Dataset Information

Accumulation of the delivered dose based on cone-beam CT and deformable image registration for non-small cell lung cancer treated with hypofractionated radiotherapy.

ABSTRACT:

Background

This study aimed to quantify the dosimetric differences between the planned and delivered dose to tumor and normal organs in locally advanced non-small cell lung cancer (LANSCLC) treated with hypofractionated radiotherapy (HRT), and to explore the necessity and identify optimal candidates for adaptive radiotherapy (ART).

Methods

Twenty-seven patients with stage III NSCLC were enrolled. Planned radiation dose was 51Gy in 17 fractions with cone-beam CT (CBCT) acquired at each fraction. Virtual CT was generated by deformable image registration (DIR) of the planning CT to CBCT for dose calculation and accumulation. Dosimetric parameters were compared between original and accumulated plans using Wilcoxon signed rank test. Correlations between dosimetric differences and clinical variables were analyzed using Mann-Whitney U test or Chi-square test.

Results

Patients had varied gross tumor volume (GTV) reduction by HRT (median reduction rate 11.1%, range?-?2.9-44.0%). The V₅₁ of planning target volume for GTV (PTV-GTV) was similar between original and accumulated plans (mean, 88.2% vs. 87.6%, p?=?0.452). Only 11.1% of patients had above 5% relative decrease in V₅₁ of PTV-GTV in accumulated plans. Compared to the original plan, limited increase (median relative increase 20 and V₃₀), esophagus (mean dose, maximum dose) and heart (mean dose, V₃₀ and V₄₀) in accumulated plans. Less than 30% of patients had above 5% relative increase of lung or heart doses. Patients with quick tumor regression or baseline obstructive pneumonitis showed more notable increase in doses to normal structures. Patients with baseline obstructive atelectasis showed notable decrease (10.3%) in dose coverage of PTV-GTV.

Conclusions

LANSCLC patients treated with HRT had sufficient tumor dose coverage and acceptable normal tissue dose deviation. ART should be applied in patients with quick tumor regression and baseline obstructive pneumonitis/atelectasis to spare more normal structures.

SUBMITTER: Wang B

PROVIDER: S-EPMC7670776 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Publications

Accumulation of the delivered dose based on cone-beam CT and deformable image registration for non-small cell lung cancer treated with hypofractionated radiotherapy.

Wang Bin B Wang Da Quan DQ Lin Mao Sheng MS Lu Shi Pei SP Zhang Jun J Chen Li L Li Qi Wen QW Cheng Zhang Kai ZK Liu Fang Jie FJ Guo Jin Yu JY Liu Hui H Qiu Bo B

BMC cancer 20201116 1

<h4>Background</h4>This study aimed to quantify the dosimetric differences between the planned and delivered dose to tumor and normal organs in locally advanced non-small cell lung cancer (LANSCLC) treated with hypofractionated radiotherapy (HRT), and to explore the necessity and identify optimal candidates for adaptive radiotherapy (ART).<h4>Methods</h4>Twenty-seven patients with stage III NSCLC were enrolled. Planned radiation dose was 51Gy in 17 fractions with cone-beam CT (CBCT) acquired at ...[more]

PMID: 33198676

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Dataset Information

Accumulation of the delivered dose based on cone-beam CT and deformable image registration for non-small cell lung cancer treated with hypofractionated radiotherapy.

Background

Methods

Results

Conclusions

Publications

Accumulation of the delivered dose based on cone-beam CT and deformable image registration for non-small cell lung cancer treated with hypofractionated radiotherapy.

Similar Datasets

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