Dr Maurie Markman's comments: re: CA125/survival ASCO....

Cancerwise | A blog featuring Cancer News and Insights from M. D. Anderson


Surveillance of CA-125 in Women With Advanced Ovarian Cancer
By Cancerwise Blogger on June 2, 2009 9:34 AM
By Maurie Markman, M.D., Vice President for Clinical Research, from ASCO 2009

The abstract from Rustin, et al, dealing with the clinical utility of routine surveillance of CA-125 in women with advanced ovarian cancer who attain a complete clinical remission following cytotoxic chemotherapy has the potential to change the standard management paradigm in this clinical setting.

This well-designed and conducted Phase III randomized trial revealed that patients who initiated treatment for recurrent disease solely based on an elevated CA-125 antigen (in the complete absence of any signs or symptoms of cancer) did not experience superior survival compared to women who experienced recurrence but whose therapy was started due to other manifestations of the malignancy (for example, a return of abdominal symptoms).

However, it is critically important to recognize what this study does not state.

First, there is no statement that patients treated in this trial failed to experience benefit from the treatment of recurrence, but only that it was possible to delay reintroduction of treatment until symptoms developed.

Second, there is no statement that CA-125 should be avoided in a patient who experiences symptoms. In fact, in this setting, a serum CA-125 level can be particularly helpful since symptoms of recurrent ovarian cancer can be quite non-specific. In a woman who has previously undergone a major abdominal surgical procedure, interference with bowel function (often due to adhesions) can appear to be due to progressive cancer when in reality the discomfort is secondary to the effects of the previous surgery.

The finding of a normal CA-125 antigen level in this situation can be helpful, while an elevated value would likely lead to future investigation (e.g., abdominal/pelvic CT scan) and possible re-introduction of anti-neoplastic treatment.