Differentiating BRAF V600E- and RAS-like alterations in encapsulated follicular patterned tumors through histologic features: a validation study.

Differentiating BRAF V600E- and RAS-altered encapsulated follicular-patterned thyroid tumors based on morphology remains challenging. This study aimed to validate an 8-score scale nuclear scoring system and investigate the importance of nuclear pseudoinclusions (NPIs) in aiding this differentiation. A cohort of 44 encapsulated follicular-patterned tumors with varying degrees of nuclear atypia and confirmed BRAF V600E or RAS alterations was studied. Nuclear parameters (area, diameter, and optical density) were analyzed using a deep learning model. Twelve pathologists from eight Asian countries visually assessed 22 cases after excluding the cases with any papillae. Eight nuclear features were applied, yielding a semi-quantitative score from 0 to 24. A threshold score of 14 was used to distinguish between RAS- and BRAF V600E-altered tumors. BRAF V600E-altered tumors typically demonstrated higher nuclear scores and notable morphometric alterations. Specifically, the nuclear area and diameter were significantly larger, and nuclear optical density was much lower compared to RAS-altered tumors. Observer accuracy varied, with two pathologists correctly identifying genotype of all cases. Observers were categorized into proficiency groups, with the highest group maintaining consistent accuracy across both evaluation methods. The lower group showed a significant improvement in accuracy upon utilizing the 8-score scale nuclear scoring system, with notably increased sensitivity and negative predictive value in BRAF V600E tumor detection. BRAF V600E-altered tumors had higher median total nuclear scores. Detailed reevaluation revealed NPIs in all BRAF V600E-altered cases, but in only 2 of 14 RAS-altered cases. These results could significantly assist pathologists, particularly those not specializing in thyroid pathology, in making a more accurate diagnosis.

High 4-1BB Expression in PBMCs and Tumor Infiltrating Lymphocytes (TILs) in Patients with Head and Neck Squamous Cell Carcinoma.

OBJECTIVE: 4-1BB is a costimulatory immune-activating molecule. Increased amounts of this protein have previously been found in the plasma of patients with oropharyngeal and oral cancer. Here, we focused on this molecule that functions as part of the immune system. We investigated 4-1BB in the peripheral blood mononuclear cells (PBMCs) and tumor infiltrating lymphocytes (TILs) of patients with head and neck squamous cell cancer (HNSCC). MATERIALS AND METHODS: The expression level of 4-1BB in the PBMCs was determined using real-time polymerase chain reaction (PCR). The TIMER (Tumor Immune Estimation Resource) web server was utilized to approximate the 4-1BB level in HNSCC TILs. Moreover, 4-1BB immunohistochemistry (IHC) was used to validate TILs in four organs of HNSCC, including oral cancer (OC), oropharyngeal cancer (OPC), sinonasal cancer (SNC), and laryngeal cancer (LC), in both the tumor area and adjacent normal epithelium. The difference in 4-1BB expression levels in various groups was assessed using a Kruskal-Wallis test and an independent sample t-test. RESULTS: The level of 4-1BB expression in PBMCs was highest in OPC, followed by OC and healthy controls (HC). Significant differences were discovered between HC and OPC and between OC and OPC. Bioinformatics revealed a substantial correlation between 4-1BB expression level and lymphocyte infiltration in HNSCC, including B cells, CD8+ T cells, and CD4+ T cells. IHC validation in HNSCC tissue revealed that the average number of 4-1BB positive TILs in all four HNSCC subtypes was considerably greater than the number of lymphocytes seen in adjacent normal tissue. Interestingly, the number of lymphocytes that were 4-1BB positive increased in relation to the TIL level. CONCLUSION: A higher number of 4-1BB expression levels were found in the PBMCs and TILs of HNSCC patients, implying that 4-1BB may be a promising approach for HNSCC patients to improve their immune function. It is important to study and create a treatment that uses 4-1BB medicine as well as existing drugs.

Protein expression analysis for predicting recurrent laryngeal squamous cell carcinoma.

