Second primary malignancies following thyroid cancer: a population-based study in Taiwan

Causal effect of thyroid cancer on secondary primary malignancies: findings from the UK Biobank and FinnGen cohorts

Background

Existing epidemiological data indicated a correlation between thyroid cancer (THCA) and the risk of secondary primary malignancies (SPMs). However, the correlation does not always imply causality.

Methods

The Mendelian randomization (MR) analyses were performed to investigate the causal relationships between THCA and SPMs based on international multicenter data. Odds ratios (ORs) with 95% confidence intervals (95% CIs) were calculated. The Cancer Genome Atlas (TCGA) was used to explore potential mechanisms shared by THCA and bladder cancer (BLCA).

Results

Summary datasets of genome-wide association studies (GWAS) on 30 types of cancers were obtained from the United Kingdom Biobank (UKB) and FinnGen database. Meta-analysis of the UKB and FinnGen results revealed that THCA was significantly positively correlated with BLCA (OR = 1.140; 95% CI, 1.072-1.212; P < 0.001). Four genes, including WNT3, FAM171A2, MLLT11, and ULBP1, were identified as key genes shared by both TCHA and BLCA. Correlation analysis indicated that THCA may increase the risk of secondary BLCA through augmentation of N2 neutrophil infiltration.

Conclusions

This study showed that THCA was causally related to BLCA. It is recommended to conduct more rigorous screenings for BLCA during the follow-up of THCA patients.

Decision Variables for the Use of Radioactive Iodine in Patients with Thyroid Cancer at Intermediate Risk of Recurrence

The use of radioactive iodine (RAI) after total thyroidectomy for patients at the American Thyroid Association (ATA) who are at intermediate risk of recurrence is controversial. This is due to the lack of prospective randomized trials proving a benefit to recurrence or survival of RAI therapy in this group. In the absence of such evidence, clinicians struggle to recommend for or against this therapeutic approach which frequently results in overtreatment. This review describes key elements in the decision-making process that help clinicians more comprehensively evaluate the need for RAI therapy in patients with thyroid cancer at intermediate risk of recurrence. A clear definition of the purpose of RAI therapy should be conveyed to patients. In this sense, adjuvant RAI therapy intends to decrease recurrence, and ablation therapy is used to facilitate surveillance. Better stratification of the intermediate risk category into a low-intermediate subgroup and an intermediate-high-risk subgroup results in less heterogeneity and a more precise prediction of recurrence risk. The evaluation of post-operative thyroglobulin levels may prevent the overtreatment of low-intermediate-risk patients when their thyroglobulin level is <2.5 ng/mL. the integration of tumor genomics (when available) alongside pathologic features can enhance the ability of the clinician to predict iodine concentration in thyroid cancer cells. Finally, a detailed consideration of the adverse effects of RAI, patients' comorbidities, and patient preferences will result in a patient-centered personalized approach. Systematic examination of these variables will ultimately provide a framework for making more educated decisions on the use of RAI in patients at intermediate risk of recurrence that will prevent overtreatment and minimize harm.

Risk prediction of second primary malignant tumor in primary differentiated thyroid cancer patients: a population-based study

PURPOSE

To investigate the risk factors of second primary malignant tumor (SPMT) in patients with differentiated thyroid cancer (DTC) and establish a competing risk nomogram to predict the probability of SPMT occurrence.

METHODS

We retrieved data from the Surveillance, Epidemiology, and End Results (SEER) database for patients diagnosed with DTC between 2000 and 2019. The Fine and Gray subdistribution hazard model was employed to identify SPMT risk factors in the training set and develop a competing risk nomogram. Model evaluation was performed using area under the receiver operating characteristic curve (AUC), calibration curve, and decision curve analysis (DCA).

RESULTS

A total of 112,257 eligible patients were included in the study and randomized into a training set (n = 112,256) and a validation set (n = 33,678). The cumulative incidence rate of SPMT was 15% (n = 9528). Age, sex, race, tumor multifocality, and TNM stage were independent risk factors of SPMT. The calibration plots showed good agreement between the predicted and observed SPMT risks. The 10-year AUCs of the calibration plots were 70.2 (68.7-71.6) in the training set and 70.2 (68.7-71.5) in the validation set. Moreover, DCA showed that our proposed model resulted in higher net benefits within a defined range of risk thresholds. The cumulative incidence rate of SPMT differed among risk groups, classified according to nomogram risk scores.

CONCLUSION

The competing risk nomogram developed in this study exhibits high performance in predicting the occurrence of SPMT in patients with DTC. These findings may help clinicians identify patients at distinct levels of risk of SPMT and develop corresponding clinical management strategies.

Impact of thyroid hormone replacement on the risk of second cancer after thyroidectomy: a Korean National Cohort Study

We aimed to investigate the effect of thyroid hormone administration on the risk of second primary cancer in patients who underwent thyroidectomy for differentiated thyroid cancer. Data were extracted from the medical billing data of the Health Insurance Review and Assessment Service in South Korea. Patients between 19 and 80 years old who underwent thyroid surgery at least once between January 2009 and June 2020 were included. Data of patients with second primary cancer and control patients with matched age, sex, operation date, and follow-up duration were extracted at a ratio of 1:4. A nested case-control analysis was performed to exclude length bias to confirm the correlation between the duration of thyroid hormone administration, dose, and incidence of second primary cancer. Of the 261,598 patients who underwent surgery for thyroid cancer included in the study, 11,790 with second primary cancer and 47,160 without second primary cancer were matched. The average dose of thyroid hormone increased the adjusted odds ratio (OR) for both low (≤ 50 μg, OR 1.29, confidence interval (CI) 1.12-1.48) and high (< 100 μg, OR 1.24, CI 1.12-1.37) doses. Analyzing over time, the adjusted OR of second primary cancer increased, especially in short (≤ 1 year) (OR 1.19; CI 1.06-1.34) and long (> 5 years) duration (OR 1.25; CI 1.10-1.41). In conclusion, insufficient and excessive thyroid hormone replacement might be linked to increased second primary cancer in patients who underwent thyroidectomy for differentiated thyroid cancer.

Second Primary Cancer Among Patients With Papillary Thyroid Carcinoma Following the Chernobyl Disaster

Importance

To our knowledge, there are no complete population-based studies of the risks of developing second malignant tumors after papillary thyroid carcinoma (PTC) in patients following the Chernobyl nuclear accident.

Objective

To study the risk of second primary cancers in patients with PTC after the Chernobyl disaster.

Design, Setting, and Participants

This was a retrospective cohort study conducted in the Republic of Belarus over a 31-year time frame evaluating patients with primary PTC and second malignant tumors. Personal data from the Belarussian Cancer Registry were used in the investigation, and only second primary cancers were included in the analysis. Patients were observed from January 1, 1990, to December 31, 2021, for the establishment of second primary malignant tumors.

Main Outcomes and Measures

For analysis, synchronous and metachronous tumors were grouped into 1 group (second primary cancer group). If the patient had more than 2 cancers, they were observed until development of a second tumor and, subsequently, the development of a third tumor. The starting point for calculating the number of person-years was the date of thyroid cancer diagnosis. The end point for calculating the number of person-years was the date of diagnosis of the second primary malignant tumor, the date of death, the date of the last visit of the patient, or December 31, 2021 (the end the of study period). The incidence of a second primary malignant tumor with PTC was calculated for the study groups using standardized incidence ratios.

