Long-term prognosis of differentiated thyroid cancer with lung metastasis in Korea and its prognostic factors

Effects of Coexistent BRAFV600E and TERT Promoter Mutations on Poor Clinical Outcomes in Papillary Thyroid Cancer: A Meta-Analysis

BACKGROUND

The presence of a telomerase reverse transcriptase (TERT) promoter mutation has been suggested as a potential prognostic marker for thyroid cancer, and a synergistic association with the BRAF^V600E mutation has been demonstrated. The aim of this study was to verify the role of this genetic duet in papillary thyroid cancer (PTC).

METHODS

Studies of the association of BRAF^V600E and TERT promoter mutations with clinicopathologic features, recurrence, or PTC-related mortality were included from PubMed and Embase databases (inception to September 2016).

RESULTS

Thirteen eligible studies incorporating 4347 patients with PTC were included, and 283 (median 8.3%) of these patients had coexistent BRAF^V600E and TERT promoter mutations. The coexistence of the two mutations was far more strongly associated with high-risk clinicopathologic features than either mutation alone was, including advanced TNM stage (vs. BRAF^V600E: odds ratio [OR] = 4.19 [confidence interval (CI) 3.07-5.71]; vs. TERT: OR = 4.66 [CI 2.67-8.13]), extrathyroidal extension (vs. BRAF^V600E: OR = 3.1 [CI 2.2-4.37]; vs. TERT: OR = 5.66 [CI 3.02-10.6]), lymph node metastasis (vs. BRAF^V600E: OR = 1.59 [CI 1.16-2.17]; vs. TERT: OR = 2.03 [CI 1.22-3.38]), and distant metastasis (vs. BRAF^V600E: OR = 11.76 [CI 5.63-24.58]). The coexistence of the mutations showed the highest risk of recurrence (coexistence vs. no mutations: hazard ratio [HR] = 6.60 [CI 3.82-11.40]; BRAF^V600E vs. no mutations: HR = 1.31 [CI 0.49-3.46]; TERT vs. no mutations: HR = 3.38 [CI 0.85-13.35]). Moreover, PTC-related mortality was significantly higher with coexistent mutations than in the presence of BRAF^V600E alone (HR = 20.07 [CI 8.37-48.09]).

CONCLUSIONS

Coexistent BRAF^V600E and TERT promoter mutations have a synergistic effect on clinical outcomes in PTC, whereas each mutation alone has a modest effect. Therefore, molecular testing of BRAF^V600E and TERT promoter mutations together is useful in assessing risk stratification of PTC.

Analysis of radioiodine therapy and prognostic factors of differentiated thyroid cancer patients with pulmonary metastasis: An 8-year retrospective study

To assess the efficacy of radioiodine therapy (RIT) and investigate the prognostic factors for patients with pulmonary metastasis secondary to differentiated thyroid carcinoma (DTC) through a retrospective study. A total of 80 patients with radioactive iodine-131 (I)-avid pulmonary metastasis from DTC treated with I from 2007 to 2014 at our institution entered the study. Treatment response was mainly measured by two parameters: serum thyroglobulin (Tg) levels and post-therapeutic I whole-body scan (WBS). Treatment variables were assessed for statistical significance using the univariate and multivariate analyses. A receiver-operating characteristic (ROC) curve was also plotted to verify the accuracy of predictors. Of these 80 patients, the overall effective rate was 72.5% (58/80), the rates for complete response (CR), partial response (PR), and no response (NR) were 20.0%, 52.5%, and 27.5%, respectively. Univariate analysis showed that gender, pulmonary nodule size, absence or presence of extrapulmonary distant metastases, age, and Tg level at diagnosis were significantly associated with I therapy efficacy. Binary logistic regression analysis revealed that older patients (odds ratio [OR]:1.481, 95% confidence interval [CI]: 1.457-2.091, P = .020), subjects with higher Tg levels at diagnosis (OR: 1.046, 95% CI: 1.016-1.119, P = .014), and those with extrapulmonary distant metastases (OR: 1.185, 95%CI: 1.025-1.463, P = .020) had a higher probability of poor prognosis. The optimal cutoffs for age and Tg level to predict I therapy efficacy for DTC with lung metastases were 46 years old and 55.50 ng/mL, respectively, based on ROC analysis. This study indicated that most DTC patients with pulmonary metastases can obtain partial or complete remission after RIT, while older patients with higher Tg levels at diagnosis and extrapulmonary distant metastases more likely show poor prognosis.

