A randomized trial was performed to determine whether screening women with ovarian cancer in clinical remission for serum levels of a tumor marker every 3 months, followed by treatment of recurrences identified through this means, could reduce mortality. Women were recruited into the trial at the onset of the remission induced by their initial treatment.

Those who later were found to have elevated levels of the marker were randomized to one of two approaches to management:

(a) Immediate chemotherapy; or

(b) No additional treatment until the recurrence became apparent for other reasons (typically, the development of symptoms), on average 5 months later. (Values for serum levels of the tumor marker in patients in group (b) were not provided to these women’s physicians.)