Single-cell transcriptome analysis reveals TOX as a promoting factor for T cell exhaustion and a predictor for anti-PD-1 responses in human cancer

BACKGROUND: T cells exhibit heterogeneous functional states in the tumor microenvironment. Immune checkpoint inhibitors (ICIs) can reinvigorate only the stem cell-like progenitor exhausted T cells, which suggests that inhibiting the exhaustion progress will improve the efficacy of immunotherapy. Thus, regulatory factors promoting T cell exhaustion could serve as potential targets for delaying the process and improving ICI efficacy. METHODS: We analyzed the single-cell transcriptome data derived from human melanoma and non-small cell lung cancer (NSCLC) samples and classified the tumor-infiltrating (TI) CD8+ T cell population based on PDCD1 (PD-1) levels, i.e., PDCD1-high and PDCD1-low cells. Additionally, we identified differentially expressed genes as candidate factors regulating intra-tumoral T cell exhaustion. The co-expression of candidate genes with immune checkpoint (IC) molecules in the TI CD8+ T cells was confirmed by single-cell trajectory and flow cytometry analyses. The loss-of-function effect of the candidate regulator was examined by a cell-based knockdown assay. The clinical effect of the candidate regulator was evaluated based on the overall survival and anti-PD-1 responses. RESULTS: We retrieved many known factors for regulating T cell exhaustion among the differentially expressed genes between PDCD1-high and PDCD1-low subsets of the TI CD8+ T cells in human melanoma and NSCLC. TOX was the only transcription factor (TF) predicted in both tumor types. TOX levels tend to increase as CD8+ T cells become more exhausted. Flow cytometry analysis revealed a correlation between TOX expression and severity of intra-tumoral T cell exhaustion. TOX knockdown in the human TI CD8+ T cells resulted in downregulation of PD-1, TIM-3, TIGIT, and CTLA-4, which suggests that TOX promotes intra-tumoral T cell exhaustion by upregulating IC proteins in cancer. Finally, the TOX level in the TI T cells was found to be highly predictive of overall survival and anti-PD-1 efficacy in melanoma and NSCLC. CONCLUSIONS: We predicted the regulatory factors involved in T cell exhaustion using single-cell transcriptome profiles of human TI lymphocytes. TOX promoted intra-tumoral CD8+ T cell exhaustion via upregulation of IC molecules. This suggested that TOX inhibition can potentially impede T cell exhaustion and improve ICI efficacy. Additionally, TOX expression in the TI T cells can be used for patient stratification during anti-tumor treatments, including anti-PD-1 immunotherapy.ope

점액류낭종으로 오인된 접형동에 발생한 콜레스테롤 육아종

Cholesterol granuloma is a histopathological diagnosis with features of cholesterol clefts, foreign body giant cells, and macrophages filled with hemosiderin. It is commonly found in the mastoid or petrous apex, but the involvement of paranasal sinuses is very rare. Radiologically, cholesterol granuloma show typical findings of hyperintense signals on both T1- and T2-weighted images on magnetic resonance imaging (MRI). We report two cases of cholesterol granuloma in the sphenoid sinus, which were first misinterpreted as mucoceles due to unusual MRI imagesope

Clinicopathological factors influencing the outcomes of surgical treatment in patients with T4a hypopharyngeal cancer

Background: The purpose of this study was to determine prognostic factors influencing outcomes of surgical treatment in patients with T4a hypopharyngeal cancer. Methods: The present study enrolled 93 patients diagnosed with T4a hypopharyngeal cancer who underwent primary surgery between January 2005 and December 2015 at six medical centers in Korea. Primary tumor sites included pyriform sinus in 71 patients, posterior pharyngeal wall in 14 patients, and postcricoid region in 8 patients. Seventy-two patients received postoperative radio(chemo)therapy. Results: Five-year disease-free survival (DFS) and disease-specific survival (DSS) rates were 38% and 45%, respectively. In univariate analysis, 5-year DFS was found to have significant and positive correlations with margin involvement (p < 0.001) and extracapsular spread (p = 0.025). Multivariate analysis confirmed that margin involvement (hazard ratio (HR): 2.81; 95% confidence interval (CI): 1.49-5.30; p = 0.001) and extracapsular spread (HR: 2.08; 95% CI: 1.08-3.99; p = 0.028) were significant factors associated with 5-year DFS. In univariate analysis, cervical lymph node metastasis (p = 0.048), lymphovascular invasion (p = 0.041), extracapsular spread (p = 0.015), and esophageal invasion (p = 0.033) were significant factors associated with 5-year DSS. In multivariate analysis, extracapsular spread (HR: 2.98; 95% CI: 1.39-6.42; p = 0.005) and esophageal invasion (HR: 2.87; 95% CI: 1.38-5.98; p = 0.005) remained significant factors associated with 5-year DSS. Conclusion: Margin involvement and extracapsular spread are factors influencing recurrence while extracapsular spread and esophageal invasion are factors affecting survival in patients with T4a hypopharyngeal cancer treated by primary surgery.ope