The expression of a number of proteins plays a major role in predicting recurrent laryngeal squamous cell carcinoma (LSCC). Thus, the aim of the present study was to investigate the expression of 16 selected proteins as prognostic indicators for recurrent and non-recurrent LSCC. Samples from a total of 41 patients with LSCC were investigated by immunohistochemistry. Digital image analysis was performed, and various associated factors were calculated. Histoscore (H-score) and receiver operating characteristic curves were used to divide protein expression in high and low for predicting disease recurrence. Disease-free survival (DFS) curves, crude hazard ratios (HRs) and adjusted HRs were analyzed and compared. Significantly different H-scores were found between the recurrent and non-recurrent groups in terms of pRb and c-Met expression. pRb was expressed at high levels in recurrent LSCC, while c-Met was expressed at low levels. Patients with low pRb expression had a longer DFS than those with high pRb expression (log-rank χ2, 5.161; P=0.023). Patients with high c-Met expression had a longer DFS than those with low c-Met expression (log-rank χ2, 6.441; P=0.011). Moreover, patients with high pRb expression and low c-Met expression had the shortest DFS (log-rank χ2, 11.827; P=0.008). Differentiated histological factors had an impact on the risk of recurrence (Cox regression test; crude HR, 9.53; 95% confidence interval, 1.214-74.819; P=0.032). The present study demonstrated that the grading of differentiated squamous cell carcinoma, pRb and c-Met expression are the most useful prognostic factors for the prediction of recurrent LSCC. These might be further applied as potential markers for clinical use.

The Asian Thyroid Working Group, from 2017 to 2023.

The Asian Thyroid Working Group was founded in 2017 at the 12th Asia Oceania Thyroid Association (AOTA) Congress in Busan, Korea. This group activity aims to characterize Asian thyroid nodule practice and establish strict diagnostic criteria for thyroid carcinomas, a reporting system for thyroid fine needle aspiration cytology without the aid of gene panel tests, and new clinical guidelines appropriate to conservative Asian thyroid nodule practice based on scientific evidence obtained from Asian patient cohorts. Asian thyroid nodule practice is usually designed for patient-centered clinical practice, which is based on the Hippocratic Oath, "First do not harm patients," and an oriental filial piety "Do not harm one's own body because it is a precious gift from parents," which is remote from defensive medical practice in the West where physicians, including pathologists, suffer from severe malpractice climate. Furthermore, Asian practice emphasizes the importance of resource management in navigating the overdiagnosis of low-risk thyroid carcinomas. This article summarizes the Asian Thyroid Working Group activities in the past 7 years, from 2017 to 2023, highlighting the diversity of thyroid nodule practice between Asia and the West and the background reasons why Asian clinicians and pathologists modified Western systems significantly.

Constitutive Cytomorphologic Features of Medullary Thyroid Carcinoma Using Different Staining Methods.

(1) Background: Accurate preoperative identification of medullary thyroid carcinoma (MTC) is challenging due to a spectrum of cytomorphologic features. However, there is a scarcity of studies describing the cytomorphologic features as seen on fine-needle aspiration (FNA) smears prepared using different staining methods. (2) Methods: We performed a retrospective study on MTC cases with available FNA slides from 13 hospitals distributed across 8 Asia-Pacific countries. The differences in the constitutive cytomorphologic features of MTC with each cytopreparatory method were recorded. A comparative analysis of cytologic characteristics was carried out with appropriate statistical tests. (3) Results: Of a total of 167 MTC samples retrospectively recruited, 148 (88.6%) were interpreted as MTC/suspicious for MTC (S-MTC). The staining methods used were Papanicolaou, hematoxylin-eosin, and Romanowsky stains. Seven out of the eleven cytologic criteria can be readily recognized by all three cytopreparatory methods: high cellularity, cellular pleomorphism, plasmacytoid cells, round cells, dyshesive cells, salt-and-pepper chromatin, and binucleation or multinucleation. An accurate diagnosis was achieved in 125 (84.5%) of the 148 samples whose FNAs exhibited five or more atypical features. Conclusions: The present work is the first study on MTC to compare the morphological differences among the cytologic staining techniques. We investigated the constitutive features and the reliability of diagnostic parameters. A feasible scoring system based upon cytomorphologic data alone is proposed to achieve a high degree of diagnostic accuracy.

