Unraveling the role of the mitochondrial one-carbon pathway in undifferentiated thyroid cancer by multi-omics analyses

The role of the serine/glycine metabolic pathway (SGP) has recently been demonstrated in tumors; however, the pathological relevance of the SGP in thyroid cancer remains unexplored. Here, we perform metabolomic profiling of 17 tumor-normal pairs; bulk transcriptomics of 263 normal thyroid, 348 papillary, and 21 undifferentiated thyroid cancer samples; and single-cell transcriptomes from 15 cases, showing the impact of mitochondrial one-carbon metabolism in thyroid tumors. High expression of serine hydroxymethyltransferase-2 (SHMT2) and methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) is associated with low thyroid differentiation scores and poor clinical features. A subpopulation of tumor cells with high mitochondrial one-carbon pathway activity is observed in the single-cell dataset. SHMT2 inhibition significantly compromises mitochondrial respiration and decreases cell proliferation and tumor size in vitro and in vivo. Collectively, our results highlight the importance of the mitochondrial one-carbon pathway in undifferentiated thyroid cancer and suggest that SHMT2 is a potent therapeutic target.

Surgical Outcomes in Patients With Low-risk Papillary Thyroid Microcarcinoma From MAeSTro Study: Immediate Operation Versus Delayed Operation After Active SurveillanceA Multicenter Prospective Cohort Study

OBJECTIVE

To investigate surgical, and clinical outcomes in patients with low-risk papillary thyroid microcarcinoma (PTMC) according to treatment options [immediate operation (IOP) vs delayed operation after active surveillance (AS) (DOP)].

BACKGROUND

AS has been adopted as an alternative to immediate surgery in patients with low-risk PTMC. Although some patients undergo surgery during AS, there is little information on surgical, and clinical outcomes after delayed operation after AS.

METHODS

A multicenter prospective cohort study including 1177 patients was conducted at 3 tertiary hospitals in Korea from June 2016 to January 2020. Patients with low-risk PTMC were enrolled. The participants were self-assigned into AS or IOP, and during AS, the patients underwent surgery if there were signs of disease progression or if the patient's choice changed.

RESULTS

A total of 516 patients underwent operation; 384 (74.4%) in the IOP group and 132 (25.6%) in the DOP group. Compared with the IOP group, the DOP group was significantly associated with a larger tumor size ( P =0.002), higher rates of lymphatic invasion ( P =0.002), and multifocality ( P =0.008). However, the rates of total thyroidectomy, postoperative hypoparathyroidism and vocal cord palsy did not differ significantly between the groups ( P = 0.283, P =0.184, and P =0.284, respectively). Of the 132 patients in the DOP group, disease progression was present in 39 (29.5%) patients. The DOP group with disease progression had a significantly higher rate of lymph node metastasis ( P =0.021) and radioiodine therapy ( P =0.025) than the DOP group without disease progression.

CONCLUSIONS

These results suggest that AS might be considered an alternative treatment option for patients with low-risk PTMC regarding the extent of thyroidectomy and postoperative complications in the DOP group. To assess oncologic outcomes, long-term follow-up will be needed.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02938702.

Incorporation of Cell-Adhesive Proteins in 3D-Printed Lipoic Acid-Maleic Acid-Poly(Propylene Glycol)-Based Tough Gel Ink for Cell-Supportive Microenvironment

In extrusion-based 3D printing, the use of synthetic polymeric hydrogels can facilitate fabrication of cellularized and implanted scaffolds with sufficient mechanical properties to maintain the structural integrity and physical stress within the in vivo conditions. However, synthetic hydrogels face challenges due to their poor properties of cellular adhesion, bioactivity, and biofunctionality. New compositions of hydrogel inks have been designed to address this limitation. A viscous poly(maleate-propylene oxide)-lipoate-poly(ethylene oxide) (MPLE) hydrogel is recently developed that shows high-resolution printability, drug-controlled release, excellent mechanical properties with adhesiveness, and biocompatibility. In this study, the authors demonstrate that the incorporation of cell-adhesive proteins like gelatin and albumin within the MPLE gel allows printing of biologically functional 3D scaffolds with rapid cell spreading (within 7 days) and high cell proliferation (twofold increase) as compared with MPLE gel only. Addition of proteins (10% w/v) supports the formation of interconnected cell clusters (≈1.6-fold increase in cell areas after 7-day) and spreading of cells in the printed scaffolds without additional growth factors. In in vivo studies, the protein-loaded scaffolds showed excellent biocompatibility and increased angiogenesis without inflammatory response after 4-week implantation in mice, thus demonstrating the promise to contribute to the printable tough hydrogel inks for tissue engineering.

Differential Oxidative Stress Responses in Type II Airway Epithelial Cells Impact Premature Senescence and Lung Fibrosis Susceptibility

PURPOSE/OBJECTIVE(S)

Radiation-Induced Pulmonary Fibrosis (RIPF) is a late toxicity characterized by premature senescence in Type II airway epithelial cells (AECII) and accumulation of alternatively activated (M2) macrophages. Differential susceptibility to RIPF is observed across mouse strains. Based on our prior study of the effects of macrophage variation on RIPF, we hypothesized that intrinsic differences in AECII oxidative stress response across mouse strains also impact susceptibility to RIPF.

MATERIALS/METHODS

Ten-week-old female mice from C57L, C57BL6 and C3H/HeN strains were exposed to thoracic irradiation (5x6 Gy, n>5 per group). Fifteen weeks after radiation, lung tissue was collected and examined with Masson-Trichrome staining (histologic changes) and β-galactosidase activity assay (senescence). AECII prepared from mice of each strain were exposed to irradiation. To assess differential gene expression, total RNA was extracted and assessed with a multiplex analysis platform and quantitative PCR. Senescence was assessed by β-galactosidase activity assay in primary AECII after irradiation or after co-culture with M2 macrophages polarized with IL13.

RESULTS

Susceptibility to radiation-induced lung injury, survival, and premature AECII senescence vary by mouse strain: C57L (fibrosis-prone), C57BL6J (-intermediate) and C3H/HeN (-resistant). Enriched AECII from each strain exhibited differential expression of genes related to inflammatory responses including SASP production after irradiation. Minimal increased expression of Il1r1 was observed in irradiated and unirradiated AECII from C3H/HeN, however Il1rn levels were markedly elevated in response to irradiation. The expression of Thioredoxin (Txn) and Thioredoxin reductase 1 (Txnrd1) in AECII from C3H/HeN was significantly higher than those observed in other strains. In Vivo, C3H/HeN mouse lungs exhibited the least premature senescence in AECII after irradiation. Premature senescence in AECII irradiated In Vitro or co-cultured with superoxide anion-producing M2 macrophages was substantially less in AECII from C3H/HeN compared to other strains.

CONCLUSION

A comparison of primary AECII from three different mouse strains identified intrinsic differences in expression of major inflammatory signaling (IL1R and IL1RN) and redox homeostasis status (TXN and TXNDR1) molecules. This study is the first to demonstrate that intrinsic differences in AECII impacts susceptibility to premature senescence and lung fibrosis after irradiation.

Predictors of Early and Late Response to Esomezol and Lifestyle Modification in Adults With Laryngopharyngeal Reflux Disease: A Prospective, Multicenter, Open-Label Cohort Study

OBJECTIVES

This study aimed to assess predictors of the response to varying durations of proton pump inhibitor (PPI) use and lifestyle modification treatment for laryngopharyngeal reflux disease (LPRD).

METHODS

Between October 2014 and June 2016, a prospective, multicenter, open-label, single-cohort, intention-to-treat, observational study was conducted at eight referral hospitals across the Republic of Korea to examine predictors of early and late response to treatment in adult patients (age ≥19 years) with LPRD. Participants underwent standard treatment (PPI [Esomezol] and lifestyle modification) for 3 months. Response to treatment was defined as greater than 50% improvement in reflux symptom index score. The primary outcome was potential predictors of treatment response at 1 and 3 months. The secondary outcome was potential predictors distinguishing early from late responders.

RESULTS

In total, 394 patients were enrolled. Improved sleep habits was a positive predictor (odds ratio [OR], 1.785; 95% confidence interval [CI], 1.06-3.007; P=0.029), while initial alcohol consumption (OR, 0.587; 95% CI, 0.355-0.969; P=0.037) and past medication history (OR, 0.438; 95% CI, 0.215-0.891; P=0.005) were negative predictors of response after 1 month of treatment. High pre-reflux finding score was a positive predictor (OR, 1.187; 95% CI, 1.049- 1.344; P=0.007), while male sex (OR, 0.516; 95% CI, 0.269-0.987; P=0.046), higher depression score (OR, 0.867; 95% CI, 0.784-0.958; P=0.005), and past thyroid hormone medication history (OR, 0.161; 95% CI, 0.033-0.788; P=0.024) were negative predictors of response after 3 months of treatment. Past medication history (OR, 0.438; 95% CI, 0.215-0.891; P=0.023) was the only negative predictor for early responders compared to late responders.

CONCLUSION

Adult patients with LPRD and a history of prior medication use may require longer treatment durations to achieve a therapeutic response. Future research should explore the incorporation of diverse treatment approaches to improve treatment outcomes for patients exhibiting negative prognostic indicators.

Clinical Practice Guidelines for Oropharyngeal Dysphagia

OBJECTIVE

Dysphagia is a common clinical condition characterized by difficulty in swallowing. It is sub-classified into oropharyngeal dysphagia, which refers to problems in the mouth and pharynx, and esophageal dysphagia, which refers to problems in the esophageal body and esophagogastric junction. Dysphagia can have a significant negative impact one's physical health and quality of life as its severity increases. Therefore, proper assessment and management of dysphagia are critical for improving swallowing function and preventing complications. Thus a guideline was developed to provide evidence-based recommendations for assessment and management in patients with dysphagia.

