Thyroid cancer overdiagnosis revisited

Exosomal noncoding RNAs: decoding their role in thyroid cancer progression

Exosomes, as pivotal entities within the tumor microenvironment, orchestrate intercellular communication through the transfer of diverse molecules, among which non-coding RNAs (ncRNAs) such as miRNAs, lncRNAs, and circRNAs play a crucial role. These ncRNAs, endowed with regulatory functions, are selectively incorporated into exosomes. Emerging evidence underscores the significance of exosomal ncRNAs in modulating key oncogenic processes in thyroid cancer (TC), including proliferation, metastasis, epithelial-mesenchymal transition (EMT), angiogenesis, and immunoediting. The unique composition of exosomes shields their cargo from enzymatic and chemical degradation, ensuring their integrity and facilitating their specific expression in plasma. This positions exosomal ncRNAs as promising candidates for novel diagnostic and prognostic biomarkers in TC. Moreover, the potential of exosomes in the therapeutic landscape of TC is increasingly recognized. This review aims to elucidate the intricate relationship between exosomal ncRNAs and TC, fostering a deeper comprehension of their mechanistic involvement. By doing so, it endeavors to propel forward the exploration of exosomal ncRNAs in TC, ultimately paving the way for innovative diagnostic and therapeutic strategies predicated on exosomes and their ncRNA content.

The Use of Tissue-on-Chip Technology to Focus the Search for Extracellular Vesicle miRNA Biomarkers in Thyroid Disease

Small extracellular vesicles (sEVs) contain microRNAs (miRNAs) which have potential to act as disease-specific biomarkers. The current study uses an established method to maintain human thyroid tissue ex vivo on a tissue-on-chip device, allowing the collection, isolation and interrogation of the sEVs released directly from thyroid tissue. sEVs were analysed for differences in miRNA levels released from benign thyroid tissue, Graves' disease tissue and papillary thyroid cancer (PTC), using miRNA sequencing and quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) to identify potential biomarkers of disease. Thyroid biopsies from patients with benign tissue (n = 5), Graves' disease (n = 5) and PTC (n = 5) were perfused with medium containing sEV-depleted serum for 6 days on the tissue-on-chip device. During incubation, the effluents were collected and ultracentrifuged to isolate sEVs; miRNA was extracted and sequenced (miRNASeq). Out of the 15 samples, 14 passed the quality control and miRNASeq analysis detected significantly higher expression of miR-375-3p, miR-7-5p, miR-382-5p and miR-127-3p in the sEVs isolated from Graves' tissue compared to those from benign tissue (false discovery rate; FDR p < 0.05). Similarly, miR-375-3p and miR-7-5p were also detected at a higher level in the Graves' tissue sEVs compared to the PTC tissue sEVs (FDR p < 0.05). No significant differences were observed between miRNA in sEVs from PTC vs. those from benign tissue. These results were supported by Quantitative Reverse Transcriptase Polymerase Chain Reaction (qRT-PCR). The novel findings demonstrate that the tissue-on-chip technology is a robust method for isolating sEVs directly from the tissue of interest, which has permitted the identification of four miRNAs, with which further investigation could be used as biomarkers or therapeutic targets within thyroid disease.

Drivers of Thyroid Ultrasound Use: A Retrospective Observational Study

OBJECTIVE

Excessive use of thyroid ultrasound (TUS) contributes to the overdiagnosis of thyroid nodules and thyroid cancer. In this study, we evaluated drivers of and clinical trajectories following TUS orders.

METHODS

We conducted a retrospective review of 500 adult patients who underwent an initial TUS between 2015 and 2017 at Mayo Clinic in Rochester, MN. A framework was employed to classify the indication for TUS, and it was characterized as inappropriate when ordered without a guideline-based indication. Medical records were reviewed for up to 12 months following the TUS, and clinical outcomes were evaluated.

RESULTS

The mean age mean age (SD) was 53.6 years (16.6), 63.8% female, and 86.6% white. TUS orders were triggered by incidental findings on unrelated imaging (31.6%), thyroid symptoms (20.4%), thyroid abnormalities on routine physical examination (17.2%), and thyroid dysfunction workup (11.8%). In females and males, the most common reason were incidental findings on imaging (female, 91/319, 28.5% and male, 67/181, 37.0%). In primary care practice, TUS orders were mostly triggered by symptoms (71/218, 32.5%), while thyroid dysfunction workup was the primary reason in endocrinology (28/100, 28.0%). We classified 11.2% (56/500) TUS orders as likely to have been ordered inappropriately based on current guidelines. Finally, 119 patients (119/500, 23.8%) had a thyroid biopsy with 11.8% had thyroid cancer (14/119. 11.8%).

