Table 4.
Median doses (median of the median dose) to the swallowing structures in all patients and comparison to reported series
| Swallowing structures | Current study | Feng et al 2007 [21] | Levendag et al* 2007 [7] | ||||
|---|---|---|---|---|---|---|---|
| Median | Range | Median | Range | Median | Range | ||
| PCs | Volume (cc) | 20 | 11-32 | NA | NA | NA | NA |
| Dose (Gy) | 59 | 39-66 | 64 | 51-72 | 48 | 6.0-73.0 | |
| scm | Volume (cc) | 12 | 6-21 | NA | NA | NA | NA |
| Dose (Gy) | 59.4 | 24-69 | 68 | 57-74 | 51 | 22.0-73.0 | |
| mcm | Volume (cc) | 3.6 | 1.5-9 | NA | NA | NA | NA |
| Dose (Gy) | 59 | 37.0-71.5 | 64 | 53-75 | 48 | 11.0-72.0 | |
| icm | Volume (cc) | 3.7 | 0.9-7 | NA | NA | NA | NA |
| Dose (Gy) | 53 | 29-73 | 51 | 30-70 | 32 | 6.0-73.0 | |
| GSL | Volume (cc) | 15.3 | 6.4-23 | NA | NA | NA | NA |
| Dose (Gy) | 53 | 28-70 | 55 | 22-72 | NA | NA | |
| eim | Volume (cc) | 5.4 | 0.7-44 | NA | NA | NA | NA |
| Dose (Gy) | 39 | 16.0-67.8 | 44 | 15-66 | 18 | 3.0-64.0 | |
*The results are not entirely comparable with the study of Levendag et al [7], as there is a difference in the delineation of muscular structures. In Levendag et al. the anterior part of scm and mcm were not delineated and eim was defined as the proximal 1 cm of the esophageal inlet, regardless of the caudal-most extent of the low neck target volumes.
Abbreviations: PCs: pharyngeal constrictor muscles, scm: superior constrictor muscle, mcm: middle constrictor muscle, icm: inferior constrictor muscle, GSL: glottic and supraglottic larynx, eim: muscular compartment of the esophagus inlet, NA: not assessed