Retropharyngeal Ectopic Parathyroid Adenoma Localized by 18F-Fluorocholine Positron Emission Tomography/Computed Tomography: A Case Report

Ectopic parathyroid adenomas of the retropharyngeal space are relatively rare. Herein, we report a case of primary hyperparathyroidism (PHPT) secondary to a retropharyngeal parathyroid adenoma. A 22-year-old woman presented with elevated serum calcium and parathyroid hormone (PTH) levels, revealed during a medical check-up. The patient had a history of ureteral stones and a confirmed low bone mass. Neck 99mTechnetium-sestamibi singlephoton emission computed tomography (CT) and ultrasonography did not reveal any suspicious lesions. There was no evidence of hereditary PHPT based on the results of targeted gene sequencing. Surgical exploration was unsuccessful, and the PHPT persisted after the first surgery. Approximately a year after the failed operation, 18F-fluorocholine (FCH) positron emission tomography/CT (PET-CT) became available, and when performed, it revealed increased uptake in the retropharyngeal space of the right side of the neck. The results of parathyroid venous sampling were concordant with a >2-fold elevation of PTH level in the veins on the right side of the neck compared to the peripheral veins. The 1.8 cm-diameter mass was successfully removed resulting in an 87% reduction in intraoperative PTH level (198.0-26.5 pg/mL). Subsequently, normalizations of calcium and PTH levels were achieved. In summary, ectopic parathyroid adenomas, including retropharyngeal lesions, should also be suspected when investigating an elusive case of PHPT. 18F-FCH PET-CT can be a useful complementary modality for detecting culprit lesions.ope

Two Cases of Malleostapedotomy in Congenital Oval Window Atresia

Congenital anomaly of the oval window with an abnormal facial nerve course is an uncommon embryological defect, which is related to the underdevelopment of second branchial arch derivatives. Some treatments for improving hearing levels are available; these include hearing aids, vestibulotomy, neo-oval window formation, and stapes surgeries, including incudostapedotomy and malleostapedotomy. However, surgery for congenital anomalies of the oval window has rarely been described, usually in very small series of patients. We describe two cases of congenital anomalies of the oval window with aberrant facial nerve courses. One was a 40-year-old male diagnosed with unilateral congenital oval window atresia; the other was a 10-year-old male diagnosed with bilateral congenital oval window atresia. We also describe the clinical manifestations and treatment outcomes of malleostapedotomy for congenital anomalies of the oval window with aberrant facial nerve courses.ope

Robot-Assisted Total Thyroidectomy with or without Robot-Assisted Neck Dissection in Pediatric Patients with Differentiated Thyroid Cancer

Pediatric thyroid cancer more frequently develops cervical node metastasis than adult thyroid cancer, even in differentiated thyroid carcinoma (DTC). Thus, cervical neck dissection often needs to be performed simultaneously with thyroidectomy in pediatric patients. Herein, we describe our experience with robot-assisted total thyroidectomy with/without robot-assisted neck dissection in pediatric patients compared with the conventional operated group. A total of 30 pediatric patients who underwent thyroidectomy for DTC between July 2011 and December 2019 were retrospectively reviewed. Among them, 22 underwent robot-assisted operation, whereas 8 underwent conventional operation. There was no statistical difference in the mean operation times, blood loss, drainage amounts, and hospital stay length between the robot-assisted and conventional operation groups; however, the operation time was less in the retroauricular approach subgroup (robot-assisted operation group) with better satisfaction on cosmesis. No postoperative complications, such as seromas, hemorrhages, or hematomas were observed. Our experience suggested that robot-assisted thyroidectomy with or without neck dissection through the retroauricular approach is a feasible and safe alternative treatment, producing outstanding esthetic results compared to the conventional approach, especially in pediatric patients with DTC.ope

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.ope

Characterizing intrinsic molecular features of the immune subtypes of salivary mucoepidermoid carcinoma