MCM-2, Ki-67, and EGFR downregulated expression levels in advanced stage laryngeal squamous cell carcinoma.

We present the conceptual study investigated the capacity of minichromosome maintenance-2 (MCM-2), Ki-67, and epidermal growth factor receptor (EGFR) to assess the severity and progression of laryngeal squamous cell carcinoma (LSCC) disease and to study the correlations among these markers. A total of 30 patients with LSCC with immunohistochemistry (IHC) staining for MCM-2, Ki-67 and EGFR were examined. Mean expression levels of the three markers were evaluated for comparing between early and advanced stages of LSCC. The mean MCM-2, Ki-67, and EGFR expression levels were significantly decreased in advanced-stage compared with early-stage LSCC. Pearson correlation analysis showed a statistically significant correlation between the MCM-2 and Ki-67. Regarding subgroup analyses, MCM-2, Ki-67, and EGFR showed significant differences between early- and advanced-stage LSCC with non-recurrence, while for the recurrent subgroup LSCC, only MCM-2 revealed a significant difference between early- and advanced-stage LSCC. Altogether, these results support the role for downregulation of MCM-2, Ki-67 and EGFR in advanced-stage LSCC and correlation of MCM-2 and Ki-67 expressions that would be a promising strategy to predict prognosis of LSCC including severity and progression. We contextualize our findings and advocate the position of the biological markers, especially MCM-2, as an emerging evaluation tool for LSCC disease.

The effects of whole-body vibration on wound healing in a mouse pressure ulcer model.

BACKGROUND: Pressure ulcers are one of the most common complications of immobility resulting from pressure and shear. Whole-body vibration (WBV) has been shown to increase skin blood flow but little information is known about its effect on pressure ulcers. This study investigated the effects of WBV on wound healing in a mouse pressure ulcer model. METHODS: Two cycles of ischemia-reperfusion were performed by external application of two magnetic plates to dorsal skin to induce stage II pressure ulcers characterized by partial-thickness skin loss with exposed dermis. A total of 32 male ICR mice were randomly and equally divided into untreated control and the WBV groups. Immediately after the completion of 2-cycle ischemia-reperfusion injury, mice in the WBV group participated in a WBV program using a vibrator (frequency 45 Hz, peak acceleration 0.4 g, vertical motion) for 30 min/day and 5 consecutive days/week. At days 7 and 14 post-ulceration, wound closure rate was assessed. Wound tissues were harvested for determination of collagen deposition in Masson's trichrome stained sections, neutrophil infiltration and capillary density in hematoxylin and eosin-stained sections, as well as TNF-α and VEGF levels using ELISA. RESULTS: TNF-α levels and neutrophil infiltration were significantly decreased in wounds on days 7 and 14 of WBV treatment. Moreover, wound closure rate and collagen deposition were remarkably accelerated on day 14. Tissue VEGF and capillary density were unaffected by WBV at either time point. CONCLUSIONS: These findings suggest that WBV has the potential to promote the healing process of stage II pressure ulcers, as evidenced by attenuation of wound inflammation and enhancement collagen deposition.

Molecular Correlates and Nuclear Features of Encapsulated Follicular-Patterned Thyroid Neoplasms.

