Table 3.
Risk for second esophageal cancer by follow-up interval after the diagnosis of oral/pharyngeal cancer.
| First primary cancer site (ICD-9) | Follow-up time (yrs) | OPY | O | E | SIR (O/E) |
95% CI |
|---|---|---|---|---|---|---|
| Oral cavity (140-1,143-145) |
≤1 | 10352 | 34 | 1.87 | 18.18 | (12.62-25.47) |
| 1-5 | 25205 | 45 | 4.91 | 9.16 | (6.69-12.27) | |
| > 5 | 55087 | 20 | 10.96 | 1.82 | (1.11--2.82) | |
| Oropharynx (146, 149) |
≤1 | 1449 | 21 | 0.28 | 75.00 | (47.12-116.41) |
| 1-5 | 2862 | 9 | 0.53 | 17.31 | (7.83-32.56) | |
| > 5 | 6992 | 0 | 1.30 | 0 | (NA) | |
| Hypopharynx (148) |
≤1 | 2119 | 43 | 0.53 | 81.13 | (59.57-110.88) |
| 1-5 | 3005 | 20 | 0.77 | 25.97 | (15.76-39.87) | |
| > 5 | 6088 | 8 | 1.82 | 4.40 | (1.89 -- 8.66) |
Bold indicates statistical significance.
OPY = observed person years; SIR = standardized incidence ratio; O = observed numbers of second esophageal cancer; E = expected numbers of second esophageal cancer; CI = confidence interval;
NA = not assessable; yrs = years.