METHODS

Nineteen key questions on dysphagia were developed. These questions dealt with various aspects of problems related to dysphagia, including assessment, management, and complications. A literature search for relevant articles was conducted using Pubmed, Embase, the Cochrane Library, and one domestic database of KoreaMed, until April 2021. The level of evidence and recommendation grade were established according to the Grading of Recommendation Assessment, Development and Evaluation methodology.

RESULTS

Early screening and assessment of videofluoroscopic swallowing were recommended for assessing the presence of dysphagia. Therapeutic methods, such as tongue and pharyngeal muscle strengthening exercises and neuromuscular electrical stimulation with swallowing therapy, were effective in improving swallowing function and quality of life in patients with dysphagia. Nutritional intervention and an oral care program were also recommended.

CONCLUSION

This guideline presents recommendations for the assessment and management of patients with oropharyngeal dysphagia, including rehabilitative strategies.

Guideline for the Surgical Management of Locally Invasive Differentiated Thyroid Cancer From the Korean Society of Head and Neck Surgery

The aim of this study was to develop evidence-based recommendations for determining the surgical extent in patients with locally invasive differentiated thyroid cancer (DTC). Locally invasive DTC with gross extrathyroidal extension invading surrounding anatomical structures may lead to several functional deficits and poor oncological outcomes. At present, the optimal extent of surgery in locally invasive DTC remains a matter of debate, and there are no adequate guidelines. On October 8, 2021, four experts searched the PubMed, Embase, and Cochrane Library databases; the identified papers were reviewed by 39 experts in thyroid and head and neck surgery. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to assess the quality of evidence, and to develop and report recommendations. The strength of a recommendation reflects the confidence of a guideline panel that the desirable effects of an intervention outweigh any undesirable effects, across all patients for whom the recommendation is applicable. After completing the draft guidelines, Delphi questionnaires were completed by members of the Korean Society of Head and Neck Surgery. Twenty-seven evidence-based recommendations were made for several factors, including the preoperative workup; surgical extent of thyroidectomy; surgery for cancer invading the strap muscles, recurrent laryngeal nerve, laryngeal framework, trachea, or esophagus; and surgery for patients with central and lateral cervical lymph node involvement. Evidence-based guidelines were devised to help clinicians make safer and more efficient clinical decisions for the optimal surgical treatment of patients with locally invasive DTC.

Assessment of Esophageal Reconstruction via Bioreactor Cultivation of a Synthetic Scaffold in a Canine Model

Objectives

The use of tissue-engineered materials for esophageal reconstruction is a technically challenging task in animal and requires bioreactor training for enhancing cellular reactivity. Recently, there have been many attempts at esophageal tissue engineering, but the success rate has been limited due to difficulty in initial epithelialization in the special environment of peristalsis. The purpose of this study was to evaluate the potential of an artificial esophagus that can enhance the regeneration of esophageal mucosa and muscle through the optimal combination of a double-layered polymeric scaffold and a custom-designed MSC-based bioreactor system in canine model.

Methods

We fabricated a novel double-layered scaffold as a tissue-engineered esophagus using an electrospinning technique. Prior to transplantation, human-derived mesenchymal stem cells were seeded into the lumen of the scaffold, and bioreactor cultivation was performed to enhance cellular reactivity. After 3 days of cultivation using a bioreactor system, tissue-engineered artificial esophagus was transplanted into a partial esophageal defect (5 x 3 cm-long resection) in a canine model.

Results

From the SEM analysis, electrospun fibers in a tubular scaffold were found to be randomly and circumferentially oriented toword the inner and outer surfaces, respectively. Complete recovery of the esophageal mucosa was confirmed by endoscopic analysis and SEM. Esophagogastroduodenoscopy (EGD) and CT analysis also showed that there were no signs of leakage or stricture and that there were normal lumen with complete epithelialization. Significant regeneration of the mucosal layer was observed by keratin 5 immunostaining. From the α-SMA immunostaining, esophageal muscle regeneration was significantly increased in the graft (12 months) group compared with the graft (6 months) group.

Conclusion

A custom-designed bioreactor cultured electrospun PU scaffolds can be a promising approach for esophageal tissue engineering.

Effect of postoperative radiotherapy for patients with differentiated thyroid cancer

OBJECTIVE

We evaluated the efficacy and safety of postoperative radiotherapy (PORT) for differentiated thyroid cancer (DTC) with high risk features.

MATERIALS AND METHODS

This retrospective study analyzed 187 patients treated for DTC from 1985 to 2019. DTC referred to nonanaplastic thyroid cancer originating from follicular cells. PORT was defined as the administration of external beam radiation to the thyroid and regional lymph nodes following surgery for initially diagnosed DTC. The patients were included in the analysis if they received PORT or exhibited any of the following features: (a) pT4 or pN1b according to the 8th American Joint Committee on Cancer, (b) poorly differentiated thyroid cancer (PDTC), or (c) unfavourable variants such as anaplastic foci and etc. After 1:1 propensity matching, a total of 108 patients were analyzed according to PORT receipt. The median follow-up duration of the matched group was 10.4 years.

RESULTS

After matching, most of the variables became balanced, but the PORT group still had more PDTC and DTC with anaplastic foci. Radioactive iodine (RAI) was less frequently administered in the PORT group. PORT yielded a significantly higher 5-year locoregional recurrence free survival (LRFS) than the No PORT group (5-year LRFS 86.1% vs. 72.7%, p = 0.022), but the 10-year cancer specific survival (CSS) was similar between them (97.8% vs. 85.9%, p = 0.122). The multivariable analysis indicated that PORT was a favourable prognostic factor (Hazard ratio 0.3, 95% Confidence interval 0.1-0.8, p = 0.02) for LRFS, but not for CSS. Among 133 patients without PORT for initial disease, 39 of them received salvage surgery followed by salvage PORT. No severe toxicity after PORT was reported.

CONCLUSION

PORT reduced locoregional recurrence in DTC patients without severe toxicity. PORT can be an effective and safe treatment to improve locoregional control in DTC with high risk features. However, further study is warranted to identify those who can benefit from PORT.

Control of maleic acid-propylene diepoxide hydrogel for 3D printing application for flexible tissue engineering scaffold with high resolution by end capping and graft polymerization

BACKGROUND

Control of 3D printing of highly tough hydrogel inks with adequate printability, scaffold fidelity and mechanical properties are highly desirable for biomedical and tissue engineering applications. However, developing a biocompatible tough ink with high-resolution printability, biodegradability, self-healing, adhesion, and integration with surrounding tissues is a big challenge in 3D printing. The aim of this study was to develop extrusion-based 3D printing of viscous hydrogel composing of maleic acid and propylene diepoxide by controlling continuous mechanisms of condensation and radical polymerization.

METHODS

The molecular weight of highly adhesive propagating poly(malate-co-propylene oxide) copolymer was controlled by capping its growing chain with mono-functional lipoic acid with different compositions during condensation reaction to form lipoic acid capped gel (LP-capped gel). Poly(ethylene oxide)-diacrylate, PEGDA, is graft-polymerized to the LP-capped backbone polymer (MPLE gel) by UV irradiation during 3D printing process to control the properties of gel printability, mechanical properties, and cell adhesiveness and post-printing fidelity of the printed scaffolds with high resolution and mechanical properties (MPLE scaffold). The scaffolds in complex geometries have been printed out in diverse forms with addition of model drugs with different molecular weights and chemical structures. Both the highly adhesive LP-capped gel and printing-controlled MPLE gel/scaffolds are diversely characterized and compared with for their applications to the extrusion-based printability, including biocompatibility, self-healing, drug releasing, adhesiveness, multi-layered high-resolution printing. Further in vitro/in vivo tests were done to observe cytotoxicity, immune response and tissue formation by using different cells in mice model.

RESULTS

LP-capped hydrogel from maleic acid and propylene diepoxide gel showed control of gel properties with lipoic acid with one function group of thiol during condensation reaction, and the ratio at 1:0.3 (w/v) between LP-capped gel and PEGDA was chosen for the optimal results during radical polymerization process for 3D printing at high resolution (90-140 μm in strut thickness) with various complex geometries (lattice, rhombus, and honeycomb). The hydrogel showed excellent properties of self-healing, mechanical strength, biocompatibility, etc. In addition, the long-term release profiles of bioactive molecules were well-controlled by incorporating drugs of high molecular bovine serum albumin (BSA, 21 days, 98.4 ± 0.69%), or small molecule ornidazole (ORN, 14 days, 97.1 ± 1.98%) into the MPLE gel scaffolds for the tests of potential therapeutic applications. More importantly, the MPLE gels represents excellent in vitro cyto-compatibility against osteoblast-like cells (MC3T3) with viability value at 96.43% ± 7.48% over 7 culturing days. For in-vivo studies, the flexible MPLE scaffolds showed significant improvement on angiogenesis with minor inflammatory response after 4-week implantation in mice.

CONCLUSION

The MPLE gel inks was well-controlled for the fabrication of flexible complex tissue engineering scaffold with high resolutions, shear-thinning, 3D printability and post-printing fidelity, by modulating the composition of the highly adhesive LP-capped gel and inert PEGDA as well as end capping of lipoic acid to the propagating poly(malate-co-propylene oxide) copolymer. The gel ink demonstrated its excellent printability, in vitro/in vivo biocompatibility and mechanical properties as well as sustained drug release from the gel.