Long-term follow-up of papillary and follicular thyroid carcinomas with bone metastasis

The aims of this study were to investigate papillary and follicular thyroid carcinomas with bone metastasis in various clinical presentations and to determine the prognostic factors after multimodality treatment. A retrospective analysis was performed of 3,120 patients with papillary and follicular thyroid carcinoma. Of these patients, 131 (including 97 women, 71.8%) were diagnosed with bone metastasis and underwent follow-up at the Chang Gung Medical Center. Patients with bone metastasis were categorized into two groups. Group A was comprised of patients who were diagnosed with bone metastasis either before thyroidectomy or within 6 months of the initial thyroidectomy (90 patients, 68.7%). Group B was comprised of patients with bone metastasis who received a diagnosis 6 months post-thyroidectomy in the follow-up period (41 patients, 31.3%). After a mean follow-up period of 8.4 ± 7.0 years, there were 88 deaths (67.2%) attributed to thyroid cancer and 13 patients (9.9%) achieved disease-free status. A multivariate analysis showed that older age, early diagnosis, and brain metastasis were each associated with a poor prognosis. The difference in disease-specific mortality rates between groups A and B was significant (p < 0.0001). In conclusion, papillary and follicular thyroid cancers with bone metastasis have a high rate of mortality. Despite this high mortality, 9.9% patients still had an excellent response to treatment.

Prognostic indicators for papillary thyroid carcinoma

Differentiated thyroid cancer (DTC) includes more than 90% of all thyroid carcinoma and its incidence is growing, mainly due to an increase in the incidence of papillary thyroid cancer (PTC) for the widespread use of neck ultrasonography. Areas covered: Several prognostic factors should be considered during the management of PTC in order to provide the most effective treatment. The most important prognostic factors in PTC include personal and pathological features such as patient's age, gender, hystotype, tumor size, extrathyroidal extension, lymph node involvement, presence of local or distant metastases and molecular analyses. We performed a search in the PubMed database for studies published in English since 1960 using the terms: 'thyroid cancer', 'prognostic factors', 'age', 'gender', 'hystotype', 'tumor size', 'extrathyroidal extension', 'lymph node', 'metastases' and 'molecular analyses'. Expert commentary: Prognostic factors can guide clinicians during the treatment and follow-up of DTC patients, but it is now evident that the risk of recurrence or death must be evaluated periodically, on the basis of individual risk, according to the response to initial therapy or the subsequent therapy required during follow-up.

Initial Size of Metastatic Lesions Is Best Prognostic Factor in Patients with Metastatic Differentiated Thyroid Carcinoma Confined to the Lung

BACKGROUND

For patients with lung metastases of differentiated thyroid carcinoma (DTC), there is no consensus on the maximal size of metastatic lesions to use when determining the intensity of follow-up and additional therapeutic options. This study evaluated the clinical outcomes and survival of patients with metastatic DTC confined to the lung, using the maximal diameter of lung lesions in the initial computed tomography.

METHODS

This retrospective cohort study included 112 DTC patients with metastases confined to the lung. The clinical responses were evaluated according to changes in the serum levels of stimulated thyroglobulin or antithyroglobulin antibody, disease status was evaluated according to radiological findings, progression-free survival (PFS), and cancer-specific survival (CSS).

RESULTS

Macronodular lung metastases (≥1 cm) were observed in 27 (24%) patients, and these patients had significantly poor biochemical responses and disease status (p < 0.001, and p < 0.001, respectively), irrespective of radioactive iodine (RAI) avidity. After adjusting for age, sex, primary tumor size, extrathyroidal invasion, cervical lymph node metastasis, time of lung metastasis, and RAI avidity, the macronodular group also had shorter PFS and CSS (p = 0.009 and p = 0.03, respectively) than the micronodular group. From the multivariate analyses, RAI avidity was not an independent prognostic factor predicting PFS and CSS. In the subgroup analyses, RAI avidity was a significant prognostic factor associated with better PFS and CSS (p = 0.013 and p = 0.021, respectively) in the micronodular group only.

CONCLUSIONS

The initial largest diameter of metastatic lesions is the most important prognostic factor for predicting poor clinical outcomes and survival in patients with metastatic DTC confined to the lung.

DEATH RELATED TO PULMONARY METASTASIS IN PATIENTS WITH DIFFERENTIATED THYROID CANCER

OBJECTIVE

The purpose of the present study was to investigate the predictive factors for shorter disease-specific survival in patients with pulmonary disease secondary to differentiated thyroid cancer (DTC).

METHODS

This was a retrospective cohort study conducted over a 5-year period that included 54 patients with pulmonary disease secondary to DTC during the follow-up. Among these patients, 13 (24.1%) died from the disease. Dedifferentiation characteristics were identified at pathological examination of the metastatic disease (lymph node or distant metastases) and was defined as the abrupt transformation of a well-differentiated tumor into high-grade morphology lacking the original distinct histologic characteristics.

