differences in outcome in relation to histology, localization of tumour, differentiation grade, age and sex after 131I as the only secondary treatment for advanced stages of DTC. DESIGN: Retrospective study of a selected patient group treated according to a fixed protocol. PATIENTS: We studied the outcome in 86 patients with stage pN3, pT4 or pM1 out of total of 432 patients treated for DTC from 1970 until 1991. RESULTS: The overall cure rate of 131I therapy after a mean follow-up of 12.1 years was 50% (papillary 65% vs follicular 23%). The overall 5-year progression free survival (PFSR) was 66%. Three out of 11 patients with bone metastases from follicular cancer were cured after a mean dose of 13.2 GBq, significantly less than the average dose of 28.4 GBq given to all patients with bone metastases. In the univariate analysis of 5-year PFSR histology (papillary 79% vs follicular 43%), differentiation grade (well differentiated 81% and moderately differentiated 31%), tumour stage (pN3100%, pT4 77% and M1 48%), and age (< or = 60 years 85% vs > 60 years 46%) were significant prognostic factors. A multivariate analysis showed differentiation grade, histology and age to be significant prognostic variables for outcome (moderately vs well differentiated: RR = 3.16, follicular vs. papillary: RR = 2.56 and age > 60 vs age < or = 60: RR = 2.43). CONCLUSIONS: 131I can be an effective treatment in patients with advanced differentiated thyroid cancer at all sites and can cure, on average, 50% of all patients with advanced differentiated thyroid cancer.

[Recurrences and metastases in differentiated thyroid cancer]. / Retsidivi i metastazi pri diferentsiran rak na shtitovidna zhleza.

A total of 201 patients presenting differentiated thyroid gland carcinoma (DTGC), all of them in T1-3Ha-bMo stage, are followed up over a 10-year period, 1980 through 1989. Thyroidectomy with ensuing 131I radiotherapy is used in the treatment of 74 cases, and varying in extent resections--in the remainder. Women up to 50, and men up to 40 years of age (totalling 138 cases) are assigned to low-risk age groups (LRG), and those exceeding the aforementioned age limit (63 cases)--to high-risk age groups (HRG). Local recurrences and lymph node metastases are recorded in 17.5 per cent of the patients undergoing thyroidectomy followed by iodine radiotherapy. Among those subjected to radical resections the rate of recurrences of the lesion amounts to 2.4 per cent. In the HRG the rate of recurrences among thyroidectomized patients is 32 per cent, whereas in those assigned to LRG, treated with organ salvaging operations, the recurrences are 10.1 and 1.1 per cent, respectively. It is established that insofar as recurrences of the lesion are concerned the fifth year remains a high-risk period; by the second year they are increased more than three times. Lymph-node metastases are observed in 80 per cent of the cases by the second year. Local recurrences are more common in HRG--83.3 per cent. As shown by the results of the series reviewed, thyroidectomy followed by 131I radiotherapy fails to improve the prognosis in HRG patients. In these cases better results are attained in those subjected to wide resection of the thyroid gland.