Radioactive iodine therapy strategies for distinct types of differentiated thyroid cancer: a propensity score-matched analysis

Background

The management guidelines of radioactive Iodine (RAI) therapy for distinct types of differentiated thyroid carcinoma (DTC) were the same in clinical practice. However, in distinct types DTC, differences in RAI avidity and response existed and the effect of RAI therapy could not be equated.

Methods

DTC patients' data in SEER database were extracted to perform retrospective analysis. The differences between case group and control group were compared by chi-square tests. We used Kaplan-Meier statistics and Cox regression analyses to investigate cancer-specific survival (CSS). Propensity score-matched was performed to make 1:1 case-control matching.

Results

105195 patients who receiving total thyroidectomy were identified in SEER database. Compared to papillary thyroid carcinoma (PTC) (52.3%), follicular thyroid carcinoma (FTC) (63.8%) and oncocytic carcinoma of thyroid (OCA) (64.4%) had higher rates of RAI therapy. In the multivariable Cox regression model, RAI therapy was independent prognosis factor in PTC but not in OCA and FTC. In subgroup analysis, RAI therapy could improve prognosis in PTC when gross extrathyroidal extension or lymph node metastases or early survival when distant metastases (DM) were presented. However, OCA and FTC patients with DM rather than regional lesions only could benefit from RAI therapy. High-risk patients receiving RAI therapy showed a better prognosis in PTC but not in OCA and FTC.

Conclusion

RAI therapy was an effective treatment for DTC and should be considered individually in PTC, OCA and FTC patients. Our results provided further guideline for treatment selection in DTC.

Development and Validation of a Diagnostic Nomogram for the Preoperative Differentiation Between Follicular Thyroid Carcinoma and Follicular Thyroid Adenomas

OBJECTIVE

The aim of the study was to construct and validate a nomogram for differentiating follicular thyroid carcinoma (FTC) from follicular thyroid adenoma (FTA).

METHODS

Two hundred patients with pathologically confirmed thyroid follicular neoplasms were retrospectively analyzed. The patients were randomly divided into a training set (n = 140) and validation set (n = 60). Baseline data including demographics, CT (computed tomography) signs, and radiomic features were analyzed. Predictive models were developed and compared to build a nomogram. The predictive effectiveness of it was evaluated by the area under receiver operating characteristic curve (AUC).

RESULTS

The CT model, radiomic model and combination model showed excellent discrimination (AUCs [95% confidence interval] = 0.847 [0.766-0.928], 0.863 [0.746-0.932], 0.913 [0.850-0.975]). The nomogram based on the combination model showed remarkable discrimination in the training and validation sets. The calibration curves suggested good consistency between actual observation and prediction.

CONCLUSIONS

This study proposed a nomogram that can accurately and intuitively predict the malignancy potential of follicular thyroid neoplasms.

Follicular thyroid cancer and Hürthle cell carcinoma: challenges in diagnosis, treatment, and clinical management

Follicular thyroid cancer is the second most common differentiated thyroid cancer histological type and has been overshadowed by its more common counterpart-papillary thyroid cancer-despite its unique biological behaviour and less favourable outcomes. In this Review, we comprehensively review the literature on follicular thyroid cancer to provide an evidence-based guide to the management of these tumours, to highlight the lack of evidence behind guideline recommendations, and to identify changes and challenges over the past decades in diagnosis, prognosis, and treatment. We highlight that correct identification of cancer in indeterminate cytological samples is challenging and ultrasonographic features can be misleading. Despite certain unique aspects of follicular thyroid cancer presentation and prognosis, no specific recommendations exist for follicular thyroid cancer and Hürthle cell carcinoma in evidence-based guidelines. Efforts should be made to stimulate additional research in this field.