RESULTS

Tumor dedifferentiation marked by cellular aberrations and radioiodine (RAI) therapy resistance occurred in 5 (9.3%) patients. Four of them died due to pulmonary progression (80.0%), and the median survival of this group was 30 months compared to 279 months in the patients without dedifferentiation. The cumulative disease-specific survival was 20.0% in the patients with dedifferentiation during the follow-up versus 46.1% among the cases without this condition (P = .003, log-rank test). Moreover, dedifferentiation was independently associated with shorter disease-specific survival (hazard ratio [HR] = 31.607; 95% confidence interval [CI]: 4.815-207.478; P<.0001, Cox regression model) as were age over 45 years (HR = 10.904; 95% CI: 1.145-103.853; P = .038) and male sex (HR = 4.210; 95% CI: 1.056-16.783; P = .042).

CONCLUSION

DTC patients with pulmonary disease exhibited shorter disease-specific survival, particularly those who developed tumor dedifferentiation, and these patients require special attention during follow-up.

ABBREVIATIONS

CI = confidence interval DTC = differentiated thyroid cancer FTC = follicular thyroid carcinoma HR = hazard ratio IQR = interquartile range LN = lymph node LR = likelihood ratio PTC = papillary thyroid carcinoma RAI = radioiodine pTNM = pathologic tumor-node-metastasis stage system.

pmTOR is a marker of aggressiveness in papillary thyroid carcinomas

BACKGROUND

Activation of the mTOR pathway has been observed in thyroid cancer, but the biologic consequences regarding tumor behavior and patient prognosis remain poorly explored.

METHODS

We aimed to evaluate the associations of the mTOR pathway with clinicopathologic and molecular features and prognosis through the immunocharacterization of pmTOR and pS6 expression (as readouts of the pathway) in a series of 191 papillary thyroid carcinomas.

RESULTS

pmTOR expression was associated with distant metastases (P = .05) and persistence of disease (P = .05). Cases with greater expression of pmTOR were submitted to more ¹³¹I treatments (r[102] = 0.2; P = .02) and a greater cumulative dose of radioactive iodine (r[100] = 0.3; P = .01). Positive pmTOR expression showed to be an independent risk factor for distant metastases (odds ratio = 18.2; 95% confidence interval 2.1-157.9; P = .01). In contrast, pS6 expression was associated with absence of extrathyroid extension (P = .001), well-defined tumor margins (P = .05), and wild-type BRAF status (P = .01). There was no correlation between the expression of pmTOR and pS6 expression (r[140] = 0.1; P = .3).

CONCLUSION

pmTOR expression is an indicator of aggressive, metastatic papillary thyroid carcinoma, being possibly implicated in refractoriness to therapy, while pS6 expression is associated with less aggressive pathologic features. Further studies are needed to understand better the biologic consequences of activation of the mTOR pathway in the behavior of thyroid cancer, namely the contribution of other pmTOR downstream effectors.

Therapeutic options in papillary thyroid carcinoma: current guidelines and future perspectives

The treatment of papillary thyroid cancer is now based on individual patient risk and response to therapies. Molecular techniques are increasingly being used to risk stratify and to guide therapeutic decisions. There have been advances in the treatment of local disease through surgery or radioiodine. Directed techniques can target metastatic disease including bisphosphonates, radiofrequency ablation or radiotherapy. Systemic therapies such as tyrosine kinase inhibitors show great promise although such treatment must be individualized. Future therapies will target treating radioiodine refractory disease.

RISK FACTORS FOR NONREMISSION AND PROGRESSION-FREE SURVIVAL AFTER I-131 THERAPY IN PATIENTS WITH LUNG METASTASIS FROM DIFFERENTIATED THYROID CANCER: A SINGLE-INSTITUTE, RETROSPECTIVE ANALYSIS IN SOUTHERN CHINA

OBJECTIVE

Prognostic factors related to progression-free survival (PFS) have not received much attention in the literature regarding iodine-131 ((131)I) therapy for patients with differentiated thyroid cancer and lung metastases. We sought to explore the factors associated with PFS and nonremission in a group of patients with differentiated thyroid cancer and pulmonary metastases at initial diagnosis and to investigate the impact of (131)I therapy on pulmonary function and peripheral blood counts in the same cohort of patients.

METHODS

The medical records of 1,050 patients with differentiated thyroid cancer treated at the Zhujiang Hospital of Southern Medical University from January 2006 to January 2015 were retrospectively reviewed. Among them, 107 patients fulfilled the inclusion criteria.

