Giant Pilomatricoma Mistaken for a Malignant Tumor.

Pilomatricomas are tumors originating from the matrices of hair follicles. Giant pilomatricomas, defined as pilomatricomas that are 5 cm or larger, are benign but may appear malignant clinically. We present the case of a 69-year-old man with a rapidly growing mass on his scalp. When he visited our department, the tumor measured 10.0×6.0×4.0 cm and showed inflammation and ulceration. Magnetic resonance imaging and 18 F-fluorodeoxyglucose positron emission tomography-computed tomography showed findings resembling lymph node metastasis from a malignant tumor. However, upon an incisional biopsy, the tumor was diagnosed as a pilomatricoma. Therefore, we performed an excisional biopsy instead of radical surgery and lymph node dissection. The tumor was ultimately diagnosed as a giant pilomatricoma based on the excisional biopsy, and the patient received reconstruction only at the site of the defect. A giant pilomatricoma can be mistaken for a malignant tumor due to its characteristics. In such uncertain cases, it can be helpful to first perform an excisional biopsy.

A Case Report for Acute Myopericarditis After NVX-CoV2373 (Novavax®) COVID-19 Vaccination.

Post-vaccination myocarditis after administration of the NVX-CoV2373 coronavirus disease 2019 (COVID-19) vaccine has been reported in a limited population. We report the first biopsy-proven case of myopericarditis after administration of second dose of NVX-CoV2373 COVID-19 vaccine (Novavax®) in Korea. A 30-year-old man was referred to emergency department with complaints of chest pain and mild febrile sense for two days. He received the second dose vaccine 17 days ago. Acute myopericarditis by the vaccination was diagnosed by cardiac endomyocardial biopsy. He was treated with corticosteroid 1 mg/kg/day for 5 days and tapered for one week. He successfully recovered and was discharged on the 12th day of hospitalization. The present case suggests acute myopericarditis as a vaccination complication by Novavax® in Korea.

STAT3 phosphorylation inhibition for treating inflammation and new bone formation in ankylosing spondylitis.

OBJECTIVE: AS is a rheumatic disease characterized by chronic inflammation and bony ankylosis. This study was to evaluate whether a signal transducer and activator of transcription 3 phosphorylation inhibitor (stat3-p Inh) could treat both chronic inflammation and bone formation in AS. METHODS: Primary AS osteoprogenitor cells and spinal entheseal cells were examined for osteogenic differentiation. SF mononuclear cells (SFMCs) and lamina propria mononuclear cells (LPMCs) were obtained from AS patients. Inflammatory cytokine-producing cells were analysed using flow cytometry and ELISA. Female SKG mice were treated with stat3-p Inh, IL-17A blocker or vehicle. Inflammation and new bone formation were evaluated using immunohistochemistry, PET and micro-CT. RESULTS: In the SKG mouse model, stat3-p Inh significantly suppressed arthritis, enthesitis, spondylitis and ileitis. In experiments culturing SFMCs and LPMCs, the frequencies of IFN-γ-, IL-17A- and TNF-α-producing cells were significantly decreased after stat3-p Inh treatment. When comparing current treatments for AS, stat3-p Inh showed a comparable suppression effect on osteogenesis to Janus kinase inhibitor or IL-17A blocker in AS-osteoprogenitor cells. Stat3-p Inh suppressed differentiation and mineralization of AS-osteoprogenitor cells and entheseal cells toward osteoblasts. Micro-CT analysis of hind paws revealed less new bone formation in stat3-p Inh-treated mice than vehicle-treated mice (P = 0.005). Hind paw and spinal new bone formation were similar between stat3-p Inh- and anti-IL-17A-treated SKG mice (P = 0.874 and P = 0.117, respectively). CONCLUSION: Stat-3p inhibition is a promising treatment for both inflammation and new bone formation in AS.

Uric acid as a risk factor for progression to chronic kidney disease in patients with lupus nephritis: results from the KORNET registry.

