Clinicopathological features and outcomes after radioactive iodine treatment of oncocytic well-differentiated thyroid carcinomas.

OBJECTIVE: The aim of this study was to compare the clinicopathological features of Hürthle cell carcinomas (HCC) and oncocytic papillary thyroid carcinomas (OPTC) and to evaluate their response to radioactive iodine (RAI) treatment. METHODS: We retrospectively reviewed the charts of patients with histopathologically verified OPTC (group 1) and HCC (group 2), during a 17-year period. All patients underwent total thyroidectomy and received RAI adjuvant therapy. Clinicopathological characteristics of the two groups were compared. Response to initial therapy was assessed 6 to 24 months after RAI ablation according to the American Thyroid Association dynamic risk reclassification. Clinical outcomes were evaluated. RESULTS: A total of 28 patients (8 OPTC and 20 HCC) were included. There was no significant difference in clinicopathological features including sex, age, tumour size and vascular invasion. Distant metastases were absent in both groups. OPTC, however, presented more features of local invasion (50% vs. 10%, P = 0.03), extrathyroidal extension (25% vs. 0%, P = 0.07) and lymph node involvement (37.5% vs. 0%, P = 0.01). Median cumulative RAI activity administered to both groups was 200 mCi (range: 100-300 mCi). Response to RAI therapy was excellent in all HCC and 87.5% of OPTC (P = 0.28). One patient with OPTC (12.5%) presented an indeterminate response. Clinical outcomes were favourable after a median follow-up of 87.5 and 49 months, respectively. CONCLUSION: Although OPTC presented more locoregional invasion, clinicopathological characteristics of OPTC and HCC were comparable. Both OPTC and HCC were iodine responsive. We suggest that adjuvant RAI therapy after total thyroidectomy is beneficial for OPTC and HCC and may improve disease-free survival.

Comparison of clinical characteristics of patients with follicular thyroid carcinoma and Hürthle cell carcinoma. / Comparación de las características clínicas en pacientes con carcinoma folicular de tiroides y carcinoma de células de Hürthle.

INTRODUCTION: Hürthle cell carcinoma (HCC) is an uncommon thyroid cancer historically considered to be a variant of follicular thyroid carcinoma (FTC). The aim of this study was to assess the differences between these groups in terms of clinical factors and prognoses. PATIENTS AND METHODS: A total of 230 patients (153 with FTC and 77 with HCC) with a median follow-up of 13.4 years were studied. The different characteristics were compared using SPSS version 20 statistical software. RESULTS: Patients with HCC were older (57.3±13.8 years vs. 44.6±15.2 years; P<.001). More advanced TNM stages were also seen in patients with HCC and a greater trend to distant metastases were also seen in patients with HCC (7.8% vs. 2.7%, P=.078). The persistence/recurrence rate at the end of follow-up was higher in patients with HCC (13% vs. 3.9%, P=.011). However, in a multivariate analysis, only age (hazard ratio [HR] 1.10, confidence interval [CI] 1.04-1.17; P=.001), size (HR 1.43, CI 1.05-1.94; P=.021), and histological subtype (HR 9.79, CI 2.35-40.81; P=.002), but not presence of HCC, were significantly associated to prognosis. CONCLUSION: HCC is diagnosed in older patients and in more advanced stages as compared to FTC. However, when age, size, and histological subtype are similar, disease-free survival is also similar in both groups.

Favorable Outcome of Hurthle Cell Carcinoma of the Thyroid Treated With Total Thyroidectomy, Radioiodine, and Selective Use of External-Beam Radiotherapy.

OBJECTIVES: There is controversy about the prognosis of Hurthle cell carcinoma of the thyroid. The purpose of this project is to report the outcome of a well-defined group of patients treated at a single institution in the modern era. METHODS: Sixteen patients met the following inclusion criteria: Treatment with curative intent at our institution between January 1, 1997, and December 31, 2010. Primary treatment with total thyroidectomy with or without neck dissection. Age >18 years at the time of thyroidectomy. Confirmation by a pathologist of the diagnosis of a primary Hurthle cell carcinoma of the thyroid based on ≥75% Hurthle cells with extension through the tumor capsule. No areas of poorly differentiated (insular) or undifferentiated (anaplastic) carcinoma. Stage T1-3, NX-1b, M0. All patients received radioiodine immediately after thyroidectomy (remnant ablation, n=14) or as adjuvant for a recurrence (n=2). External-beam radiotherapy to the neck as adjuvant therapy after thyroidectomy was used in 2 patients and after resection of a neck recurrence in 1 patient. RESULTS: Five-year actuarial rates with a median 6 years of follow up on surviving patients were as follows:Overall and cancer-specific survival: 92% (1 death from Hurthle cell carcinoma). Relapse-free survival (no visible tumor and unstimulated thyroglobulin ≤1.0): 65%. CONCLUSIONS: Our experience suggests that the outcome of Hurthle cell carcinoma of the thyroid is favorable in adults with stage T1-3 NX-1b M0 disease who are managed with total thyroidectomy, radioiodine, and-in selected cases-external-beam radiotherapy. We do not have the ability to compare our results to other management strategies.

