Table 3. Survival and risk of recurrence for II as compared to stage I endometrial cancer after stratification into risk group according to risk factors (grade, myometrial invasion, unfavorable tumor types). Two adjusted Cox comparisons were performed 1. Intermediate- or high-risk were compared to low-risk (2 right columns) and 2. Stage II with uterine low-, intermediate- and high-risk features were compared to corresponding risk groups of stage I to evaluate whether cervical invasion in itself is a risk factor (Differences marked with ‡).
| Variables | All | Uterine risk group | HR (95% CI) Compared to low-risk | |||||
|---|---|---|---|---|---|---|---|---|
| Low-risk | Intermediate-risk | High-risk | Intermediate-risk | High-risk | ||||
| Stage I | 3,426 | 2,247 | 873 | 306 | ||||
| 5-year survival | ||||||||
| OS | 86 (85–87) | 91 (89–92) | 82 (80–85) | 65 (59–70) | 1.49* (1.19–1.86) | 3.37* (2.55–4.47) | ||
| Cancer-specific survival | 95 (94–95) | 97 (96–98) | 94 (92–95) | 79 (74–83) | 1.49 (0.84–2.67) | 6.13* (3.74–10.07) | ||
| Recurrence-free survival | 90 (89–91) | 94 (93–95) | 85 (82–87) | 73 (68–78) | 2.20* (1.69–2.86) | 4.41* (3.13–6.22) | ||
| Actuarial recurrences <5 years | ||||||||
| Locoregional recurrences | 7.1 (6.3–8.1) | 4.9 (4.1–5.9) | 10.8 (8.8–13.1) | 14.3 (10.6–19.0) | 1.98* (1.46–2.68) | 3.19* (2.07–4.91) | ||
| Non locoregional recurrences | 5.6 (4.9–6.5) | 2.5 (1.9–3.3) | 8.1 (6.4–10.2) | 22.9 (18.4–28.3) | 2.85* (1.94–4.20) | 8.83* (5.63–13.8) | ||
| Pelvic or paraaortic LN recurrences | 2.8 (2.3–3.5) | 1.2 (0.8–1.8) | 4.5 (3.3–6.2) | 11.1 (7.8–15.6) | 3.09* (1.77–5.37) | 7.71* (4.01–14.8) | ||
| Non-local LN recurrences | 1.3 (0.9–1.7) | 0.6 (0.3–1.0) | 2.0 (1.2–3.3) | 5.5 (3.2–9.3) | 3.20† (1.41–7.30) | 7.21* (2.66–19.6) | ||
| Stage II | 461 | 158 (34.3) | 208 (45.1) | 95 (20.6) | ||||
| 5-year survival | ||||||||
| OS | 74‡ (70–78) | 92 (86–95) | 70‡ (63–75) | 53 (43–63) | 3.99* (2.18–7.30) | 7.72* (4.01–14.9) | ||
| Cancer specific-survival | 84‡ (80–87) | 96 (92–98) | 82‡ (76–87) | 66§ (55–75) | 4.97* (2.07–12.0) | 12.5* (5.00–31.5) | ||
| Recurrence free-survival | 76‡ (72–80) | 90§ (85–94) | 73‡ (66–79) | 58§ (47–68) | 3.03* (1.69–5.45) | 6.39* (3.34–12.2) | ||
| Actuarial recurrences <5 years | ||||||||
| Locoregional recurrences | 17.9‡ (14.6–21.9) | 8.9§ (5.4–14.6) | 20.1‡ (15.0–26.6) | 30.7‡ (21.8–42.2) | 2.35† (1.24–4.43) | 4.77* (2.32–9.79) | ||
| Non locoregional recurrences | 15.4‡ (12.2–19.2) | 3.3 (1.4–7.8) | 19.7‡ (14.6–26.3) | 27.9 (19.4–39.1) | 6.54* (2.53–16.9) | 11.9* (4.32–33.0) | ||
| Pelvic or paraaortic LN recurrences | 9.9‡ (7.4–13.3) | 2.0 (0.6–6.2) | 14.9‡ (10.4–21.0) | 13.4 (7.4–23.7) | 7.96* (2.37–26.7) | 7.34† (1.88–28.6) | ||
| Non-local LN recurrences | 2.5 (1.4–4.7) | 0.7 (0.1–4.7) | 3.5 (1.6–7.7) | 3.8 (1.2–11.5) | 5.42 (0.63–46.8) | 9.21 (0.82–103.8) | ||
Survival is given as % (95% CI) and risk of recurrence is given as actuarial recurrences rate in % (95% CI).
aHR is represented adjusted for significant or potential confounders by multivariate analysis including, age, American Society of Anesthesiologists, grade, type of hysterectomy, lymph node resection, adjuvant EBRT or chemotherapy. Cox was not adjusted for grades 1, 2, 3, unfavorable tumor types when evaluating risk groups as this confounder is also represented in the risk groups.
aHR, adjusted hazard ratio; CI, confidence interval; EBRT, external beam radiotherapy; HR, hazard ratio; OS, overall survival.
*p<0.001, †p<0.05: aHR testing intermediate- or high-risk against low-risk; ‡p<0.001, §p<0.05: aHR testing risk group stage II against corresponding to risk group stage I.