OBJECTIVES: Little is known regarding the effect of hyperuricaemia on the progression of kidney function in patients with lupus nephritis (LN). Thus, we investigated the effect of uric acid (UA) on the long-term outcome of patients with biopsy-proven LN. METHODS: Data were obtained from KORNET, a prospective longitudinal systemic lupus erythematosus registry in the Republic of Korea. All 137 patients with LN included in this study had undergone a kidney biopsy and were subsequently treated with immunosuppressants. The patients were divided into two groups: UA ≤7 mg/dL and >7 mg/dL; their sociodemographic, clinical, treatment-related data, and outcomes were compared. Cox-proportional regression analyses were performed to identify independent predictors of renal outcome in patients with LN. RESULTS: Among the 137 patients, 37 (27.0%) had UA >7 mg/dL. This higher UA group included fewer women, but more patients with hypertension, proliferative type LN, and a chronicity index >12. The 24-h urinary protein excretion and the creatinine level were higher in this group; haemoglobin, platelet, and albumin levels were lower. During 85.0 months of follow-up, complete remission at 1 year was less frequent in the higher UA group, whereas chronic kidney disease (CKD) and end-stage renal disease were more prevalent. In the Cox proportional hazards regression analysis, UA >7 mg/dL was a signi cant predictor of progression to CKD in patients with LN (hazard ratio=2.437; p=0.020). CONCLUSIONS: Our findings suggest that hyperuricaemia at LN onset is an independent risk factor that predicts the development of CKD in patients with LN.

Delayed diagnosis of lung cancer due to misdiagnosis as worsening of sarcoidosis: a case report.

BACKGROUND: The concurrence of sarcoidosis and primary lung cancer is very rare. We report a very rare case with a delayed diagnosis of primary lung cancer due to its misdiagnosis as worsening of pulmonary sarcoidosis. CASE PRESENTATION: A 68-year-old man presented to the outpatient department for evaluation of a mass in the right hilar area with lymphadenopathies in subcarinal and both interlobar areas on chest computed tomography (CT). Sufficient core samples were obtained from subcarinal and bilateral interlobar lymph nodes using endobronchial ultrasonography (EBUS) guided transbronchial needle aspiration (TBNA). EBUS could not reach the right hilar lymph node due to its high angle. The pathologic findings were consistent with sarcoidosis. After 5 months, chest CT revealed aggravation of the right upper paratracheal lymphadenopathy. Assuming worsening of sarcoidosis, he was prescribed an oral corticosteroid for 5 months. However, follow-up chest CT showed a newly developed right lower paratracheal lymphadenopathy and worsening right hilar lymphadenopathy. Bronchoscopy and EBUS were performed once again. Transbronchial lung biopsy from the right upper lobe and EBUS-TBNA from the right lower paratracheal lymph node revealed adenocarcinoma from the lung. CONCLUSIONS: Although coexistence of sarcoidosis and lung cancer is very rare, the clinician should consider the possibility of accompanying lung cancer in sarcoidosis patients who are not responding to initial corticosteroid therapy.

APE1 Promotes Pancreatic Cancer Proliferation through GFRα1/Src/ERK Axis-Cascade Signaling in Response to GDNF.

Pancreatic cancer is the worst exocrine gastrointestinal cancer leading to the highest mortality. Recent studies reported that aberrant expression of apurinic/apyrimidinic endodeoxyribonuclease 1 (APE1) is involved in uncontrolled cell growth. However, the molecular mechanism of APE1 biological role remains unrevealed in pancreatic cancer progression. Here, we demonstrate that APE1 accelerates pancreatic cancer cell proliferation through glial cell line-derived neurotrophic factor (GDNF)/glial factor receptor α1 (GFRα1)/Src/ERK axis-cascade signaling. The proliferation of endogenous APE1 expressed-MIA PaCa-2, a human pancreatic carcinoma cell line, was increased by treatment with GDNF, a ligand of GFRα1. Either of downregulated APE1 or GFRα1 expression using small interference RNA (siRNA) inhibited GDNF-induced cancer cell proliferation. The MEK-1 inhibitor PD98059 decreased GDNF-induced MIA PaCa-2 cell proliferation. Src inactivation by either its siRNA or Src inhibitor decreased ERK-phosphorylation in response to GDNF in MIA PaCa-2 cells. Overexpression of GFRα1 in APE1-deficient MIA PaCa-2 cells activated the phosphorylation of Src and ERK. The expression of both APE1 and GFRα1 was gradually increased as progressing pancreatic cancer grades. Our results highlight a critical role for APE1 in GDNF-induced pancreatic cancer cell proliferation through APE1/GFRα1/Src/ERK axis-cascade signaling and provide evidence for future potential therapeutic drug targets for the treatment of pancreatic cancer.

