Incidence trend of EOC between 1974 and 2013
Total 53,269 patients with EOC were diagnosed among 1974–2013 from original 9 SEER registry sites. The overall incidence of EOC gradually decreased from 11.4 to 9.0 per 100,000 in the four decades. And all age groups also were found to present a similar downward incidence trend, with the most significant decline in the 0–44 age group, which decreased by 33.3%, from 2.4 to 1.8 per 100,000 (Fig. 1a, 1b, Supplementary Table S1).
Over the past four decades, the incidence of EOC in three race subgroups had declined over time. A similar incidence of EOC was observed between Blacks and Others, with Whites having the highest incidence in the past four decades. However, as EOC incidence in Whites declined faster in the four decades, the incidence gaps among the three race subgroups become narrowing (Fig. 1c).
The incidence of EOC had declined in the three subgroups of SES, with the lowest incidence in the high poverty group over the past four decades (from 9.5 in 1974–1983 to 7.1 in 2004–2013). In the past four decades, the low poverty group showed the highest incidence of 11.8, 12.0, 10.7, 9.0 per 100,000 each decade. In addition, the incidence of medium poverty group was between low-poverty group and high-poverty group (Fig. 1e).
Changes Of Relative Survival In Eoc During 1974–2013
Totally 93,639 EOC cases were obtained from 18 SEER sites in the past four decades. There was an improvement in median survival of EOC patients (from 27 months in the first decades to 48 months in the fourth decade) as well as relative survival rate (RSR) and survival time for patients with EOC in the four decades (Table 1, Fig. 2a). The 5-year RSR in 1994–2003 was higher than that in 1984–1993 and 1974–1983 (41.3% in 1994–2003 vs 34.4% in 1984–1993 vs 32.3% in 1974–1983, p < 0.0001), and even higher in 2004–2013 (44.3% vs 41.1%, p < 0.0001) with an significant increase by 37.5% compared to the first decade. The trend of survival improvement was also observed in the RSR of 1 year, 2 year and 10 year. Furthermore, improvement in survival of all age groups was demonstrated by Kaplan-Meier survival analysis with statistical significance over four decades (p < 0.0001; Fig. 2b).
Table 1
Relative survival rates of epithelial ovarian cancer patients during the periods of 1974–1983, 1984–1993, 1994–2003, and 2004–2013 at eighteen SEER sites. Data are mean ± standard error of the mean, with number of patients in parentheses.
Age | | Decade | | |
Group | 1974–1983 | 1984–1993 | 1994–2003 | 2004–2013 |
12-Mo RS | | | | |
All | 63.9 ± 0.5(11521) | 69.8 ± 0.4(14260)*** | 74.7 ± 0.3(27680)*** | 76.8 ± 0.2(40178)*** |
