Women younger than 35 with low-grade serous carcinoma of the ovary or peritoneum or those who still had persistent disease at the completion of primary therapy were found to have worse disease outcomes.
Women aged younger than 35 with a diagnosis of low-grade serous carcinoma of the ovary or peritoneum or those who still had persistent disease at the completion of primary therapy were found to have worse disease outcomes, according to the results of a study looking at these rare cancers.
These results, published by David M. Gershenson, MD, of the University of Texas MD Anderson Cancer Center, and colleagues in the Journal of Clinical Oncology, build on others published in 2006 that defined features of low-grade serous carcinoma of the ovary including a young age at diagnosis, resistance to chemotherapy and prolonged overall survival.
“The principal findings of this study confirm the results of our original publication, indicating that relative to patients with high-grade ovarian or peritoneal cancers, women with low-grade serous carcinoma are younger on average and have prolonged overall survival,” the researchers wrote. “In addition, we found that three factors seemed to have a significant influence on patient outcomes: disease status at completion of primary treatment, age, and primary site of disease.”
The current study looked at 350 women with stage I to IV low-grade serous carcinoma of the ovary or peritoneum diagnosed before January 2012. Gershenson and colleagues looked at progression-free survival and overall survival outcomes.
For the entire group of patients, the median progression-free survival was 28.1 months and the median overall survival was 101.7 months. Those women with low-grade serous carcinoma of the peritoneum had longer progression-free (36.2 vs 25.4 months; P = .02) and overall survival (129 vs 95.2 months; P = .01) compared with women with low-grade serous carcinoma of the ovary. The researchers wrote that “this observation was unexpected, and whether it is real or simply chance remains to be elucidated.”
When the researchers looked at women aged older than 35, they found that these older women had a 43% reduced risk for death compared with women aged 35 or younger (hazard ratio [HR] of 0.53 [95% confidence interval (CI), 0.37–0.74]; P < .001).
At the completion of therapy, 57.3% of patients were disease free. The researchers found that the presence of disease at completion of primary therapy almost doubled the risk for death compared with being clinically disease free (HR, 1.73; P < .001).
The researchers also conducted a subset analysis of women with stage II to IV low-grade serous carcinoma treated with primary surgery followed by platinum-based chemotherapy. In this group, they found that women with low-grade serous carcinoma of the peritoneum had a 41% decreased change of dying (HR, 0.59 [95% CI, 0.36–0.98]; P = .04) compared with women with low-grade serous carcinoma of the ovary.
“This report details information of a large cohort of women with a rare ovarian cancer and is hypothesis generating, potentially leading to advances that will make a difference for women with this condition,” the researchers wrote.