Multi-IMPT: a biologically equivalent approach to proton ARC therapy.

Objective: Proton spot-scanning arc therapy (ARC) is an emerging modality that can improve the high-dose conformity to targets compared with standard intensity-modulated proton therapy (IMPT). However, the efficient treatment delivery of ARC is challenging due to the required frequent energy changes during the continuous gantry rotation. This work proposes a novel method that delivers a multiple IMPT (multi-IMPT) plan that is equivalent to ARC in terms of biologically effective dose (BED).

Redefining Candidates for Deintensification in Locoregionally Advanced P16+ Oropharyngeal Cancer Based on Relative Risk.

Purpose: Randomized trials have found that patients with locoregionally advanced p16+ oropharyngeal squamous cell carcinoma (OPSCC) do not benefit from treatment deintensification, even among favorable risk groups. Although various methods have been used to identify candidates for treatment deintensification, the optimal approach is unknown.

Methods And Materials: We conducted a multi-institutional cohort study of 444 patients with previously untreated p16+ OPSCC undergoing definitive radiation therapy with or without systemic therapy between 2009 and 2022.

An orthogonal matching pursuit optimization method for solving minimum-monitor-unit problems: Applications to proton IMPT, ARC and FLASH.

Background: The intensities (i.e., number of protons in monitor unit [MU]) of deliverable proton spots need to be either zero or meet a minimum-MU (MMU) threshold, which is a nonconvex problem.

Adjuvant radiotherapy mitigates impact of perineural invasion on oncologic outcomes in early-stage oral cavity squamous cell carcinoma. A multi-institutional analysis of 557 patients.

Objectives: Understand the prognostic impact of perineural invasion (PNI) in early-stage oral cavity squamous cell carcinoma (OCSCC). Assess the influence of adjuvant radiotherapy on outcomes of patients with PNI-positive early-stage OCSCC.

Materials And Methods: Retrospective seven-institution cohort study including patients with pathologic T1-2 N0-1 OCSCC who underwent primary surgery with negative margins.

Prognostic Implications of Skin Invasion in Locally Advanced Oral Cavity Squamous Cell Carcinoma.

Objective: To evaluate the effect of histopathologic skin invasion on 2- and 5-year disease-free survival (DFS) and overall survival (OS) in patients treated with primary surgery for locally advanced oral cavity squamous cell carcinoma (OCSCC).

Study Design: A retrospective case-control study was performed comparing previously untreated patients with pT4a OCSCC with and without skin invasion.

Setting: Academic medical center.