Radioactive Iodine Treatment Is Associated with Improved Survival for Patients with Hürthle Cell Carcinoma.

BACKGROUND: Hürthle cell carcinoma (HCC) is not typically iodine avid, raising questions regarding postoperative use of radioactive iodine (RAI). The aims of this study were to describe current practice patterns regarding the use of RAI for HCC and to assess its association with survival. METHODS: The National Cancer Data Base 1998-2006 was queried for all patients with HCC who underwent total thyroidectomy. Inclusion was limited to T1 tumors with N1/M1 disease, and T2-4 tumors with any N/M disease. Patients were divided into two treatment groups based on receipt of RAI. Baseline patient characteristics were compared between the two groups. Survival was examined using Kaplan-Meier and Cox regression analyses. RESULTS: A total of 1909 patients were included. Of these, 1162 (60.9%) received RAI, and 747 (39.1%) did not. Patients treated with RAI were younger (57 vs. 61 years for no RAI, p < 0.001), more often had private insurance (61.7% vs. 53.5% for no RAI, p < 0.003), and were more likely to be treated at an academic center (40.0% vs. 33.1% for no RAI, p < 0.001). Five- and 10-year survival rates were improved for patients who received RAI compared with those who did not (88.9 vs. 83.1% and 74.4 vs. 65.0%, respectively, p < 0.001). RAI administration was associated with a 30% reduction in mortality (hazard ratio = 0.703, p = 0.001). CONCLUSION: Present guidelines are inconsistent with regard to indications for using RAI for HCC. This could explain why nearly 40% of HCC patients did not receive RAI. RAI is associated with improved survival, suggesting that it should be advocated for HCC patients with tumors >2 cm and those with nodal and distant metastatic disease.

Parathyroid carcinoma and oxyphil parathyroid adenoma: an uncommon case of misinterpretation in clinical practice.

A 46 year-old male presented with persistently high level of serum parathyroid hormone (PTH), despite successful resection of an oxyphilic cell parathyroid adenoma of the left lower gland. Renal function and serum calcium were normal, leading to vitamin D deficiency being considered. Tc99m-sestamibi parathyroid scintigraphy showed no capitation, but a cervical ultrasound demonstrated an increase in the lower parathyroids. Surgery confirmed that the right gland was normal but the left corresponded to parathyroid carcinoma. The patient developed severe hypocalcemia, with PTH values being consistent with hypoparathyroidism for a few months. However, a progressive increase in calcium and PTH serum levels indicated recurrence of disease. Tc99m-sestamibi scintigraphy demonstrated hyperfixation in topography of the left inferior parathyroid and the patient was subjected to a third and more extensive surgery, with removal of lymph nodes and adjacent thyroid tissue. Serum calcium and PTH remained elevated, requiring loop diuretics and intravenous bisphosphonates to control hypercalcemia. Cervical radiotherapy was implemented as adjuvant therapy. After two months the patient complained of dyspnea, and a CT scan of the chest demonstrated areas of parenchymal condensation, suggestive of actinic pneumonitis. At the 2-year follow-up no major issues were evident.

Salivary gland toxicity after radioiodine therapy for thyroid cancer.

AIMS: Salivary gland toxicity is a common, but not widely appreciated, adverse effect of high-dose radioiodine (131I). This study was carried out to determine the incidence of symptoms of salivary gland damage after 131I treatment for differentiated thyroid cancer. MATERIALS AND METHODS: This was a prospective study of 76 consecutive patients attending thyroid cancer treatment. Symptoms of salivary gland damage (dry mouth, pain and swelling) were assessed during hospital admission and at follow-up visits. Additionally, a retrospective analysis was carried out of patients recorded in our database as having chronic salivary gland swelling after 131I ablation. RESULTS: Twenty patients (26%) developed salivary gland toxicity, 11 (15%) had symptoms within the first 48 h, continuing for 12 months in seven of these patients. The onset of toxicity in a further nine (12%) patients with persistent symptoms did not occur until 3 months after therapy. In total, 16 (21%) patients had evidence of chronic toxicity, typically xerostomia, at 12 months. Toxicity was more common after repeated 131I administration. After searching our thyroid cancer database, we identified an additional five patients to have chronic salivary gland swelling (chronic sialadenitis or pleomorphic adenoma) 20 months to 23 years after 131I. CONCLUSIONS: Pain, swelling and dry mouth occurred frequently after 131I, with some developing symptoms months or years after administration. Early recognition of salivary gland complications may help to reduce morbidity in these patients.

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.

Large remnant 131I ablation as an alternative to completion/total thyroidectomy in the treatment of well-differentiated thyroid cancer.