Results

Of the 30 568 patients with a primary PTC included in this study, 2820 (9.2%) developed a second malignant tumor (2204 women and 616 men); the mean (SD) age of all patients at time of the primary cancer was 53.9 (12.6) years and at time of the secondary cancer was 61.5 (11.8) years. Overall, the standardized incidence ratio was statistically significant for all types of cancer (1.25; 95% CI, 1.21-1.30), including solid malignant tumors (1.20; 95% CI, 1.15-1.25) and all leukemias (1.61; 95% CI, 2.17-2.13). Cancers of the digestive system (466 cases [21.1%]), genital organs (376 cases [17.1%]), and breasts (603 cases [27.4%]) were the most prevalent second primary tumors in women following PTC. Second primary tumors of the gastrointestinal tract (146 cases [27.7%]), genitourinary system (139 cases [22.6%]), and urinary tract (139 cases [22.6%]) were the most prevalent in men. Urinary tract cancers (307 cases [10.9%]) and gastrointestinal tumors (612 cases [21.4%]) were the most prevalent second primary tumors overall.

Conclusions and Relevance

This cohort study reports the increased incidence of solid secondary tumors in men and women over a 31-year time frame after the Chernobyl disaster. Moreover, there was a statistically significant increased risk of second tumors of the breast, colon, rectum, mesothelium, eye, adnexa, meninges, and adrenal glands as well as Kaposi sarcoma. These data might have an effect on the follow-up of this cohort of patients to detect secondary malignant tumors at an early stage.

Effects of radioactive iodine on clonal hematopoiesis in patients with thyroid cancer: A prospective study

OBJECTIVE

Exposure to therapeutic radioactive iodine (RAI) is associated with an increased relative risk of myeloid malignancies. Clonal hematopoiesis (CH) is a precursor state that can be detected in blood of healthy individuals decades before overt development of leukemia. We prospective studied the effects of RAI on CH.

DESIGN

Prospective cohort study.

PATIENTS AND MEASUREMENTS

We examined the effect of RAI on CH in 20 patients exposed to RAI for thyroid carcinoma and 20 age-matched unexposed controls. CH status was determined at baseline, 6, 12, 18 and 24 months. We also examined the effect of CH on structural progression of disease.

RESULTS

No CH mutations were observed in the patient population that were not present at baseline. Using a variant allelic fraction (VAF) of 2% to define CH, 6/20 older patients (55-80 years old) had CH compared to 2/20 younger patients (20-40 years old) (p = 0.11). Six patients exposed to RAI had CH compared to two patients not exposed to RAI (30% vs. 10%, p = 0.11). There was no significant difference in CH VAF increase in patients treated with RAI compared to untreated age-matched controls (3.8% vs. 1.2%, p = 0.2). CH was significantly associated with somatic BRAFV600E mutations and with worse progression-free survival in the overall cohort as well as among BRAFV600E-mutant tumors.

CONCLUSIONS

There was no increase in CH in patients treated with RAI over a 2-year follow-up period. Larger studies with longer follow-up periods are needed to investigate the association between RAI and clonal dynamics. The presence of CH is associated with worse structural progression in both BRAFV600E-mutant and wild-type thyroid cancers.

Risk of second primary lung cancer in patients with thyroid cancer: a meta-analysis based on big population studies

BACKGROUND

Previous studies have revealed that the number of cancer survivors developing a second primary malignancy is increasing, especially among thyroid cancer patients, and lung cancer is still the main cause of cancer death. Therefore, we aimed to investigate the risk of second primary lung cancer (SPLC) in patients with thyroid cancer.

METHODS

We searched the PubMed, Web of Science, Embase, and Scopus databases up to November 24, 2021, for relevant research and merged the standardized incidence ratios (SIRs) and 95% confidence intervals (95% CIs) to evaluate the risk of developing SPLC in patients with thyroid cancer.

RESULTS

Fourteen studies involving 1480,816 cases were included in our meta-analysis. The pooled result demonstrated that thyroid cancer patients may have a higher risk of SPLC than the general population (SIR = 1.21, 95% CI: 1.07-1.36, P < 0.01, I2 = 81%, P < 0.01). Subgroup analysis stratified by sex indicated that female patients may have a markedly higher risk of SPLC than male patients (SIR = 1.65, 95% CI: 1.40-1.94, P < 0.01, I2 = 75%, P < 0.01).

CONCLUSIONS

Thyroid cancer patients are more likely to develop SPLC than the general population, especially women. However, other risk factors must be investigated, and more prospective studies are needed to confirm our results.Registration: International Prospective Register of Systematic Reviews: No. CRD42021285399.

Links between Breast and Thyroid Cancer: Hormones, Genetic Susceptibility and Medical Interventions

Breast and thyroid glands are two common sites of female malignancies. Since the late 19th century, physicians have found that the cancers in either thyroid or mammary gland might increase the risk of second primary cancers in the other site. From then on, many observational clinical studies have confirmed the hypothesis and more than one theory has been developed to explain the phenomenon. Since the two glands both have secretory functions and are regulated by the hypothalamic-pituitary axis, they may share some common oncogenic molecular pathways. However, other risks factors, including medical interventions and hormones, are also observed to play a role. This article aims to provide a comprehensive review of the associations between the two cancers. The putative mechanisms, such as hormone alteration, autoimmune attack, genetic predisposition and other life-related factors are reviewed and discussed. Medical interventions, such as chemotherapy and radiotherapy, can also increase the risk of second primary cancers. This review will provide novel insights into the research designs, clinical managements and treatments of thyroid and breast cancer patients.

Use of multikinase inhibitors/lenvatinib in patients with synchronous/metachronous cancers coinciding with radioactive-resistant differentiated thyroid cancer

This review focuses on patients with differentiated thyroid carcinoma (DTC) associated with multiple primary malignant neoplasm (MPMN) treated by multikinase inhibitors (MKIs) as systemic treatment for advanced disease. Despite the increasing frequency of MPMNs (many at an advanced stage) and the usefulness of MKIs for multiple metastatic cancers, published data on the management of MPMN and MKI therapies in this scenario are scarce. There are infrequent descriptions of patients with advanced MPMN treated with MKIs, but only a few have described advanced DTC. The management of MPMNs, including DTC and its particular circumstances, is reviewed, focusing on the evidence for MKI therapies. Some considerations for MPMN patients with advanced DTC are discussed, with the intention of helping physicians make decisions in these challenging situations and improving treatment and patient outcomes.

Non-thyroidal second primary malignancy in papillary thyroid cancer patients

INTRODUCTION

The occurrence of non-thyroidal second primary malignancy (NTSPM) in patients with papillary thyroid cancer (PTC) is well documented, but epidemiological data are conflicting.

OBJECTIVE

The aim of this study was to evaluate the incidence of NTSPM in a large series of patients with PTC and to assess its potential risk factors.

METHODS

Single-center cohort study with retrospective data collection conducted on consecutive PTC patients diagnosed from 1988 to 2018 with a minimum follow-up time of 2 years. NTSPM was defined as any primary malignancy with histological confirmation occurring in an anatomical site other than the thyroid. According to the timing of occurrence, NTSPM were subdivided into anachronous, synchronous or metachronous (diagnosed >6 months before, within 6 months and >6 months after PTC diagnosis, respectively).

RESULTS

We included 773 individuals (83.3% females), median age at PTC diagnosis was 47.0 (IQR: 37.0-58.0) years and median follow-up time was 9.9 (6.2-16.3) years. Incidence of NTSPM was 15.5% (n = 120) and its standard incidence ratio (SIR) was higher when compared to the general population (SIR: 2.70). Family history of malignancy and younger age at diagnosis were associated respectively with 206 and 4% increased risk of developing metachronous neoplasia (HR: 2.06 (95% CI: 1.10-3.86) and 1.04 (95% CI: 1.02-1.05), respectively).

CONCLUSION

In our series, the occurrence of NTSPM was not uncommon and its incidence was higher compared to the general population. First-degree family history of malignancy was a strong risk factor for multiple primary malignancies.

