Table 3 Characteristics of testing set cases for each of the two case-associated methylation classes (rRL and rRRR) relative to those in the other five classes
Methylation class | ||||
|---|---|---|---|---|
Characteristic | rRL (n = 20) | rRRR (n = 13) | All other classes (n = 18) | p difference |
Age, median (range) | 56.5 (29–78) | 54.0 (33–78) | 62.5 (31–76) | 0.43c |
Sex | ||||
Female | 8 (40.0 %) | 2 (15.4 %) | 6 (33.3 %) | 0.33d |
Male | 12 (60.0 %) | 11 (84.6 %) | 12 (66.7 %) | |
Race | ||||
White | 18 (90.0 %) | 11 (84.6 %) | 18 (100 %) | 0.29d |
Other | 2 (10.0 %) | 2 (15.4 %) | 0 | |
Cigarette smokinga | ||||
Never | 7 (38.9 %) | 4 (30.8 %) | 4 (23.5 %) | 0.63d |
Ever | 11 (61.1 %) | 9 (69.2 %) | 13 (76.5 %) | |
Pack-years, median (range) | 16.5 (1.2–48) | 25.0 (5.5–60) | 22.0 (0.9–94) | 0.56c |
Alcohol usea | ||||
Non-drinker | 1 (5.6 %) | 2 (15.4 %) | 0 | 0.21d |
≤2 drinks/day | 10 (55.6 %) | 8 (61.5 %) | 7 (41.2 %) | |
>2 drinks/day | 7 (38.9 %) | 3 (23.1 %) | 10 (58.8 %) | |
HPV serologyb (E6 or E7 antibodies) | ||||
Negative | 12 (66.7 %) | 4 (36.4 %) | 13 (76.5 %) | 0.11d |
Positive | 6 (33.3 %) | 7 (63.6 %) | 4 (23.5 %) | |
Primary tumor site | ||||
Oral cavity | 13 (65.0 %) | 6 (46.2 %) | 10 (55.6 %) | 0.53d |
Oropharynx | 4 (20.0 %) | 6 (46.2 %) | 7 (38.9 %) | |
Hypopharynx | 3 (15.0 %) | 1 (7.7 %) | 1 (5.6 %) | |
AJCC stage group | ||||
Local (stage I or II) | 6 (30.0 %) | 4 (30.8 %) | 10 (55.6 %) | 0.25d |
Advanced (stage III or IV) | 14 (70.0 %) | 9 (69.2 %) | 8 (44.4 %) | |
Tumor size (T class) | ||||
T1–T2 | 14 (70.0 %) | 9 (69.2 %) | 16 (88.9 %) | 0.29d |
T3–T4 | 6 (30.0 %) | 4 (30.8 %) | 2 (11.1 %) | |