Factors affecting ovarian cancer survival
Survival following the diagnosis of ovarian cancer appears to be influenced by factors including parity, ovulatory cycles, smoking and body mass index (BMI), a study from Canada has shown.
Researchers examined the medical records of 1,421 patients with invasive epithelial ovarian cancer. A telephone interview was conducted to obtain information on prediagnostic exposure, while the Ontario Cancer Registry was used to determine survival status. Proportional hazards regression analysis was performed to test the association of ovarian cancer-specific mortality with each exposure, and then stratified by histologic subtype to further investigate the associations of risk factors on ovarian cancer-specific mortality.
In the cohort, 46 percent of patients died of ovarian cancer after a mean follow-up of 9.48 years (range, 0.59 to 20.32 years). Among the exposures investigated, parity (ever) was associated with a significant 29-percent reduction in mortality risk compared with nulliparity (hazard ratio [HR], 0.71; 95 percent CI, 0.54 to 0.93; p=0.01). Ever use of oestrogen-containing hormone replacement therapy (HRT) conferred a borderline significant protection against mortality (HR, 0.79; 0.62 to 1.01; p=0.06).
Greater cumulative number of ovulatory cycles was associated with a significant decrease in the risk of ovarian cancer-specific death (HR, 0.63; 0.43 to 0.94; p=0.02).
On the other hand, a history of cigarette smoking was associated with a significant 25-percent increase in the risk of death compared with never smoking (HR, 1.25; 1.01 to 1.54; p=0.04). A higher BMI 5 years before diagnosis also increased the risk of death (HR, 1.17; 1.07 to 1.28; p=0.0007). Other hormonal or lifestyle factors did not show significant associations with ovarian cancer-specific mortality.
Cancer of the ovary is the most serious gynaecologic malignancy and is among the top five leading causes of cancer-related death among women. The prognosis is poor with a mean 5-year survival of 45 percent, and between 15 and 25 percent among patients with advanced (stage III/IV) disease. [Gynecol Oncol 2015;138:750–756]
The current data provide evidence that parity is associated with improved ovarian cancer survival, whereas BMI and smoking are associated with decreased survival. “Once a woman is diagnosed with ovarian cancer, surgical debulking to achieve no residual disease likely has the most impact on her long-term survival,” researchers said.