A Prospective Observational Study Evaluating the Correlation of c-MET Expression and EGFR Gene Mutation with Response to Erlotinib as Second-Line Treatment for Patients with Advanced/Metastatic Non-Small-Cell Lung Cancer.

OBJECTIVES: We aimed to evaluate the prevalence and predictive role of c-MET expression and EGFR mutation in the efficacy of erlotinib in non-small-cell lung cancer (NSCLC). METHODS: We prospectively recruited 196 patients with stage IV or recurrent NSCLC treated with erlotinib after failure of first-line chemotherapy. Immunohistochemistry was used to evaluate c-MET overexpression, silver in situ hybridization (SISH) to assess gene copy number, and real-time polymerase chain reaction to detect EGFR mutations, respectively, in tumor tissue. RESULTS: The major histologic type was adenocarcinoma (66.8%). c-MET was overexpressed in 55.8% (87/156) and dominant in females as well as non-squamous histology. Although c-MET gene amplification and high polysomy were observed in 2.0% (3/152) and 11.2% (17/152), they did not correlate with any characteristics. EGFR mutation was detected in 13.1% (20/153). The objective response rate of erlotinib was higher (61.1 vs. 3.7%, p < 0.001) and the median progression-free survival (PFS) was longer (10.2 vs. 1.9 months, p < 0.001) in EGFR-sensitizing mutations. However, c-MET positivity did not show a significant correlation with response to erlotinib or PFS. CONCLUSION: We reconfirmed EGFR mutation as a strong predictive marker of NSCLC. However, c-MET positivity was not associated with response or PFS, although c-MET overexpression correlated with some clinical characteristics.

Efficacy of Afatinib in a Previously-Treated Patient with Non-Small Cell Lung Cancer Harboring HER2 Mutation: Case Report.

Human epidermal growth factor receptor 2 (HER2) mutation in non-small cell lung cancer (NSCLC) is an oncogenic driver that possibly becomes a druggable target to HER2-targeted therapy. The benefit of HER2-targeted therapy is much less defined especially in eastern populations. We provide evidence of clinical benefit of afatinib in a 50-year-old Asian woman with HER2-mutant NSCLC who previously failed cytotoxic chemotherapy and gefitinib treatment. Next-generation sequencing of the tumor tissue revealed a HER2 exon 20 mutation (c.2437A>G), which has never been reported. The patient was treated with afatinib for more than four months. She showed rapid radiologic response within a month, and maintained stable state until the last dose of afatinib.

Anatomic mapping and clinicopathologic analysis of benign acral melanocytic neoplasms: A comparison between adults and children.

BACKGROUND: The clinicopathologic features of benign acral melanocytic neoplasms (BAMNs) remain poorly understood. OBJECTIVE: To define the clinicopathologic features of BAMNs. METHODS: We analyzed clinical data and mapped BAMNs anatomically. We also reviewed the histopathologic features of BAMNs and compared these between adults and children. RESULTS: We included 396 cases of BAMN: 335 adults and 61 children (376 acquired and 20 congenital lesions). Anatomic mapping revealed that the nonweight-bearing portion of the foot was the most common site in adults (120/335, 35.8%) and the forefoot the most common site in children (17/61, 27.9%) for BAMNs. The long axes of the BAMNs paralleled the dermatoglyphic lines on the palms and soles, as did most tissue sections. The lesion diameters were <5.7 mm in all acquired lesions. Histopathologically, we diagnosed 69 lentigo simplex, 201 junctional, 114 compound, 8 intradermal, and 4 blue nevi. Corneal pigmentation, nests located between rete ridges, dendrite prominence, and cytologic atypia were all significantly more common in children than adults. LIMITATIONS: The retrospective study design and acquiring patients from a single institution of a single country limited the research results. CONCLUSION: BAMNs develop most commonly on nonweight-bearing regions of the soles in adults and on the forefoot in children. The long axis of the lesion follows the dermatoglyphics, and cytologic atypia is more common in children.

Other primary systemic cancers in patients with melanoma: Analysis of balanced acral and nonacral melanomas.