Age-related risk for second breast cancer and gynecological malignant neoplasms after differentiated thyroid cancer

PURPOSE

In this study, we aimed to investigate the age-related risk of second breast cancer (SBC) and second gynecological malignant neoplasms (SGMNs) in female differentiated thyroid cancer (DTC) survivors by utilizing the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

A total number of 55,622 female DTC patients were identified between 1975 and 2016, including 2168 patients who developed SBC and SGMNs. The Fine and Gray model was used to calculate the cumulative incidence and sub-distribution hazards ratios (SHR). Poisson regression analysis was employed to calculate the relative risk (RR) and standardized incidence ratio (SIR). Kaplan-Meier survival and log-rank test analyses were also performed.

RESULTS

The overall 40-year cumulative incidence of SBC and SGMNs was 18.9%. Their incidence in the adolescent and young adults (AYA) group increased slowly in the first 30 years, but then was rapidly elevated in the last decade. It increased gradually in the middle-aged adults group and in the first 25 years in the older adults group, but it scarcely increased thereafter. Both the middle-aged adults (adjusted SHR, 2.09; RR, 1.76) and the older adults (adjusted SHR, 1.32; RR, 1.58) groups had higher risks of developing combined SBC and SGMNs than the AYA group. The risks increased mainly in the early latency period. The three groups also had higher SIRs than the US general population. Besides, the best survival after SBC and SGMNs was observed in the AYA group.

CONCLUSIONS

Age was an independent risk factor for SBC and SGMNs incidences among female DTC survivors.

Risk factors for second primary malignancies following thyroid cancer: a nationwide cohort study

OBJECTIVE

Thyroid cancer survivors have a high risk of second primary malignancies (SPMs). We aimed to evaluate the site-specific incidence, prognosis, and risk factors for metachronous SPMs following thyroid cancer.

DESIGN

A nationwide cohort study.

METHODS

This study included data from the Korea National Health Insurance Service (between 2002 and 2018). Exposure to diagnostic radiation was defined by the number of computed tomography (CT) and positron emission tomography-CT scans after the index date. A cumulative radioactive iodine (RAI) dose >100 mCi was considered high-dose RAI.

RESULTS

During the median 6 years of follow-up, among 291 640 patients, 13 083 (4.5%) developed SPMs. Thyroid cancer survivors had a 26% increased risk of SPMs compared with the general population (standardized incidence ratio: 1.26; 95% CI: 1.22-1.29). Furthermore, those with SPMs had a significantly poorer survival rate than those without SPMs (hazard ratio: 11.85; 95% CI: 11.21-12.54; P < 0.001). Significantly elevated risks were observed in myeloid leukemia and 13 solid cancer sites: lip, salivary gland, small intestine, larynx, lung, mediastinum and pleura, mesothelium, breast, corpus uteri, ovary, prostate, kidney, and bladder. Frequent diagnostic medical radiation exposure and high-dose RAI therapy were independent risk factors for several SPMs, including the cancer of salivary gland, lung, mediastinum and pleura, breast, kidney, and bladder, as well as myeloid leukemia.

CONCLUSIONS

Frequent diagnostic radiation exposure and high-dose RAI therapy are independent risk factors for SPM following thyroid cancer. Clinicians need to consider minimizing unnecessary diagnostic radiation exposure and administering a high dose RAI only when justified in patients with thyroid cancer.

Repeat thyroid FNAC: Inter-observer agreement among high- and low-volume centers in Naples metropolitan area and correlation with the EU-TIRADS

Our institution (University Hospital "L. Vanvitelli" - Naples, Italy) is a high-volume (HV) center in Naples metropolitan area and many patients are referred there to repeat thyroid fine-needle aspiration cytology (FNAC) after initial FNAC performed in low-volume institutions (LV). The aims of the study were to 1) examine the inter-observer agreement between HV and LV institutions according to the Italian thyroid cytology system, and 2) explore how the discordant FNAC reports were distributed in the European Thyroid Imaging and Reporting Data System (EU-TIRADS) categories. All consecutive cases of repeat FNAC performed at University Hospital "L. Vanvitelli" from January 2016 to December 2021 were retrospectively reviewed. Fleiss' kappa (κ) was used to assess the inter-observer agreement, and categorical variables were compared by chi-square testing. P < 0.05 was considered statistically significant. A total of 124 nodules from 124 adults (mean age 49 years; mean maximum diameter 19 mm) were evaluated. Initial FNAC reports at LV were: 4 (3.2%) TIR1c, 64 (51.6%) TIR2, 48 (38.7%) TIR3A, 8 (6.5%) TIR3B, 0 TIR4, 0 TIR5. The overall FNAC reports were significantly different between the LV and HV institutions. At repeated FNAC, cytological diagnosis was unchanged in 64 (51.6%) cases including TIR2 and TIR3A results. A downgraded FNAC diagnosis (i.e., TIR2 vs TIR3A, TIR2 vs TIR3B) was observed in 36 (29%) nodules. An upgraded FNAC diagnosis (i.e., TIR3B vs TIR2, TIR3B vs TIR3A, TIR4 vs TIR3A, TIR5 vs TIR2, TIR5 vs TIR3B) was recorded in 24 (19.4%) nodules. The weighted inter-observer agreement between LV and HV institutions was poor (κ=0.133). Changed FNAC results were significantly (p=0.0023) more frequent in nodules at intermediate/high-risk (i.e., EU-TIRADS 4/5) than in those at no/low risk (EU-TIRADS 2/3) [i.e., 32/48 (66.7%) and 28/76 (36.8%), respectively]. Downgraded FNAC results were significantly more frequent in EU-TIRADS 2/3 (p=0.001) while upgraded FNAC were present only in EU-TIRADS 4/5 (24/24, 100.0%). The inter-observer agreement among LV and HV thyroid services was poor. The EU-TIRADS 4 and 5 categories included all the malignant nodules with FNAC results reclassified as higher risk (i.e., TIR3B-TIR4-TIR5) by the high-volume cytology service.

Co-Occurrence of Differentiated Thyroid Cancer and Second Primary Malignancy: Correlation with Expression Profiles of Mismatch Repair Protein and Cell Cycle Regulators

Simple Summary

Although the incidence of thyroid cancer is increasing, improvements in treatment have resulted in more patients being confirmed to have a second primary cancer. However, studies on potential biomarkers for predicting the risk of second primary malignancy are extremely limited. Therefore, our objective was to establish molecular biomarkers for the risk prediction of second primary malignancy using routinely collected formalin-fixed paraffin-embedded tissue specimens. Our results suggest that the deficient mismatch repair phenotype, the expression of pRb, and the lack of CDK4 or CDK6 are significantly associated with co-occurrence of nonthyroid malignancy. The predictive value of these immunohistochemical profiles for the co-occurrence of nonthyroid malignancy was also assessed. The combined evaluation of a four-biomarker signature model may provide the most important predictive innovation. Our study proposes the first tissue-based screening tool for risk stratification and further active surveillance in patients with thyroid cancer.