Nonanaplastic follicular cell-derived thyroid carcinoma: mitosis and necrosis in long-term follow-up

Nonanaplastic follicular cell-derived thyroid carcinoma (NAFCTC) includes differentiated- (DTC) and poorly differentiated thyroid carcinoma (PDTC). DTC has an excellent prognosis, while PDTC is situated between DTC and anaplastic carcinomas. Short-term studies suggest that PDTC patients diagnosed only on tumor necrosis and/or mitosis have a prognosis similar to those diagnosed according to the TURIN proposal. The purpose of this study was to evaluate prognosis for NAFCTC based on long-term follow-up illuminating the significance of tumor necrosis and mitosis. A cohort of 225 patients with NAFCTC was followed more than 20 years. Age, sex, distant metastasis, histology, tumor size, extrathyroidal invasion, lymph node metastasis, tumor necrosis and mitosis were examined as possible prognostic factors. Median follow-up time for patients alive was 28 years (range 20-43 years). Age, distant metastasis, extrathyroidal invasion, tumor size, tumor necrosis and mitosis were independent prognostic factors in multivariate analysis for overall survival (OS). In disease specific survival (DSS) age was not significant. Using only necrosis and/or mitosis as criteria for PDTC the 5-, 10- and 20-year OS for DTC was 87, 79 and 69%, respectively. In DSS it was 95, 92 and 90%. For PDTC the 5-, 10- and 20-year OS was 57, 40 and 25%, respectively. In DSS it was 71, 55 and 48%. Tumor necrosis and mitosis are highly significant prognostic indicators in analysis of long time survival of nonanaplastic follicular cell-derived thyroid carcinoma indicating that a simplification of the actually used criteria for poorly differentiated carcinomas may be justified.

What is the Minimal Surgery for Papillary Thyroid Carcinoma?

Although thyroid surgery for treatment of papillary thyroid carcinoma (PTC) has been practiced for more than 100 years, there is still controversy regarding the minimal surgery needed for cure. The main reason for this controversy is lack of prospective randomized trials. The data accumulated in the last four decades indicate that hemithyroidectomy can be sufficient and safely practiced in low-risk patients with PTC. Patients <45 years of age with a single tumor less than 2 cm, with no lymphatic spread, and in the absence of other risk factors, can be equally managed by hemithyroidectomy or total thyroidectomy. A slight increase in the risk of vocal cord paralysis and hypocalcemia after total thyroidectomy suggests that hemithyroidectomy is appropriate for the management of patients with stage T1 disease. Any choice regarding the extent of surgery should be made with the patient and his family and in a multidisciplinary setup, which has been shown to improve decision-making procedures before the operation and during follow-up.

Scoring System for Mortality in Patients Diagnosed with and Treated Surgically for Differentiated Thyroid Carcinoma with a 20-Year Follow-Up

Background

Differentiated thyroid carcinoma (DTC) is associated with an increased mortality. Few studies have constructed predictive models of all-cause mortality with a high discriminating power for patients with this disease that would enable us to determine which patients are more likely to die.

Objective

To construct a predictive model of all-cause mortality at 5, 10, 15 and 20 years for patients diagnosed with and treated surgically for DTC for use as a mobile application.

Design

We undertook a retrospective cohort study using data from 1984 to 2013.

Setting

All patients diagnosed with and treated surgically for DTC at a general university hospital covering a population of around 200,000 inhabitants in Spain.

Participants

The study involved 201 patients diagnosed with and treated surgically for DTC (174, papillary; 27, follicular).

Exposures

Age, gender, town, family history, type of surgery, type of cancer, histological subtype, microcarcinoma, multicentricity, TNM staging system, diagnostic stage, permanent post-operative complications, local and regional tumor persistence, distant metastasis, and radioiodine therapy.

Main outcome measure

All-cause mortality.

Methods

A Cox multivariate regression model was constructed to determine which variables at diagnosis were associated with mortality. Using the model a risk table was constructed based on the sum of all points to estimate the likelihood of death. This was then incorporated into a mobile application.

