Dataset Information

The Importance of Verification CT-QA Scans in Patients Treated with IMPT for Head and Neck Cancers.

ABSTRACT:

Purpose

To understand how verification computed tomography-quality assurance (CT-QA) scans influenced clinical decision-making to replan patients with head and neck cancer and identify predictors for replanning to guide intensity-modulated proton therapy (IMPT) clinical practice.

Patients and methods

We performed a quality-improvement study by prospectively collecting data on 160 consecutive patients with head and neck cancer treated using spot-scanning IMPT who underwent weekly verification CT-QA scans. Kaplan-Meier estimates were used to determine the cumulative probability of a replan by week. Predictors for replanning were determined with univariate (UVA) and multivariate (MVA) Cox model hazard ratios (HRs). Logistic regression was used to determine odds ratios (ORs). P < .05 was considered statistically significant.

Results

Of the 160 patients, 79 (49.4%) had verification CT-QA scans, which prompted a replan. The cumulative probability of a replan by week 1 was 13.7% (95% confidence interval [CI], 8.82-18.9), week 2, 25.0% (95% CI, 18.0-31.4), week 3, 33.1% (95% CI, 25.4-40.0), week 4, 45.6% (95% CI, 37.3-52.8), and week 5 and 6, 49.4% (95% CI, 41.0-56.6). Predictors for replanning were sinonasal disease site (UVA: HR, 1.82, P = .04; MVA: HR, 3.64, P = .03), advanced stage disease (UVA: HR, 4.68, P < .01; MVA: HR, 3.10, P < .05), dose > 60 Gy equivalent (GyE; relative biologic effectiveness, 1.1) (UVA: HR, 1.99, P < .01; MVA: HR, 2.20, P < .01), primary disease (UVA: HR, 2.00 versus recurrent, P = .01; MVA: HR, 2.46, P = .01), concurrent chemotherapy (UVA: HR, 2.05, P < .01; MVA: not statistically significant [NS]), definitive intent treatment (UVA: HR, 1.70 versus adjuvant, P < .02; MVA: NS), bilateral neck treatment (UVA: HR, 2.07, P = .03; MVA: NS), and greater number of beams (5 beam UVA: HR, 5.55 versus 1 or 2 beams, P < .02; MVA: NS). Maximal weight change from baseline was associated with higher odds of a replan (≥3 kg: OR, 1.97, P = .04; ≥ 5 kg: OR, 2.13, P = .02).

Conclusions

Weekly verification CT-QA scans frequently influenced clinical decision-making to replan. Additional studies that evaluate the practice of monitoring IMPT-treated patients with weekly CT-QA scans and whether that improves clinical outcomes are warranted.

SUBMITTER: Evans JD

PROVIDER: S-EPMC7574830 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Publications

The Importance of Verification CT-QA Scans in Patients Treated with IMPT for Head and Neck Cancers.

Evans Jaden D JD Harper Riley H RH Petersen Molly M Harmsen William S WS Anand Aman A Hunzeker Ashley A Deiter Noelle C NC Schultz Heather H Jethwa Krishan R KR Lester Scott C SC Routman David M DM Ma Daniel J DJ Garces Yolanda I YI Neben-Wittich Michelle A MA Laack Nadia N NN Beltran Chris J CJ Patel Samir H SH McGee Lisa A LA Rwigema Jean-Claude M JM Mundy Daniel W DW Foote Robert L RL

International journal of particle therapy 20200803 1

<h4>Purpose</h4>To understand how verification computed tomography-quality assurance (CT-QA) scans influenced clinical decision-making to replan patients with head and neck cancer and identify predictors for replanning to guide intensity-modulated proton therapy (IMPT) clinical practice.<h4>Patients and methods</h4>We performed a quality-improvement study by prospectively collecting data on 160 consecutive patients with head and neck cancer treated using spot-scanning IMPT who underwent weekly v ...[more]

PMID: 33094135

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Dataset Information

The Importance of Verification CT-QA Scans in Patients Treated with IMPT for Head and Neck Cancers.

Purpose

Patients and methods

Results

Conclusions

Publications

The Importance of Verification CT-QA Scans in Patients Treated with IMPT for Head and Neck Cancers.

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