Abstract

Some patients with thyroid cancer develop a second primary cancer. Defining the characteristics of patients with double primary cancers (DPCs) is crucial and needs to be followed. In this study, we examine molecular profiles in DPC. We enrolled 71 patients who received thyroid cancer surgery, 26 with single thyroid cancer (STC), and 45 with DPC. A retrograde cohort was used to develop immunohistochemical expressions of mismatch repair (MMR) proteins and cell-cycle-related markers from tissue microarrays to produce an equation for predicting the occurrence of DPC. The multivariate logistic model of 67 randomly selected patients (24 with STC and 43 with DPC) identified that the expression of deficient MMR (dMMR) (odds ratio (OR), 10.34; 95% confidence interval (CI), 2.17–49.21) and pRb (OR, 62.71; 95% CI, 4.83–814.22) were significantly associated with a higher risk of DPC. In contrast, the expression of CDK4 (OR, 0.19; 95% CI, 0.04–0.99) and CDK6 (OR, 0.03; 95% CI, 0.002–0.44) was significantly associated with a lower risk of DPC. Collectively, dMMR, pRb, CDK4, and CDK6 have a sensitivity of 88.9% (95% CI, 75.1–95.8) and a specificity of 69.2% (95% CI, 48.1–84.9) for occurrence of DPC in all 71 patients. This is the first report to demonstrate the molecular differentiation of STC and DPC. Overall, the integral molecular profile performed excellent discrimination and denoted an exponential function to predict the probability of DPC.

Thymic Carcinomas and Second Malignancies: A Single-Center Review

Simple Summary

Thymic carcinoma (TC) is a rare neoplasm that accounts for less than 0.01% of all tumors. The aim of our retrospective observational analysis is to review the incidence of second cancers associated with this histological type of cancer. We identified 92 patients with TC referred to our consultation practice and reviewed their clinical data for diagnosis of another cancer pre- or post-diagnosis of TC. This resulted in identification of 14 patients with additional cancers. The incidence of second cancer is similar to that observed in thymomas.

Abstract

Thymic carcinomas account for less than 0.01% of new cancer diagnoses annually and are more aggressive than thymomas. Autoimmune disorders have been associated with thymomas and only recently with thymic carcinomas. Second malignancies are well described after thymomas. The aim of this study was to analyze the incidence of second malignancies in patients with thymic carcinomas. All cases of thymic carcinomas were identified from the pathology archives of Indiana University. Histological materials were reviewed and further correlated with clinical data to identify incidence of second cancers in patients with thymic carcinomas. Histological material was available for review in 92 cases of thymic carcinoma. Clinical data were available for 85 patients. Fourteen of these (16.5%) patients had a second malignancy; these included small cell lung carcinoma, “testicular cancer”, embryonal carcinoma, seminoma, breast carcinoma (two cases), prostatic adenocarcinoma, Hodgkin’s lymphoma, thyroid carcinoma, bladder carcinoma (two cases), renal cell carcinoma, and melanoma. The latter could precede, be concurrent with, or follow the diagnosis thymic carcinoma. The incidence of second cancers in patients with thymic carcinomas is similar to that reported for thymomas. Abnormalities in immunological surveillance may be responsible for this high incidence of second malignancies in thymic tumors.

Thyroid disease is associated with an increased risk of breast cancer: a systematic review and meta-analysis

BACKGROUND

This study investigated the relationship between thyroid diseases and the risk of breast cancer (BC). Clarifying this issue can help medical staff perform of early prevention, diagnosis and treatment for breast cancer patients.

METHODS

The meta-analysis combined data from cohort studies and case-control to obtain a comprehensive result of the relationship between thyroid diseases and risk of BC. We comprehensively searched PubMed, EMbase, Web of Science, and the Cochrane Library. The search period was from the establishment of the databases to August 2020. Literature was collected and screened individually by two reviewers. There was English language restriction on the search and unpublished literature was excluded. The Newcastle-Ottawa Scale (NOS) was used to evaluate the quality of the selected studies prior to data extraction. The data collected included country, author, year of publication, research type, and number of cases. In cases where the data and study heterogeneity permitted, meta-analyses were performed, and odd ratios (ORs) with corresponding 95% confidence intervals (CIs) were calculated. Data were analyzed using the STATA 15.1 software.

RESULTS

A total of 21 articles were included in this study. Hyperthyroidism, thyroid cancer, thyroglobulin antibody (TGAb) levels, and thyroid microsomal antibody (TPOAb) levels were all significantly associated with an increased risk of BC, while hypothyroidism was associated with a reduced risk of BC.

CONCLUSIONS

This study demonstrated that hyperthyroidism, autoimmune thyroiditis (AITD), and thyroid cancer are significantly associated with an increased risk of BC, while hypothyroidism is associated with a reduced risk of BC.

Second primary malignancies in patients with papillary thyroid carcinoma after effect of post-chernobyl irradiation: A risk analysis of more than two decades of observations

BACKGROUND

Second primary malignancy in patients with papillary thyroid carcinoma after Chernobyl accident is an emerging problem. The aims of the study are to investigate the rates and distribution of second primary malignant tumours in Belarus survivors of post-Chernobyl papillary thyroid carcinoma and the cumulative rate of developing a second primary malignancy in a group of patients with metachronous second primaries.

METHODS

Patients aged 18 or younger at the time of Chernobyl accident who were diagnosed with papillary thyroid carcinoma after 1986 were identified from the Belarus Cancer Registry. The clinical and demographic of these patients were analysed to correlate with the factors for the development of secondary primary cancer.

RESULTS

Secondary primary cancer was detected in 1.8 % (119 of 6559) of the patients with papillary thyroid carcinoma. The cumulative incidence tended to rise with increasing age of the cohort and varied depending on the sex of patients. In female patients, breast carcinoma and genital tract carcinomas prevailed, in men patients - lymphoma/ leukaemia and the alimentary tract malignancies predominated. A significant excess risk was revealed for breast carcinoma in females, colon carcinoma in males, and the urinary system carcinomas in males (absolute excess risk [AER] = 3.23, 3.01 and 2.17 correspondingly). Overall, our results pointed to the increased risk of new solid primaries in females, males and both genders (AER = 3.31, 7.19, 4.28 correspondingly) as well as increase risk of lymphoid/hematopoietic malignancies in females and both genders (AER = 1.24) and leukaemia in male patients (AER = 1.45).

CONCLUSION

Patients with papillary thyroid carcinoma after Chernobyl accident are at risk of secondary primary malignancy. Awareness and screening of secondary cancer is needed for patients with papillary thyroid carcinoma after Chernobyl accident.

Analysis of overall survival in differentiated thyroid cancer patients with double primary malignancy

Differentiated thyroid cancer (DTC) survivors are at increased risk of developing double primary malignancy (DPM). The aim of this study was to investigate clinicopathological characteristics and survival in DTC patients diagnosed with DPM. A total of 975 patients with DTC diagnosed between 2013 and 2017, treated, and followed at a medical center in Taiwan were retrospectively reviewed. Data from enrolled patients were analyzed for differences in prognosis dependent on the presence of DPM, and which clinicopathological variables affected their prognosis. Among 975 thyroid cancer patients, 94 (9.6%) were diagnosed with DPMs and 16 (1.6%) patients died of any cause. DPM patients had a greater proportion of males, had a higher mean age, more commonly presented with a thyroid mass incidentally by imaging and cervical lymph node metastases, showed a more advanced thyroid cancer stage, and had a higher proportion of lymph node metastases. Overall survival (OS) was significantly lower in patients diagnosed with DPM. Male gender (hazard ratio [HR] = 4.597), two or more DPMs (HR = 8.071), and shorter time interval between two cancers occurrences (HR = 7.101) were significantly risk factors for DPM-related death. In conclusion, the risk of developing DPM in DTC patients was elevated in older, male patients with an advanced tumor-node-metastasis stage. DPM adversely affected the OS of thyroid cancer patients. Male gender, two or more DPMs, and shorter time interval between occurrences were significant risk factors for OS in DPM patients.

Familial Aggregation and Heritability of Nonmedullary Thyroid Cancer in an Asian Population: A Nationwide Cohort Study

PURPOSE

The purpose of this work is to assess the extent of familial aggregation of nonmedullary thyroid cancer (NMTC) and the relative risks (RRs) of chronic thyroid diseases and common malignancies in first-degree relatives of NMTC patients.

