Only 20-40% of patients with advanced ovarian cancer have no residual disease after primary cytoreductive surgery. For patients with residual tumor and good response to chemotherapy new therapeutic procedures have to be discussed. In our study the role of secondary debulking surgery, especially after G-CSF supplied dose intensification was evaluated. Between January 1986 and December 1995, 506 patients with primary ovarian cancer were treated at our institution. 117 patients with residual tumor after primary surgery had secondary debulking after four to six cycles of platinum based chemotherapy, 26 of them had G-CSF supplemented dose intensification by shortened therapy intervals. After secondary debulking 43% had no residual disease, 37% had residual tumor less than 2 cm and 20% more than 2 cm. Mean survival in patients without residual disease was 47 months and significantly longer than in patients without secondary debulking with only 35 months. In 25 to 26 patients with dose intensification chemotherapy cycles could be applied regularly, the results were in the expected range. Secondary debulking surgery can prolong survival in those patients without residual tumor after secondary surgery. Dose intensification is possible without remarkable side effects. In our study the percentage of patients without residual tumor could not be increased by dose intensification.