BACKGROUND: Assessing nuclear features is diagnostically challenging in the aspect of thyroid pathology. The aim of this study was to determine whether pathologists could distinguish BRAF-like and RAS-like nuclear features morphologically and identify morphological features to differentiate thyroid tumors with RAS-like mutations from encapsulated papillary thyroid carcinoma (PTC) with predominant follicular growth and BRAFV600E mutation. METHODS: Representative whole slide images of 16 encapsulated thyroid tumors with predominant follicular growth were reviewed by 12 thyroid pathologists using a web browser-based image viewer. Total nuclear score was calculated from semi-quantitatively scored eight nuclear features. The molecular profile of RAS and BRAF genes was determined by Sanger sequencing. RESULTS: Total nuclear score ranging 0 to 24 could differentiate BRAF-like tumors from RAS-like tumors with a cut-off value of score 14. The interobserver agreement was the highest for the assessment of nuclear pseudoinclusions (NPIs) but the lowest for nuclear elongation and sickle-shaped nuclei. NPIs were found in tumors with BRAFV600E mutation, but not in tumors with RAS-like mutations. Total nuclear scores were significantly higher for tumors with BRAFV600E than for those with RAS-like mutations (P<0.001). CONCLUSION: Our results suggest that NPIs and high nuclear scores have diagnostic utility as rule-in markers for differentiating PTC with BRAFV600E mutation from benign or borderline follicular tumors with RAS-like mutations. Relaxation of rigid criteria for nuclear features resulted in an overdiagnosis of PTC. Immunostaining or molecular testing for BRAFV600E mutation is a useful adjunct for cases with high nuclear scores to identify true PTC.

Cytologic diagnosis of medullary thyroid carcinoma in the Asia-Pacific region.

BACKGROUND: The accurate preoperative identification of medullary thyroid carcinoma (MTC) is challenging due to the rarity of tumor and variable cytologic appearance. The Asian experience with diagnosing MTC by fine-needle aspiration (FNA) was scarcely reported. METHODS: Cases of MTC with available FNA slides were enrolled from 13 hospitals representing 8 Asia-Pacific countries. Clinicopathological information, including sample preparation technique, staining method, original cytologic diagnosis and review diagnosis were collected. RESULTS: Of a total of 145 MTC cases retrospectively recruited, 99 (68.3%) were initially interpreted as MTC/suspicious for MTC (S-MTC). The distribution of original FNA diagnostic categories was not associated with the staining method or sample preparation technique. The staining methods used were Papanicolaou, hematoxylin-eosin and Romanowsky stains. Liquid-based cytology (LBC) was used only in three countries. After reviewing all cases, the diagnostic rate of MTC/S-MTC increased to 91.7% (133/145). Cases with initially unrecognized MTC had either marked pleomorphism or cytology mimicking papillary carcinoma or follicular neoplasm. Although LBC provided certain benefits, there was no significant difference in diagnostic accuracy between conventional smear and LBC. Immunocytochemistry was available in 38 cases (26.2%), all of which were correctly recognized as MTC. CONCLUSION: Our report summarizes how MTC is handled in contemporary Asian thyroid FNA practice. Although the detection rate of MTC by cytology alone is less satisfactory, integration with ancillary tests could achieve an excellent performance. The recognition of constitutive cytomorphologic features is needed for each cytopreparatory method, which may result in a lower threshold to initiate further workup for MTC.

Epstein-Barr Virus-Associated Langerhans Cell Histiocytosis of the Thyroid Gland.

Thyroid gland involvement of Langerhans cell histiocytosis (LCH) is extremely rare in both systemic and isolated disease. The role of viral infection in LCH development is not yet fully understood. Although several viruses are proposed as etiologic factors, such as Epstein-Barr virus (EBV) and human herpesvirus 6 (HHV-6), they seem to play a bystander role in LCH. A 29-year old female patient with a prior history of multisystemic LCH (pituitary gland and skull bone), presented with a thyroid nodule. The patient underwent a total thyroidectomy and the histological examination revealed nodular lesions composed of sheets and clusters of histiocytes in the inflammatory background. The histiocytes stained positive for S-100 and CD1a and were negative for HHV-8, cytomegalovirus, and VE1 (anti-BRAFV600E) on immunohistochemistry. The EBER in situ hybridization for EBV showed frequent positive-stained cells. The conventional PCR analysis for EBV was positive and qPCR analysis confirmed a significant DNA copy number difference (p = 0.02) between the tumor and adjacent non-neoplastic thyroid tissue. PCR analysis for HHV-6, HPV, HSV was negative in both tumor and benign samples. In conclusion, the presented case showed a rare thyroid involvement by LCH associated with EBV infection, which has not been reported before. Further studies are required to investigate a possible etiologic link between EBV infection and LCH.