METHODS

In the National Health Insurance Research database of Taiwan, all eligible individuals in 2016 were analyzed (n = 23 696 659) and the family structures of 38 686 patients diagnosed with NMTC between 1997 and 2016 were identified. The prevalence and RRs of NMTC, chronic thyroid diseases, and common malignancies in individuals with first-degree relatives with NMTC were examined. The accountability of heritability and environmental factors to NMTC susceptibility was estimated using the polygenic liability model.

RESULTS

The prevalence of NMTC was 0.16% in the general population and 0.64% in individuals with first-degree relatives with NMTC. Regarding affected relatives, the RR (95% CI) for NMTC was 20.12 (4.86-83.29) for twins, 6.43 (4.80-8.62) for siblings, 5.24 (4.55-6.03) for offspring, 5.07 (4.41-5.81) for parents, and 2.07 (1.53-2.81) for spouses. The estimated genetic, common environmental, and nonshared environmental contributions to NMTC were 28.0%, 14.3%, and 57.7%, respectively. A family history of NMTC was associated with higher risks of thyroid nodules (RR, 2.26; 95% CI, 2.18-2.35), Hashimoto thyroiditis (2.11; 1.89-2.36), Graves disease (1.49; 1.42-1.57), lung cancer (1.56; 1.32-1.85), and leukemia and lymphoma (1.24; 1.03-1.50).

CONCLUSION

Our findings demonstrate the importance of genetic and environmental contributions to NMTC susceptibility and highlight the coaggregation of chronic thyroid diseases and multiple malignancies with NMTC.

Long-term survival among patients with gastrointestinal stromal tumors diagnosed after another malignancy: a SEER population-based study

Background

To explore overall survival (OS) and GISTs-specific survival (GSS) among cancer survivors developing a second primary gastrointestinal stromal tumors (GISTs).

Methods

We conducted a cohort study, where patients with GISTs after another malignancy (AM-GISTs, n = 851) and those with only GISTs (GISTs-1, n = 7660) were identified from the Surveillance, Epidemiology, and End Results registries (1988–2016). Clinicopathologic characteristics and survival were compared between the two groups.

Results

The most commonly diagnosed first primary malignancy was prostate cancer (27.7%), followed by breast cancer (16.2%). OS among AM-GISTs was significantly inferior to that of GISTs-1; 10-year OS was 40.3% vs. 50.0%, (p < 0.001). A contrary finding was observed for GSS (10-year GSS 68.9% vs. 61.8%, p = 0.002). In the AM-GISTs group, a total of 338 patients died, of which 26.0% died of their initial cancer and 40.8% died of GISTs. Independent of demographics and clinicopathological characteristics, mortality from GISTs among AM-GISTs patients was decreased compared with their GISTs-1 counterparts (HR, 0.71; 95% CI, 0.59–0.84; p < 0.001), whereas OS was inferior among AM-GISTs (HR, 1.11; 95% CI, 0.99–1.25; p = 0.085).

Conclusions

AM-GISTs patients have decreased risk of dying from GISTs compared with GIST-1. Although another malignancy history does not seemingly affect OS for GISTs patients, clinical treatment of such patients should be cautious.

Risk of breast cancer-related death in women with a prior cancer

The overall risk of developing a second primary cancer is increasing. The purpose of this study was to analyze the survival of patients with breast cancer diagnosed after a prior cancer and identify risk factors of breast cancer death in this population. Using the SEER database, we identified 1,310 woman diagnosed with breast cancer between 2010 and 2015 after a prior cancer as the primary cohort. Clinicopathological characteristics were compared using the Student t-test and chi-square test. Fine and Gray’s regression was used to evaluate the effect of treatments on breast cancer death. After propensity score matching (PSM), 9,845 pairs of patients with breast cancer as the prior or second cancer diagnosed between 2010 and 2011 were included as a second cohort. PSM-adjusted Kaplan-Meier and Cox hazards models were used to evaluate the impact of prior cancer on survival. The results showed that survivors of gynecologic cancers (e.g., ovarian cancer) had a higher risk of developing breast cancer than survivors of gastrointestinal and urinary tract cancers. More patients died of breast cancer than of prior urinary cancer (53.3% vs. 40%, P < 0.05) and melanoma (66.7% vs. 33.3%, P < 0.05). The ratio of breast cancer deaths to prior cancer deaths was significantly higher in patients with diagnoses interval ≥ 3 years than in those with the interval < 3 years (2.67 vs. 0.69, P < 0.001). Breast cancer-specific survival and overall survival rates were significantly lower in women with breast cancer as the second primary cancer than in those with breast cancer as the prior cancer, especially among hormone receptor-positive women. However, breast cancer treatment decreased the risk of breast cancer -specific death (hazard ratio = 0.695, 95% confidence interval: 0.586–0.725, P < 0.001). Breast cancer patients with prior cancers must be carefully considered for clinical trials.

Breast Cancer After Treatment of Differentiated Thyroid Cancer With Radioiodine in Young Females: What We Know and How to Investigate Open Questions. Review of the Literature and Results of a Multi-Registry Survey

Published studies on the risk of radiation-induced second primary malignancy (SPM) after radioiodine treatment (RAI) of differentiated thyroid cancer (DTC) refer mainly to patients treated as middle-aged or older adults and are not easily generalizable to those treated at a younger age. Here we review available literature on the risk of breast cancer as an SPM after RAI of DTC with a focus on females undergoing such treatment in childhood, adolescence, or young adulthood. Additionally, we report the results of a preliminary international survey of patient registries from academic tertiary referral centers specializing in pediatric DTC. The survey sought to evaluate the availability of sufficient patient data for a potential international multicenter observational case-control study of females with DTC given RAI at an early age. Our literature review identified a bi-directional association of DTC and breast cancer. The general breast cancer risk in adult DTC survivors is low, ~2%, slightly higher in females than in males, but presumably lower, not higher, in those diagnosed as children or adolescents than in those diagnosed at older ages. RAI presumably does not substantially influence breast cancer risk after DTC. However, data from patients given RAI at young ages are sparse and insufficient to make definitive conclusions regarding age dependence of the risk of breast cancer as a SPM after RAI of DTC. The preliminary analysis of data from 10 thyroid cancer registries worldwide, including altogether 6,449 patients given RAI for DTC and 1,116 controls, i.e., patients not given RAI, did not show a significant increase of breast cancer incidence after RAI. However, the numbers of cases and controls were insufficient to draw statistically reliable conclusions, and the proportion of those receiving RAI at the earliest ages was too low.In conclusion, a potential international multicenter study of female patients undergoing RAI of DTC as children, adolescents, or young adults, with a sufficient sample size, is feasible. However, breast cancer screening of a larger cohort of DTC patients is not unproblematic for ethical reasons, due to the likely, at most slightly, increased risk of breast cancer post-RAI and the expected ~10% false-positivity rate which potentially produced substantial "misdiagnosis."

Radioactive Iodine-Related Clonal Hematopoiesis in Thyroid Cancer Is Common and Associated With Decreased Survival

CONTEXT

Radioactive iodine (RAI) has been epidemiologically associated with the development of hematologic malignancies. Clonal hematopoiesis (CH) is a precursor clonal state that confers increased risk of leukemia and occurs at an elevated rate in patients with thyroid cancer relative to other solid tumors.

OBJECTIVE

We explore if the high prevalence of CH may be a result of RAI exposure and whether CH may be a surrogate in the association between RAI and leukemia.

DESIGN

CH, CH-potential driver (CH-PD), and overall survival were evaluated in 279 patients with advanced thyroid carcinoma.

