Table 2.
The patient, disease, and treatment characteristics.
| Characteristic | C12 Alone, n = 7 No. (%) |
C12 + IMRT, n = 8 No. (%) |
Total, n = 15 No. (%) |
|---|---|---|---|
| median age | 61 years (55–73 years) | 58 years (21–68 years) | 61 years (21–73 years) |
| median follow-up | 22 months (9–48 months) | 24 months (8–61 months) | 24 months (8–61 months) |
| gender | |||
| male | 3 (43) | 4 (50) | 7 (47) |
| female | 4 (57) | 4 (50) | 8 (53) |
| WHO performance status | |||
| 0 | 4 (57) | 4 50 () | 8 (53) |
| 1 | 3 (43) | 3 (38) | 6 (40) |
| 2 | 0 | 1 (12) | 1 (7) |
| tumor type | |||
| ACC | 0 | 8 (100) | 8 (53) |
| CS | 7 (100) | 0 | 7 (47) |
| tumor site | |||
| glottic larynx | 2 (29) | 4 (50) | 7 (47) |
| subglottic larynx | 1 (14) | 0 | 1 (7) |
| supraglottic larynx | 4 (57) | 4 (50) | 7 (47) |
| initial T stage | |||
| T1 | 2 (29) | 1 (12) | 3 (20) |
| T2 | 1 (14) | 1 (12) | 2 (13) |
| T3 | 2 (29) | 0 | 2 (13) |
| T4a | 1 (14) | 5 (63) | 6 (40) |
| T4b | 1 (14) | 1 (12) | 2 (13) |
| initial N stage | |||
| N0 | 7 (100) | 8 (100) | 15 (100) |
| N+ | 0 | 0 | 0 |
| initial M stage | |||
| M1 | 7 (100) | 8 (100) | 15 (100) |
| M0 | 0 | 0 | 0 |
| treatment | |||
| RT only | 3 (43) | 6 (75) | 9 (60) |
| postop. RT | 4 (57) | 2 (25) | 6 (40) |
| total laryngectomy | 0 | 1 (12) | 1 (7) |
| laser surgical resection | 4 (57) | 1 (12) | 5 (33) |
| concomitant cetuximab | 0 | 1 (12) | 1 (7) |
| median EQD2 in Gy | 75 Gy (75–75 Gy) | 76.25 Gy (72.5–80 Gy) | 75 Gy (72.5–80 Gy) |
Abbreviations: C12 = carbon ions, IMRT = intensity-modulated RT, WHO = World Health Organization, ACC = adenoid cystic carcinoma, CS = chondrosarcoma, TNM stage = tumor, nodal, metastasis stage, RT = radiotherapy, postop. = postoperative, EQD2 = equivalent dose to 2 Gy.