BACKGROUND: Although other primary systemic cancers in patients with melanoma have been studied, there have been few focusing on acral melanomas. OBJECTIVES: We assessed other primary systemic cancers in patients with acral and nonacral melanomas. METHODS: We analyzed other primary cancers in 452 patients with melanoma from 1994 to 2013. Metachronous cancers were defined as those given a diagnosis more than 2 months after diagnosis of melanoma. The others were considered prechronous or synchronous cancers. RESULTS: Among 51 cases of other primary cancers, gastrointestinal cancer (35.3%, n = 18/51) was the most common, followed by thyroid (17.6%), lung (11.8%), and breast (5.9%). Those were more prevalent in the acral melanoma group (12.8%, n = 31/243) compared with the nonacral melanoma group (9.6%, n = 20/209). Of 23 cases of metachronous cancer, the risk was the highest in bone marrow, followed by oral cavity, bladder, colon, lung, and thyroid. Among 28 cases of prechronous or synchronous cancers, gastrointestinal tract (35.7%, n = 10/28) was the most common site, followed by thyroid (17.9%), breast (10.7%), and lung (7.1%). LIMITATIONS: The study is limited by a small number of patients. CONCLUSION: Careful follow-up and imaging studies are necessary for early detection of other primary cancers and metastatic lesions in patients with melanoma.

Carcinoid tumor associated with adjacent dysplastic columnar epithelium in the renal pelvis: A case report and literature review.

Carcinoid tumors are well documented in the pulmonary and gastrointestinal systems, but very rare in the urinary tract, especially in the renal pelvis. We report on a 60-year-old female patient who presented with left flank pain and fever. Abdominal computed tomography demonstrated a heterogeneously enhancing mass in the left renal pelvis and a stone at the left proximal ureter. Multiple parenchymal lesions were also observed, which were identified as uneven caliectasis displaying air-fluid levels and renal parenchymal atrophy. The patient underwent simple nephro-ureterectomy. Macroscopically, a polypoid mass was observed in the renal pelvis. Microscopically, the tumor revealed acinar, tubular, and solid pattern and was composed of small, monotonous and hyperchromatic cells. Lining epithelia in renal pelvis and ureter revealed columnar epithelia with dysplastic change. The tumor cells were positive for chromogranin A, synaptophysin, CD56, and focally positive for cytokeratin. Immunohistochemical staining of synaptophysin and chromogranin A highlighted the neuroendocrine cells in the columnar epithelium. Ki-67 (1:50; MIB-1) labeling index was less than 1% in the area with highest uptake. We report here a case of carcinoid tumor of the renal pelvis that was associated with adjacent dysplastic columnar epithelium.

Depletion of the cereblon gene activates the unfolded protein response and protects cells from ER stress-induced cell death.

Previous studies showed that cereblon (CRBN) binds to various cellular target proteins, implying that CRBN regulates a wide range of cell responses. In this study, we found that deletion of the Crbn gene desensitized mouse embryonic fibroblast cells to various cell death-promoting stimuli, including endoplasmic reticulum stress inducers. Mechanistically, deletion of Crbn activates pathways involved in the unfolded protein response prior to ER stress induction. Loss of Crbn activated PKR-like ER kinase (PERK) with enhanced phosphorylation of eIF2α. Following ER stress induction, loss of Crbn delayed dephosphorylation of eIF2α, while reconstitution of Crbn reversed enhanced phosphorylation of PERK and eIF2α. Lastly, we found that activation of the PERK/eIF2α pathway following Crbn deletion is caused by activation of AMP-activated protein kinase (AMPK). We propose that CRBN plays a role in cellular stress signaling, including the unfolded protein response, by controlling the activity of AMPK.

TCL1 expression predicts overall survival in patients with mantle cell lymphoma.

OBJECTIVES: Mantle cell lymphoma (MCL) has a heterogeneous clinical course. Although most cases show a poor prognosis, a minority has an indolent course. It is difficult to identify indolent MCL cases prospectively. T-cell leukemia/lymphoma protein 1 (TCL1) is expressed by several B-cell lymphomas, including MCL. This study examined the expression of TCL1 and its prognostic relevance for MCL. METHODS: Clinical data for 162 patients with MCL were collected. Of these, 144 cases with available tissues for tissue microarray construction and immunostaining were included in the analysis. TCL1 staining was quantified using the Nuclear Quant application with Pannoramic™ Viewer v. 1.14. High TCL1 expression was defined as moderate to strong nuclear and/or cytoplasmic staining in 40% or more of the cells. RESULTS: High TCL1 expression was observed in 39 of 144 samples (27.1%). Patients with low TCL1 expression were more likely to present with blastoid/pleomorphic morphology (P = 0.010). Low TCL1 expression was associated with significantly shorter overall survival (OS, P = 0.006). Multivariate analysis identified low TCL1 expression (P = 0.003), high-risk MIPI (P = 0.027), and anemia (P = 0.018) as adverse prognostic factors. CONCLUSIONS: Our study suggests that TCL1 expression profile may have a role in the prediction of overall outcome in patient with MCL and call for prospective studies.