Progression of Low-Risk Papillary Thyroid Microcarcinoma During Active Surveillance: Interim Analysis of a Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma in Korea

Background: Active surveillance (AS) is an alternative to thyroidectomy for the management of low-risk papillary thyroid microcarcinoma (PTMC). However, prospective AS data collected from diverse populations are needed. Methods: This multicenter prospective cohort study enrolled patients from three referral hospitals in Korea. The participants were self-assigned into two groups, AS or immediate surgery. All patients underwent neck ultrasound every 6-12 months to monitor for disease progression. Progression under AS was evaluated by a criterion of tumor size increment by 3 mm in one dimension (3 mm), 2 mm in two dimensions (2 × 2 mm), new extrathyroidal extension (ETE), or new lymph node metastasis (LNM), and a composite outcome was defined using all four criteria. Results: A total of 1177 eligible patients with PTMC (919 female, 78.1%) with a median age of 48 years (range 19-87) were enrolled; 755 (64.1%) patients chose AS and 422 (35.9%) underwent surgery. Among 755 patients under AS, 706 (female 537, 76.1%) underwent at least two ultrasound examinations and were analyzed. Over a follow-up period of 41.4 months (standard deviation, 16.0), 163 AS patients (23.1%) underwent surgery. Progression defined by the composite outcome was observed in 9.6% (68/706) of patients, and the 2- and 5-year progression estimates were 5.3% and 14.2%, respectively. The observed progression rates were 5.8% (41/706) and 5.4% (38/706) as defined by tumor size enlargement by 3 mm and 2 × 2 mm, respectively, and 1.3% (9/706) and 0.4% (3/706) for new LNM and ETE, respectively. No distant metastases developed during AS. In multivariate logistic regression analysis examining variables associated with progression under AS, age at diagnosis <30 years (odds ratio [OR], 2.86; 95% confidence interval [CI], 1.10 - 7.45), male sex (OR, 2.48; 95% CI, 1.47 - 4.20), and tumor size ≥6 mm (OR, 1.89; 95% CI, 1.09 - 3.27) were independently significant. Conclusions: The progression of low-risk PTMC during AS in the Korean population was low, but slightly higher than previously reported in other populations. Risk factors for disease progression under AS include younger age, male sex, and larger tumor size. Clinical trial registration: Clinicaltrials.gov NCT02938702.

Bell's palsy misdiagnosis: characteristics of occult tumors causing facial paralysis

Objective

The aim of this study was to report the incidence and clinical course of a series of patients who were misdiagnosed with Bell’s palsy and were eventually proven to have occult neoplasms.

Methods

Two hundred forty patients with unilateral facial paralysis who were assessed at the facial nerve reanimation clinic, Victoria Hospital, London Health Science Centre, from 2008 through 2017 were reviewed. Persistent paralysis without recovery was the presenting complaint.

Results

Nine patients (3.8%) who were proven to have occult neoplasms initially presented with a diagnosis of Bell’s palsy. The mean diagnostic delay was 43.5 months. Four patients were proven to have skin cancers, 3 patients had parotid cancers, and 2 patients had facial nerve schwannomas as a final diagnosis. Initial magnetic resonance imaging (MRI) was performed in all 9 patients and 8 underwent a follow-up MRI. An occult tumor was identified upon review of the original MRI in one patient and at follow-up MRI in 8 patients. The mean time interval between the initial and follow-up imaging was 30.8 months. The disease status at most recent follow-up were no evidence of disease in 2 patients (22%) and alive with disease in 7 patients (78%). An irreversible, progressive pattern of facial paralysis combined with pain, multiple cranial neuropathies or history of skin cancer were predictable risk factors for occult tumors. Seven out of the 9 patients (77.8%) underwent at least one type of facial reanimation surgery, and the final subjective results by the surgeon were available for 5 patients. Three out of the 5 (60%) patients who were available for final subjective analysis were reported as Grade III according to the modified House-Brackmann scale.

Conclusion

Occult facial nerve neoplasm should be suspected in patients with progressive and irreversible facial paralysis but the diagnosis may only become evident with follow-up imaging. Facial reanimation surgery is a satisfactory option for these patients.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s40463-022-00591-9.

Expression of defensin-associated gene can be correlated with lymph node metastasis of early stage tongue cancer

BACKGROUND: We aimed to assess the genetic differences between positive and negative lymph node metastasis in early stage tongue cancer.METHODS: A total of 35 cases of tongue cancer with RNAseq data were enrolled in this study. The gene expression profile of the following two groups was compared: 1) N0 group, T stage 1 or 2 with N0 stage; 2) N+ group, T stage 1 or 2 with N+ stage. Using the R and limma packages in the Bioconductor program, we extracted the differentially expressed genes (DEGs). Gene ontology and pathway enrichment analysis were performed using the DAVID online tool. Immune cell infiltration was analyzed using the CIBERSORT online program. Immunochemical staining of the cancer tissue was evaluated and the Cancer Genome Atlas (TCGA) data were analyzed to validate of the identified DEGs. RESULTS: There were no significant differences in infiltration of the 22 types of immune cells. Among a total of 51 DEGs identified, 14 genes were significantly upregulated while 37 genes were significantly downregulated (p<0.01; fold-change >2). Pathway analysis revealed that arachidonic acid metabolism-related pathway, calcium, and muscle contraction pathway were significantly correlated. Among DEGs, following genes were the most significantly different between two groups; DEFB4A, SPRR2B, DEFB103B, SPRR2G, DEFB4B, and FAM25A. Via TCGA data, DEFB4A and DEFB103B were more highly expressed in the N0 group than in the N+ group, although the difference did not achieve statistical significance. Immunochemical staining of cancer tissue revealed the significantly higher expression of defensin in the N0 group.CONCLUSIONS: Defensin (DEFB4A, DEFB103B, DEFB4B) may be a novel biomarker for early regional metastasis in T1/2 tongue cancer.

A Cross-Sectional Survey of Patient Treatment Choice in a Multicenter Prospective Cohort Study on Active Surveillance of Papillary Thyroid Microcarcinoma (MAeSTro)

Background: Active surveillance (AS) is offered as a choice to patients with low-risk papillary thyroid microcarcinoma (PTMC). This study aimed to identify patient and physician factors associated with the choice of AS. Methods: We conducted a cross-sectional survey of patients with low-risk PTMC who were enrolled in a prospective study comparing outcomes following AS and surgery. Patients completed a questionnaire to assess their prior knowledge of the disease, considerations in the decision-making process, and reasons for choosing the treatment. We also surveyed 19 physician investigators about their disease management preferences. Variables affecting the patients' choice of AS, including patients' characteristics and their decision-making process, were analyzed in a multivariable analysis. Results: The response rate of the patient survey was 72.8% (857/1177). Among the patients who responded to the survey, 554 patients (128 male; mean age 49.4 ± 11.6 years; response rate 73.4%) with low-risk PTMC chose AS (AS group), whereas 303 patients (55 male; 46.6 ± 10.7 years; 71.8%) chose immediate surgery (iOP group). In the AS group, 424 patients (76.5%) used a decision aid, and 144 (47.5%) used it in the iOP group. The choice of AS was associated with the following variables: patient age >50 years (odds ratio 1.713 [confidence interval, CI 1.090-2.690], p = 0.020), primary tumor size ≤5 mm (odds ratio 1.960 [CI 1.137-3.379], p = 0.015), and consulting an endocrinologist (odds ratio 114.960 [CI 48.756-271.057], p < 0.001), and use of a decision aid (odds ratio 2.469 [CI 1.320-4.616], p = 0.005). The proportion of patients who were aware of AS before their initial consultation for treatment decision was higher in the AS group than in the iOP group (64.6% vs. 56.8%). Family members were reported to have influenced the treatment decisions more in the iOP group (p = 0.025), whereas the AS group was more influenced by information from the media (p = 0.017). Physicians' attitudes regarding AS of low-risk PTMC tended to be more favorable among endocrinologists than surgeons and all became more favorable as the study progressed. Conclusions: Emerging evidence suggests that physicians' attitudes and communication tools influence the treatment decision of low-risk PTMC patients. Support is needed for patient-centered decision making. (Clinical trial No: NCT02938702).

Risk factors of postoperative hypoparathyroidism after total thyroidectomy in pediatric patients with thyroid cancer

PURPOSE

Hypoparathyroidism is the most common complication following thyroidectomy. We investigated the frequency and risk factors of hypoparathyroidism after total thyroidectomy in pediatric patients with thyroid cancer.

METHODS

This retrospective study included 98 patients, diagnosed with thyroid cancer after total thyroidectomy < 20 years of age during 1990-2018 and followed up more than 2 years at Seoul National University Hospital. Hypoparathyroidism was defined as receiving active vitamin D (1-hydroxycholecalciferol or 1,25-dihydroxycholecalciferol) after surgery.

RESULTS

The study included 27 boys (27.6%) and 71 girls (72.4%). The mean age at diagnosis was 14.9 ± 3.7 years. Hypoparathyroidism occurred in 43 (43.9%) patients. Twenty-one (21.4%) patients discontinued active vitamin D less than 6 months, and 14 (14.3%) continued active vitamin D for more than 2 years. Tumor multifocality (Odds ratio (OR) 3.7 vs. single tumor, P=0.013) and preoperative calcium levels (OR 0.2, P=0.028) were independent predictors for developing hypoparathyroidism immediately after total thyroidectomy. In addition, age (OR 0.8, P=0.011) and preoperative calcium levels (OR 0.04, P=0.014) significantly decreased the risk for persistent hypoparathyroidism requiring active vitamin D for more than 2 years.

CONCLUSION

Hypoparathyroidism occurred in about two-fifth after total thyroidectomy in pediatric thyroid cancer. Among them, one-third of patients continued active vitamin D medication for more than 2 years, which was predicted by young age and low preoperative calcium levels.

Hypofractionated radiotherapy for early stage glottic cancer: efficacy of 3.5 Gy per fraction

Purpose

The purpose of this study was to evaluate the treatment outcomes and toxicity profile of patients with early glottic cancer who underwent hypofractionated radiation therapy (RT) with 3.5 Gy per fraction.

Materials and Methods

A retrospective review was performed of the medical records of 35 patients with early stage (T1-2N0M0) glottic cancer who underwent definitive RT. The dose fractionation scheme was 59.5 Gy in 17 fractions. Posterior commissure was excluded from the clinical target volume (CTV) for 26 patients (74.3%) without glottic lesions close to this region.

