Hormonal maintenance therapy prolongs PFS for serous carcinoma of ovary, peritoneum
Women with stage II to stage IV low-grade serous carcinoma of the ovary or peritoneum demonstrated longer PFS when treated with hormonal maintenance therapy after primary chemotherapy rather than routine observation, according to results of a retrospective study.
“The findings of this study are potentially practice changing and warrant a prospective randomized trial for confirmation,” David M. Gershenson, MD, professor in the department of gynecologic oncology and reproductive medicine at The University of Texas MD Anderson Cancer Center and a HemOnc Today Editorial Board member, told HemOnc Today. “Such a trial, which has already been discussed with our international partners, is currently under development.”
Gershenson and colleagues used the Low-Grade Serous Tumor Database to evaluate data from 203 women with low-grade serous carcinoma of the ovary or peritoneum seen at MD Anderson between 1981 and 2013. Of these, 133 underwent routine observation and 70 received hormonal maintenance therapy. Patients who underwent hormonal maintenance received letrozole (n = 38), tamoxifen (n = 20), leuprolide (n = 5), anastrozole (n = 2), leuprolide acetate with either letrozole or tamoxifen (n = 2 each), and depot medroxyprogesterone acetate (n = 1).
The researchers examined differences between clinical outcomes associated with hormonal maintenance therapy compared with routine observation after primary cytoreductive surgery and platinum-based chemotherapy.
“Because low-grade serous carcinoma of the ovary or peritoneum is relatively chemotherapy resistant compared with the more typical high-grade subtypes, there is a search for more effective therapies, including targeted agents and hormonal drugs,” Gershenson said.
Median follow-up was 70.8 months for the entire cohort, 80.3 months for patients who underwent routine observation and 54.9 months for patients who received hormonal maintenance therapy.
Median PFS was 32.6 months for the entire cohort (95% CI, 28.4-36.9) and was significantly higher among patients who received hormonal maintenance therapy (64.9 months vs. 26.4 months; P < .001). Overall, hormonal maintenance therapy lowered risk for disease progression compared with routine observation (HR = 0.44; 95% CI, 0.31-0.64).
Median OS for the entire cohort was 104.7 months (95% CI, 75.1-134.3). Researchers observed no statistically significant difference in OS between patients who underwent routine observation and hormonal maintenance therapy (102.7 months vs. 115.7 months).
Subgroup analyses showed median PFS also was higher with hormonal maintenance therapy compared with routine observation among women who were disease free (81.1 months vs. 30 months; P < .001) or had persistent disease (38.1 months vs. 15.2 months; P < .001).
Multivariate analysis showed hormonal maintenance therapy, age older than 35 years, stage and primary peritoneal tumor were associated with a lower likelihood of disease progression. Factors associated with lower risk for mortality were stage, age older than 35 years and disease-free status after primary chemotherapy.
“The findings of this database study indicate a very significant advantage in terms of PFS for hormonal maintenance therapy versus observation in women with [stage II to stage IV] low-grade serous carcinoma who have undergone primary surgery followed by platinum/taxane chemotherapy,” Gershenson said. – by Melinda Stevens
For more information:
David M. Gershenson, MD, can be reached at Department of gynecologic Oncology and Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Unit 1362, 1155 Pressler Drive, Houston, TX 77030; email: firstname.lastname@example.org.
Disclosure: Gershenson reports stock or other ownership with AbbVie, Biogen, Celgene, GlaxoSmithKline, Johnson & Johnson, Merck and Pfizer; a consultant role with Clovis Oncology, and royalties from Elsevier and UpToDate. Please see the full study for a list of all other researchers’ relevant financial disclosures.