Pulmonary epithelioid hemangioendothelioma misdiagnosed as a benign nodule.

Pulmonary epithelioid hemangioendothelioma (PEH) is a rare vascular tumor of borderline malignancy that originates from endothelial cells. Chest computed tomography (CT) performed during a routine cancer screening revealed multiple small pulmonary nodules in a 50-year-old man who had previously undergone endoscopic submucosal dissection of early gastric cancer. To rule out metastatic nodules, a wedge resection of the left upper lobe was performed and the frozen biopsy reported a benign fibrotic nodule. Using immunohistochemistry, the final pathology was indicated to be PEH, and consecutive surgery for the right-side nodules was planned and performed.

Frequent detection of BRAF(V600E) mutations in histiocytic and dendritic cell neoplasms.

AIMS: In this study, we examined BRAF mutation in a wide range of histiocytic and dendritic cell neoplasms and compared its detection rate in each disease group. METHODS AND RESULTS: A total of 129 cases of histiocytic, dendritic cell and other related lesions were reviewed from the archives of 10 hospitals in Korea. The cases consisted of histiocytic sarcoma, follicular dendritic cell (FDC) sarcoma, interdigitating cell sarcoma, Langerhans cell histiocytosis (LCH), Langerhans cell sarcoma, blastic plasmacytoid dendritic cell neoplasm, acute monocytic leukaemia M5, giant cell tumour, xanthogranuloma, inflammatory myofibroblastic tumour and Rosai-Dorfman disease. BRAF mutation analysis was performed by Sanger sequencing and PNAcqPCR. All the detected mutations of BRAF were V600E. Histiocytic sarcoma exhibited the highest rate of BRAF(V600E) (62.5%, five of eight), followed by Langerhans cell tumours (25%, seven of 28), FDC sarcoma (18.5%, five of 27) and giant cell tumour (6.7%, two of 30). The other tumours did not harbour BRAF mutations. In histiocytic sarcoma, FDC sarcoma and LCH, there were no significant differences in clinical features between tumours containing BRAF(V600E) and those with BRAF(wt) . CONCLUSIONS: BRAF(V600E) was not limited to LCH and was detected more frequently in histiocytic sarcoma. Our findings suggest that the BRAF pathway may contribute to the pathogenesis or malignant transformation of histiocytic and dendritic cell neoplasms.

Common genetic variants at 1q22 and 10q23 and gastric cancer susceptibility in a Korean population.

Genetic variants at 1q22 and 10q23 were identified as genetic markers of both gastric cancer and esophageal squamous cell carcinoma susceptibility by two genome-wide association studies. The aim of this study was to determine whether rs4072037A > G in MUC1 at 1q22 and rs2274223A > G in PLCE1 at 10q23 are associated with a risk of gastric cancer in a Korean population. We conducted a large-scale case-control study of 3,245 patients with gastric cancer and 1,700 controls. The allele frequencies of rs4072037G and rs2274223G were 11.2 and 25.5% among patients with gastric cancer, compared with 12.8 and 26.4%, respectively, among controls. We found that the rs4072037 AG genotype was significantly associated with a reduced risk of gastric cancer [odds ratios (OR) = 0.78; 95% confidence interval (CI) = 0.67-0.91 for AG vs AA]. Compared with the rs2274223 AA genotype, we found a significant association between the rs2274223 AG genotype and a weakly reduced risk of gastric cancer (OR = 0.87; 95% CI = 0.76-0.99 for AG vs AA). Our data suggest that genetic variants at 1q22 and 10q23 play a role in gastric carcinogenesis.

Expression of matrix metalloproteinases and their inhibitors in different immunohistochemical-based molecular subtypes of breast cancer.