Results

With a median follow-up of 16.23 months (range, 6.82 to 67.15 months), no local, regional, or distant recurrence was reported. Acute hoarseness (65.7%), mucositis (68.6%), radiation dermatitis (60.0%) was frequent. One patient (2.9%) reported grade 3 acute toxicity (mucositis) and there was no grade 4–5 acute toxicity. There was no grade ≥3 late toxicities; however, grade 1 late intermittent hoarseness was frequent (45.7%). The receiver operative characteristic analysis revealed that mean hypopharyngeal dose was predictive for acute grade ≥2 mucositis (area under the curve=0.9314; 95% confidence interval, 0.8524–1). The optimal threshold of mean hypopharyngeal dose for occurrence of acute grade ≥2 mucositis was 26.31 Gy, with a specificity and sensitivity of 83.3% and 88.2%, respectively.

Conclusion

Hypofractionated RT with fraction size of 3.5 Gy for early glottic cancer is effective. The hypopharyngeal mean dose could predict the occurrence of grade ≥2 acute mucositis. The posterior commissure can be safely excluded from the CTV.

Manufacturing of self-standing multi-layered 3D-bioprinted alginate-hyaluronate constructs by controlling the cross-linking mechanisms for tissue engineering applications

3D bioprinting of self-supporting stable tissue and organ structure is critically important in extrusion-based bioprinting system, especially for tissue engineering and regenerative medicine applications. However, the development of self-standing bioinks with desired crosslinking density, biocompatibility, tunable mechanical strength and other properties like self-healing, in situ gelation, drug or protein incorporation is still a challenge. In this study, we report a hydrogel bioink prepared from alginate (Alg) and hyaluronic acid (HA) crosslinked through multiple crosslinking mechanisms, i.e., acyl-hydrazone, hydrazide interactions and calcium ions. These Alg-HA gels were highly dynamic and shear-thinning with exceptional biocompatibility and tunable mechanical properties. The increased dynamic nature of the gels is mainly chemically attributed to the presence of acyl-hydrazone bonds formed between the amine groups of the acyl-hydrazide of alginate and the monoaldehyde of the hyaluronic acid. Among the different combinations of Alg-HA gel compositions prepared, the A5H5 (Alginate-acyl-hydrazide: HA-monoaldehyde, ratio 50:50) one showed a gelation time of ~60 s, viscosity of ~400 Pa.s (at zero shear rate), high stability in various pH solutions and increased degradation time (>50 days) than the other samples. The A5H5 gels showed high printability with increased post-printing stability as observed from the 3D printed structures (e.g., hollow tube (~100 layers), porous cube (~50 layers), star, heart-in, meniscus and lattice). The scanning electron microscopy analysis of the 3D constructs and hydrogels showed the interconnected pores (~181 µm) and crosslinked networks. Further, the gels showed sustained release of 5-amino salicylic acid and bovine serum albumin. Also, the mechanical properties were tuned by secondary crosslinking via different calcium concentrations. In vitro assays confirmed the cytocompatibility of these gels, where the 3D bioprinted lattice and tubular (~70 layers) constructs demonstrated high cell viability under fluorescence analysis. In in vivo studies, Alg-HA gel showed high biocompatibility (>90%) and increased angiogenesis (3 folds) and reduced macrophage infiltration (2-fold decrease), demonstrating the promising potential of these hydrogels in 3D bioprinting applications for tissue engineering and regenerative medicine with tunable properties.

Deep learning model for tongue cancer diagnosis using endoscopic images

In this study, we developed a deep learning model to identify patients with tongue cancer based on a validated dataset comprising oral endoscopic images. We retrospectively constructed a dataset of 12,400 verified endoscopic images from five university hospitals in South Korea, collected between 2010 and 2020 with the participation of otolaryngologists. To calculate the probability of malignancy using various convolutional neural network (CNN) architectures, several deep learning models were developed. Of the 12,400 total images, 5576 images related to the tongue were extracted. The CNN models showed a mean area under the receiver operating characteristic curve (AUROC) of 0.845 and a mean area under the precision-recall curve (AUPRC) of 0.892. The results indicate that the best model was DenseNet169 (AUROC 0.895 and AUPRC 0.918). The deep learning model, general physicians, and oncology specialists had sensitivities of 81.1%, 77.3%, and 91.7%; specificities of 86.8%, 75.0%, and 90.9%; and accuracies of 84.7%, 75.9%, and 91.2%, respectively. Meanwhile, fair agreement between the oncologist and the developed model was shown for cancer diagnosis (kappa value = 0.685). The deep learning model developed based on the verified endoscopic image dataset showed acceptable performance in tongue cancer diagnosis.

Re-irradiation for recurrent or second primary head and neck cancer

Purpose

To investigate the efficacy and safety of intensity-modulated radiotherapy (IMRT)-based re-irradiation (reRT) for recurrent or second primary head and neck cancer (HNC).

Materials and Methods

Patients who underwent IMRT-based reRT for recurrent or second primary HNC between 2007 and 2019 at two institutions were included. Medical records and dosimetric data were retrospectively reviewed. Overall survival (OS), progression-free survival (PFS), severe late toxicities, and clinicopathological prognostic factors were analyzed.

Results

A total of 42 patients were analyzed. With a median follow-up of 15.1 months (range, 3.7 to 85.8 months), the median OS was 28.9 months with a 2-year OS rate of 54.6%. The median PFS and 2-year PFS rates were 10.0 months and 30.9%, respectively. Multivariate analysis showed that good performance (Eastern Cooperative Oncology Group [ECOG] 0 or 1), a longer time interval (≥24 months) between radiotherapy courses, and higher reRT dose (>60 Gy) were significantly favorable factors for OS (all p < 0.05). Higher reRT dose and salvage surgery were significantly associated with improved PFS (all p < 0.05). Regarding the Multi‐Institution Reirradiation (MIRI) Collaborative RPA classification, the 2-year OS rates of each class were 87.5% in class I, 51.8% in class II, and 0% in class III (p = 0.008). Grade ≥3 late toxicity was reported in 10 (23.8%) patients. There was no significant factor associated with increased late toxicities.

Conclusion

IMRT-based reRT should be considered as a treatment option for patients with recurrent or second primary HNC. Further trials are needed to establish a subset of patients who may benefit from reRT without severe late toxicity.

Investigation of Snoring and Obstructive Sleep Apnea Using Portable Polysomnography in Patients with Temporomandibular Disorder

Objective

To investigate snoring and obstructive sleep apnea (OSA) in patients with temporomandibular disorder (TMD) using portable polysomnography and identify sex-based differences in clinical features and sleep-related results.

Methods

Seventy consecutive patients (44 female; mean age, 46.6918.18 years) with myofascial pain-associated TMD, diagnosed based on the criteria for TMD Axis I, were enrolled. Sleep quality and quantity were measured using portable polysomnography. Clinical characteristics were investigated using well-structured standardized reports on clinical signs and symptoms, questionnaires, and clinical examination by TMD specialists.

Results

Among 70 TMD patients, 50.0% had OSA and 15.7% had snoring, with no sex-based differences. The mean Mallampati scores for OSA prediction (2.69±1.12 vs. 1.70±0.82, p<0.001), mean body mass index (BMI) (24.94±1.78 vs. 22.02±2.24, p<0.001), and ratio of overweight patients (57.7 vs. 11.4%) with BMI ≥25 were significantly higher in males than in females (all p<0.001). Conversely, the mixed sleep apnea index was significantly higher in females than in males (0.81±0.80 vs. 0.44±0.54, p=0.022). Female sex was associated with the absence of snoring (OR=0.146, p=0.022). Based on the area under curve (AUC) value for snoring prediction, Mallampati score was the strongest predictor (AUC>0.932, p<0.001), followed by BMI, overweight, and obstructive sleep apnea index (AUC>0.8, all p<0.001).

Conclusions

Our results support the necessity of investigating sex-based differences when examining sleep problems, including snoring and OSA, in TMD patients. Mallampati scoring could be a useful tool for physical examination prior to polysomnography. Sleep and biopsychosocial factors are important for the diagnosis and treatment of TMD.

Three-Dimensional Printed Design of Antibiotic-Releasing Esophageal Patches for Antimicrobial Activity Prevention

Pharyngoesophageal defects can cause exposure to various bacterial flora and severe inflammation. We fabricated a biodegradable polycaprolactone (PCL) patch composed of both thin film and three-dimensional (3D) printed lattice, and then investigated the efficacy of pharyngoesophageal reconstruction by using 3D printed antibiotic-releasing PCL patches that inhibited early inflammation by sustained tetracycline (TCN) release from both thin PCL films and printed rods implanted in esophageal partial defects. PCL was 3D printed in lattice form on a presolution casted PCL thin film at ∼100 μm resolution. TCN was loaded onto the PCL-printed patches by 3D printing a mixture of TCN and PCL particles melted at 100°C. TCN exhibited sustained release in vitro for over 1 month. After loading TCN, the patches showed decreased tensile strength and Young's modulus, and less than 20% TCN was slowly released from the 2.5% TCN-loaded PCL patches over 150 days. Cytotoxicity tests of extract solutions from patch samples demonstrated excellent in vitro cell compatibility. Antibiotic-releasing PCL patches were then transplanted into partial esophageal defects in rats. Microcomputed tomography analysis revealed no leak of orally injected contrast agent in the entire esophagus. Tissue remodeling was examined through histological responses of M1 and M2 macrophages. In particular, the 1% and 3% TCN patch groups exhibited significant muscle layer regeneration by desmin immunostaining. Further histological and immunofluorescence analyses revealed that the 1% and 3% TCN patch groups exhibited the best esophageal regeneration according to reepithelialization, neovascularization, and elastin texture around the implanted sites. Our antibiotic-releasing patch successfully consolidates the regenerative potential of esophageal muscle and mucosa and the antibacterial activity of TCN for 3D esophageal reconstruction. Impact statement Anastomosis site leakage and necrosis after pharyngoesophageal transplantation inevitably causes mortality because the mediastinum and neck compartments become contaminated. Herein, we present antibiotic-releasing pharyngoesophageal patch that prevents saliva leakage and has an antimicrobial effect. We have demonstrated antibiotic release profile and mechanical properties for esophageal transplantation. Upon esophageal transplantation of antibiotic-releasing polycaprolactone patches, antimicrobial effects and muscle regeneration around the graft sites were clearly identified in the group containing 1% and 3% of tetracycline. The esophageal graft led to the remarkable recovery throughout reepithelialization, neovascularization, and elastin texture of around the implanted sites. We believe that current system is capable of various applications that require antibacterial in vivo.