Results

The mean follow-up was 8.8±6.7 years. All-cause mortality was 12.9% (95% confidence interval [CI]: 8.3–17.6%). Predictive variables: older age, local tumor persistence and distant metastasis. The area under the ROC curve was 0.81 (95% CI: 0.72–0.91, p<0.001).

Conclusion

This study provides a practical clinical tool giving a simple and rapid indication (via a mobile application) of which patients with DTC are at risk of dying in 5, 10, 15 or 20 years. Nonetheless, caution should be exercised until validation studies have corroborated our results.

Clinical significance of integrin β6 as a tumor recurrence factor in follicular thyroid carcinoma

BACKGROUND

Overexpression of integrin β6 plays an important role in a variety of malignant tumor invasion and metastasis.

METHODS

The expression levels of integrin β6, matrix metalloproteinase (MMP)-2 and MMP-9 were analyzed by immunohistochemistry with human follicular thyroid carcinomas. Then we investigated their correlation with clinical outcomes parameters, relationship, and the survival time.

RESULTS

The integrin β6 staining was expressed in cellular membrane and cytoplasm of follicular thyroid carcinoma cells. The MMP-2 and MMP-9 expressions were mainly found in cellular cytoplasm. In correlation with the clinical outcome parameters of 60 patients, there were significant statistical differences of integrin β6, MMP-2, and MMP-9 expression levels in different size of tumor. Integrin β6 and MMP-9 expressions have significant statistical differences in T classifications. MMP-2 and MMP-9 expressions have significant statistical differences in different M classification. Other clinical outcome parameters had no significant statistical differences.

CONCLUSION

Integrin β6 expression correlated significantly with MMP-9 expression, and may be a valuable recurrence indicator for follicular thyroid carcinomas.

Is there survival benefit from life-long follow-up after treatment for differentiated thyroid cancer?

A best evidence topic was written according to a structured protocol. The question addressed was whether there is a survival benefit from life-long follow-up after treatment for thyroid cancer. A total of 137 papers were identified using the reported searches of which 7 represented the best evidence to answer the clinical question. The authors, date, journal, study type, population, main outcome measures and results are tabulated. The existing guidelines for follow-up in thyroid cancer recommend life-long follow-up as recurrence may present after 5 years. However, the strategy of life-long follow-up for everyone (as advised by the British, European and American Thyroid Association guidelines) is not evidence-based. The issue is that some of the recurrences may present after 5 years and low volume recurrence may be more effectively treated. However, as in many other malignancies, there is no study that reliably shows a survival benefit conferred from life-long follow-up, especially in stage 1 disease. Moreover, the risk of recurrence only parallels the risk of disease-specific mortality in the older thyroid cancer patient group (>45 years at diagnosis). The evidence from the present review supports a risk stratified approach to follow-up for thyroid cancer since low-risk thyroid cancer is associated with low recurrence rates and mortality compared to the other groups. For young patients (<45 years at diagnosis) with stage 1 disease, there is no proven survival benefit from life-long follow-up following primary treatment. These patients could be safely discharged to primary care after 5 years for follow-up with yearly thyroglobulin measurements.

Impact of surgical technique on operative morbidity and its socioeconomic benefit in thyroid surgery

PURPOSE

The aim of this retrospective cohort study was to evaluate the rate of complications in relation to the extent of surgery and some of its consequences.

METHODS

Between 1972 and 2010, a total of 5,277 consecutive thyroid gland surgeries with 7,383 nerves at risk were performed at our teaching institution. Data of all patients undergoing thyroidectomy were collected prospectively. A total of 2,867 subtotal resections (first study period from 1972 to 1990) were compared with 2,410 extended thyroid resections involving at least a hemithyroidectomy (second period from 1991 to 2010).

