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Background: To assess the efficacy of concurrent chemoradiotherapy (CCRT) with daily low-dose cisplatin (CDDP) plus weekly docetaxel (DTX) for patients with T2N0 glottic cancer.Methods: Between January 2004 and December 2013, 62 treatment-naive patients with histologically proven T2N0 glottic cancer were treated with concurrent chemoradiotherapy. Radiation therapy (RT; 2 Gy daily fractions up to a total dose of 66 Gy) was administered in combination with daily low-dose CDDP (6 mg/m2, five times a week), plus weekly DTX (10 mg/m2) for up to 4 weeks from the commencement of RT.Results: Median duration of follow-up was 70 months. The actuarial 3-year and 5-year overall survival rates were 95% and 93%. The 3-year and 5-year cause-specific survival rates were both 100%. The actuarial 3-year and 5-year local control rates were 94% and 94%, respectively. Hematologic toxicity (neutoropenia of severity ≥ Grade 3) was observed in 8% of the patients, and non-hematologic toxicity (radiation mucositis of severity ≥ Grade 3) developed in one patient (2%). Radiation dermatitis of severity ≥ Grade 3 and laryngeal necrosis developed in one patient.Conclusion: CCRT with weekly DTX and low-dose CDDP appears to be a practical and safe modality and is expected to improve local control.Trial Registration: UMIN000025046 . Registered 1 October 2015, retrospectively registered. [ABSTRACT FROM AUTHOR]

Introduction: Stereotactic body radiation therapy (SBRT) was found effective in treating laryngeal cancer with only five treatment fractions by a recent clinical trial (NCT01984502, ClinicalTrials.gov). Nevertheless, this trial used the Cyberknife system, which is not widely accessible enough to benefit all patients affected by laryngeal cancer. Our study investigates the feasibility of larynx SBRT treatment planning on a conventional gantry-based LINAC and compares its plan quality with that from the Cyberknife.Materials& Methods: Ten larynx SBRT cases were originally treated by Cyberknife using fixed cones in our institution, with plans created and optimized using the Monte-Carlo algorithm in the MultiPlan treatment planning system. These cases were retrospectively planned in the Eclipse planning system for a LINAC with the same prescription dose. We used volumetric modulated arc therapy (VMAT) for larynx SBRT planning in Eclipse and incorporated non-coplanar arcs to approach the Cyberknife's large solid angle delivery space. We used both anisotropic analytical algorithm (AAA) and Acuros XB (AXB) algorithm for dose calculation and compared their accuracy by measurements on an in-house larynx phantom. We compared the LINAC VMAT plans (VMAT-AAA and VMAT-AXB) with the original Cyberknife plans using dosimetric endpoints such as the conformity index, gradient indices (R50, R20), OAR maximum/mean doses, and the monitor units.Results: Phantom measurement showed that both the AAA and the AXB algorithms provided adequate dose calculation accuracy (94.7% gamma pass rate on 2%/2 mm criteria for AAA vs. 97.3% for AXB), though AXB provided better accuracy in the air cavity. The LINAC-based VMAT plans achieved similar dosimetric endpoints as the Cyberknife planning, and all plans met the larynx SBRT dosimetric constraints. Cyberknife plans achieved an average conformity index of 1.13, compared to 1.20 of VMAT-AXB and 1.19 of VMAT-AAA. The VMAT plans spared the thyroid gland better with average Dmean of 2.4 Gy (VMAT-AXB) and 2.7 Gy (VMAT-AAA), as compared to 4.3 Gy for Cyberknife plans. The VMAT-AAA plans had a slightly lower contralateral arytenoid Dmax (average: 15.2 Gy) than Cyberknife plans (average: 17.9 Gy) with statistical significance, while the contralateral arytenoid Dmax was similar between VMAT-AXB and Cyberknife plans with no statistically significant difference. Cyberknife plans offered slightly better R50 (average: 5.0) than VMAT-AXB (5.9) and VMAT-AAA (5.7) plans. The VMAT plans substantially reduced the plan MUs to less than 1/3 of the Cyberknife plans, and the differences were statistically significant. The other metrics were similar between VMAT and Cyberknife plans with no statistically significant differences.Conclusions: Gantry-based LINACs can achieve similar plan quality to Cyberknife systems. Treatment outcome with both methods remains to be investigated. [ABSTRACT FROM AUTHOR]