G Protein-Coupled Receptor Genes, PTGDR1, PTGDR2, and PTGIR, Are Candidate Epigenetic Biomarkers and Predictors for Treated Patients with HPV-Associated Oropharyngeal Cancer
Authors: Misawa, Kiyoshi; Imai, Atsushi; Kanazawa, Takeharu; Mima, Masato; Yamada, Satoshi; Mochizuki, Daiki; Yamada, Taiki; Shinmura, Daichi; Ishikawa, Ryuji; Kita, Jyunya; Yamaguchi, Yuki; Misawa, Yuki; Mineta, Hiroyuki
Differences in the biology of human papillomavirus (HPV)-associated oropharyngeal cancers (OPCs) and HPV-negative OPCs may have implications in patient management. Early detection is imperative to reduce HPV-associated OPC mortality. Circulating tumor DNA (ctDNA) can potentially serve as a biomarker for monitoring clinically relevant cancer-related genetic and epigenetic modifications. We analyzed the methylation status of 24 G protein-coupled receptor (GPCR) genes in verification (85 OPC primary samples) and validation (8 OPC ctDNA samples) studies using quantitative methylation-specific polymerase chain reaction (Q-MSP). The Q-MSP-based verification study with 85 OPC primary samples revealed the GPCR genes that were significantly associated with recurrence in high methylation groups (>= 14 methylated genes) with OPC and HPV-associated OPC (p < 0.001). In the Kaplan-Meier estimate and multivariate Cox proportional hazard analyses, 13 GPCR genes were significantly related to increased recurrence in the methylation group. Furthermore, the validation study on ctDNA showed that three of these genes (Prostaglandin D2 receptor 1: PTGDR1, Prostaglandin D2 receptor 2: PTGDR2, and Prostaglandin I2 Receptor: PTGIR) had a prediction performance as emerging biomarkers. We characterized the relationship between the methylation status of GPCR genes and outcomes in HPV-associated OPC. Our results highlight the potential utility of ctDNA methylation-based detection for the clinical management of HPV-associated OPC.
Radiotherapy in Metastatic Oropharyngeal Cancer
Authors: Nguy, Susanna; Oh, Cheongeun; Karp, Jerome M.; Wu, Shengyang Peter; Li, Zujun; Persky, Michael J.; Hu, Kenneth S.; Givi, Babak; Tam, Moses M.
Objectives The role of locoregional radiotherapy for metastatic oropharyngeal squamous cell cancer (OPSCC) is unclear. We investigated the impact of head and neck radiotherapy on survival in de novo metastatic OPSCC patients who received systemic therapy. Methods We queried the NCDB from 2004-2015 for metastatic OPSCC patients at diagnosis with known HPV-status who received systemic therapy. The association of head and neck radiotherapy with overall survival was analyzed using the Kaplan-Meier method, Cox proportional hazards model, and propensity score-matched analysis adjusting for demographic and disease-specific prognostic factors. Results Of the 2,139 patients with metastatic OPSCC who presented with metastases and received systemic treatment, we identified 556 patients with known HPV-status. Among these 556 patients, 49% were HPV-positive and 56% received head and neck radiotherapy. With a median follow-up of 17.5 months (IQR 6.0-163.4 months), radiotherapy was associated with significantly improved 1-year OS (67% vs 58%, log-rank P < .001) which remained significant on MVA (HR 0.78 95% CI 0.62-0.97 P = .029). In HPV-status subgroup analysis, a survival benefit was identified in HPV-positive patients (1-year OS 77% vs 67%, log-rank P < .001) but not in HPV-negative patients. Results were consistent on a propensity score-matched analysis of 212 HPV-positive matched patients (HR 0.66, 95% CI 0.49-0.83, P < .001). Conclusion The survival of metastatic OPSCC remains limited. In this large series of patients with known HPV-status, head and neck radiotherapy was associated with longer survival in those with HPV-associated disease. These data could guide management of this challenging group of patients for head and neck cancer practitioners. Level of Evidence 3 Laryngoscope, 2020