RESULTS

The prevalence of CH in patients with thyroid cancer was 37%, and that of CH-PD was 5.2%. Age was the strongest predictor of CH and CH-PD. For every year increase in age, there was a 5% and 13% increase in the odds of CH and CH-PD, respectively. RAI dose was significantly associated with CH and CH-PD, even after adjustment for age, external beam radiation therapy, and chemotherapy. For every 10 mCi increase in the dose of RAI administered, there was a 2% and 4% increase in the odds of CH and CH-PD, respectively. Patients with CH-PD previously exposed to RAI had a significantly poorer survival, even when stratified by age (heart rate = 3.75, 95% CI = 1.23 to 11.5, P = 0.02).

CONCLUSIONS

RAI was associated with a high prevalence of CH, and CH is a precursor state of hematologic malignancies. The implications of this study may favor identification of CH in patients where the risks might outweigh the benefits of receiving RAI therapy for thyroid cancer.

Excessive risk of second primary cancers in young-onset colorectal cancer survivors

With an increasing trend of patients with young-onset colorectal cancer (CRC), risks of second primary cancers (SPCs) among them become a concerning issue. We aimed to define the detailed risk and site-distributed patterns of SPCs in young CRC individuals (age ≤50). A population-based cohort were identified from the Surveillance, Epidemiology, and End Results database between 1973 and 2013. Standardized incidence ratios (SIRs) and absolute excess risk (AER) were calculated to assess the risk for SPCs compared with the general population. A total of 44,106 patients, including 3245 (7.4%) the young and 40,861 (92.6%) the old, developed 50,679 secondary malignancies subsequently. With increased age, the risk of secondary cancers gradually decreased. A significant 44% excess risk of SPCs was observed in the young (SIR = 1.44, AER = 34.23), while a slightly increased risk was noted in the old (SIR = 1.02, AER = 4.29). For young survivors, the small intestine (SIR = 8.49), bile ducts (SIR = 3.77), corpus, and uterus (SIR = 2.45) were the most common sites of SPCs. Significantly, excess SIRs in the young were persisted regardless of other factors. For the young, secondary cancer-related deaths were responsible for 51.2% of overall deaths and secondary stomach, liver and bile, pancreas cancers were top three causes. An excessive risk of SPCs existed in young CRC survivors, and this trend was consistent among different subgroups. We hope our findings may inform future targeted screening strategies among young-onset CRC survivors.

Myeloid Neoplasia and Lymphoblastic Lymphoma with Eosinophilia After Radioactive Iodine: A Case Report

BACKGROUND

Thyroid cancer is the most common endocrine cancer, with an increasing incidence around the world in the last three decades. The increased risk of secondary cancer is associated with a genetic predisposition or radioactive iodine used in the treatment.

CASE REPORT

A 65-year old male patient was operated on for thyroid papillary cancer. He received radioactive iodine on two occasions postoperatively. After six years, he presented with malaise and fatigue with leukocytosis and eosinophlilia. The physical examination revealed inguinal lymphadenopathies and splenomegaly, after examining the bone marrow and lymph node biopsies, he was diagnosed with eosinophilic myeloproliferative neoplasia and T-cell lymphoblastic leukaemia/lymphoma.

CONCLUSION

Leukaemia and other haematological malignencies may develop after radioactive iodine treatment. Patients with radioactive iodine ablation history should be monitored for a long time.

Long term outcomes of simple clinical risk stratification in management of differentiated thyroid cancer

OBJECTIVE

To establish the long term outcomes of risk stratified management of differentiated thyroid cancer (DTC).

BACKGROUND

Guidelines for management of DTC lack a strong evidence base and expose patients to overtreatment. This prospective study of patients diagnosed with DTC between 1977 and 2012 describes the long term outcomes of a conservative risk stratified (AMES) management policy.

METHODS

Outcomes were analysed around patient and tumour characteristics, primary intervention (surgery ± radioiodine (RAI)), in terms of mortality, recurrence and reintervention.

RESULTS

Median follow-up in 348 patients was 14 years: mean age 48 (range 10-91) years, 257 (73.9%) female, 222 (68.3%) papillary cancer, tumour size 3.4 ± 2.0 cm (mean ± SD). 89 (25.6%) AMES high risk, 116 (33.3%) TNM stage III/IV and 16 (4.6%) had distant metastases. Primary surgery comprised lobectomy in 189 (54.3%): 11 (5.8%) patients had subsequent completion total thyroidectomy with cancer present in five. Primary nodal surgery was performed in 142 (40.8%) patients. 35 (13.5%) low and 43 (48.3%) high risk patients received RAI following initial surgery. Overall disease specific survival (DSS) was 92.1% at 10 years and 90.7% at 20 years. DSS at 20 years was 99.2% in low risk cases. AMES risk scoring predicted both survival and recurrence. Patients receiving RAI and AMES high risk were significantly associated with increased risk of death and recurrence.

CONCLUSIONS

Routine total thyroidectomy and RAI are not justifiable for low risk DTC. Treatment should be tailored to risk and AMES risk stratification remains a simple reliable clinical tool.

Risk of Hematologic Malignancies After Radioiodine Treatment of Well-Differentiated Thyroid Cancer

Purpose To investigate the risk and outcomes of second hematologic malignancies (SHMs) in a population-based cohort of patients with well-differentiated thyroid cancer (WDTC) treated or not with radioactive iodine (RAI). Methods Patients with WDTC were identified from SEER registries. Competing risk regression analysis was performed to calculate the risks of SHMs that occurred after WDTC treatment and outcomes after SHM development were assessed. Results Of 148,215 patients with WDTC, 53% received surgery alone and 47% received RAI. In total, 783 patients developed an SHM after a median interval of 6.5 years (interquartile range, 3.3 to 11.2 years) from WDTC diagnosis. In multivariable analysis, compared with those undergoing thyroidectomy alone, RAI treatment was associated with an increased early risk of developing acute myeloid leukemia (AML; hazard ratio, 1.79; 95% CI, 1.13 to 2.82; P = .01) and chronic myeloid leukemia (CML; hazard ratio, 3.44; 95% CI, 1.87 to 6.36; P < .001). This increased risk of AML and CML after RAI treatment was seen even in low-risk and intermediate-risk WDTC tumors. Occurrence of AML but not CML in patients with WDTC was associated with shorter median overall survival compared with matched controls (8.0 years v 31.0 years; P = .001). In addition, AML developing after RAI trended toward inferior survival compared with matched controls with de novo AML (median overall survival, 1.2 years v 2.9 years; P = .06). Conclusion Patients with WDTC treated with RAI had an increased early risk of developing AML and CML but no other hematologic malignancies. AML that arises after RAI treatment has a poor prognosis. RAI use in patients with WDTC should be limited to patients with high-risk disease features, and patients with WDTC treated with adjuvant RAI should be monitored for myeloid malignancies as part of cancer surveillance.

Trends of Second Primary Malignancy in Patients with Thyroid Cancer: A Population-Based Cohort Study in Israel

BACKGROUND

Thyroid cancer (TC) is the most common endocrine malignancy. TC patients have a good prognosis and a low disease-related mortality rate. Since such patients are often young, they may be at a higher risk for a second primary malignancy (SPM). This study sought to determine the incidence, risk, and types of SPM between 1980 and 2011, and to assess SPM trends over time among Israeli TC patients.

METHODS

Data were derived from the Israel National Cancer Registry. Primary TC patients diagnosed during 1980-2009 were followed up for SPM incidence until December 31, 2011. Standardized incidence ratios (SIRs) of observed to expected SPM (based on the general population rates) were calculated using Poisson regression. Analyses were stratified by time period of initial TC diagnosis (1980-1995 and 1996-2009).