CONCLUSIONS

Incidental findings on imaging, symptoms, and routine physical exam findings in asymptomatic patients were the most prevalent drivers of TUS. Furthermore, 1 in 10 TUS were likely inappropriately ordered based on current practice guidelines.

Overuse of thyroid ultrasound

PURPOSE OF REVIEW

Thyroid ultrasound (TUS) is a common diagnostic test that can help guide the management of patients with thyroid conditions. Yet, inappropriate use of TUS can lead to harmful unintended consequences. This review aims to describe trends in the use and appropriateness of TUS in practice, drivers and consequences of inappropriate use, and potential solutions to decrease overuse.

RECENT FINDINGS

TUS use has increased in the U.S. and is associated with increased diagnosis of thyroid cancer. Between 10-50% of TUSs may be ordered outside of clinical practice recommendations. Patients who receive an inappropriate TUS and are incidentally found to have a thyroid nodule may experience unnecessary worry, diagnostic interventions, and potential overdiagnosis of thyroid cancer. The drivers of inappropriate TUS use are not yet fully understood, but it is likely that a combination of clinician, patient, and healthcare system factors contribute to this problem.

SUMMARY

Inappropriate TUS is a factor leading to the overdiagnosis of thyroid nodules and thyroid cancer, resulting in increased healthcare costs and potential harm to patients. To effectively address the overuse of this diagnostic test, it is necessary to gain a deeper understanding of the frequency of inappropriate TUS use in clinical practice and the factors that contribute to it. With this knowledge, interventions can be developed to reduce the inappropriate use of TUS, leading to improved patient outcomes and more efficient use of healthcare resources.

Per- and Polyfluoroalkyl Substances (PFAS) in Community Water Systems (CWS) and the Risk of Thyroid Cancer: An Ecological Study

Thyroid cancer incidence has been steadily increasing over the past decade in the United States (US). A discussion exists regarding the potential contribution of exposure to endocrine-disrupting chemicals, encompassing certain per- and poly-fluoroalkyl substances (PFASs). This ecological study evaluated the potential correlation between PFAS levels in drinking water and thyroid cancer incidence in the US. Data on age-adjusted thyroid cancer incidence rate (per 100,000 persons) by county were obtained from the Centers for Disease Control and Prevention (CDC) for US counties with available data in 2015-2019. Data on PFAS concentrations in the drinking water of selected community water systems (CWSs) were obtained from the CDC National Environmental Public Health Tracking Network in 2013-2015. The correlation between PFASs in CWSs and thyroid cancer incidence was calculated using Spearman correlation. A statistically significant correlation was found between perfluorooctanoic acid (PFOA) (r = 0.031; p = 0.043), perfluorononanoic acid (PFNA) (r = 0.058; p ≤ 0.001), and thyroid cancer incidence. The results suggest a potential link between certain PFAS exposures and thyroid cancer risk. However, due to the nature of an ecological study, no conclusions can be drawn at the individual level or causality. More research is needed, particularly on an individual level to allow for more detailed exposure assessment.

Upregulation and the clinical significance of KCNQ1OT1 and HAGLROS lncRNAs in papillary thyroid cancer: An observational study

Long noncoding RNAs (lncRNAs) play an important role in regulating gene expression. Changes in their expression have been associated with many types of cancer, including thyroid cancer. This study aimed to investigate how changes in the expression of potassium voltage-gated channel subfamily Q member 1 opposite strand/antisense transcript 1 (KCNQ1OT1) and HAGLR opposite strand lncRNA (HAGLROS) lncRNAs correlate with the development and clinicopathological characteristics of papillary thyroid cancer (PTC). Reverse transcription-quantitative polymerase chain reaction was used to investigate the expression of lncRNAs in both tumor and adjacent normal thyroid tissue samples of the patients. Expressions of KCNQ1OT1 and HAGLROS were upregulated in the patients tumor samples compared to the adjacent normal thyroid samples. KCNQ1OT1 expression was linked to microcarcinoma and gender, while HAGLROS expression was linked to microcarcinoma and tumor size. When only microcarcinoma samples were evaluated, KCNQ1OT1 expression was higher in tumor tissues compared to normal tissues; however, no significant difference was observed in HAGLROS expression. Our data suggests that high expressions of KCNQ1OT1 and HAGLROS might contribute to the development of PTC and disease progression, and both lncRNAs may be potential therapeutic targets in PTC patients.