RESULTS

Multivariate Cox regression analysis indicated that age ≥45 years and (131)I nonavidity were independent risk factors for disease progression. Multivariate logistic regression analysis revealed that pulmonary nodule size ≥1 cm and (131)I nonavidity were the strongest risk factors predicting nonremission. Varying cumulative (131)I dosage had no association with posttreatment pulmonary function or peripheral blood cell counts.

CONCLUSION

Similar to earlier studies, our results confirm that (131)I nonavidity was associated with an increased risk of disease progression and greater odds of nonremission. In addition, patients with differentiated thyroid cancer and lung metastases with pulmonary nodules ≥1 cm had a reduced likelihood of achieving remission. Furthermore, special attention is needed when monitoring patients over 45 years at a higher risk of disease progression.

ABBREVIATIONS

CI = confidence interval DTC = differentiated thyroid cancer (18)F-FDG = fluoro-18 fluorodeoxyglucose FEF = forced expiratory flow FTC = follicular thyroid cancer FVC = forced vital capacity GR = granulocytes Hb = hemoglobin HR = hazard ratio (131)I = iodine-131 LN = lymph node OR = odds ratio OS = overall survival PET/CT = positive positron emission tomography/computed tomography PFS = progression-free survival PT = partial thyroidectomy PTC = papillary thyroid cancer RAI = radioactive iodine RBC = red blood cell Tg = thyroglobulin TgAb = thyroglobulin antibody TSH = thyroid-stimulating hormone TT = total thyroidectomy WBC = white blood cells WBS = whole body scan.

Prognostic effects of TERT promoter mutations are enhanced by coexistence with BRAF or RAS mutations and strengthen the risk prediction by the ATA or TNM staging system in differentiated thyroid cancer patients

BACKGROUND

Recent reports suggest that mutations in the promoter of the gene encoding telomerase reverse transcriptase (TERT) affect thyroid cancer outcomes.

METHODS

In all, 551 patients with differentiated thyroid cancer (DTC) enrolled in this study. The median follow-up duration was 4.8 years (interquartile range, 3.4-10.6 years).

RESULTS

TERT promoter mutations were detected in 25 DTCs (4.5%): 2.8% in neither BRAF-mutated nor RAS-mutated tumors, 4.8% in BRAF-mutated tumors, and 11.3% in RAS-mutated tumors. Moreover, they were frequently observed in American Thyroid Association (ATA) high-risk and TNM stage III/IV groups (9.1% and 12.9%, respectively). The coexistence of BRAF or RAS with TERT promoter mutations increased aggressive clinicopathologic features, recurrence (hazard ratio [HR] for BRAF, 4.64; 95% confidence interval [CI], 1.42-15.18; HR for RAS, 5.36; 95% CI, 1.20-24.02), and mortality (HR for BRAF, 15.13; 95% CI, 1.55-148.23; HR for RAS, 14.75; 95% CI, 1.30-167.00), even after adjustments for the age at diagnosis and sex, although the significance was lost after additional adjustments for pathologic characteristics. Furthermore, TERT promoter mutations significantly increased the risk of both recurrence and mortality in the ATA high-risk (HR for recurrence, 5.79; 95% CI, 2.07-16.18; HR for mortality, 16.16; 95% CI, 2.10-124.15) and TNM stage III/IV groups (HR for recurrence, 3.60; 95% CI, 1.19-10.85; HR for mortality, 9.06; 95% CI, 2.09-39.26).

CONCLUSIONS

The coexistence of BRAF or RAS mutations enhanced the prognostic effects of TERT promoter mutations. Furthermore, TERT promoter mutations strengthened the predictions of mortality and recurrence by the ATA and TNM staging systems, particularly for high-risk patients with DTC. Cancer 2016;122:1370-1379. © 2016 American Cancer Society.

Outcomes and Prognostic Factors in Radioiodine Refractory Differentiated Thyroid Carcinomas

BACKGROUND

Outcomes vary among patients with radioiodine refractory (RR) differentiated thyroid cancer (DTC). The prognostic factors for survival are not well-known, resulting in difficulty in selecting patients for new targeted therapies. We assessed overall survival (OS) and cancer-specific survival (CSS) from RR-DTC to identify prognostic factors associated with survival.

PATIENTS AND METHODS

The data on all cases of metastatic RR-DTC treated in our center from 1990 to 2011 were retrospectively reviewed. Survival was estimated using the Kaplan-Meier method; associated prognostic factors were assessed using Cox's model.

