Dose Reduction to the Swallowing Apparatus and the Salivary Glands by De-Intensification of Postoperative Radiotherapy in Patients with Head and Neck Cancer: First (Treatment Planning) Results of the Prospective Multicenter DIREKHT Trial
Abstract
:1. Background
2. Material and Methods
2.1. Target Volumes and Dose Prescriptions
2.2. Organs at Risk
2.3. Dose Limitations and Treatment Planning
2.4. Statistical Analysis
3. Results
4. Discussion
5. Conclusions
Supplementary Materials
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Characteristics | No. of Patients | % | |
---|---|---|---|
Sex | |||
Male | 19 | 63.3 | |
Female | 11 | 36.7 | |
Age at diagnosis, y | |||
Median | 59 | ||
Range | 40–80 | ||
Primary tumor site | |||
Oral cavity | 9 | 30 | |
Oropharynx | 21 | 70 | |
Base of the tongue | 4 | ||
Tonsil | 16 | ||
Other | 1 | ||
pT classification | |||
T1 | 10 | 33.3 | |
T2 | 16 | 53.3 | |
T3 | 4 | 13.3 | |
pN classification | |||
N0 | 1 | 3.3 | |
N1 | 9 | 30 | |
N2a | 10 | 33.3 | |
N2b | 10 | 33.3 | |
Perinodal spread | |||
Yes | 6 | 20 | |
No | 24 | 80 | |
Lymphangiosis | |||
L0 | 25 | 83.3 | |
L1 | 5 | 16.7 | |
Hemangiosis | |||
V0 | 28 | 93.3 | |
V1 | 2 | 6.7 | |
Perineural spread | |||
Pn0 | 24 | 80 | |
Pn1 | 6 | 20 | |
Grading | |||
G1 | 0 | 0 | |
G2 | 9 | 30 | |
G3 | 21 | 70 | |
Tracheostomy | |||
yes | 5 | 16.7 | |
yes, temporary during surgery | 15 | 50 | |
no | 10 | 33.3 | |
HPV | |||
Positive | 9 | 30 | |
Negative | 16 | 53.3 | |
Not defined | 5 | 16.7 | |
Neck dissection | |||
Only ipsilateral | 13 | 43.3 | |
Bilateral | 17 | 56.7 | |
Total removed lymph nodes, n | |||
Median | 32 | ||
Range | 12–90 | ||
No. of affected lymph nodes, n | |||
Median | 1 | ||
Range | 0–3 | ||
Simultaneous Chemotherapy, n | |||
Yes | 15 | 50 | |
No | 15 | 50 |
Organs at Risk | DIREKHT Treatment Plan Mean Dose Applied (Gy) ± Standard Deviation | Standard Treatment Plan Mean Dose Applied (Gy) ± Standard Deviation | p Value | Median Difference Between Study-and Standard Treatment Plans (Gy) (Minimum; Maximum) |
---|---|---|---|---|
Superior constrictor muscle (SCM) | 53.8 ± 6.4 | 61.3 ± 2.0 | 0.000 | 6.9 (−0.7; 20.5) |
Middle constrictor muscle (MCM) | 47.2 ± 9.3 | 59.3 ± 3.0 | 0.000 | 13.1 (−0.7; 23.3) |
Inferior constrictor muscle (ICM) | 35.9 ± 9.5 | 53.6 ± 5.0 | 0.000 | 18.2 (2.3; 32.3) |
Constrictor muscles | 48.8 ± 6.6 | 59.4 ± 2.2 | 0.000 | 10.7 (2.2; 20.9) |
Musculus cricopharyngeus | 33.6 ± 8.6 | 48.7 ± 7.6 | 0.000 | 15.5 (0.9; 29.9) |
Esophagus inlet muscle (EIM) | 37.2 ± 11.1 | 45.5 ± 10.0 | 0.000 | 6.9 (-1.4; 26.5) |
SCM to EIM | 46.3 ± 6.4 | 57.2 ± 2.9 | 0.000 | 10.5 (2.7; 20.9) |
Cervical esophagus | 29.1 ± 8.9 | 33.5 ± 6.2 | 0.002 | 3.5 (−8.3; 19.7) |
Soft palate | 59.1 ± 5.1 | 62.0 ± 2.0 | 0.002 | 1.0 (-1.9; 13.9) |
Base of tongue | 55.6 ± 7.7 | 60.7 ± 2.3 | 0.000 | 3.8 (−2.1; 19.9) |
Oral cavity | 52.2 ± 8.5 | 57.1 ± 4.5 | 0.000 | 5.7 (−2.7; 16.2) |
Glottic larynx | 30.5 ± 11.4 | 49.4 ± 8.5 | 0.000 | 17.2 (1.5; 35.6) |
Supraglottic larynx | 41.7 ± 11.2 | 57.0 ± 4.2 | 0.000 | 16.4 (−0.2; 26.4) |
Arytenoid cartilages | 30.4 ± 10.9 | 50.1 ± 7.8 | 0.000 | 19.0 (2.3; 34.8) |
Ipsilateral parotid gland | 38.9 ± 7.7 | 40.1 ± 7.5 | 0.002 | 1.5 (−3.6; 3.9) |
Contralateral parotid gland | 7.4 ± 2.2 | 21.5 ± 2.8 | 0.000 | 15.1 (6.6; 20.4) |
Total parotid gland | 23.5 ± 4.9 | 31.1 ± 4.8 | 0.000 | 8.0 (3.0; 12.2) |
Ipsilateral submandibular gland | 60.7 ± 3.7 | 62.3 ± 5.6 | 0.088 | 0.2 (−1.1; 9.2) |
Contralateral submandibular gland | 17.8 ± 13.8 | 53.7 ± 2.8 | 0.000 | 41.5 (11.4; 45.0) |
Total submandibular gland | 38.4 ± 7.8 | 57.9 ± 2.0 | 0.000 | 21.7 (5.7; 28.7) |
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Haderlein, M.; Speer, S.; Ott, O.; Lettmaier, S.; Hecht, M.; Semrau, S.; Frey, B.; Scherl, C.; Iro, H.; Kesting, M.; et al. Dose Reduction to the Swallowing Apparatus and the Salivary Glands by De-Intensification of Postoperative Radiotherapy in Patients with Head and Neck Cancer: First (Treatment Planning) Results of the Prospective Multicenter DIREKHT Trial. Cancers 2020, 12, 538. https://doi.org/10.3390/cancers12030538
Haderlein M, Speer S, Ott O, Lettmaier S, Hecht M, Semrau S, Frey B, Scherl C, Iro H, Kesting M, et al. Dose Reduction to the Swallowing Apparatus and the Salivary Glands by De-Intensification of Postoperative Radiotherapy in Patients with Head and Neck Cancer: First (Treatment Planning) Results of the Prospective Multicenter DIREKHT Trial. Cancers. 2020; 12(3):538. https://doi.org/10.3390/cancers12030538
Chicago/Turabian StyleHaderlein, Marlen, Stefan Speer, Oliver Ott, Sebastian Lettmaier, Markus Hecht, Sabine Semrau, Benjamin Frey, Claudia Scherl, Heinrich Iro, Marco Kesting, and et al. 2020. "Dose Reduction to the Swallowing Apparatus and the Salivary Glands by De-Intensification of Postoperative Radiotherapy in Patients with Head and Neck Cancer: First (Treatment Planning) Results of the Prospective Multicenter DIREKHT Trial" Cancers 12, no. 3: 538. https://doi.org/10.3390/cancers12030538