0–44 | 86.0 ± 0.9(1379) | 90.2 ± 0.7(1647)*** | 89.2 ± 0.6(2978)** | 91.0 ± 0.5(3939)*** |
45–54 | 78.2 ± 0.9(2194) | 85.5 ± 0.8(2164)*** | 88.6 ± 0.4(5385)*** | 89.0 ± 0.4(8189)*** |
55–69 | 65.3 ± 0.7(4690) | 75.1 ± 0.6(5377)*** | 81.1 ± 0.4(9226)*** | 83.2 ± 0.3(14848)*** |
70+ | 42.6 ± 0.9(3258) | 50.6 ± 0.7(5075)*** | 57.0 ± 0.5(10091)*** | 57.5 ± 0.5(13202)*** |
24-Mo RS | | | | |
All | 46.6 ± 0.5 | 53.2 ± 0.4*** | 62.4 ± 0.3*** | 65.7 ± 0.3*** |
0–44 | 75.1 ± 1.2 | 80.1 ± 1.0*** | 81.2 ± 0.7*** | 84.9 ± 0.6*** |
45–54 | 58.7 ± 1.1 | 70.1 ± 1.0*** | 77.4 ± 0.6*** | 80.2 ± 0.5*** |
55–69 | 44.5 ± 0.7 | 54.9 ± 0.7*** | 67.4 ± 0.5*** | 71.1 ± 0.4*** |
70+ | 29.0 ± 0.9 | 35.1 ± 0.7*** | 43.8 ± 0.5*** | 44.7 ± 0.5*** |
60-Mo RS | | | | |
All | 32.3 ± 0.5 | 34.4 ± 0.4*** | 41.1 ± 0.3*** | 44.3 ± 0.3*** |
0–44 | 62.1 ± 1.3 | 63.4 ± 1.2 | 64.0 ± 0.9 | 69.7 ± 0.9*** |
45–54 | 41.7 ± 1.1 | 49.2 ± 1.1*** | 55.3 ± 0.7*** | 57.5 ± 0.7*** |
55–69 | 28.3 ± 0.7 | 33.0 ± 0.7*** | 42.3 ± 0.5*** | 46.1 ± 0.5*** |
70+ | 18.2 ± 0.8 | 19.5 ± 0.6 | 24.9 ± 0.5*** | 25.8 ± 0.5*** |
120-Mo RS | | | | |
All | 27.0 ± 0.5 | 27.4 ± 0.4 | 30.8 ± 0.3*** | 34.3 ± 0.4*** |
0–44 | 56.1 ± 1.4 | 56.4 ± 1.2 | 57.0 ± 0.9 | 60.0 ± 1.2*** |
45–54 | 35.6 ± 1.1 | 39.7 ± 1.1*** | 43.0 ± 0.7*** | 45.1 ± 0.9*** |
55–69 | 22.2 ± 0.7 | 33.0 ± 0.7*** | 30.2 ± 0.5*** | 35.1 ± 0.7*** |
70+ | 14.3 ± 0.9 | 15.0 ± 0.7 | 16.9 ± 0.5* | 18.3 ± 0.7*** |
Abbreviations: Mo, month; RS, relative survival; SEM, standard error of the mean. |
*p < 0.01, **p < 0.001, and ***p < 0.0001 for comparisons with the preceding decade. |
Additionally, the survival of all race subgroups improved, with the 5-year RSR of Whites the most significant improvement, increasing by 40.56%, from 31.8 to 44.7 over four decades. In the four decades, the highest survival rate was seen in Others, and Whites showed higher survival compared to Blacks. The 5-year RSR survival difference between Whites and Black widened in 1984–1993 (34.3% vs 28.4%) and greatly become widener in the last two decades (41.3% vs 30.8% in 1994–2003 and 44.7% vs 30.9 in 2004–2013). A similar tendency of survival difference was also observed over time in 10-year RSRs (Fig. 3a, Table 2).
Table 2
12-month, 60-month and 120-month relative survival rates of epithelial ovarian cancer patients according to race, age group, and calendar period from 1974 to 2013 at eighteen SEER sites. Data are means ± standard error of the mean, with number of patients in parentheses.
| | Race |
Decade | Age Group | White | Black | Other |
74–83 | 12-Mo RS | | | |
| All | 64.1 ± 0.5 (10546) | 56.3 ± 2.1 (598)*** | 70.7 ± 2.4 (377)* |