BACKGROUND: Metalloproteinases (MMPs) and their tissue inhibitors of metalloproteinases (TIMPs) are involved in several key pathways of tumor growth, invasion and metastasis, but little is known about their expression according to different molecular subtypes of breast cancer. The aims of this study were to assess the prevalence and clinical significance of MMP and TIMP expression in invasive breast cancer and to determine its association with immunohistochemical-based molecular classification. METHODS: Tissue microarray sections were immunostained for estrogen receptor-α (ER-α), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), cytokeratin (CK) 5/6, epidermal growth factor receptor (EGFR) and with specific antibodies against MMP-1, 2, 7, 9, 11, 13, and 14 and TIMP-1, 2, and 3. Based on the immunostaining data from five of the markers used (ER-α, PR, HER2, EGFR and CK5/6), three major subtypes (123 luminal A, 31 basal-like, and 17 HER2-overexpressing) were selected. RESULTS: Statistically significant differences in the expression of MMPs and TIMPs among the three subtypes were found in tumoral MMP7 (P = 0.005), tumoral MMP-9 (P = 0.000), tumoral MMP-13 (P = 0.016) and stromal MMP-13 (P = 0.016). The incidence of tumoral MMP-9 expression in the HER2-overexpressing subtype was significantly higher than in the luminal A subtype (P = 0.021). Tumoral MMP-9 and stromal MMP-13 expression were significantly higher in the HER2-overexpressing subtype than in the basal-like subtype (P = 0.000 and P = 0.016, respectively). Tumoral MMP-7 expression was significantly higher in the basal-like subtype compared to luminal A (P = 0.007) and HER2-overexpressing subtype (P = 0.004). Tumoral MMP-13 showed a higher expression in the basal-like subtype than in the HER2-overexpressing subtype (P = 0.010). In multivariate analysis, stage and stromal MMP-1 expression were significantly related to overall survival. Stage was of independent prognostic significance for disease-free survival. CONCLUSION: We found some variations in MMP and TIMP expression among the immunohistochemical-based molecular subtypes of breast carcinomas, suggesting differences in their tumor pathophysiology. Additional studies are needed to determine the mechanisms underlying the differences of MMP and TIMP expression in the molecular subtypes for the development of specific therapeutic targets for breast cancer subtypes.

Different protein expression associated with chemotherapy response in oropharyngeal cancer according to HPV status.

BACKGOUND: Oropharyngeal cancer (OPC) associated with human papilloma virus (HPV OPC) shows better treatment outcomes than non-HPV OPC. We investigated the expression of p53, ß-tubulin, bcl-2 and ERCC 1, which are well-known biomarkers to predict the chemotherapy response, according to HPV status in OPC patients. METHODS: Patients who treated with at least 2 cycles of induction chemotherapy followed by concurrent chemoradiotherapy for locally advanced oropharyngeal cancer were reviewed. HPV PCR and immunohistochemical stain was done in paraffin embedded tumor tissue and evaluated the relation with the chemotherapy response and survival outcomes according to HPV status. RESULTS: Seventy-four patients were enrolled for this study and all patients received induction chemotherapy with docetaxel, 5-FU and cisplatin. After induction chemotherapy, complete response (CR) was shown in 22 patients (30%) and partial response (PR) in 46 patients (62%). HPV + was detected in 21 patients (28%), while 35 patients (47%) showed p16+ expression by IHC analysis. p16 positive patients showed better overall response, PFS and OS than p16 negative patients. p53 and class III beta-tubulin expression were significantly higher in HPV- and p16- than HPV + and p16+ patients. Conversely, bcl-2 expression was greater in HPV + or p16+ than HPV- or p16- patients. ERCC1 expression did not differ significantly according to HPV status. In multivariate analyses, early T stage (p = 0.036) and good PS (PS 0) (p = 0.029) showed a better 3Y-PFS rate, and low p53 expression (p = 0.012) and complete response after induction chemotherapy (p = 0.026) were highly associated with 3Y-OS rate. Low expression of p53 and p16 positive patients showed significantly prolonged OS than others (p = 0.010). CONCLUSION: P53, class III beta-tubulin and bcl-2 were differently expressed in OPC according to HPV status and present study suggested the underlying mechanism of better response to chemotherapy in case of HPV OPC than non-HPV OPC. Among these biomarkers, p53 is the strongest prognostic marker in OPC and p53 in addition to p16 support the rationale to study of de-escalation strategy for OPC.