Thyroid nodules in childhood-onset Hashimoto's thyroiditis: Frequency, risk factors, follow-up course and genetic alterations of thyroid cancer

OBJECTIVE

We evaluated the frequency, risk factors and the follow-up outcomes of thyroid nodules, and genetic alterations in thyroid cancer, in youth with childhood-onset Hashimoto thyroiditis (HT) residing in an iodine-sufficient country.

DESIGN

A retrospective cohort study.

PATIENTS AND MEASUREMENTS

A total of 213 patients (194 females, mean age 10.6 years at the time of HT diagnosis) were ultrasonographically evaluated. Thyroid nodules were categorized using the Korean Thyroid Imaging Reporting and Data System (K-TIRADS) and the American College of Radiology Thyroid Imaging Reporting and Data System (ACR-TI-RADS).

RESULTS

Thyroid nodules were detected in 40 (18.8%) patients over a median follow-up period of 3.4 years, usually after the onset of puberty. A family history of thyroid disease (hazard ratio 2.1, p = .031) was predictive of thyroid nodule detection. Papillary thyroid carcinoma (PTC) was diagnosed in 9 (4.2% of all and 22.5% of nodule-positive patients). The malignant nodules had a higher K-TIRADS or ACR-TI-RADS risk level compared with benign nodules (p < .01 for both). Genetic alterations were revealed in 7 (BRAF^V600E in 6 and RET-ERC1 fusion in 1) of the eight available tumour tissue samples. None showed evidence of disease over a median follow-up period of 3.4 years.

CONCLUSIONS

The nodule detection rate was 18.8%, with a 22.5% risk of malignancy among the detected nodules in childhood-onset HT patients, showing increased risk in those with a family history. Additional large-scale studies are required to evaluate the usefulness of K-TIRADS or ACR-TI-RADS risk level for the differentiation of paediatric thyroid nodules.

Alternative non-oral nutrition in a rat model: a novel modified gastrostomy technique

The gastrostomy technique is essential for esophageal reconstruction using a scaffold. To date, there are no established methods to supply nutrients through a gastrostomy tube in rats. The purpose of this study was to analyze the feasibility of a newly modified gastrostomy technique for non-oral nutrition in an adult rat model. We modified the gastrostomy technique for adult rats in a few different ways. (1) The external opening for food injection was made at the midpoint between the ears to prevent damage due to self-harm behaviour. (2) An imbedded subcutaneous tunnel was created between the internal and external openings of the gastrostomy. We compared the efficacy and safety between groups with a T-tube for biliary drainage (TT group, n=14) and a conventional silicone Foley catheter (FC group, n=7) as optimal gastrostomy tubes for in a rat model. We also evaluated the feasibility of the heparin cap connector at the end of gastrostomy tube to control food supply in the TT group (with a cap, n=7; without a cap, n=7). No mortality was observed in the TT group with a cap, whereas most rats in the FC group died within 2 weeks after the procedure. Weight loss decreased significantly in the TT group with a cap compared with all the other groups. The appearance and attitude scores were significantly better in the TT group with a cap. In addition, histologic analysis showed that the TT group a cap showed a marked decrease over time in tissue fibrosis and macrophages compared with the other experimental groups. Therefore, gastrostomy using a silicone T-tube plugged with a cap proved to be a stable and effective option for non-oral feeding in an adult rat model.

NTRK- and RET-fusion-directed therapy in pediatric thyroid cancer yields a tumor response and radioiodine uptake

BACKGROUND

Molecular characterization in pediatric papillary thyroid cancer (PTC), distinct from adult PTC, is important for developing molecular targeted therapies for progressive 131I-refractory PTC.

METHODS

PTC samples from 106 pediatric patients (age: 4.3-19.8 years; 21 boys) who attended Seoul National University Hospital (January 1983-March 2020) were available for genomic profiling. Previous transcriptome data from 125 adult PTCs were used for comparison.

RESULTS

Genetic drivers were found in 80 tumors; 31 with fusion oncogenes (RET in 21, ALK in 6, and NTRK1/3 in 4), 47 with point mutations (BRAFV600E in 41, TERTC228T in 2, and DICER1 variants in 5), and 2 with amplifications. Fusion-oncogene PTCs, predominantly detected in younger patients, presented with a more advanced stage and showed more recurrent or persistent disease than BRAFV600E PTCs, which were detected mostly in adolescents. Pediatric fusion PTCs (in those aged < 10 years) showed lower expression of thyroid differentiation genes, including SLC5A5, than adult fusion PTCs. Two girls with progressive 131I-refractory lung metastases harboring a TPR-NTRK1 or CCDC6-RET fusion received fusion-targeted therapy; larotrectinib and selpercatinib decreased the tumor extent and restored radioiodine uptake. The girl with the CCDC6-RET fusion received 131I therapy combined with selpercatinib, leading to a tumor response. In vitro 125I uptake and 131I clonogenic assays showed that larotrectinib inhibited growth and restored radioiodine avidity.

CONCLUSIONS

In pediatric fusion-oncogene PTC cases with 131I-refractory advanced disease, selective fusion-directed therapy may restore radioiodine avidity and lead to a dramatic tumor response, underscoring the importance of molecular testing in pediatric PTC patients.

FUNDING

The Ministry of Science, ICT & Future Planning (grant number NRF-2016R1A2B4012417 91 and 2019R1A2C2084332), the Ministry of Health & Welfare, Republic of Korea (grant number 92 H14C1277), the Ministry of Education (grant number 2020R1A6A1A03047972), and the Seoul 93 National University Hospital Research Fund (grant number 04-2015-0830).

Radiotherapy Versus Surgery in Early-Stage HPV-positive Oropharyngeal Cancer

Purpose

To compare the outcomes of primary radiotherapy (RT) versus surgery in early-stage human papilloma virus-positive oropharyngeal squamous cell carcinoma (hpv+OPC), and investigate the preoperative clinical factors that can predict the requirement for postoperative adjuvant treatment.

Materials and Methods

This multicenter study included 166 patients with AJCC 8th edition-Stages I-II hpv+OPC. Sixty (36.1%) and 106 (63.9%) patients underwent primary (CC)RT and surgery, respectively. Seventy-eight (73.6%) patients in the surgery group received postoperative (CC)RT.

Results

With a median follow-up of 45.6 months for survivors, the 2-year overall survival (OS), progression-free survival (PFS), and locoregional control (LC) for radiotherapy/surgery were 97.8%/96.4%, 91.1%/92.0%, and 92.9%/93.3%, respectively. In multivariate analyses, patients with synchronous radiologic extranodal extension and conglomeration (ENEcong) of metastatic LNs showed significantly poorer OS (p=0.047), PFS (p=0.001) and LC (p=0.003). In patients undergoing primary surgery, two or more clinically positive LN metastases (OR, 5.15; p=0.004) and LN metastases with ENEcong (OR, 3.75; p=0.009) were predictors of postoperative chemoradiotherapy. No patient in the primary radiotherapy group demonstrated late severe toxicity whereas 3 (2.8%), 1 (0.9%), and 1 (0.9%) patient in the surgery group showed grade 3 dysphagia, grade 3 xerostomia, and fatal oral cavity bleeding.

Conclusion

We found no differences in OS, PFS, and LC between upfront radiotherapy and surgery in stage I-II hpv+OPC which warrants comparison through a prospective trial in the treatment de-escalation era. However, most early-stage hpv+OPC patients undergoing surgery received adjuvant (CC)RT. Pretreatment LN findings were prognostic and predictive for adjuvant treatment.

Effect of Initial Treatment Choice on 2-year Quality of Life in Patients with Low-risk Papillary Thyroid Microcarcinoma

CONTEXT

The long-term quality of life (QoL) in patients with low-risk papillary thyroid microcarcinoma (PTMC) underwent active surveillance (AS) and immediate surgery is unclear.

OBJECTIVE

The aim of this study was to investigate the effect of initial treatment choice on 2-year QoL in patients with low-risk PTMC.

DESIGN, SETTING, AND PARTICIPANTS

We analyzed 2652 QoL surveys from 1055 subjects enrolled in ongoing multicenter prospective cohort study on active surveillance of PTMC, in which the median follow-up duration was 24.4 months.

MAJOR OUTCOME MEASURE

We evaluated QoL of patients with low-risk PTMC according to their treatment modality using generalized estimating equation.

RESULTS

Six hundred and seventy-four subjects (male = 161; mean age = 48.8 ± 11.9 years) with low-risk PTMC chose AS while 381 subjects (male = 75; mean age = 45.7 ± 10.4 years) chose immediate surgery, including lobectomy/isthmusectomy (L/I) and total thyroidectomy (TT). Among the 817 subjects who completed baseline QoL surveys, 2-year QoL was good in order of AS (n = 500), L/I (n = 238), and TT (n = 79) groups after adjustment for age, sex, baseline tumor size, and baseline QoL scores. Among the 101 subjects who changed their treatment from AS to surgery during the follow-up period, 35 subjects who changed treatment due to disease progression had better QoL than 66 subjects who had no disease progression.

