Parity as a Prognostic Factor in Patients with Advanced-Stage Epithelial Ovarian Cancer

Abstract

Aim: This study aimed to determine the prognostic factors influencing the overall survival (OS) of Iranian women with epithelial ovarian cancer (EOC).

Methods: Information about newly diagnosed patients with confirmed EOC at Motahari Clinic, Shiraz, Iran, from January 1, 2001, to December 31, 2016, was retrospectively reviewed and analyzed. Cox-adjusted proportional hazards (PH) and stratified Cox (SC) models were used to determine the potential prognostic factors.

Results: The mean (±SD) age at the diagnosis of 385 patients with EOC was 49.0 (±13.2) years old. Early-stage EOC (ESEOC) and advanced-stage EOC (ASEOC) were diagnosed in 34.3% and 65.7% of the total patients, respectively. The median (95% CI) OS was 35 (28-41) months. For ESEOC patients, a stage II-tumor led to a lower OS in the multivariable analysis compared to a lower stage tumor (P= 0.025). For ASEOC patients, age≥65 years at diagnosis (P=0.008) led to a lower OS. ASEOC patients with 2-5 parities (P=0.014) and >5 parity (P=0.001) demonstrated better OS than nulliparous women.

Conclusion: Patients with ESEOC, higher tumor stage was associated with a shorter OS. The age at diagnosis harmed the OS of patients with ASEOC. More than one parity improved OS in ASEOC patients.

Keywords: advanced-stage epithelial ovarian cancer; early-stage epithelial ovarian cancer; overall survival; parity; stratified Cox-adjusted regression.

Figure 1

(A) Overall Kaplan-Meier (KM) survival estimates for the study population (^______) and its corresponding 95% confidence intervals (------) [n=385, number of occurred event= 243, Median (95% CI) survival time equals to 35 (28–41) months]; (B) Overall KM survival estimates of early (black, n=132) and advanced (red, n=253) stages EOC patients (Log rank test for equality of survivor functions: Chi-squired statistics=101.5, P<0.0001), Iran, 2001–2016.

Figure 2

Overall non-parametric Kaplan-Meier (KM) survival probabilities of ESEOC patients (n=132, number of occurred event=46): (A) Overall survival (OS) curve of all ESEOC patients [survivor function ^________, 95% confidence intervals -------]; (B) Stages I (black), and II patients (red) [Chi-squired statistics=14.9, P=0.0001] (C) Marriage status: married (black), single (red) [Chi-squired statistics= 4.7, P=0.0301]; (D) Parity: 0 delivery (black), 1 delivery (red), 2 to 5 delivery (green), and > 5 delivery (blue) [Chi-squired statistics=13.7, P=0.0034]; (E) Different age groups at diagnosis age < 45 years (black), 45 ≤ age < 55 years (red), 55 ≤ age < 55 years (green), age ≥ 65 (blue) [Chi-squired statistics=30.2, P<0.0001]; (F) Different histological types: serous carcinoma (black), mucinous carcinoma (red), endometrioid carcinoma (green), and other types (includes: Brenner tumor, clear cell carcinoma, undifferentiated carcinoma) (blue) [Chi-squired statistics=6.0, P=0.1099], Iran, 2001–2016.

Figure 3

Overall non-parametric Kaplan-Meier (KM) survival probabilities of ASEOC patients (n=253, number of occurred event=197): (A) Overall survival (OS) curve of all ASEOC patients [survivor function ^________, 95% confidence intervals -------]; (B) Stages III (black), and IV patients (red) [Chi-squired statistics=3.2, P=0.0734] (C) Marriage status: married (black), single (red) [Chi-squired statistics=0.1, P=0.7090]; (D) Parity: 0 delivery (black), 1 delivery (red), 2 to 5 delivery (green), and > 5 delivery (blue) [Chi-squired statistics=6.2, P=0.1038]; (E) Different age groups at diagnosis age < 45 years (black), 45 ≤ age < 55 years (red), 55 ≤ age < 65 years (green), age ≥ 65 (blue) [Chi-squired statistics=6.3, P=0.0976]; (F) Different histological types: serous carcinoma (black), mucinous carcinoma (red), endometrioid carcinoma (green), and other types (includes: Brenner tumor, clear cell carcinoma, undifferentiated carcinoma) (blue) [Chi-squired statistics=4.1, P=0.2508], Iran, 2001–2016.