RESULTS

Of 153 cases of metastatic DTC, 59% (n = 91) met a criterion for RR: that is, 60% (n = 55) had at least 1 metastasis without (131)I uptake; 21% (n = 19) had progressive disease (PD) despite (131)I; 19% (n = 17) had persistent disease despite a cumulative activity of (131)I of ≥600 mCi. After the diagnosis of RR, median OS was 8.9 years (95% confidence interval [CI]: 5.4-NR); median CSS was 9.6 years (95% CI: 6.01-NR). In multivariate analyses, PD despite (131)I as a criterion for RR disease and the time from initial diagnosis of DTC to diagnosis of RR <3 years were the only independent prognostic factors for poor OS and CSS. Thyroglobulin doubling time (Tg-DT) was assessed in 31 of 91 cases. Among the 11 patients with Tg-DT for <1 year or undetectable Tg, 6 deaths occurred, whereas only 3 died of 20 patients with Tg-DT >1 year or negative Tg-DT.

CONCLUSION

The identification of prognostic factors for decreased survival in RR-DTC may improve the selection of patients for targeted agents.

IMPLICATIONS FOR PRACTICE

This study shows a great heterogeneity in terms of prognosis in radioiodine refractory differentiated thyroid carcinoma. Poorer prognosis is observed in patients with tumor progression or with a diagnosis of radioiodine resistance within 3 years after the initial diagnosis of thyroid cancer. Those findings could lead to improvements in the selection of patients for targeted therapies.

Isolated Metastasis in Male Breast from Differentiated Thyroid Carcinoma - Oncological Curiosity. A Case Report and Review of Literature

Papillary carcinomas are the most common thyroid malignancy accounting for approximately 80 % of thyroid cancers (Rosenbaum and McHenry Expert Rev Anticancer Ther 9:317-329, 2009). They generally manifest as solitary nodules in the thyroid with or without cervical lymphadenopathy. Distant metastases though rare, are commonly seen in lungs and bones, other rare sites are parotid, skin, brain, ovary, adrenal, kidney, Pancreas and breast. We herein present an unusual case of breast lump as an initial presentation of a well differentiated thyroid cancer in a male patient. Our case is unique since it presented with isolated breast metastasis in a male patient in the absence of primary diagnosis. This prompted us to report the case with review of literature. A brief review of literature follows.

Pulmonary metastases in differentiated thyroid cancer: efficacy of radioiodine therapy and prognostic factors

CONTEXT

Data from a large cohort of patients with pulmonary metastases from differentiated thyroid cancer (DTC) were retrospectively analyzed.

OBJECTIVE

To assess the effect of radioiodine therapy and investigate the prognostic factors of survival for patients with pulmonary metastasis secondary to DTC.

METHODS

A total of 372 patients with pulmonary metastasis from DTC treated with (131)I entered the study. According to the results of (131)I whole-body scan (WBS), pulmonary metastases were classified as (131)I-avid and non-(131)I-avid. For patients with (131)I-avid lung metastases, treatment response was measured by three parameters: serum thyroglobulin (Tg) levels, chest computed tomography (CT) and post-therapeutic (131)I-WBS. Overall survival was calculated by the Kaplan-Meier method. Factors predictive of the outcome were determined by multivariate analyses.

RESULTS

Among patients demonstrating (131)I-avid pulmonary metastases (256/372, 68.8%), 156 cases (156/256, 60.9%) showed a significant decrease in serum Tg levels after (131)I therapy and 138 cases (138/229, 60.3%) showed a reduction in pulmonary metastases on follow-up CT. A complete cure, however, was only achieved in 62 cases (62/256, 24.2%). Multivariate analysis showed that only age, the presence of multiple distant metastases and pulmonary metastatic node size were significant independent variables between the groups of (131)I-avid and non-(131)I-avid.

CONCLUSION

This study indicated that, most (131)I-avid pulmonary metastases from DTC can obtain partial or complete remission after (131)I therapy. Younger patients (<40 years old) with only pulmonary metastases and small ('fine miliaric' or micronodular) metastases appear to have relative favorite outcomes. Patients who do not respond to (131)I treatment have a worse prognosis.

Prognostic factors in pediatric differentiated thyroid cancer patients with pulmonary metastases

AIM

This study was aimed at identifying the prognostic factors predicting remission in pediatric differentiated thyroid cancer (DTC) patients presenting with pulmonary metastases. Little is known about the prognostic factors in reference to pediatric DTC patients presenting with pulmonary metastases.

METHODS

Fifty-three DTC patients aged ≤21 years were diagnosed with pulmonary metastases at initial presentation. The demographic and disease characteristics were compared between the patients who achieved remission and those who did not.

