Results of study MRC OV05 and EORTC/GCCG 55955 (Rustin et al.) have raised a considerable interest and controversy by questioning the early beginning of recurrent ovarian cancer treatment and the role of Ca 125 monitoring in the follow-up of ovarian cancer patients. Main pitfalls and limitations of this study are introduced in a survey. On their basis an author's opinion on the continuing role of Ca 125 monitoring is expressed with a possible benefit for the subgroup of patients with a solitary or operable relaps or those with new treatment possibilities or with inclusion to new clinical studies.