| 0–44 | 86.3 ± 1.0 (1207) | 82.1 ± 3.8 (105) | 86.7 ± 4.2 (67) |
| 45–54 | 78.9 ± 0.9 (1982) | 63.2 ± 4.7 (109)*** | 80.7 ± 3.9 (103) |
| 55–69 | 65.7 ± 0.7 (4301) | 56.2 ± 3.3 (243)** | 70.2 ± 3.8 (146) |
| 70+ | 43.2 ± 0.9 (3056) | 31.6 ± 4.1 (141)** | 37.1 ± 6.3 (61) |
| 60-Mo RS | | | |
| All | 31.8 ± 0.5 | 34.0 ± 2.1 | 40.5 ± 2.6** |
| 0–44 | 60.8 ± 1.4 | 74.1 ± 4.4*** | 65.8 ± 5.9 |
| 45–54 | 42.0 ± 1.1 | 32.0 ± 4.6*** | 46.8 ± 5.0 |
| 55–69 | 28.2 ± 0.7 | 28.7 ± 3.1 | 32.9 ± 4.0 |
| 70+ | 18.4 ± 0.8 | 12.7 ± 0.8 | 19.5 ± 3.4 |
| 120-Mo RS | | | |
| All | 26.7 ± 0.5 | 27.1 ± 2.0 | 34.0 ± 2.6** |
| 0–44 | 54.7 ± 1.5 | 69.3 ± 4.7*** | 60.2 ± 6.1 |
| 45–54 | 35.9 ± 1.1 | 23.7 ± 4.4*** | 41.7 ± 5.0** |
| 55–69 | 22.3 ± 0.7 | 19.3 ± 2.9 | 22.6 ± 3.7 |
| 70+ | 15.2 ± 0.9 | 8.3 ± 3.3*** | 18.5 ± 6.6 |
84–93 | 12-Mo RS | | | |
| All | 70.0 ± 0.4 (12729) | 60.5 ± 1.8 (768)*** | 76.0 ± 1.6 (763)** |
| 0–44 | 90.3 ± 0.8 (1403) | 92.0 ± 2.8 (98) | 87.7 ± 2.7 (146) |
| 45–54 | 86.0 ± 0.8 (1873) | 78.2 ± 3.7 (130)* | 90.1 ± 2.4 (158) |
| 55–69 | 76.1 ± 0.6 (4784) | 57.4 ± 2.9 (295)*** | 77.0 ± 2.5 (298) |
| 70+ | 51.1 ± 0.8 (4669) | 41.7 ± 3.3 (245)*** | 49.4 ± 4.1 (161) |
| 60-Mo RS | | | |
| All | 34.3 ± 0.4 | 28.4 ± 1.8*** | 42.2 ± 1.9*** |
| 0–44 | 63.5 ± 1.3 | 65.9 ± 4.9 | 60.3 ± 4.1 |
| 45–54 | 49.4 ± 1.2 | 41.7 ± 4.5*** | 53.4 ± 4.1 |
| 55–69 | 33.7 ± 0.7 | 18.8 ± 2.4*** | 36.1 ± 2.9 |
| 70+ | 19.4 ± 0.7 | 16.7 ± 2.9 | 25.5 ± 3.8 |
| 120-Mo RS | | | |
| All | 27.2 ± 0.4 | 22.9 ± 1.8 | 35.6 ± 1.9 |
| 0–44 | 56.3 ± 1.4 | 58.4 ± 5.2 | 55.8 ± 4.2 |
| 45–54 | 39.4 ± 1.2 | 34.2 ± 4.4 | 46.2 ± 4.1 |
| 55–69 | 25.6 ± 0.7 | 11.8 ± 2.2*** | 28.3 ± 2.8 |
| 70+ | 14.1 ± 0.7 | 13.2 ± 2.8 | 18.3 ± 3.8 |
94 − 03 | 12-Mo RS | | | |
| All | 75.2 ± 0.3 (23816) | 64.3 ± 1.1 (1892)*** | 79.1 ± 0.9 (1972)*** |
| 0–44 | 90.5 ± 0.6 (2348) | 80.4 ± 2.5 (263)*** | 87.7 ± 1.7 (367) |
| 45–54 | 89.6 ± 0.5 (4496) | 78.5 ± 2.2 (355)*** | 87.6 ± 1.4 (534) |
| 55–69 | 82.3 ± 0.4 (7973) | 65.1 ± 1.9 (639)*** | 81.6 ± 1.6 (623) |
| 70+ | 57.6 ± 0.5 (8999) | 48.9 ± 2.1 (644)*** | 58.5 ± 2.4 (448) |
| 60-Mo RS | | | |
| All | 41.3 ± 0.3 | 30.8 ± 1.1*** | 48.7 ± 1.2*** |
| 0–44 | 65.5 ± 1.0 | 53.1 ± 3.1*** | 61.8 ± 2.6 |
| 45–54 | 56.4 ± 0.8 | 39.7 ± 2.7*** | 56.3 ± 2.2 |
| 55–69 | 42.9 ± 0.6 | 28.4 ± 1.9*** | 49.3 ± 2.1 |
| 70+ | 25.2 ± 0.5 | 18.1 ± 1.8*** | 27.6 ± 2.3*** |
| 120-Mo RS | | | |
| All | 30.7 ± 0.3 | 23.1 ± 1.1*** | 39.4 ± 1.2*** |
| 0–44 | 54.6 ± 1.1 | 44.2 ± 3.2*** | 54.5 ± 2.7 |
| 45–54 | 43.8 ± 0.8 | 29.1 ± 2.6*** | 46.2 ± 2.2 |
| 55–69 | 30.4 ± 0.6 | 19.9 ± 1.8*** | 37.9 ± 2.1*** |
| 70+ | 17.0 ± 0.6 | 12.8 ± 1.9*** | 20.0 ± 2.3 |