Clinical association of CXCR4 in primary tumor of papillary thyroid cancer and response to iodine-131 treatment.

OBJECT: Papillary thyroid cancer (PTC) has an excellent prognosis. However, patients with such, if refract to radioiodine treatment, increase recurrent and mortality rates. Tumor aggressiveness in primary tumor of PTC expresses CXCR4 chemokine receptor. Thus, CXCR4 expression of the tumor may predict response to radioiodine treatment. MATERIALS AND METHODS: Retrospective review of seventy-four PTC patients, treated with total/near-total thyroidectomy and radioiodine treatment at King Chulalongkorn Memorial Hospital from January 2007 to 2013, were classified as non-radioiodine-refractory (non-RAIR) or RAIR treatment response. All histopathologic diagnoses were reviewed and paraffin blocks were retrieved for CXCR4 immunostaining, determined by automated digital imaging analysis for intensity and extension. The scores were compared between primary tumour and adjacent normal thyroid tissue as well as between the tissue of non-RAIR and that of RAIR. Factors determining type of RAI response were analyzed. RESULTS: CXCR4 immunostaining scores of PTC is significantly higher than normal thyroid [2.03 (0.52) and 1.48 (0.75)] [mean (SD)] (P = 0.0001). CXCR4 immunostaining scores in RAIR are potentially higher than non-RAIR [1.95 (0.54) and 2.13 (0.47) (P = 0.149)]. Odds ratio of CXCR4 immunostaining score for predicting RAIR treatment is 1.99 (P = 0.150). CXCR4 immunostaining scores positively associate with tumor size (R = 0.298, P = 0.01); whereas no significant association with other clinicopathologic factors. CONCLUSION: Our data support the notion that CXCR4 are significantly expressed in PTC tumor over normal thyroid tissues. However, there is no clinical association with radioiodine treatment response.

Pathological practice and management of thyroid nodules: a Thai perspective.

Although, in the thyroid field, there have been several internationally standard diagnostic and management guidelines for practitioners from every country to follow but there is still variation among physicians across the globe in taking care of patients and pathology specimens with thyroid nodules due to dissimilar backgrounds of each place. Thailand is one among several countries that tries to maintain standard of care to meet international requirements although, with some limitations, not all recommendations are followed. To understand how approaches of thyroid nodules are performed throughout the country and how the healthcare system of the whole kingdom is managed including what major current limitations, the authors conducted a survey among physicians consisting of surgeons, radiologists and pathologists who are involved in the management of the thyroid lesions by personal phone contact and custom online questionnaires. Performances of fine needle aspiration of different institutes are also evaluated by analyzing the data from available publications and compared their results with other series from the literature. Shortage of pathologists and un-equal resource allocation are the major problems concerning administrative aspect while a lack of awareness in new terminologies or diagnostic systems (e.g., NIFTP, UMP, Bethesda, TI-RADS) among physicians, particularly clinicians, are the problems of training and continuous medical education. Another point of concern is a rather poor performance in fine needle aspiration from the Thai series in which there are high rate (30.5%) of non-diagnostic category (Bethesda I) and false negativity as demonstrated by relatively high risk of malignancy (9.6%) in Bethesda II compared with other series from the literature. Regarding molecular studies, despite their usefulness in improving diagnostic accuracy, especially for cytology specimens, these ancillary tools are not routinely used in our practice since they are available in only few referral centers. This review provided a background information of the perspective on how thyroid nodules are managed in the Thai settings.