RESULTS

During the median follow-up of 72 months, 38 patients became disease free, 14 patients had biochemically and/or structurally persistent disease, and one patient died due to disease progression. Patient age >15 years, presence of macronodular pulmonary metastases, and surgical methods lesser than total/near-total thyroidectomy were identified as factors associated with reduced odds of remission.

CONCLUSION

This study describes the disease course and depicts the disease related prognostic factors in pediatric DTC patients with pulmonary metastases.

Changes in the pulmonary function test after radioactive iodine treatment in patients with pulmonary metastases of differentiated thyroid cancer

Objective

Pulmonary function test (PFT) is a useful tool for an objective assessment of respiratory function. Impaired pulmonary function is critical for the survival and quality of life in patients with pulmonary metastases of solid cancers including thyroid cancer. This study aimed to evaluate clinical factors associated with severely impaired pulmonary function by serial assessment with PFT in patients with pulmonary metastasis of differentiated thyroid cancer (DTC) who received radioactive iodine treatment (RAIT).

Patients

This retrospective study enrolled 31 patients who underwent serial PFTs before and after RAIT for pulmonary metastasis of DTC. We evaluated the risk factors for severe impairment of pulmonary function.

Results

The median age of the patients was 44.1 years and 18 of them were female patients. Severe impairment of pulmonary function was observed in five patients (16%) after a median of three RAITs (cumulative I-131 activity = 20.4 GBq). These patients were older and more frequently had mild impairment of baseline pulmonary function, respiratory symptoms, or progressive disease compared with patients with stable pulmonary function. Neither cumulative dose nor number of RAIT was associated with decreased pulmonary function. Coexisting pulmonary diseases, presence of respiratory symptoms, and metastatic disease progression were significantly associated with severe decrease in forced vital capacity during follow-up (p =.047, p =.011, and p =.021, respectively).

Conclusions

Pulmonary function was severely impaired during follow-up in some patients with pulmonary metastasis of DTC after a high-dose RAITs. Neither the number of RAIT nor the cumulative I-131 activity was associated with decreased pulmonary function. Serial PFT might be considered for some high-risk patients during follow-up.

Lung metastases from differentiated thyroid carcinoma: prognostic factors related to remission and disease-free survival

OBJECTIVE

Distant metastases, although rare, account for maximum disease-related mortality in differentiated thyroid cancer (DTC). Lungs and bones are the most frequent sites of metastases. We sought to identify the prognostic factors in adult DTC patients presenting with pulmonary metastases at initial diagnosis.

DESIGN

Retrospective cohort study.

PATIENTS

From the medical records of 4370 patients, 200 patients aged more than 21 years who were identified to have pulmonary metastases at the time of diagnosis were included in the analysis.

RESULTS

The sites of metastases were lungs alone in 133 (67%) patients, and additional sites in remaining 67 (33%) patients were as follows: bones in 59, liver in 4, brain in 2 and both bone and liver in two patients. During the mean follow-up of 61 months (range, 12-312 months), 76 patients achieved remission, 121 (60·5%) patients had biochemically and/or structurally persistent disease and three patients showed disease progression. Multivariate analysis revealed presence of macro-nodular (chest X-ray positive) pulmonary metastases and concomitant skeletal metastases as independent factors decreasing the likelihood of remission. Of the 76 patients with remission, 16 (21%) developed subsequent recurrence. Patient age >45 years and follicular histopathology were independently associated with greater hazards of developing recurrence.

CONCLUSION

This study suggests that the patients with macro-nodular lung metastases and/or concomitant skeletal metastases have reduced odds of achieving remission. Moreover, significant number of patients recur even after complete remission with RAI treatment, hence strict surveillance is recommended especially in patients with age >45 years and/or with follicular histology of DTC.

Synchronous diagnosis of metastatic cancer to the thyroid is associated with poor prognosis

The incidence and histopathological characteristics of metastatic cancers to the thyroid (MCT) are different in various geographic areas. The aim of this study was to elucidate the clinical features of MCT, including histocytological diagnosis and therapeutic outcomes. A retrospective analysis of patients with thyroid cancer treated and followed up at the Chang Gung Medical Center in Linkou was performed. Among 3957 patients with thyroid cancer, a total of 56 patients with MCT were evaluated. Of them, 47 patients (83.9 %) were diagnosed with malignancy or suspected malignancy via fine needle aspiration cytology of the thyroid. Synchronous primary cancers were diagnosed in 44 of the patients with MCT. Of the MCT, metastasis of lung cancer to the thyroid was the leading category. Other primary sites of MCT were the head and neck, gastrointestinal tract, kidneys, breast, cervix, and unknown primary site. The mean 5-, 10-, 20-, and 60-month survival rates were 46.4, 32.1, 21.4, and 7.9 % for the patients. Patients with metachronous thyroid carcinoma had significantly better survival than patients with synchronous cancer. In conclusions, the incidence of MCT in patients with thyroid cancer is low; however, the prognosis of patients with MCT is poor, especially in patients diagnosed with synchronous primary tumors. In this study, MCT commonly originated in organs located near the thyroid, such as the lungs, head, and neck. Close monitoring of these malignancies may improve the prognosis of patients with MCT in the future.