04–13 | 12-Mo RS | | | |
| All | 77.3 ± 0.2 (33636) | 65.5 ± 0.9 (3141)*** | 82.0 ± 0.7 (3401)*** |
| 0–44 | 92.3 ± 0.5 (3061) | 80.7 ± 2.2 (329)*** | 89.8 ± 1.3 (549) |
| 45–54 | 89.5 ± 0.4 (6569) | 79.1 ± 1.7 (622)*** | 91.9 ± 0.9 (998) |
| 55–69 | 84.4 ± 0.3 (12501) | 68.8 ± 1.4 (1217)*** | 85.2 ± 1.1 (1130) |
| 70+ | 58.4 ± 0.5 (11505) | 47.4 ± 1.7 (973)*** | 57.6 ± 1.9 (724) |
| 60-Mo RS | | | |
| All | 44.7 ± 0.3 | 30.9 ± 1.1*** | 52.8 ± 1.1*** |
| 0–44 | 71.1 ± 1.0 | 53.1 ± 3.3 *** | 72.2 ± 2.3 |
| 45–54 | 58.6 ± 0.7 | 37.7 ± 2.5*** | 62.6 ± 1.9 |
| 55–69 | 47.0 ± 0.6 | 31.0 ± 1.7*** | 52.4 ± 1.9*** |
| 70+ | 26.6 ± 0.6 | 17.7 ± 1.7*** | 23.8 ± 2.1 |
| 120-Mo RS | | | |
| All | 35.2 ± 0.5 | 22.5 ± 1.3*** | 41.3 ± 1.5*** |
| 0–44 | 60.5 ± 1.4 | 45.8 ± 3.6*** | 60.6 ± 4.0 |
| 45–54 | 45.8 ± 1.0 | 29.0 ± 3.0*** | 51.0 ± 2.9*** |
| 55–69 | 35.5 ± 0.8 | 22.1 ± 2.3*** | 40.5 ± 2.5*** |
| 70+ | 19.2 ± 0.8 | 10.0 ± 2.2*** | 16.2 ± 3.0 |
Abbreviations: Mo, month; RS, relative survival; SEM, standard error of the mean. |
*p < 0.01, **p < 0.001, and ***p < 0.0001 for comparisons with the White group. |
When survival time of SES subgroups was analyzed, it was showed that the RSR of low-poverty group was the highest while that of high-poverty group was the lowest. Over the past four decades, the survival time of all SES subgroups had improved, but over time, the survival gaps between low-poverty group and high-poverty group become widener and widener. For example, in 1984–1993, the 5-year RSR of low-poverty group and high-poverty group was 35.1% vs 32.5% respectively, and the gap between 1994–2003 and 2004–2013 increased to 6.2% and 7.8%. The 10-year RSR was also observed the similar survival difference tendency (Fig. 3b, Supplementary Table S2).
Distributions of SES varied among different races. Most Whites were defined as low-poverty while most Blacks were defined as high- and medium-poverty (Supplementary Figure S1). In fact, the difference in survival between Whites and Blacks partially reflected the difference in survival between various SES subgroups. In the first decade, the median survival of Whites was 27 months higher than that of Blacks for 16 months, and the difference in survival in the fourth decade increased significantly to 18 months (p < 0.0001; Fig. 4a). Similarly, compared with the high-poverty group, the survival advantage of the low-poverty group was found, and the median survival gap kept widening and increased from 7 months to 12 months over time. In addition, Kaplan-Meier survival analysis showed significant differences among three SES subgroups in the past four decades (Fig. 4b).