[Hemithyroidectomy or total thyroidectomy for low-risk papillary thyroid cancer? : Surgical criteria for primary and secondary choice of treatment in an interdisciplinary treatment concept]

The increase in small intrathyroid papillary thyroid cancer (PTC) observed worldwide over the past two decades, with no increase in cancer-specific mortality, has challenged the previous concept of total thyroidectomy as a one-size-fits-all panacea. After exclusion of papillary microcarcinomas, a systematic review of 20 clinical studies published since 2002, which compared hemithyroidectomy (HT) to total thyroidectomy (TT), found comparable long-term oncological outcomes for low-risk papillary thyroid cancer (LRPTC) 1-4 cm in diameter, whereas postoperative complication rates were markedly lower for HT. To refine individual treatment plans, HT should be combined with ipsilateral central lymph node dissection and intraoperative frozen section analysis for staging. Based on recent evidence from studies and in consideration of individual risk factors, patients with LRPTC can be offered the concept of HT as an alternative to the standard TT. A prerequisite for the treatment selection and decision is a comprehensive patient clarification of the possible advantages and disadvantages of both approaches.

Impact of endoscopic surveillance on mortality of metachronous esophageal and head and neck cancer after esophageal endoscopic resection

BACKGROUND AND AIM

As more superficial esophageal cancer (EC) patients are being treated with endoscopic resection (ER), it is important to understand the outcomes, including survival data, of patients who develop metachronous EC and head and neck cancer (HNC). We aimed to evaluate the long-term surveillance and survival outcomes of metachronous EC and HNC after esophageal ER.

METHODS

This study included 627 patients who underwent ER of superficial esophageal squamous cell carcinoma from 2008 to 2016 and were generally followed by annual or biannual esophagogastroduodenoscopy up to 2019 at Osaka International Cancer Institute. Data on metachronous cancer development and causes of death were collected from an integrated database of hospital-based cancer registry and Vital Statistics of Japan.

RESULTS

During a median (range) follow-up period of 67.4 (3.8-142.7) months, 230 patients (36.7%) developed 500 metachronous ECs and 126 patients (20.1%) developed 239 metachronous HNCs, post-ER of index EC. The 3-year, 5-year, and 7-year cumulative incidences were 25.8%, 36.0%, and 43.6% for metachronous EC and 10.9%, 16.0%, and 26.9% for metachronous HNC, respectively. No patients died of metachronous EC, and only seven patients (1.1%) died of metachronous HNC. The 3-year, 5-year, and 7-year disease-specific survival rates were 99.8%, 99.6%, and 98.6%, respectively.

CONCLUSIONS

The incidences of metachronous EC and HNC increase with time over 5 years after esophageal ER; therefore, surveillance endoscopy should be continued over 5 years. Endoscopic surveillance is useful for survivors after esophageal ER given the high incidence and extremely low mortality of metachronous EC and HNC.

Role of Extracellular Vesicles in Thyroid Physiology and Diseases: Implications for Diagnosis and Treatment

Extracellular vesicles are spherical subcellular structures delimited by a lipid bilayer and released by most cells in the human body. They are loaded with a myriad of molecules (i.e., nucleic acids and proteins) depending on their cell of origin and provide the ability to transmit a message to surrounding or distant target cells. In several organs, including the thyroid, abundant recent literature reports that extracellular vesicles are responsible for intercellular communication in physiological and pathological processes, and that their utilization as a potential biomarker of pathological states (i.e., cancer, autoimmune diseases) or as therapeutic delivery vehicles promise clinical options. In this review, we present the current knowledge and understanding regarding the role of extracellular vesicles in developing thyroid diseases and diagnosis.