Solitary skin metastasis of papillary thyroid carcinoma

A solitary skin metastasis is a rare manifestation of papillary thyroid carcinoma (PTC). A 55-year-old woman presented with a movable subcutaneous nodule in her anterior neck for several months. Three years ago, she underwent total thyroidectomy and remnant ablation for classical PTC (pT3N0M0) and was under thyroxine suppression therapy without any evidence of recurrent disease. The subcutaneous nodule was 0.4 cm in size, firm, and movable without any change in the overlying skin. Recurrent PTC was confirmed after excision biopsy. Eight months after, she got a new nodule along the previous excision site. After punch biopsy, metastatic PTC was confirmed in the deep dermis and was re-excised with a clear resection margin. This is the first report of a case of solitary skin metastasis of PTC in Korea. Although solitary skin metastasis of PTC is rare, it should be considered in patients with a skin nodule.

Long-term, treatment-free survival in select patients with distant metastatic papillary thyroid cancer

Well-differentiated thyroid carcinoma (WDTC) generally has a favorable prognosis. However, patients with distant metastatic disease experience progression of disease with a higher mortality. A subset of patients not previously described may challenge the conventional dogma regarding the progressive nature of all metastatic WDTC. Through analysis of our database, we identified patients with distant metastatic WDTC and persistent, minimally progressive disease. In all patients, persistent metastatic disease was confirmed via tissue biopsy, abnormal PET scan, and/or biochemical elevations in thyroglobulin or antibody levels. Progression of disease was monitored clinically and with repeat imaging. We describe five patients with WDTC and pulmonary metastases, aged 8-43 years at diagnosis. All patients underwent initial surgery and radioactive iodine (RAI) ablation, with some receiving multiple treatments. Persistent pulmonary metastatic disease was confirmed over decades (mean 22 years, range 8-42 years) with minimal progression despite no further treatment beyond thyroid hormone suppression. Persistent disease was biopsy-proven in all patients at a mean of 9.6 years from last RAI treatment. All patients had elevated thyroglobulin or anti-thyroglobulin antibody levels, while three demonstrated metabolically active disease with positive FDG uptake on PET scan, and one patient with persistent radioactive iodine avid pulmonary metastasis 36 years after her last RAI treatment. This case series demonstrates that some patients with distant metastases, even if metabolically active and radioactive iodine resistant, remain stable for decades without further treatment. Clinical awareness of such patients and continual reassessment of disease risk following initial therapy are crucial as aggressive treatment may not be necessary.

Multi-organ distant metastases confer worse disease-specific survival in differentiated thyroid cancer

BACKGROUND

Differentiated thyroid cancer (DTC) is usually associated with an excellent prognosis. With appropriate management of disease in the neck, death from thyroid cancer is more commonly related to the impact of distant metastases rather than locoregional recurrence. However, many patients with distant metastases can have very long periods of progression-free survival. The aims of this study were to determine the impact of single and multi-organ distant metastases (SODM and MODM) on survival, and identify factors that predict SODM progressing to MODM.

METHODS

An institutional database of 3664 previously untreated patients with DTC who had surgery between 1986 and 2010 was reviewed. One hundred and twenty-five (3.4%) patients developed distant metastases, of whom 93 developed SODM and 32 MODM. Overall survival was determined for each group by the Kaplan-Meier method. Factors predictive of MODM were identified by univariate and multivariate analysis. Multi-organ recurrence-free survival (MORFS) is a measure of SODM progressing to MODM disease. MORFS was calculated from the time of first distant metastasis to the time of second organ involvement by distant metastases.