RESULTS

A total of 11,538 TC patients were identified. After exclusion of 107 duplicate cases, records of 1032 patients with SPM were analyzed (an SPM incidence of 8.9%). SIRs for all-site SPMs were 1.23 [confidence interval 1.08-1.35] for males and 1.19 [confidence interval 1.10-1.27] for females. SIRs for tumors of the urinary system and prostate were significantly elevated in males, as were SIRs for tumors of the brain, urinary system, breast, and lung in females. Variables associated with increased risk of developing SPMs included a younger age at TC diagnosis, a shorter latency period, being born in Asia/Africa for both sexes, and being born in Israel for females. Compared with the general population, a subanalysis by TC diagnosis during 1980-1995 and 1996-2009 disclosed a higher SPM incidence for the latter time period in males and for both time periods, with a slightly higher SIR for the latter time period in females.

CONCLUSIONS

The overall risk of SPM in Israeli TC patients was significantly greater for both sexes compared with the general population, thus identifying TC patients as a high-risk group and calling for caretakers to apply specific follow-up guidelines.

Association between thyroid cancer and epidermal growth factor receptor mutation in female with nonsmall cell lung cancer

BACKGROUND

The aim of this study was to investigate the association between epidermal growth factor receptor (EGFR) mutation and thyroid cancer in female patients with nonsmall-cell lung cancer (NSCLC).

METHODS

In a retrospective study, we examined 835 female patients who were diagnosed with NSCLC and underwent an EGFR mutation test between June 2003 and August 2013. The associations of EGFR mutation with thyroid cancer and a family history of thyroid cancer were evaluated using logistic regression models.

RESULTS

EGFR mutation was found in 378 of 835 patients. In addition to adenocarcinoma (P < 0.001), EGFR mutations were positively associated with a personal history of thyroid cancer (5.8% versus 2.6%; P = 0.020), while showing a trend toward inverse association with a personal history of nonthyroid cancer (5.8% vs. 9.0%; P = 0.086). Likewise, the incidence of EGFR mutations was associated with a family history of thyroid cancer (2.9% vs. 0.9%; P = 0.028), while showing a trend toward inverse association with a family history of nonthyroid cancer (27.8% vs. 33.7%; P = 0.066). Multivariate logistic regression showed that the incidence of EGFR mutations was different in women with thyroid or nonthyroid cancer (P = 0.035) and in women with a family history of thyroid or nonthyroid cancer (P = 0.023).

CONCLUSIONS

Our data suggest that thyroid cancer and a family history of thyroid cancer are associated with EGFR-mutated NSCLC in female patients. The differences in the incidence of thyroid cancer and a family history of thyroid cancer by EGFR mutational status provide new insight into pathogenesis of this genetic change.

The Breast-Thyroid Cancer Link: A Systematic Review and Meta-analysis

Rates of thyroid cancer in women with a history of breast cancer are higher than expected. Similarly, rates of breast cancer in those with a history of thyroid cancer are increased. Explanations for these associations include detection bias, shared hormonal risk factors, treatment effect, and genetic susceptibility. With increasing numbers of breast and thyroid cancer survivors, clinicians should be particularly cognizant of this association. Here, we perform a systematic review and meta-analysis of the literature utilizing PubMed and Scopus search engines to identify all publications studying the incidence of breast cancer as a secondary malignancy following a diagnosis of thyroid cancer or thyroid cancer following a diagnosis of breast cancer. This demonstrated an increased risk of thyroid cancer as a secondary malignancy following breast cancer [OR = 1.55; 95% confidence interval (CI), 1.44-1.67] and an increased risk of breast cancer as a secondary malignancy following thyroid cancer (OR = 1.18; 95% CI, 1.09-1.26). There is a clear increase in the odds of developing either thyroid or breast cancer as a secondary malignancy after diagnosis with the other. Here, we review this association and current hypothesis as to the cause of this correlation.

Risk of second primary malignancies among cancer survivors in the United States, 1992 through 2008

BACKGROUND

In the current study, the authors attempted to describe the incidence, most common sites, and mortality of second primary malignancies among survivors of common cancers.

METHODS

The authors identified patients aged ≥18 years who were diagnosed with a primary malignancy from the 10 most common cancer sites (prostate, breast, lung, colon, rectum, bladder, uterus, kidney, melanoma, and non-Hodgkin lymphoma) between 1992 and 2008 from Surveillance, Epidemiology, and End Results data. Factors associated with the incidence of second primary malignancies were explored using bivariable and multivariable models, and mortality attributable to first and second primary malignancies was examined.

RESULTS

A cohort of 2,116,163 patients was identified, 170,865 of whom (8.1%) developed a second primary malignancy. Survivors of bladder cancer had the highest risk of developing a second cancer. In a multivariable model controlling for age, race, tumor grade, stage of disease, marital status, educational level, and income, a history of non-Hodgkin lymphoma (hazard ratios of 2.70 and 2.88, respectively, for men and women) and bladder cancer (hazard ratios of 1.88 and 1.66, respectively, for men and women) predicted the highest risk of developing a second cancer. For patients with 2 incident cancers, 13% died of their initial cancer, but greater than one-half (55%) died of their second primary malignancy. Lung cancer was the cause of death in 12% of patients with 2 incident cancers.

CONCLUSIONS

Nearly 1 in 12 patients diagnosed with a common cancer developed a second malignancy, the most common of which was lung cancer. Greater than one-half of patients with 2 incident cancers died of their secondary malignancy. The findings from the current study may inform care strategies among cancer survivors. Cancer 2016;122:3075-3086. © 2016 American Cancer Society.

Survival impact of locoregional metachronous malignancy in survival of lung cancer patients who received curative treatment

BACKGROUND

Metachronous malignancy is also found in the lung cancer population and may be identified before or after diagnosis of lung cancer. No prior studies have documented lung cancer patients with metachronous malignancy and its survival impact in this population. The aim of this study was to try to clarify the survival impact of locoregional metachronous malignancy in the lung cancer population with resectable disease from a pathology point of view.

METHODS

From January 2005 to December 2009, 199 lung cancer patients received curative treatment in Chang Gung Memorial Hospital, of which 34 were identified as having lung cancer and metachronous malignancy and 165 patients as having lung cancer only. Clinico-pathologic factors were collected from the medical records. Differences in clinical presentations between the two groups and survival impact were further analyzed.

RESULTS

Of these patients, 165 patients (82.9%) had lung cancer only (lung cancer group), and the remaining 34 patients (17.1%) had lung cancer and metachronous malignancy (metachronous malignancy group). There were no significant differences in clinical characteristics between the two groups. The disease free survival (P=0.3199) and overall survival (P=0.71) between these two groups showed no statistically significant difference. Metachronous malignancy only showed survival impact in lung cancer patients with pathologic stage IIIA (P=0.0389).

CONCLUSIONS

Metachronous malignancy is also seen in the lung cancer population and may be identified before or after diagnosis of lung cancer. Locoregional metachronous malignancy has no survival impact on lung cancer patients who receive curative treatment. Anatomic resection with regional lymph node (LN) dissection is recommended if different tumor cell type and resectable disease are confirmed.

THYROID MALIGNANCY RISK OF INCIDENTAL THYROID NODULES IN PATIENTS WITH NON-THYROID CANCER

Context

Thyroid incidentaloma is a common disorder in endocrinology practice. Current literature regarding the risk of thyroid cancer in incidentalomas found in patients with non-thyroid cancer is limited.

Objective

The aim of the present study was to investigate the frequency of thyroid malignancy in thyroid incidentalomas detected in patients with non-thyroid cancer.

Design

Case control study.

