A) Control mice received no surgical intervention. Treated mice received a hysterectomy and bilateral salpingo-oophorectomy at either 6- or 10-weeks after tumor inoculation. Without cytoreductive surgery mice lived for a median of 205 days (n=10). After late (10 week) cytoreductive surgery, there was an intermediate survival of a median of 241 days (n=6; p=0.1443 compared to no surgery control). After early (6 week) cytoreductive surgery, mice experienced the longest survival, with a median of 360 days (n=15; p=0.0107 compared to no surgery control). Black dash in the 6-week cohort indicates when a group of mice was censored from the study. Statistical analysis performed using a Log-rank Mantel-Cox test. IHC for B) CD8 or C) FoxP3 was performed on metastatic tumor samples from mice that did not receive cytoreductive surgery (white box, n=9) or that received 6-week cytoreductive surgery (gray box, n=11–12). Statistical analysis performed using an unpaired student’s t-test.