CONCLUSIONS

This study identified QoL as a major issue in choosing an initial treatment of low-risk PTMC and highlighted the possibility of using AS as the primary treatment.

Regeneration of irradiation-damaged esophagus by local delivery of mesenchymal stem-cell spheroids encapsulated in a hyaluronic-acid-based hydrogel

Radiation therapy (RT) is a typical treatment for head and neck cancers. Generally, prolonged irradiation of the esophagus causes esophageal fibrosis due to increased reactive oxygen species and proinflammatory cytokines. This study was designed to determine whether catechol-functionalized hyaluronic acid (HA-CA) hydrogel-encapsulated human mesenchymal stem-cell spheroids (MSC-SPs) could ameliorate damage to the esophagus in a mouse model of radiation-induced esophageal fibrosis. MSC-SPs were cultured in concave microwells 600 μm in diameter at a cell density of 1 × 10⁶ cells per mL. Most cells formed spheroids with a 100-300 μm size distribution in concave microwells. MSC-SPs were well maintained in the HA gel, and live-dead staining confirmed that most cells survived. The HA gel containing the MSC-SPs was then injected into the damaged esophageal layer. Inflammatory signs or adverse tissue reactions were not observed after esophageal injection of HA-gel-encapsulated MSC-SPs. Based on Masson's trichrome staining at 4 and 12 weeks postinjection, the inner esophageal layer (IEL) was significantly thinner in the MSC-SP + HA gel group compared to those in the other experimental groups. While the saline and HA gel treatments made the esophageal muscles loose and thick, the MSC-SP + HA gel group showed bundles of tightly packed esophageal muscles, as assayed by desmin immunostaining. qPCR analysis showed that epithelial genes tended to increase over time in the MSC-SP + HA gel group, and the expression of most fibrosis-related genes decreased. This study proposes the potential of using HA-CA-hydrogel-encapsulated MSC-SPs as a promising therapy against radiation-induced esophageal fibrosis.

Role of concurrent chemoradiation on locally advanced unresectable adenoid cystic carcinoma

BACKGROUND/AIMS

Adenoid cystic carcinoma (ACC) is a rare salivary gland tumor characterized by indolence, with a high rate of local recurrence and distant metastasis. This study aimed to investigate the effect of concurrent chemoradiation (CCRT) on locally advanced unresectable ACC.

METHODS

We retrospectively analyzed clinical data from 10 patients with pathologically confirmed ACC of the head and neck who received CCRT with cisplatin in Seoul National University Hospital between 2013 and 2018.

RESULTS

Ten patients with unresectable disease at the time of diagnosis or with positive margins after surgical resection received CCRT with weekly cisplatin. Eight patients (80%) achieved complete remission, of which three later developed distant metastases without local relapse; one patient developed distant metastasis and local relapse. Two patient achieved partial remission without progression. Patients experienced several toxicities, including dry mouth, radiation dermatitis, nausea, and salivary gland inflammation of mostly grade 1 to 2. Only one patient showed grade 3 oral mucositis. Median relapse-free survival was 34.5 months (95% confidence interval, 22.8 months to not reached).

CONCLUSION

CCRT with cisplatin is effective for local control of ACC with manageable toxicity and may be an effective treatment option for locally advanced unresectable ACC.

Self-crosslinking hyaluronic acid-carboxymethylcellulose hydrogel enhances multilayered 3D-printed construct shape integrity and mechanical stability for soft tissue engineering

One of the primary challenges in extrusion-based 3D bioprinting is the ability to print self-supported multilayered constructs with biocompatible hydrogels. The bioinks should have sufficient post-printing mechanical stability for soft tissue and organ regeneration. Here, we report on the synthesis, characterization and 3D printability of hyaluronic acid (HA)-carboxymethylcellulose (CMC) hydrogels cross-linked through N-acyl-hydrazone bonding. The hydrogel's hydrolytic stability was acquired by the effects of both the prevention of the oxidation of the six-membered rings of HA, and the stabilization of acyl-hydrazone bonds. The shear-thinning and self-healing properties of the hydrogel allowed us to print different 3D constructs (lattice, cubic and tube) of up to 50 layers with superior precision and high post-printing stability without support materials or post-processing depending on their compositions (H7:C3, H5:C5 and H3:C7). Morphological analyses of different zones of the 3D-printed constructs were undertaken for verification of the interconnection of pores. Texture profile analysis (TPA) (hardness (strength), elastic recovery, etc) and cyclic compression studies of the 3D-printed constructs demonstrated exceptional elastic properties and fast recovery after 50% strain, respectively, which have been attributed to the addition of CMC into HA. A model drug quercetin was released in a sustained manner from hydrogels and 3D constructs. In vitro cytotoxicity studies confirmed the excellent cyto-compatibility of these gels. In vivo mice studies prove that these biocompatible hydrogels enhance angiogenesis. The results indicate that controlling the key properties (e.g. self-crosslinking capacity, composition) can lead to the generation of multilayered constructs from 3D-bioprintable HA-CMC hydrogels capable of being leveraged for soft tissue engineering applications.

Predominant DICER1 Pathogenic Variants in Pediatric Follicular Thyroid Carcinomas

Background: Pediatric thyroid cancer has characteristics that are distinct from adulthood thyroid cancer. Due to its very low prevalence, little is known about the genetic characteristics of pediatric follicular thyroid cancer (FTC). Methods: We investigated genetic alterations in tumor tissues from 15 patients aged <20 years (median: 14.3 years; range: 2.4 - 19.0 years) using multifaceted approaches. Whole-exome sequencing, targeted next-generation sequencing using a cancer gene panel, and Sanger sequencing of the major exons of the H/K/N-RAS and DICER1 genes and the promoter region of the TERT gene were performed. Normal tissues or blood of patients with DICER1- or PTEN-positive tumors was also evaluated to determine whether the variant is germ line. Results: The median tumor size was 3.1 cm (range: 0.6 - 6.4 cm). Four patients exhibited angioinvasion and one extensive capsular invasion; none showed evidence of disease over a median of 8.1 years. Eight patients (53.3%) had DICER1 variants, including four with DICER1 syndrome (three patients were <10 years of age). One patient had a germ line PTEN frameshift variant with the diagnosis of PTEN hamartoma tumor syndrome. One patient had a PAX8/PPARγ rearrangement, and two patients had no genetic driver alteration other than multiple loss of heterozygosity with or without copy number alterations in their tumors. No RAS or TERT variants were found. Nodular hyperplasia and follicular adenoma (FA) coexisted in DICER1 variant-positive FTCs more frequently than variant-negative FTCs (p = 0.026). All DICER1 variant-positive FTCs had a somatic missense variant at metal binding sites (six at codon p.E1813 and two at codon p.D1709) within the RNase IIIb domain; seven had other missense, nonsense, or frameshift variants in the DICER1 gene. Six coexisting FAs of two patients with DICER1 syndrome (three of each) had additional somatic variants at metal binding sites within the RNase IIIb domain (codon p.E1705, p.D1709, p.D1810, or p.E1813), different from each other and from the indexed FTC tumor. Conclusions: Pediatric FTCs have distinct genomic alterations and pathogenesis compared with adults, particularly those characterized by DICER1 variants. The DICER1 variant should be considered in pediatric FTCs, especially in cases <10 years of age. In all DICER1 variant-positive FTCs and FAs, recurrent hotspot variants were found at metal binding sites within the RNase IIIb domain, suggesting they impact tumorigenesis.

OR28-06 Assessment of Long Term Quality of Life According to Treatment Options in Low Risk Papillary Thyroid Microcarcinoma Patients - Active Surveillance or Immediate Surgery, (A Follow up Interim Analysis of Maestro)

Background: The Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) started in June 2016. As a follow-up study of comparing the quality of life (QoL) of the active surveillance (AS) and immediate surgery (OP) groups at 8 months (9.3±4.8 and 7.1±4.2 months, respectively), here we aimed to compare the QoL between the AS and OP groups after 18 months (22.8±4.0 and 22.3±4.3 months, respectively) of follow-up.

Methods: QoL of 108 participants who chose AS, 101 who underwent OP, twelve who changed from AS to OP was evaluated using a thyroid‐specific QoL questionnaire at diagnosis and during follow‐up (median 23 months).

Results: The mean ages of the participants in the AS and OP groups were 47.7±11.0 and 45.1±10.0 years (p=0.075), respectively. At baseline, better physical (8.2±1.4 vs. 7.6±1.8, p=0.032), psychological (7.4±1.2 vs. 6.7±1.6, p=0.010), and total health (7.4±1.0 vs. 6.7±1.3, p=0.005) were observed in the AS group than in the OP group. After a mean follow up of 22.7±4.2 months, better physical (8.1±1.5 vs. 7.4±1.7, p=0.008), psychological (7.7±1.3 vs. 7.0±1.5, p=0.002), and total health (7.5±1.2 vs. 6.8±1.3, p=0.001) were observed in the AS group than in the OP group, whereas spiritual health was comparable between the two groups: compared with the AS group, the OP group experienced more alterations in appetite, sleep, menstrual cycle, voice, motor skill, weight, appearance, cold or heat tolerance, and body swelling. Furthermore, better QOL scores were observed in the AS group in self-concept, personal relationships, sexual life, work motivation, productivity and quality of work, feeling of isolation, driving, doing household chores, preparing meals and doing leisure activities after long term follow up.

Conclusion: Patients who underwent AS had better QOL even after long term follow up. Low risk papillary thyroid microcarcinomas do not influence survival, however surgery related deterioration of QOL lasted long and did not improve even in late post-operative stages when patients were fully recovered from surgery.

