ESTRO 2024 - Abstract Book

S1382

Clinical - Head & neck

ESTRO 2024

86.0%), hypokalemia (42.9 vs 35.0%) and nausea (76.0 vs 82.6%), vomiting (38.1 vs 42.8%), hypoalbuminemia (52.4 vs 87.0%). The incidence of grade ≥3 TEAEs in the PFLL arm was 82.6, significantly lower than 47.6% in the GP arm (P=0.035), which was most common in neutropenia (9.5% in the PFLL arm vs 30.4% in the GP arm, P=0.04). Notably, we found the median initial time of grade≥3 hematological toxicity was significantly different between the PFLL arm (8.5 months) and the GP arm (1.6 months) (P=0.04). A treatment-related death occurred in the GP arm due to pneumonia.

Conclusion:

In this randomized clinical trial, PFLL combined with toripalimab may have therapeutic advantages compared with GP combined with toripalimab, which may bring better disease control and less toxicity, but more patients and longer follow-up are needed to confirm this conclusion.

Keywords: metastatic nasopharyngeal carcinoma, immunotherapy

2217

Digital Poster

Early detection of HPV-positive OPSCC: serology-based screening to foster deintensification

Thorsten Rieckmann 1,2 , Anna Sophie Hoffmann 2 , Benjamin Becker 2 , Christian Betz 2 , Kai Rothkamm 1 , Chia-Jung Busch 3,2 , Lea Schroeder 4 , Nicole Brenner 4 , Tim Waterboer 4 1 University Medical Center Hamburg-Eppendorf, Department of Radiotherapy, Hamburg, Germany. 2 University Medical Center Hamburg-Eppendorf, Department of Otorhinolaryngology, Hamburg, Germany. 3 University Medical Center Greifswald, Department of Otorhinolaryngology, Greifswald, Germany. 4 Deutsches Krebsforschungszentrum, Division of Infections and Cancer Epidemiology, Heidelberg, Germany

Purpose/Objective:

Purpose/Objective: Patients with HPV-positive orpharyngeal cancer (OPC) demonstrate a clearly favorable outcome as compared to those with HPV-negative tumors due to marked radiosensitivity. Treatment recommendations for both groups are at present identical and patients with HPV-positive OPC mostly receive intensive multimodal therapy due to the strong propensity for lymph node metastasis. Strong efforts have been and are being made to establish deintensified regimes following multiple concepts to reduce treatment-induced morbidity. Initial study results, e.g., on replacement of concomitant chemotherapy with cetuximab or on risk-adapted reduction of radiation doses after induction chemotherapy, have clearly shown that not all patients are suitable for deintensification and especially higher T and N stages remain challenging (1). HPV serology based screening could enable early detection of non-symptomatic HPV-positive OPC with low T and N stage because antibodies against the HPV16 E6 protein are detectable years before diagnosis (2). Therefore, early detection could be a means to foster the widespread and safe use of future deintensified regimes and in the best cases allow single-modality treatment, which could significantly reduce morbidity and increase patients` quality of life.