An affordable immunohistochemical approach to estimate the prevalence of BRAFV600E in large cohort studies-establishing the baseline rate of BRAF mutation in an institutional series of papillary thyroid carcinoma from Thailand.

BACKGROUND: Papillary thyroid carcinoma (PTC) accounts for the majority of diagnoses of thyroid carcinoma. BRAFV600E mutation is the most common genetic alteration in PTC, which has diagnostic and prognostic significance. The rate of BRAFV600E mutation in PTC from Thailand has not been reported. Our purpose was to estimate the prevalence of BRAF mutation in a large institutional series using an affordable approach, which combined mutation-specific immunohistochemistry (IHC) with VE1 antibody and tissue microarray (TMA). METHODS: A total of 476 PTC cases plotted on TMA were employed for determining the mutation status in this study. The cancer tissue of initial 100 cases (pilot study) were analyzed for BRAFV600E mutation by using both direct sequencing and VE1 immunostaining. For the subsequent PTC cases, VE1 IHC was used as an alternative to direct sequencing for the detection of mutation. Univariate and multivariate analyses were done to determine the association of clinicopathological variables with BRAFV600E mutation. RESULTS: In the pilot study, VE1 IHC showed excellent analytical performance (κ=0.884) for detecting BRAFV600E mutation in PTC TMA as compared to direct sequencing. The prevalence of BRAFV600E in the whole cohort was 60.9% by using VE1 IHC. The mutation was commonly seen in tall cell (92.9%) and classic (70.2%) variants of PTC. Multivariate analysis (P<0.05) showed association of BRAFV600E with histological type of tumor, extrathyroidal extension, and absence of Hashimoto's thyroiditis. CONCLUSIONS: In conclusion, BRAFV600E mutation was detected in 60.9% of Thai PTC and it was associated with several aggressive clinicopathological variables of thyroid cancer. VE1 IHC proved as a reliable method able to replace direct sequencing for detection of the mutation. A combination of mutation-specific IHC and TMA allows conducting large cohort studies more labor-saving and cost-efficiently.

VE1 Immunohistochemistry Improves the Limit of Genotyping for Detecting BRAFV600E Mutation in Papillary Thyroid Cancer.

Detection of BRAFV600E is useful for making diagnosis and risk stratification of papillary thyroid carcinoma (PTC). Molecular testing, however, is not always available for routine clinical use. To assess the clinical utility and reliability of VE1 immunohistochemistry (IHC) for detecting BRAFV600E mutation in PTC, VE1 IHC was performed on the tissue microarrays of 514 patients with PTC and was compared with Sanger sequencing results. Of 514 PTC cases, 433 (84.2%) were positive for VE1 expression. Among 6 discordant cases between VE1 IHC and Sanger sequencing, 3 initial VE1-false negative cases turned out to be true false negative on repeat testing, and 3 VE1-false positive cases showed BRAFV600E mutation using digital PCR analysis. PTCs with low variant allele fraction were positive for VE1 IHC but were not detected using sequencing. VE1 IHC showed 99.3% sensitivity, 100% specificity, 100% positive predictive value, and 96.4% negative predictive value. The BRAFV600E mutation was significantly associated with older age, multifocality, extrathyroidal extension, lymph node metastasis, and advanced tumor stage. In conclusion, VE1 IHC is a reliable method for detecting BRAFV600E mutation in PTC specimens.

EGFR cut-off point for prognostic impact in laryngeal squamous cell carcinoma.