RESULTS

The incidence of permanent recurrent laryngeal nerve palsy in primary operations was significantly higher in the first period compared to the second period (3.6 vs. 0.9 %; p < 0.001). Permanent hypoparathyroidism decreased from 3.2 % in the first period to 0.8 % in the second period (p < 0.001). The incidence of recurrent goiter surgery decreased from 11.1 % in the first period to 8.1 % in the second period (p < 0.001). No significant difference was found in permanent recurrent laryngeal nerve palsy in recurrent disease between the two periods. The socioeconomic benefits of an extended thyroid resection in our patient population are 360 preventable operations, 90 preventable permanent recurrent laryngeal nerve palsies, and 58 preventable cancers. Furthermore, 37 preventable radioiodine ablations and 15 preventable deaths were associated with more radical thyroid resection.

CONCLUSION

Improvements in surgical technique and change in surgical strategy significantly decreased the prevalence of recurrent laryngeal nerve palsy, hypoparathyroidism, and recurrent disease as well as reduced public health costs associated with recurrent goiter.

Prognostic factors and follow-up of patients with differentiated thyroid carcinoma with false negative or nondiagnostic FNAC before surgery. Comparison with a control group

Since the clinical implementation of fine needle aspiration cytology (FNAC) to diagnose thyroid carcinoma, few patients remain misdiagnosed and little is known about their clinical outcomes. An observational retrospective study was carried out to analyse prognostic factors and follow-up of patients with differentiated thyroid carcinoma (DTC) not disclosed by FNAC before surgery, compared to a control group. From October 2003 to July 2010, 308 patients underwent surgery as treatment for nodular goitre and 53 had DTC. Cases were 12 subjects with DTC and benign (n = 7) or nondiagnostic (n = 5) FNAC. Controls were 39 subjects with DTC and suspicious (n = 19) or malignant (n = 20) FNAC. Prognostic factors, recurrence and survival rates were compared. Cases had longer time from FNAC to surgery than the control group (86.8 ± 74.1 vs. 16.4 ± 23.8 weeks; P < 0.001), higher prevalence of follicular carcinoma (33.3 vs. 2.6%; P = 0.009), and of two-time total thyroidectomy (75 vs. 30.8%; P = 0.016). Average follow-up was 42.7 ± 25.3 months (2-86 months). There were no deaths. Disease-free survival for cases was 66.9 ± 5.8 months, and for controls 78.7 ± 3.9 months (P: ns). In patients with DTC, the result of the FNAC performed before surgery was not an independent predictor of recurrences or mortality in the first 7 years of follow-up. Thus, false negative or nondiagnostic FNAC in a patient with DTC does not seem to be a primary prognostic factor, but it may reveal other adverse prognostic factors such as longer time to therapy and higher prevalence of follicular carcinoma that may influence long-term outcomes.

Defining cure for esophageal cancer: analysis of actual 5-year survivors following esophagectomy

BACKGROUND

Esophagectomy is the mainstay of curative treatment for localized esophageal cancer. However, what constitutes cure is not well defined. This study was undertaken to characterize actual 5-year survivors following esophagectomy and to determine prognostic factors for disease-specific survival (DSS) from 60 months.

MATERIALS AND METHODS

Between 1987 and 2004, 398 consecutive patients underwent esophagectomy and had potential for 5 years follow-up. Clinicopathological factors associated with DSS from 5 years onward were analyzed.

RESULTS

Median DSS was 25 months. Neoadjuvant therapy was administered to 159 of 398 (40%). There were 114 of 398 (29%) actual 5-year survivors. On multivariate analysis, 5-year survivors were significantly more likely to have lower T classification, N classification, and R0 resections compared with patients who died less than 5 years after surgery. There were 66 of 398 patients (17%) with positive margins, and 6 of these were 5-year survivors. Of the 114 5-year survivors, 17 (15%) subsequently died of esophageal cancer. Prognostic factors for DSS after surviving 5 years were age and T classification for patients treated with neoadjuvant therapy and surgery alone, respectively. Powerful prognostic factors from time of treatment, including nodal status, were no longer prognostic factors after surviving to 5 years.

CONCLUSIONS

No single clinicopathological variable negated survival to 5 years. Prognostication once surviving 5 years is difficult. The majority of 5-year survivors can be considered cured of esophageal cancer.