Table 1:
Patient, Tumor and treatment characteristics
| Covariate | Full Sample (n=2732) | ORN (No) (n=2508) | ORN (Yes) (n=224) | p-value |
|---|---|---|---|---|
| Insurance Type | <0.001 | |||
| No Insurance | 1160 (42) | 1076 (43) | 84 (38) | |
| Private | 1373 (50) | 1264 (50) | 109 (49) | |
| Public | 199 (7) | 168 (7) | 31 (14) | |
| Teeth-preRT [median (range)] | 25 (1–32) | 25 (1–32) | 25 (2–32) | 0.60 |
| Teeth-PostRT [median (range)] | 24 (0–32) | 24 (0–32) | 23 (0–32) | 0.35 |
| DMFS [median (range)] | 71 (0–160) | 71 (0–160) | 72 (5,160) | 0.86 |
| Smoking | <0.001 | |||
| No | 1925 (70) | 1791 (71) | 134 (60) | |
| Yes | 807 (30) | 717 (29) | 90 (40) | |
| Chemotherapy | 0.28 | |||
| No | 1563 (57) | 1443 (58) | 120 (54) | |
| Yes | 1169 (43) | 1065 (42) | 104 (46) | |
| Surgery | 1 | |||
| No | 1727 (63) | 1585 (63) | 142 (63) | |
| Yes | 1005 (37) | 923 (37) | 82 (37) | |
| Age at Dx [median (range)] | 61.0 (18.3–96.7) | 61.3 (18.3–96.7) | 59.0 (27.7–88.9) | 0.082 |
| Gender | 0.82 | |||
| Female | 732 (27) | 670 (27) | 62 (28) | |
| Male | 2000 (73) | 1838 (73) | 162 (72) | |
| N category | 0.084 | |||
| N0 | 790 (29) | 722 (29) | 68 (30) | |
| N1 | 351 (13) | 324 (13) | 27 (12) | |
| N2 | 1405 (52) | 1282 (52) | 123 (55) | |
| N3 | 156 (6) | 151 (6) | 5 (2) | |
| Missing | 30 | 29 | 1 | |
| Disease Site | <0.001 | |||
| Other | 1074 (39) | 1037 (41) | 37 (17) | |
| Larynx | 199 (7) | 197 (8) | 2 (1) | |
| Lip & Oral Cavity | 490 (18) | 415 (17) | 75 (33) | |
| Oropharynx | 969 (35) | 859 (34) | 110 (49) | |
| Teeth Removed | 0.2 | |||
| Mean (sd) | 1.3 (3.0) | 1.3 (2.9) | 1.7 (3.6) | |
| Median (Min, Max) | 0 (0,28) | 0 (0,26) | 0 (0,28) | |
| Missing | 1 | 1 | 0 | |
| Proportion Teeth Removed | 0.23 | |||
| Mean (sd) | 0.1 (0.2) | 0.1 (0.2) | 0.1 (0.2) | |
| Median (Min, Max) | 0 (0,1) | 0 (0,1) | 0 (0,1) | |
| Missing | 1 | 1 | 0 | |
| Smoking PY [median (range)] | 26 (1–89) | 21 (1–89) | 35 (1–86) | <0.001 |
| PC | 0.012 | |||
| I | 270 (10) | 252 (10) | 18 (8) | |
| II | 504 (19) | 466 (19) | 38 (17) | |
| III | 747 (28) | 673 (27) | 74 (33) | |
| IV | 663 (25) | 596 (24) | 67 (30) | |
| O | 489 (18) | 463 (19) | 26 (12) | |
| Missing | 59 | 58 | 1 | |
| Pre-RT Extraction | 0.3 | |||
| No | 1776 (65) | 1638 (65) | 138 (62) | |
| Yes | 956 (35) | 870 (35) | 86 (38) | |
| RT Dose [median (range)] | 70.0 (2.0–76.7) | 70.0 (2.0–76.7) | 70 (50–70) | 0.16 |
Abbreviations: DMFS: Decayed, missing, filled surfaces according to DMFS160; Pre-RT: before commencement of radiotherapy; post-RT: after completion of radiotherapy; PY: pack-years; PC: Periodontal Condition