The decrease in the incidence of malignant tumors as a consequence of the epidemic of COVID-19

In 2020 we observed a sudden decline in cancer incidence in Russia in comparison with 2019. The age-standardized rates (ASR) per 100,000 population of cancers that were on increase before 2019 dropped abruptly including cancers of the colorectum, prostate, breast, thyroid, kidney, while for those cancers that steadily decreased including cancers of the lung and stomach, the decrease has speeded up.

The difference between predicted and actual number of cases registered in 2020 was 98 142 for all cancers, 24 172 for skin cancer (excluding melanoma), 13202 – for prostate cancer 11 660 – for breast cancer, 9570 – for colorectal cancer, 7235 – for lung cancer, 5450 – for kidney cancer, 3506 for gastric cancer, 2744 for urinary bladder cancer, 2436 – thyroid cancer and 2080 for melanoma.

The observed decrease in cancer incidence in 2020 reflects the decrease in the detection rate of cancer. Following arguments might explain this decrease. First the individuals with complains or symptoms who in normal situation would seek medical advice might have barriers for consulting doctor due to isolation and lockdowns. For the same reason the coverage of the population by the check-up programs temporarily decreased including screening for breast, cervix, colorectal and prostate cancer. Regrettably there are no data on the population coverage of these screening programs either before (in 2019) or at the time of COVID epidemic (in 2020).

For most of these tumors the effective screening tests are available that if applied correctly with quality control contribute to early diagnosis and consequently to the improvement of survival and decrease in mortality.

The decrease in the detection rate of cancer in 2020 and 2021 (still to be seen) will result in the shift of the stage of cancer at diagnosis from early to late stages. The proportion of cancer patients diagnosed at the stages III–IV will increase and will be followed by increase in mortality from cancer.

The decrease in cancer detection rate is observed in many counties. The Covid‑19 pandemic affected cancer control in Europe. In one third of the countries in Europe the pressure on the health system created by the Covid –19 pandemic caused interruptions in cancer care.

To handle effectively the problem of the underdiagnosis of cancer during the Covid‑19 pandemic we have to address population using all available ways of communication and explain that the decrease in detection rate of cancer will be followed by shifting the stage of detected cancer from early to late stages and this will affect its curability. People should be advised to see doctor immediately for any health problems. To make this advice effective the accessibility of cancer diagnostic and treatment facilities need to return to pre-pandemic level.

Screening programs should be restored. However, they need to be adjusted to the WHO guidelines and the existing international experience. WHO guidelines recommend screening for colorectal, breast and cervical cancer. Cervical cancer screening – preferably using HPV testing that is much more sensitive than cytological testing and could be carried out twice in the life at age 35 and 45 years.

The evidence-based cancer control program will not only help us to overcome the consequences of the pandemic and returning to the pre-pandemic state but also will promote further decline of cancer mortality.

Retrospective analysis of clinical characteristics and risk factors of differentiated thyroid cancer in children

BACKGROUND

The incidence rate of children with thyroid cancer has an increasing trend. This study aimed to investigate the clinical characteristics and therapeutic approaches of differentiated thyroid cancer (DTC) in Chinese children.

MATERIALS AND METHODS

From January 1998 to March 2022, 52 cases undergoing surgical resection in Xinhua Hospital affiliated to Shanghai Jiao Tong University were divided by age (≤ 7 years old: n = 14 and 8-13 years old, n = 38). Treatment methods and clinical features were analyzed to evaluate prognostic factors for oncological outcomes.

RESULTS

Among the 52 cases, the proportion of local invasion in the pre-school group was found to be higher than that in the school-age group (p = 0.01). T stage was significantly different between the two groups (p ≤ 0.05); the proportion of T_1-2 was higher in the school-age group (32 cases, 84.2%), while the proportion of T₄ was higher in the pre-school group (6 cases, 42.8%) relatively. The postoperative complication rate was dramatically higher in pre-school children (p ≤ 0.05). Additionally, the total thyroidectomy rate in the non-recurrent group was slightly higher than that in the recurrent group (p ≤ 0.05). Over half of the recurrent cases had low T stage and low ATA (American Thyroid Association) risk levels at initial diagnosis (78.3 and 51.4%).

CONCLUSION

The local invasion, tumor stage, and recurrent laryngeal nerve (RLN) injury rates of the pre-school group were higher than that of the school-age group, where young age served as a potential hazard in DTC children. Hence, surgeons should emphasize high-risk features and optimize individualized surgical procedures for DTC children.