BACKGROUND: An alternative to completion thyroidectomy for well-differentiated thyroid carcinoma is to ablate the remnant lobe with 131 I. The purpose of this study is to review our own experience with large remnant ablation. METHODS: A retrospective review of 169 patients with well-differentiated thyroid cancer treated at one institution over a 14-year period was undertaken. Seventy-one patients who underwent partial thyroidectomy (PT) followed by 131 I ablation were identified. This group was compared to 98 patients treated with total thyroidectomy (TT). RESULTS: Mean follow-up was 6.2 years for the 71 PT + 131 I versus 4.7 years for the 98 TT patients (P = .184). Recurrence occurred in 4 of 71 PT + I 131 patients (5.6%) versus 9 of 98 TT patients (9.2%) (P = .393). Other than a tendency for the size of the primary to be slightly larger and for the histology to be follicular carcinoma in the PT + 131 I patients, the 2 groups were nearly identical in age, gender, and other prognostic factors such as capsular invasion and metastases. CONCLUSIONS: Large-dose ablation with 131 I is a viable alternative to completion thyroidectomy. Recurrence rates over an average 6-year period are similar to TT. Long-term monitoring of these cohorts is required.

[Follow-up of children and young adults with differentiated thyroid cancer treated with radioiodine]. / Seguimiento de niños y jóvenes adultos con cáncer diferenciado de tiroides (CDT) tratados con radioyodo.

This is a retrospective study carried out in a group of 30 patients with differentiated thyroid cancer (age at diagnosis equal to or less than twenty years old). The aim of the study is to evaluate outcome after 131I therapy. Patients were classified into three groups on the basis of initial surgery, pathology and scintigraphic results: group I (thyroid extent), group II (locoregional extent), and group III (distant metastatic disease). Clinical parameters, 131I scans, serum thyroglobulin determinations and 131I therapeutic administered doses were evaluated in the follow-up. Some other complementary techniques such as chest X-ray and pulmonary function tests are also described. Scintigraphic absence of thyroid tissue has been observed in 83% of the cases; high thyroglobulin level is still detectable in 34% of the patients as a single evidence of disease, and 21% remain without any abnormal clinical, scintigraphic or analytical findings. Total doses administered have increased in groups I, II and III respectively, and have also been inversely proportional to the extension of lymph node surgery. At present, all the patients are alive and in good general condition. According to the results obtained, we conclude that children and young adults with DTC should undergo periodical 131I therapeutic doses in case of positive scans (once total thyroidectomy has been realized, with or without lymph node resection depending on the extension of disease). In our experience, the use of radioiodine is effective and safe in the follow-up of children and youngs with DTC.

Lack of impact of radioiodine therapy in tg-positive, diagnostic whole-body scan-negative patients with follicular cell-derived thyroid cancer.

Several reports have suggested a benefit from radioactive iodine (RAI) therapy in Tg-positive, whole-body scan-negative patients with follicular cell-derived thyroid cancer, who were said to have high rates of visualization of uptake in metastases after therapeutic doses of RAI. We sought to evaluate the rate of visualization of RAI uptake in these patients and determine the effect of such therapy on tumor progression and Tg levels. We studied 24 consecutive patients who had been treated with high-dose RAI, four of whom had no evidence of metastasis or persistent cancer. Our results showed that four patients had some uptake in posttherapy scans: in the neck, lung, and mediastinal metastases in one patient, in the thyroid remnant in two, and in a possible neck microrecurrence in one. In 13 patients with macrometastases-tumors 1 cm or greater-tumors progressed and serum Tg increased; five have died of thyroid cancer. The disease remained stable in the seven patients with micrometastases. We concluded that in high-risk patients with follicular cell-derived thyroid cancer with high Tg levels and negative diagnostic whole-body scans, only a small number showed meaningful uptake after high doses of RAI. Therefore, widespread use of empiric RAI therapy for such patients who have a large tumor burden should not be encouraged.

Hürthle cell carcinoma.

Patients with Hürthle cell carcinoma (HCC) of the thyroid often have aggressive tumors and generally have a worse prognosis than those with papillary or follicular thyroid carcinomas. A total thyroidectomy with ipsilateral central neck lymphadenectomy and a modified radical neck dissection, if central or lateral nodes are positive, are indicated for HCC. The completeness of this procedure should be assessed by radioiodine scan 3 to 4 months after surgery. Any thyroid remnant should be ablated with radiolabeled iodine 131 to eliminate all tissue at risk and to facilitate the use of serum thyroglobulin in surveillance for tumor recurrence. Fewer than 10% of these cancers take up radioiodine. Recurrent disease is treated surgically with good palliation and appreciable prolongation of life. Local excision and neck dissection for recurrent neck disease or pulmonary wedge resection for lung metastasis has been shown to be effective. All patients with HCC should be given thyroid hormone because most of these tumors have thyrotropin receptors. External beam radiation may be considered for patients with unresectable disease, but this is considered palliative.