Background: Various molecular biomarkers, including epidermal growth factor receptor (EGFR), have gained importance as predictors of head and neck cancer disease progression.Aims: This study aimed to investigate the ability of EGFR expression as a prognostic marker for laryngeal squamous cell carcinoma (LSCC).Materials and methods: A total of 31 patients with LSCC with immunohistochemistry (IHC) staining for EGFR were examined. Digital image processing was applied to analyze EGFR staining intensity and percent distribution, which were calculated as the H-score. We used a receiver operating characteristic (ROC) curve to identify the best cut-off point of EGFR expression, with H-score separated into high- and low-grade for cancer recurrence prediction.Results: The cut-off point of EGFR expression for high- and low-grades was an H-score of 170 with a sensitivity of 75% and a specificity of 66.7%. Using this cut-off, 14 (45.16%) and 17 (54.84%) patients were categorized as having high- and low-grades EGFR, respectively. The analysis showed a significant reverse correlation between the EGFR grade and LSCC recurrence (RR, 0.4; 95% CI, 0.17-0.98; p = .02).Conclusions: Our study demonstrated that EGFR grading using H-score with the generated cut-off point by the ROC curve might be further applied as a potential marker for LSCC prognostic prediction.

Evaluation of NID2 promoter methylation for screening of Oral squamous cell carcinoma.

BACKGROUND: Oral squamous cell carcinoma (OSCC) is an aggressive human malignancy. Because of late diagnosis and recurrence of OSCC, the treatment of patients with OSCC is often ineffective. Thus, finding novel biomarkers of OSCC are essential. Here we derived a methylation marker by utilizing methylation microarray data and testing its capacity in cross-sectional study designed for OSCC detection and screening. METHODS: According to bioinformatics analysis of total of 27,578 cg sites, cg22881914 of Nidogen 2 (NID2) methylation was selected for evaluation. Next, we confirmed the methylation status by bisulfite sequencing from the microdissected OSCC cells in comparison with the microdissected oral epithelia. Subsequently, we developed a simple technique using real-time PCR with the specific probe to examine the ability for the detection of OSCC in the oral epithelial samples, which included 103 oral rinse and 82 oral swab samples. RESULTS: Based on the comparison of microdissected tissue, cg22881914 of NID2 was proved to be methylated in most OSCC cells but unmethylated in the normal oral epithelia. Furthermore, the methylated NID2-relied quantitative PCR approach has demonstrated that this marker assists in distinguishing among patients with OSCC from normal oral epithelia, smokers, and patients with oral lichen planus using the non-invasive oral rinse and swab samples. CONCLUSIONS: Specific methylation at cg22881914 of NID2 of OSCC could be used as an important potential marker for detecting OSCC. Thus, to certify the utility of this marker, further studies with a larger sample size are needed.

Low prevalence of p16-positive HPV-related head-neck cancers in Thailand: tertiary referral center experience.

BACKGROUND: There has been a sharp rise in the incidence of human papillomavirus (HPV) associated oropharyngeal squamous cell carcinoma (OPSCC) in many countries. Patients with HPV-positive OPSCC have a more favorable prognosis compared with HPV-negative OPSCC, leading to investigation and adoption of de-escalation treatment protocols. The baseline rate of HPV prevalence in certain populations is of epidemiologic significance. We aimed to evaluate the rate of high-risk HPV in a large cohort of Thai patients, including OPSCC, oral SCC (OSCC) and laryngeal SCC (LSCC). METHODS: In total, 504 patients with HN cancer (110 OPSCC, 260 OSCC and 134 LSCC) who had been treated in Chulalongkorn University between 2010 and 2016 formed the sample set. All histological slides were reviewed to validate the diagnosis and render the histological type as keratinizing (K), non-keratinizing (NK) or non-keratinizing with maturation (NK-M). Immunohistochemistry with p16 was performed in all cases and scored semiquantatively. Positive and equivocal cases were tested by the high-risk HPV DNA in situ hybridization (ISH). Validation with quantitative polymerase-chain reaction (qPCR) was performed in p16-positive OPSCC. RESULTS: The OPSCC were represented by NK (7.3%), NK-M (16.4%) and K (76.4%) types, with an HPV incidence of 100, 22.2 and 4.7%, respectively. The average HPV prevalence in OPSCC was 14.5%. The concordance with p16/ISH was 51.6%, while concordance of the NK morphology with positive HPV ISH was 100%. ISH-qPCR concordance in p16-positive OPSCC was 72.7%. Patients with HPV-positive OPSCC had significantly more tumors with a NK histologic type, tonsillar location, earlier clinical stage, less association with smoking, and, finally, better outcome and longer survival time. In non-OPSCC, p16-positive HPV-associated cancers were found in only 1.5% of OSCC (4/260) and LSCC (2/134). CONCLUSION: A low rate of HPV-related OPSCC was found in Thai patients. The NK morphology was an excellent predictor of high-risk HPV infection in OPSCC. For OPSCC patients, HPV-positive ones had a significantly longer survival time than HPV-negative ones. There was a lack of p16-positive HPV-related OSCC and LSCC. Morphology and p16 status had a poor predictive value for detecting HPV in OSCC and LSCC.