Keywords: Quality of life; papillary thyroid microcarcinoma; active surveillance; immediate surgery

Tissue-Engineered Graft for Circumferential Esophageal Reconstruction in Rats

The use of biocompatible materials for circumferential esophageal reconstruction is a technically challenging task in rats and requires an optimal implant technique with nutritional support. Recently, there have been many attempts at esophageal tissue engineering, but the success rate has been limited due to difficulty in early epithelization in the special environment of peristalsis. Here, we developed an artificial esophagus that can improve the regeneration of the esophageal mucosa and muscle layers through a two-layered tubular scaffold, a mesenchymal stem cell-based bioreactor system, and a bypass feeding technique with modified gastrostomy. The scaffold is made of polyurethane (PU) nanofibers in a cylindrical shape with a three-dimensional (3D) printed polycaprolactone strand wrapped around the outer wall. Prior to transplantation, human-derived mesenchymal stem cells were seeded into the lumen of the scaffold, and bioreactor cultivation was performed to enhance cellular reactivity. We improved the graft survival rate by applying surgical anastomosis and covering the implanted prosthesis with a thyroid gland flap, followed by temporary nonoral gastrostomy feeding. These grafts were able to recapitulate the findings of initial epithelialization and muscle regeneration around the implanted sites, as demonstrated by histological analysis. In addition, increased elastin fibers and neovascularization were observed in the periphery of the graft. Therefore, this model presents a potential new technique for circumferential esophageal reconstruction.

Poor prognostic factors in human papillomavirus-positive head and neck cancer: who might not be candidates for de-escalation treatment?

BACKGROUND/AIMS

Since patients with human papillomavirus (HPV)-associated head and neck squamous cell carcinoma (HNSCC) have favorable outcomes after treatment, treatment de-escalation for these patients is being actively investigated. However, not all HPV-positive HNSCCs are curable, and some patients have a poor prognosis. The purpose of this study was to identify poor prognostic factors in patients with HPV-positive HNSCC.

METHODS

Patients who received a diagnosis of HNSCC and tested positive for HPV from 2000 to 2015 at a single hospital site (n = 152) were included in this retrospective analysis. HPV typing was conducted using the HPV DNA chip assay or liquid bead microarray system. Expression of p16 in the tumors was assessed by immunohistochemistry. To determine candidate factors associated with overall survival (OS), univariate and multivariable Cox regression analyses were performed.

RESULTS

A total of 152 patients with HPV-positive HNSCC were included in this study; 82.2% were male, 43.4% were current or former smokers, and 84.2% had oropharyngeal cancer. By univariate analysis, old age, performance status ≥ 1, non-oropharyngeal location, advanced T classification (T3-4), and HPV genotype 18 were significantly associated with poor OS. By multivariable analysis, performance status ≥ 1 and non-oropharyngeal location were independently associated with shorter OS (hazard ratio [HR], 4.36, p = 0.015; HR, 11.83, p = 0.002, respectively). Furthermore, HPV genotype 18 positivity was also an independent poor prognostic factor of OS (HR, 10.87, p < 0.001).

CONCLUSION

Non-oropharyngeal cancer, poor performance status, and HPV genotype 18 were independent poor prognostic factors in patients with HPV-positive HNSCC. Patients with these risk factors might not be candidates for de-escalation treatment.

Clinical outcomes and prognostic factor analysis after salvage surgery for recurrent squamous cell carcinoma of the oral cavity

The purpose of this study was to analyze the oncological outcomes and predictive factors for successful curative salvage surgery after recurrent oral cavity squamous cell carcinoma. A retrospective study was conducted involving 73 patients who received surgery-based salvage treatment. The pattern of failure for primary treatment was local failure in 29 patients, regional failure in 29 patients, and loco-regional failure in 15 patients. The 5-year overall, loco-regional failure-free, and disease-free survival rates were 54.8%, 58.9% and 49.3%, respectively. Patients with an advanced initial N stage, previous treatment with combined modality therapy, loco-regional recurrence, advanced recurrent T stage, a disease-free survival of less than 8 months prior to salvage, and recurrence in a previously treated field had a significantly worse prognosis. Given the potential surgical morbidity, salvage surgery should be undertaken after careful consultation with patients who have factors for a poor prognosis.

Lung metastasis in adenoid cystic carcinoma of the head and neck

BACKGROUND

Distant metastasis of adenoid cystic carcinoma (ACC) is most commonly identified in the lung, but risk factors are still on debate.

METHODS

Risk factors for lung metastasis were evaluated by using Cox proportional hazards model and Kaplan-Meier curves.

RESULTS

Of 112 patients, 48% had distant metastasis; 94.4% of whom had lung metastasis. Univariable analysis revealed sublingual or minor salivary gland, tumor size ≥2.5 cm, and perineural invasion as risk factors (hazard ratio [HR]: 1.99 [1.02-3.91], 2.57 [1.19-5.58], and 2.46 [1.28-4.74], respectively), whereas size, perineural invasion, and local recurrence were risk factors in multivariable analysis (HR: 2.29 [1.05-4.96], 2.32 [1.09-4.96], and 2.68 [1.24-5.79], respectively).

CONCLUSION

Sublingual gland or minor salivary glands ACC has a higher risk of lung metastasis. If the site is not considered, the following factors increased the risk of lung metastasis; (a) size ≥2.5 cm, (b) perineural invasion, and (c) local recurrence.

Longitudinal Assessment of Quality of Life According to Treatment Options in Low-Risk Papillary Thyroid Microcarcinoma Patients: Active Surveillance or Immediate Surgery (Interim Analysis of MAeSTro)

Background: In this ongoing multicenter prospective cohort study on active surveillance (AS) in low-risk papillary thyroid microcarcinoma (PTMC), we aimed to compare the quality of life (QoL) of participants based on their choice of treatment, that is, AS or immediate surgery (OP). Methods: QoL of 203 participants who chose AS and 192 participants who underwent OP was evaluated using a thyroid-specific QoL questionnaire at diagnosis and during follow-up (median 8 months). Results: The mean ages of the participants in the AS and OP groups were 47.3 ± 11.7 and 45.6 ± 10.5 years (p = 0.138), respectively, and the mean tumor sizes were 5.7 ± 1.6 and 6.5 ± 2.1 mm (p = 0.065), respectively. At baseline, significantly better psychological health (7.1 ± 1.3 vs. 6.8 ± 1.6, p = 0.023) and overall health (6.8 ± 1.2 vs. 6.5 ± 1.3, p = 0.018) were observed in the AS group than in the OP group. During follow-up, significantly better physical (7.9 ± 1.1 vs. 7.4 ± 1.2, p < 0.001), psychological (7.4 ± 1.3 vs. 6.9 ± 1.6, p = 0.004), and overall health (6.9 ± 1.0 vs. 6.5 ± 1.1, p = 0.002) were observed in the AS group than in the OP group, whereas spiritual health was comparable between the two groups. Compared with the AS group, the OP group experienced more fatigue, changes in voice and appearance, less satisfaction, and low fear of recurrence. The self-assessed financial burden was similar at baseline and follow-up in both groups. Conclusion: The QoL of PTMC patients is different according to the type of treatment. Better psychological health at baseline and physical and psychological health at follow-up were observed in the AS group than in the OP group. However, studies with longer follow-up periods are needed.

Mechanical stimuli enhance simultaneous differentiation into oesophageal cell lineages in a double-layered tubular scaffold

The tissue-engineered oesophagus serves as an alternative and promising therapeutic approach for long-gap oesophageal replacement. This study proposes an advanced in vitro culture platform focused on construction of the oesophagus by combining an electrospun double-layered tubular scaffold, stem cells, biochemical reagents, and biomechanical factors. Human mesenchymal stem cells were seeded onto the inner and outer surfaces of the scaffold. Mechanical stimuli were applied with a hollow organ bioreactor along with different biochemical reagents inside and outside of the scaffold. Electrospun fibres in a tubular scaffold were found to be randomly and circumferentially oriented for the inner and outer surfaces, respectively. Amongst the two types of mechanical stimuli, the intermittent shear flow that can simultaneously cause circumferential stretching due to hydrostatic pressure, and shear stress caused by flow on the inner surface, was found to be more effective for simultaneous differentiation into epithelial and muscle lineage than steady shear flow. Under these conditions, the expression of epithelial markers on the inner surface was significantly observed, although it was minimal on the outer surface. Muscle differentiation showed the opposite expression pattern. Meanwhile, the mechanical tests showed that the strength of the scaffold was improved after incubation for 14 days. We have developed a potential platform for tissue-engineered oesophagus construction. Specifically, simultaneous differentiation into epithelial and muscle lineages can be achieved by utilizing the double-layered scaffold and appropriate mechanical stimulation.

Prognostic value of the association between MHC class I downregulation and PD-L1 upregulation in head and neck squamous cell carcinoma patients

The purpose of this study was to evaluate the prognostic impact of major histocompatibility complex (MHC) class I expression and programmed death-ligand 1 (PD-L1) expression in patients with head and neck squamous cell carcinoma (HNSCC). A total of 158 patients with HNSCC were evaluated retrospectively. The expression of MHC class I and PD-L1 was analyzed in tumor specimens using immunohistochemistry. The association between MHC class I/PD-L1 expression and clinical outcome was evaluated by Kaplan-Meier and Cox regression analyses. Among 158 patients, 103 (65.2%) showed positive PD-L1 expression, and 20 (12.7%) showed no detectable expression of MHC class I. The frequency of PD-L1 positive expression with concomitant MHC class I loss was 7.0%. In the PD-L1-positive group, MHC class I loss was associated with a significantly worse survival compared with MHC class I positivity (median overall survival 39.3 months vs. not reached; P = 0.005), whereas MHC class I status provided no prognostic impact in the PD-L1 negative group. Neither PD-L1 nor MHC class I alone showed a significant difference in overall survival. The loss of MHC class I expression in PD-L1-positive HNSCC was associated with a poor clinical outcome. This suggested that MHC class I expression status might be useful for the prognosis of tumor progression in HNSCC when combined with PD-L1 expression status. External validation with enough numbers of participants in such subgroup should be needed for validation.

