Failure of radioactive iodine in the treatment of hyperthyroidism.

BACKGROUND: Persistent or recurrent hyperthyroidism after treatment with radioactive iodine (RAI) is common and many patients require either additional doses or surgery before they are cured. The purpose of this study was to identify patterns and predictors of failure of RAI in patients with hyperthyroidism. METHODS: We conducted a retrospective review of patients treated with RAI from 2007 to 2010. Failure of RAI was defined as receipt of additional dose(s) and/or total thyroidectomy. Using a Cox proportional hazards model, we conducted univariate analysis to identify factors associated with failure of RAI. A final multivariate model was then constructed with significant (p < 0.05) variables from the univariate analysis. RESULTS: Of the 325 patients analyzed, 74 patients (22.8 %) failed initial RAI treatment, 53 (71.6 %) received additional RAI, 13 (17.6 %) received additional RAI followed by surgery, and the remaining 8 (10.8 %) were cured after thyroidectomy. The percentage of patients who failed decreased in a stepwise fashion as RAI dose increased. Similarly, the incidence of failure increased as the presenting T3 level increased. Sensitivity analysis revealed that RAI doses <12.5 mCi were associated with failure while initial T3 and free T4 levels of at least 4.5 pg/mL and 2.3 ng/dL, respectively, were associated with failure. In the final multivariate analysis, higher T4 (hazard ratio [HR] 1.13; 95 % confidence interval [CI] 1.02-1.26; p = 0.02) and methimazole treatment (HR 2.55; 95 % CI 1.22-5.33; p = 0.01) were associated with failure. CONCLUSIONS: Laboratory values at presentation can predict which patients with hyperthyroidism are at risk for failing RAI treatment. Higher doses of RAI or surgical referral may prevent the need for repeat RAI in selected patients.

The role of intraoperative frozen section if suspicious for papillary thyroid cancer.

BACKGROUND: Optimal surgical intervention is straightforward when a fine-needle aspiration (FNA) is diagnostic for papillary thyroid cancer (PTC). However, if there are characteristics of an aspirate suspicious for PTC but not meeting criteria for diagnosis of PTC, the management is less clear. METHODS: Of the 1,051 patients who underwent thyroid surgery at the University of Wisconsin between May 24, 1994, and October 21, 2004, 102 had preoperative FNA cytology that was diagnostic or suspicious for PTC. Within the subgroups of diagnostic for PTC and suspicious for PTC, we evaluated the accuracy of FNA, the utility of frozen section (FS), and the predictive value of demographic and pathologic variables. RESULTS: When diagnostic for PTC, FNA was 97% accurate and FS did not alter management. However, if an FNA was interpreted as suspicious for PTC, there was a 57% (17/30) likelihood of PTC on permanent histology. In this subgroup, FS led to the optimal operative procedure in 96% (25/26) of cases. With the exception of size greater than 4 cm, demographic and pathologic variables did not predict malignancy or increase the likelihood of an FNA being diagnostic for PTC. CONCLUSION: Intraoperative FS is a useful diagnostic tool when an FNA is suspicious for PTC.

Higher serum thyroid stimulating hormone level in thyroid nodule patients is associated with greater risks of differentiated thyroid cancer and advanced tumor stage.

CONTEXT: TSH is a known thyroid growth factor, but the pathogenic role of TSH in thyroid oncogenesis is unclear. OBJECTIVE: The aim was to examine the relationship between preoperative TSH and differentiated thyroid cancer (DTC). DESIGN: The design was a retrospective cohort. SETTING, PARTICIPANTS: Between May 1994 and January 2007, 1198 patients underwent thyroid surgery at a single hospital. Data from the 843 patients with preoperative serum TSH concentration were recorded. MAIN OUTCOME MEASURES: Serum TSH concentration was measured with a sensitive assay. Diagnoses of DTC vs. benign thyroid disease were based on surgical pathology reports. RESULTS: Twenty-nine percent of patients (241 of 843) had DTC on final pathology. On both univariate and multivariable analyses, risk of malignancy correlated with higher TSH level (P=0.007). The likelihood of malignancy was 16% (nine of 55) when TSH was less than 0.06 mIU/liter vs. 52% (15 of 29) when 5.00 mIU/liter or greater (P=0.001). When TSH was between 0.40 and 1.39 mIU/liter, the likelihood of malignancy was 25% (85 of 347) vs. 35% (109 of 308) when TSH was between 1.40 and 4.99 mIU/liter (P=0.002). The mean TSH was 4.9+/-1.5 mIU/liter in patients with stage III/IV disease vs. 2.1+/-0.2 mIU/liter in patients with stage I/II disease (P=0.002). CONCLUSIONS: The likelihood of thyroid cancer increases with higher serum TSH concentration. Even within normal TSH ranges, a TSH level above the population mean is associated with significantly greater likelihood of thyroid cancer than a TSH below the mean. Shown for the first time, higher TSH level is associated with advanced stage DTC.

Initial lymph node dissection increases cure rates in patients with medullary thyroid cancer.