Sphenoid Sinus Cholesteatoma-Complications and Skull Base Osteomyelitis: Case Report and Review of Literature.

INTRODUCTION: Cholesteatoma of the paranasal sinuses is uncommon. Its clinical characteristics are an expanding growth of the affected paranasal sinuses consisting of keratinizing squamous epithelium with bony wall destruction. Among involved paranasal sinuses, sphenoid sinus cholesteatoma is the least common. CASE PRESENTATION: An 82-year-old female diabetic patient presented with subacute onset of fever after experiencing chronic progressive headaches for more than 20 years. Nasal endoscopy found purulent discharge from left sphenoethmoidal recess. Computed tomography (CT) scan of the paranasal sinus showed soft tissue lesions that totally filled the left sphenoid sinus with posterior and inferior wall destruction. There was no evidence of connection to the left mastoid cavity. MANAGEMENT AND OUTCOME: Left sphenoidotomy was performed. Histopathology revealed cholesteatoma. Two months after surgery, she became worse and CT showed extensive skull base destruction. The patient underwent bilateral sphenoidectomy and craniotomy with surgical debridement of osteomyelitis of the skull base. She received long-term intravenous ertapenam and sitafloxacin for treating drug-resistant Klebsiella infection. The osteomyelitis could not be controlled, and she died. DISCUSSION: Progressive headache can be caused by an uncommon disease such as sphenoid sinus cholesteatoma, which is a surgical condition. Complicating osteomyelitis of the skull base requires extensive debridement surgery and should be anticipated.

Compact buds with biphasic differentiation and calcitonin-expressing neuroendocrine cells-previously unrecognized structures of thyroglossal duct unveiled by immunohistochemistry.

Immunophenotype of thyroglossal duct (TGD) cysts, including lining epithelium and thyroid remnants, is scarcely addressed in the literature. There is indirect evidence that C cells may be derived from progenitor cells of the midline thyroid primordium. This is supported by the recent concept of the endodermal origin of lateral thyroid anlagen and several case reports. We aimed to search for neuroendocrine cells in TGD cysts and to characterize immunophenotype of the thyroid follicles and epithelial lining of TGD. Out of 98 TGD cysts, 70% contained both cyst-lining epithelium and thyroid follicles, whereas 30% possessed only cyst-lining epithelium. Specimens eligible for immunohistochemistry (n = 61) were stained for thyroid-specific and neuroendocrine markers. Thyroid remnants were positive for thyroid transcription factor 1 (TTF-1) and other thyroid tissue-specific markers and negative for calcitonin. TGD epithelium showed strong p63 positivity. We found that respiratory epithelium in 9.8% of TGDs contained neuroendocrine cells positive for calcitonin, chromogranin A, and synaptophysin but negative for carcinoembryonic antigen. In 44.2% of the cases, we detected compact buds, microscopic structures appearing as nests of epithelial cells with a biphasic population of basal (p63+) and central (TTF-1+) cells. Thyroid remnants in TGD expressed full spectrum of thyroid-specific markers and contained no C cells. Instead, calcitonin-expressing neuroendocrine cells were found among the respiratory epithelium of TGD. These cells can be a potential source of neuroendocrine tumors mimicking medullary carcinoma in median anlage derivatives. We also discovered precursor compact buds with dual immunophenotype and proposed a concept of their morphogenesis.