Adjuvant Chemotherapy for Early-stage Ovarian Cancer: Review of the Literature

Purpose: This overview summarizes studies with acceptable quality and validity and presents a synthesis of the effectiveness on adjuvant therapy after surgery for early ovarian cancer (EOC) patients.

Methods: The literature published between 1970 and 2006 was identified systematically by computer-based searches in MEDLINE and Cochrane library.

Results: Twenty-two prospective randomized studies were analyzed, which included 4,626 patients. No difference between adjuvant chemotherapy (AC) and radiotherapy was found. There is agreement on that patients with stage IA, grade 1 tumors have excellent survival and do not need postsurgical therapy. The International Collaborative Ovarian Neoplasm 1/Adjuvant Chemotherapy in Ovarian Neoplasm trials were the first to show an effect on survival of AC, but in patients with adequate surgical staging, there was no additional effect of AC. For patients who are staged incompletely at the time of initial surgery, completion of the staging procedure with either laparoscopy or laparotomy is a reasonable approach before a final decision is made regarding the need for AC. If full staging cannot be performed due to medical contraindication or patient refusal, consideration of AC is reasonable in selected patients. Using prognostic variables such as grade, International Federation of Gynecology and Obstetrics substage, pretreatment of CA-125 < or = 30 U/mL, and DNA ploidy, it is possible to divide patients into risk groups to avoid overtreatment. Gynecologic Oncology Group study 157 suggests that it may be possible to minimize chemotherapy-induced toxicity by using three instead of six cycles of AC, although it is not known fully whether this will compromise effectiveness.

Conclusion: Future randomized studies in EOC will include the investigation of new targeted therapies and new prognostic factors in adequately staged patients.