RESULTS

The median age was 56 years (range 5-86 years). The median follow-up was 77 and 79 months (range 2-318 months) for the SODM and MODM groups respectively. SODM patients had five-year survival of 77.6% from the time of first distant metastasis, whereas MODM patients had a significantly poorer survival of just 15.3% from the time of second organ distant metastasis to death (p<0.001). The median time from first to second distant metastasis was 14.7 months (range 1-121 months). Seventy-one (57%) patients had M1 disease at presentation. Being aged ≥ 45 years (p = 0.05) and having an unstimulated serum thyroglobulin (Tg) level of ≥ 30 ng/mL at the time of diagnosis of initial distant metastasis (p<0.001) were univariate predictors of developing MODM. Controlling for age, an unstimulated serum Tg level of ≥ 30 ng/mL conferred a hazard ratio of 5.77 ([CI 2.13-15.64]; p = 0.001) for diagnosis of MODM.

CONCLUSIONS

MODM are associated with a poorer survival compared to patients with SODM. A serum Tg level >30 ng/mL at the time of first distant metastases confers more than a fivefold risk of having MODM identified during follow-up.

Differentiated thyroid cancer in patients over 60 years of age at presentation: a retrospective study of 438 patients

OBJECTIVES

The aim of this study is to identify the prognostic factors predicting remission and subsequent disease relapse in patients with differentiated thyroid cancer (DTC) greater than 60years of age.

MATERIALS AND METHODS

The institute thyroid cancer database had 4370 patients with DTC, of which 447 (10%) were aged>60. However, 9 patients were excluded due to follow-up less than 1year. The prognostic factors in the remaining 438 patients were studied.

RESULTS

Among the 438 patients, 311 (71%) had only loco-regional disease (M0) and 127 (29%) had distant metastases (M1) at the time of initial presentation. The host factors predictive of distant metastases at presentation were female gender, primary tumor size (>4cm), follicular histology, and extra-thyroidal extension. Among Mo patients, 195 (63%) achieved complete remission while only 12 (9%) M1 patients did so. Average number of radioactive iodine ((131)I) doses administered to achieve complete remission was 2.3 (range, 1-6) and the mean cumulative dose was 3404MBq (range, 925-46,250MBq). In multivariate logistic regression among M0 patients, follicular histology, nodal metastases, and surgical treatment lesser than total/near-total thyroidectomy and among M1 patients, site of distant metastases (skeletal and multiple sites) were independent factors predicting non-remission. Among the patients (both M0 and M1) who achieved remission, factors associated with disease recurrence were primary tumor size (>4cm), nodal metastases, pulmonary metastases, and non-remission after first dose of radioactive iodine and were associated with greater chances of disease relapse.

CONCLUSION

This study highlights that DTC in older patients behaves more aggressively than in adults age<60years, and identifies several prognostic factors for remission and subsequent relapse.

Clinical significance of diffuse intrathoracic uptake on post-therapy I-131 scans in thyroid cancer patients

PURPOSE

The purpose of this study was to identify the frequency and possible cause of diffuse intrathoracic uptake on post-therapy I-131 scans in thyroid cancer patients.

METHODS

We retrospectively reviewed 781 post-therapy scans of 755 thyroid cancer patients who underwent total thyroidectomy and radioactive iodine therapy between January and December 2010. Diffuse intrathoracic uptake on post-therapy scans was examined, and clinical patient characteristics including sex, age, regimen for thyroid-stimulating hormone (TSH) stimulation (thyroid hormone withdrawal or recombinant human TSH injection), TSH, thyroglobulin (Tg) and anti-thyroglobulin antibody (anti-Tg Ab) levels, therapeutic dose of radioactive iodine therapy and prior history of radioactive iodine therapy were recorded.Scan findings were correlated with chest CT, chest radiographs, laboratory tests and/or clinical status. Diffuse intrathoracic uptake without evidence of pathologic condition was categorized as indeterminate. The association between clinical characteristics and intrathoracic uptake were analyzed for negative intrathoracic uptake and indeterminate uptake groups.

RESULTS

Diffuse intrathoracic uptake on post-therapy scans was demonstrated in 39 out of 755 (5.2 %) patients, among which 3 were confirmed as lung metastasis. The 14 patients that showed high Tg or anti-Tg Ab levels were considered to be at risk of having undetected micrometastasis on other imaging modalities. The remaining 22 were indeterminate (2.9 %).Upon comparison of negative intrathoracic uptake and indeterminate uptake groups, TSH stimulation by thyroid hormone withdrawal was shown to be significantly correlated with diffuse intrathoracic uptake (p < 0.05).

CONCLUSION

The frequency of diffuse intrathoracic uptake on post-therapy scans was 5.2 % and could be seen in thyroid cancer patients with underlying lung metastasis as well as those without definite pathologic condition. In the latter, there was a higher frequency for diffusely increased intrathoracic uptake in those who underwent thyroid hormone withdrawal rather than recombinant human TSH injection.