Subjects and Methods

The database of 287 thyroid nodules from 161 patients with a history of non-thyroid cancer followed between 2008 and 2014 were retrospectively evaluated.

Results

From 287 thyroid nodules, 69.7 % had a benign final cytology. Thyroid cancer detected in one nodule while follicular neoplasia detected in 4 nodules, atypia of unknown significance (AUS) detected in 10 nodules, Hurthle cell neoplasia detected in 5 nodules and suspicious for malignancy detected in 6 nodules according to fine needle aspiration biopsy results. Metastasis of the non-thyroid cancer to the thyroid gland was detected in 4 nodules. Twenty seven nodules from 15 patients were removed with surgery. There were 3 malignant nodules found after surgery (1 papillary, 1 follicular and 1 medullary cancer). In addition to these three thyroid cancers, two patients with benign nodules had co-incidental thyroid cancer detected after surgery. Finally, 11.1 % of thyroid nodules which underwent thyroid surgery had malignant histopathology except for co-incidental and metastatic cancers.

Conclusions

The frequency of thyroid malignancy seems not to be substantially increased in incidental thyroid nodules detected in patients with non-thyroid cancer when these patients were evaluated in nodule-based approach.

Targeted DNA Sequencing Detects Mutations Related to Susceptibility among Familial Non-medullary Thyroid Cancer

Some studies have demonstrated that familial non-medullary thyroid cancer (FNMTC) has a more aggressive clinical behavior compared to sporadic NMTC (SNMTC). However, FNMTC is difficult to differentiate from SNMTC by the morphology and immunohistochemistry. Although genes responsible for FNMTC were unclear, screening for rare germline mutations on known important tumor suppressor genes might offer more insights on predicting susceptibility to FNMTC. Here, a customized panel was designed to capture all exons of 31 cancer susceptive genes possibly related to FNMTC. Using next-generation sequencing we performed deep sequencing to achieve 500× coverage of the targeted regions. At the end 45 variants were identified in 29 of 47 familial patients and 6 of 16 sporadic patients. Notably, several germline mutations were found matching between paired FNMTC patients from the same family, including APC L292F and A2778S, BRAF D22N, MSH6 G355S and A36V, MSH2 L719F, MEN1 G508D, BRCA1 SS955S, BRCA2 G2508S, and a GNAS inframe insertion. We demonstrated a novel approach to help diagnose and elucidate the genetic cause of the FNMTC patients, and assess whether their family members are exposed to a higher genetic risk. The findings would also provide insights on monitoring the potential second cancers for thyroid cancer patients.

The association between breast cancer and thyroid cancer: a meta-analysis

Previous studies have suggested an association between breast cancer and thyroid cancer; however, there has not been a formal meta-analysis which collates the existing evidence supporting the hypothesis that breast cancer or thyroid cancer predisposes an individual to developing the other. A systematic search was carried out using PubMed and Medline. We searched for articles containing epidemiological evidence of breast cancer following thyroid cancer and vice versa. Additionally, we searched for articles that included epidemiological data involving the incidence of all second primary malignancies (SPMs) following both breast cancer and thyroid cancer, and compared the datasets. The meta-analysis performed in a total of 18 studies showed that there is a significantly increased risk of developing thyroid cancer as a second primary malignancy of breast cancer (SIR = 1.59, 95 % confidence interval (CI) 1.28-1.99). Additionally, there was marginally increased risk of developing breast cancer as a second primary malignancy of thyroid cancer (SIR = 1.24, 95 % CI 1.16-1.33), compared to the general risk of developing a second primary malignancy following thyroid cancer. The findings suggest that the risk of developing thyroid cancer as a second primary malignancy of breast cancer and vice versa is increased compared to the background risk of developing other SPMs. The risk of developing thyroid cancer after a primary breast cancer was higher than the risk of developing breast cancer as a second primary malignancy of thyroid cancer. This suggests that the effects of treatment-related factors and specific pathological processes of each cancer may contribute to the increased risk rather than common risk factors including genetic factors. Elucidation of the common mechanisms between breast cancer and thyroid cancer will have important implications in both diagnostic and therapeutic management of these cancers. Benefit of thyroid ultrasound screening after breast cancer surgery needs to be assessed.

The impact of locoregional recurrences and distant metastases on the survival of patients with papillary thyroid carcinoma

OBJECTIVE

Some patients with papillary thyroid carcinoma (PTC) would suffer from locoregional recurrences or distant metastases. This study was aimed to elucidate the impacts of locoregional recurrences and distant metastases on these patients' survival.

DESIGN

Retrospective hospital-based cohort study.

POPULATION

Data were collected from 1636 subjects with PTC at National Taiwan University Hospital between 1985 and 2007.

MEASUREMENTS

Overall and disease-specific survival curves were estimated by the Kaplan-Meier method. Time-independent and time-dependent prognostic factors were included simultaneously in multivariate analyses using Cox models.

RESULTS

Overall survival (OS) rates at 10- and 20-years were 90% and 76%, respectively. The 10- and 20-year disease-specific survival (DSS) rates were 95% and 90%, respectively. Our multivariate analyses identified that older age, distant metastases (hazard ratio, HR: 6·69, 95% CI: 4·40-10·18), locoregional recurrences (HR: 1·88, 95% CI: 1·22-2·89), lymph node metastases, massive extrathyroid extension, male gender and larger tumour size (>4 cm) were significantly associated with poorer OS. Older age, distant metastases (HR: 15·03, 95% CI: 8·31-27·21), locoregional recurrences (HR: 3·63, 95% CI: 2·03-6·51), massive extrathyroid extension, male gender and larger tumour size (>4 cm) were independently related to worse DSS. The performance of high-dose (131) I ablation had a protective effect on OS and DSS.

CONCLUSION

The locoregional recurrences had a moderately harmful impact on OS and DSS, but age and distant metastases were the major decisive factors for OS and DSS. High-dose (131) I ablation had a protective role. However, lymph node dissection did not alter the prognosis whenever lymph node metastases only influenced OS.

Co-occurrence of second primary malignancy in patients with thyroid cancer

BACKGROUND

The discovery of asynchronous or synchronous double or multiple malignancies in patients is not uncommon. The co-occurrence of second primary malignancy (SPM) could be randomly occurring or association with risk factors such as environmental, genetic predisposition and therapy-related.

MATERIALS AND METHODS

We retrieved ∼782 million claim records consisting of 10.8 million males and 10.6 million females from Taiwan's National Health Insurance, which were collected for a period of 3 years (January 2000-December 2002). All the patient records were stratified by gender and ages at a 20-year interval with SPMs and specific groups. Interestingness or Q-value was used to measure strength of the disease-disease associations.

RESULTS

A total of 9423 thyroid cancer (female: 7483, male: 1940), 276 184 SPM (female: 141 023, male: 135 161) and 861 co-occurrence cases (female: 583, male: 278) were recorded. The co-occurrence incidence rate of head and neck, breast, digestive system and lung was 1.93%, 1.59%, 1.44% and 1.18%, respectively. Malignancy of salivary glands, laryngx, sarcoma, lymphoid tissue, mouth, central nervous system and lungs found Q-value >10. Malignancies with intermediate Q-values (5.0-9.9) were observed in nasopharynx, kidney and ureter, breast, stomach and skin. Prostate, leukemia, urinary bladder, ovary, colon, liver and uterine cervix cancer have lower Q-values (1.0-4.9).

CONCLUSION

Co-occurrence ratio of thyroid cancer and SPM was high, occurred in all organ systems. We postulated that the aggressive use of modern diagnostic modalities, aggressive radioiodine treatment, pre-existing molecular oncogen mutations, and thyroid hormone for simultaneously supple-mentary and suppressive therapies were responsible.