A Phase II Study of Genexol-PM and Cisplatin as Induction Chemotherapy in Locally Advanced Head and Neck Squamous Cell Carcinoma

Lessons Learned.

Induction chemotherapy with Genexol‐PM and cisplatin demonstrated modest tumor response in locally advanced head and neck squamous cell carcinoma.

Considering favorable toxicity profiles and promising survival data, further studies on this regimen are warranted in patients with head and neck squamous cell carcinoma.

Background.

Genexol‐PM is a polymeric micellar formulation of paclitaxel without Cremophor EL. We investigated the efficacy and safety of Genexol‐PM plus cisplatin as induction chemotherapy (IC) in patients with locally advanced head and neck squamous cell carcinoma (LA‐HNSCC).

Methods.

Patients received Genexol‐PM (230 mg/m²) and cisplatin (60 mg/m²) every 3 weeks as IC. After three cycles of IC, definitive treatment of either concurrent chemoradiotherapy (CCRT) with weekly cisplatin (30 mg/m²) or surgery was performed. The primary endpoint was overall response rate (ORR) after IC.

Results.

Of 52 patients enrolled, 47 completed three cycles of IC, and the ORR was 55.8% (95% confidence interval, 42.3–69.3). Although there was one treatment‐related death, toxicity profiles to Genexol‐PM and cisplatin were generally favorable, and the most common grade 3 or 4 toxicities were neutropenia (15.4%), anorexia (7.7%), and general weakness (7.7%). Fifty‐one patients received definitive treatment (CCRT [n = 44] or radical surgery [n = 7]). The rate of complete response following CCRT was 81.8% (36/44). After a median follow‐up of 39 months, estimates of progression‐free survival (PFS) and overall survival (OS) at 3 years were 54.3% and 71.3%, respectively.

Conclusion.

IC with Genexol‐PM and cisplatin demonstrated modest tumor response with well‐tolerated toxicity profiles for patients with LA‐HNSCC.

Long-term oncological and functional outcomes of induction chemotherapy followed by (chemo)radiotherapy vs definitive chemoradiotherapy vs surgery-based therapy in locally advanced stage III/IV hypopharyngeal cancer: Multicenter review of 266 cases

OBJECTIVE

The aim of this study was to evaluate the treatment outcomes for stage III/IV locally advanced hypopharyngeal squamous cell carcinoma (SCC), comparing induction chemotherapy followed by (chemo)radiotherapy (ICT), definitive chemoradiotherapy (CRT) and surgery-based therapy (SRT).

SUBJECTS AND METHODS

Two hundred sixty-six patients with stage III/IV locally advanced hypopharyngeal squamous cell carcinoma (SCC) who underwent ICT (n = 74), CRT (n = 53) or SRT (n = 139) from 1997 through 2014 at the Seoul National University Hospital (n = 127) and the Hallym University Medical Center (n = 139) were enrolled in the study. All surgical procedures in the SRT group were performed by a single surgeon to eliminate surgeon bias.

RESULTS

The 5-year disease-free survival (DFS) and overall survival (OS) of all patients (n = 266) were 59.4% and 44%, respectively. The 5-year DFS rates after salvage treatment were 52.7% for ICT, 52.8% for CRT and 65.5% for SRT (p = 0.194). The OS rates were 44.6% for ICT, 39.6% for CRT and 45.3% for SRT group (p = 0.106). The salvage rates were 12.5% for ICT, 15.6% for CRT and 3.8% for SRT group. The final laryngeal preservation rate was significantly lower in the SRT group (44.6%) than in the ICT (71.6%) or CRT (71.7%) groups. All major postoperative complications were significantly higher in the salvage surgery group.

CONCLUSION

Treatment outcomes in the ICT and CRT groups were comparable to that of the SRT group for stage III/IV hypopharyngeal SCC. However, the relatively low chance of cure and high risk of complications should be taken into account when considering salvage surgery.

Comparative studies on thin polycaprolactone-tricalcium phosphate composite scaffolds and its interaction with mesenchymal stem cells

Background

Hybrid scaffolds combining biodegradable polymers and ceramic particles for control of cell adhesion and proliferation are interesting materials for tissue engineering applications. Combinations of biodegradable polymers and ceramics are to provide higher beneficial functionalities to tissue engineering scaffolds with addition of different cell specific bio-factors. Many such hybrid combinations have been reported by several researchers around the world by using various methods and solvents as well as bioactive matrix polymers to fabricate such biomaterials. However, thin hybrid scaffolds with high porosity, cell adhesion factors and biodegradability, as well as the ability to support stem cells often require tedious processes like electrospinning, freeze drying, etc. A simple method to develop porous biodegradable hybrid scaffolds with proper cell adhesion factors is still the need of the hour in tissue engineering and regenerative medicine.

Method

Thin biodegradable poly(ε-caprolactone) (PCL) based hybrid scaffolds were developed in combination with α-tricalcium phosphate (TCP) particles, gelatin and fibronectin separately and the fabricated scaffolds were evaluated systematically using human mesenchymal stem cells (hMSCs) for tissue engineering applications. A simple modified solvent casting method combined with gas foaming process was used to develop porous thin hybrid structures and compared their properties with those of corresponding non-porous hybrid scaffolds. The TCP particles distribution, morphology, biodegradability and functional groups of the different hybrid scaffolds were analyzed using energy-dispersive X-ray spectroscopy (EDX), light microscopy/scanning electron microscopy (SEM), buffer solutions and Fourier-transform infrared spectroscopy (FTIR), respectively The cellular and tissue regeneration behaviors such as in vitro cell attachment (live/dead assay), cell proliferation (CCK-8 assay) and histological studies were performed using hMSCs.

Results

Thin PCL-based hybrid scaffolds were fabricated using modified solvent casting method. Homogeneous distribution of TCP particles in the scaffolds were confirmed by EDX. Cellular interactions of the hybrid scaffolds demonstrated overall higher cell adhesion, proliferation and tissue regeneration on the non-porous thin films of PCL-TCP, PCL-TCP-gelatin and PCL-TCP-fibronectin. Coating of fibronectin was remarkable in induction of cell adhesion and proliferation.

Conclusions

The experimental results revealed that diversely designed PCL-TCP thin hybrid films showed high cell interaction and proliferation with hMSCs. From the results of the cell viability, attachment, proliferation and histological analyses as well as their biodegradation and coating effects, we conclude that these thin PCL-TCP hybrid films are suitable for tissue engineering applications.

Diagnostic value of computed tomography combined with ultrasonography in detecting cervical recurrence in patients with thyroid cancer

BACKGROUND

To determine the diagnostic role of CT added to ultrasound for the diagnosis of recurrent differentiated thyroid cancer (DTC) and to evaluate potential benefits for patients.

METHODS

A total of 193 patients with recurrent DTC were retrospectively included. The diagnostic performances of ultrasound and combination of ultrasound and CT (ultrasound/CT) in detecting recurrence were compared. Benefits of CT were assessed based on the presence of any recurrence detected only with additional CT.

RESULTS

In detecting cervical recurrence, ultrasound/CT showed higher sensitivity (P = .001) and lower specificity (P < .001) than ultrasound alone, overall resulting in higher area under the curve (P < .001). Seventy-nine patients (40.9%) benefited from additional CT in detecting recurrence.

CONCLUSION

For reoperation of cervical recurrence in patients with DTC, addition of CT to ultrasound offers better surgical planning by enhancing detection of recurrent cancers that were overlooked with ultrasound alone.

Persistent/Recurrent Differentiated Thyroid Cancer: Clinical and Radiological Characteristics of Persistent Disease and Clinical Recurrence Based on Computed Tomography Analysis

BACKGROUND

The natural course of persistent/recurrent differentiated thyroid cancer (DTC) has not been fully elucidated. The purpose of this study was to assess the relative incidence and clinico-radiological characteristics of persistent disease and clinical recurrence based on computed tomography (CT) analysis in patients with persistent/recurrent DTC.

METHODS

From January 2005 to December 2016, this retrospective study included 107 patients (M:F = 28:79; M_age = 53.5 years) with surgically proven cervical locoregional recurrence of DTC. Two neck CT examinations (median interval 1.92 years; range 0.17-7.58 years) before the last thyroid cancer surgery within the study period were reevaluated. Based on the presence of the lesion on the first CT and its progression on the second CT, the locoregional recurrence was classified into the following categories: stable persistence (decrease, no change, or increase by <2 mm in short dimension on the second CT), progressive persistence (increase by ≥2 mm), and clinical recurrence (newly appeared on the second CT). Clinical and radiological characteristics of the three groups were compared using univariate and multivariate logistic regression analyses.

RESULTS

The relative incidences of stable persistence, progressive persistence, and clinical recurrence were 56.1% (60/107), 15.0% (16/107), and 29.0% (31/107), respectively. Multivariate analysis between the clinical recurrence (29.0%) and persistence (71.0%) groups revealed various independent factors for prediction of clinical recurrence. These included longer interval between the two CT examinations (median 2.67 vs. 1.79 years; p = 0.021), a smaller number of thyroid surgeries (1.16 ± 0.45 vs. 1.55 ± 0.81; p = 0.002), and a history of neck dissection at the location of the largest locoregional recurrence (70.0% vs. 31.4%; p < 0.001). There was no significant independent factor for differentiation between the stable persistence (78.9%; 60/76) and progressive persistence (21.1%; 16/76) groups. The results may have been influenced by selection bias because this study included only surgically proven cases.

CONCLUSIONS

With regard to cervical locoregional recurrence of DTC, active surveillance may be favored because more than a half of the cases are structurally persistent and stable. However, meticulous evaluation is necessary to detect progressive persistence and clinical recurrence, considering various clinical factors.