Introduction: Characterizing the tumor microenvironment (TME) and immune landscape of cancer has been a promising step towards discovering new therapeutic biomarkers and guiding precision medicine; however, its application in mucoepidermoid carcinoma (MEC) has been sparse. Here, we conducted a comprehensive study to understand the properties of the TME and immune profiles of MEC. Method: 20 patients with MEC were collected from Yonsei Head and Neck Cancer Centre, Yonsei University, South Korea. Total RNA sequencing was conducted to determine gene expression profiles. Bioinformatic and immunoinformatic analyses were applied to characterize the TME and identify immunophenotypic subgroups, and to investigate the molecular features that explain the distinct phenotypes. Results: The MEC samples were subdivided into two groups, immune hot and immune cold, based on the heterogenous immune cell-infiltration and activation level. The immune-hot subgroup exhibited a higher level of immune activity, including T cell infiltration, cytolytic score, IFN-γ, antigen-presenting machinery, and immune modulator genes. Further characterizing molecular features of two subgroups, downregulation of lipid metabolic regulators, including MLXIPL and FASN, and the migration of chemokines and leukocytes were observed, respectively. And, Group-specific expression of immune checkpoint molecules, such as TIGIT, PD-L2, and CTLA-4, was observed in the immune-hot group, which can be exploited as a potential immunotherapeutic biomarker. Conclusions: Immunophenotypically heterogeneous MEC subgroups analysis has shown distinctive molecular characteristics and provided potential treatment options. These findings yield new insights into TME of MEC and may help next step to study this uncharted cancer.ope

국소 진행성 두경부암 환자에서 선행면역치료 후 수술적 치료: 수술 전후 합병증 및 치료 결과

Background and Objectives We analyzed surgical outcomes, perioperative complications, and mortality in head and neck squamous cell carcinoma (HNSCC) in patients who underwent curative surgery following neoadjuvant immunotherapy. Subjects and Method The records of 36 HNSCC patients who underwent curative surgery with neoadjuvant immunotherapy and 69 HNSCC patients who received neoadjuvant chemotherapy were analyzed. Results The average operation time was 315 minutes, and the average bleeding volume was 167 cc. The average length of hospital stay was 21 days. When evaluating surgical margin status, we found 24 patients (66.6%) who exhibited a negative margin. We found no case where surgery was impossible due to progression of the lesion during neoadjuvant immunotherapy. Compared to the neoadjuvant chemotherapy group, neoadjuvant immunotherapy group showed acceptable perioperative safety and complication profile. The postoperative complication rate was 19.4% in the neoadjuvant immunotherapy group and 13.0% in the neoadjuvant chemotherapy group (p=0.386). There were no serious complications during the recovery period after surgery or instances of death due to complications. Conclusion In HNSCC patients, there was no increase in the incidence of complications or mortality related to curative surgery after neoadjuvant immunotherapy.ope

Effect of human acellular dermal matrix (Megaderm™) on infra-auricular depressed deformities, Frey's syndrome, and first bite syndrome following parotidectomy: a multi-center prospective study

Background: Parotidectomy is the primary treatment for parotid gland tumors. However, complications may include a prominent facial scar or infra-auricular depressed deformity, Frey's syndrome, first bite syndrome, or other facial pain, numbness, and paralysis. Acellular dermal matrix (ADM) has been widely used to prevent these complications in parotid surgery, but there have been no prospective, multi-center trials documenting its efficacy. This study evaluates the effectiveness of ADM implantation in preventing infra-auricular depressed deformity, Frey's syndrome and first bite syndrome after parotidectomy. Methods: We analyzed 51 cases of standard parotidectomy and 58 cases of parotidectomy with implantation of Megaderm™ ADM through prospective multicenter trial. Acute complications including infection, seroma, hematoma, skin necrosis, and acute parotid area pain were evaluated 1 week postoperatively. Clinician grading of Frey's syndrome and blinded clinician evaluation of infra-auricular depressed deformities were conducted at 3, 6, and 12 months. Patients evaluated subjective satisfaction with neck appearance, Frey's syndrome quality, and acute parotid area pain at 3, 6, and 12 months. Results: There was a higher incidence of seroma in the Megaderm™ group than in the control group at week 1. The incidence and total clinician-evaluated Frey's syndrome scores were significantly lower in the Megaderm™ group than in the control group at 3, 6, and 12 months. Both the objective and subjective evaluations of the facial contour showed a better outcome in the Megaderm™ group compared to the control group at 3, 6, and 12 months. There were no significant differences between the groups in the patient-reported Frey's syndrome quality scores at 3, 6, and 12 months, but the Megaderm™ group reported significantly less acute pain than the control group. Conclusions: ADM implantation can effectively reduce the occurrence of Frey's syndrome, infra-auricular depressed deformity, and first bite syndrome after parotidectomy. ADM may be especially advantageous in complex parotidectomy cases when significant complications are expected.ope