OBJECTIVE: Medullary thyroid carcinoma (MTC) is the third most common type of thyroid cancer. MTC spreads early to local lymph nodes, and most endocrine surgeons recommend total thyroidectomy with central lymph node dissection (CLND) as the minimum initial operation. We reviewed our experience to determine if the initial operation influences clinical outcomes. METHODS: Twenty-two patients with sporadic or inherited MTC who received surgery at one academic centre between 1994 and 2004 were identified. Clinical, operative, and pathology findings were reviewed. RESULTS: Ten patients had prophylactic thyroidectomy for hereditary MTC, while 12 patients underwent therapeutic operations for sporadic MTC. The average age of the prophylactic group was 11 +/- 3, and 43 +/- 6 years for the therapeutic group. All patients in the prophylactic group received thyroidectomy without neck dissection. No patient in the prophylactic group had residual disease or required re-operation. In the therapeutic surgery group, three patients were treated with thyroidectomy plus CLND, and nine patients received thyroidectomy alone. The CLND group had a significantly higher cure rate as demonstrated by a lower incidence of residual disease (0% vs. 89%, p = 0.018), and re-operations (0% vs. 78%, p = 0.045). CONCLUSION: Initial CLND for MTC increases cure rates by reducing residual disease and re-operations.

Is tumor size the best predictor of outcome for papillary thyroid cancer?

BACKGROUND: There are many risk classification schemes that determine both treatment and outcome for patients with papillary thyroid cancer. Most of these formulas often utilize tumor size as the key predictor of outcome. Furthermore, there is no clear consensus regarding the treatment of small papillary cancers. Therefore, we reviewed our experience in order to determine which factors best predict outcome for papillary thyroid cancer. In addition, we sought to establish a tumor size threshold beyond which papillary cancers require treatment. METHODS: From May 1994 to October 2004, 174 patients underwent surgery for papillary thyroid cancer (PTC) at our institution. These patients were divided into five groups based on tumor size. The data from these groups were analyzed utilizing ANOVA, Chi-square and linear regression analysis. RESULTS: The mean age of the patients was 42 +/- 1 years and 126 (72%) were female. Mean tumor size was 17.2 +/- 1.1 mm. The overall outcome was quite good with a survival rate of 97% and a recurrence rate of 12%. On univariate analysis, there was no difference amongst the groups in regards to age or gender. However, there was a significantly higher incidence of lymph node metastasis amongst those with the largest tumors. Consequently, those patients with the largest tumors were treated more aggressively, with 75% undergoing total thyroidectomies and 85% receiving radioactive iodine therapy. However, on univariate and multivariate analysis, tumor size was not shown to correlate with higher recurrence. Rather, the only factor associated with a greater recurrence rate was the presence of lymph node metastases. CONCLUSION: At our institution, the recurrence rates for PTC were similar for all sizes of tumors. Furthermore, presence of metastatic disease at the time of diagnosis, rather than tumor size, seems to be a better predictor of recurrence and outcome.

What is the biology and optimal treatment for papillary microcarcinoma of the thyroid?

BACKGROUND: Papillary microcarcinomas of the thyroid, defined as tumors measuring < or =10 mm, are believed to be a less aggressive subset of papillary cancers that behave more like benign lesions and are often more conservatively treated. However, some groups have reported a high incidence of metastases from papillary microcarcinomas and favor aggressive surgical resection followed by radioiodine therapy. Therefore, to characterize the biology and optimal treatment for papillary microcarcinomas, we reviewed our experience. METHODS: From May 1994 to October 2004, 184 patients underwent thyroid surgery at the University of Wisconsin and had papillary thyroid cancer present in the resected gland. Of these patients, 10 were excluded because there was no record of tumor size. Of the remaining 174 patients, 74 (42%) had papillary microcarcinomas. Data from these patients were retrospectively analyzed. RESULTS: The mean age of these patients was 42 +/- 1.48 year and 57 (77%) were female. The mean tumor size was 5.7 +/- 0.38 mm. Of the 74 patients, 12 (16%) had lymph node metastases. The majority of patients (65%) underwent a total thyroidectomy and 61% had radioiodine ablation therapy after surgery. With follow-up up to 134 months, the recurrence rate was 8% and only two patients currently have active disease. No patients with papillary microcarcinoma have died during this period. CONCLUSION: Papillary microcarcinomas of the thyroid are quite common, comprising almost half of all papillary cancers. Despite a significant rate of metastatic disease, the prognosis for patients with microcarcinomas has been excellent with 100% survival and a low recurrence rate. These outcomes may be the result of the aggressive surgical therapy used at our institution. Thus, papillary microcarcinomas appear to have a similar biology to other low risk papillary thyroid cancers and, in our opinion, may warrant similar treatment.

El pacto internacional de derechos económicos, sociales y culturales y el empoderamiento de las mujeres / The international covenant on economic, social and cultural rights and the empowerment of women

Busca promover la igualdad de oportunidades para las mujeres en el ámbito del empleo, dada la desigualdad y la inequidad persistentes. Se tratará de incorporar los DES en las políticas públicas, leyes y procedimientos administrativos de los cinco países andin