Validation of Referral Guidelines for Women with Pelvic Masses

Abstract & Commentary

Synopsis: The SGO and ACOG referral guidelines effectively separate women with pelvic masses into 2 risk categories for malignancy. This distinction permits a rational approach for referring high-risk patients to a gynecologic oncologist for management.

Source: Im SS, et al. Obstet Gynecol. 2005;105:35-41.

In 2002, the American College of Obstetricians and Gynecologists (ACOG) and the Society of Gynecologic Oncologists (SGO) jointly published referral guidelines for women with pelvic masses suspicious for ovarian cancers. Although intuitive and uncomplicated, the guidelines have not been validated. The current report by Im and colleagues aimed to retrospectively evaluate the guidelines for accuracy and to determine if modification should be implemented to more accurately identify at-risk women. Im et al identified 1035 women undergoing surgery for a pelvic mass of whom 318 had primary malignancy of the ovary, fallopian tube, or peritoneum. Since the guidelines are dichotomized by menopausal status, validation was addressed in both groups, individually. Not unexpectedly, the guidelines produced a higher predictive value for cancer in postmenopausal women where the prevalence of disease is significantly higher. Negative predictive value was high (> 90%) in both cohorts and while the guidelines would have dictated a significant number of benign disease referrals (31%-42%) to a gynecologic oncologist, very few bona fide cancer were missed. The single most reliable predictor of cancer in list was the CA-125 level; the least was family history. Im et al concluded that, as intended, the guidelines successfully fulfill their goal in identifying "high-risk for cancer" individuals. However, continued evaluation and modification is warranted to improve their precision.

Comment by Robert L. Coleman, MD

While published specific guidelines for clinical care can be both helpful and problematic, they are predominately constructed in the spirit of providing intuitive and evidence-based triage for important and relevant clinical issues. The current guidelines regarding referral (to a gynecologic oncologist) for pelvic/adnexal mass were jointly developed and published by ACOG and SGO in an attempt to identify high-risk individuals who, on the identification of malignancy would have appropriate staging/debulking procedures. The evidence to support the benefit of performing appropriate intraoperative procedures in these uncommon situations is mounting, but is consistent among the few reported series comparing outcomes based on surgeon type. The guidelines also, when successful, remove a clinical dilemma regarding therapy when an unstaged or undebulked patient is referred postoperatively. The evidence to support a benefit to patients in this setting is also mounting. For example, in the case of an unstaged patient, there are, in essence, 3 options to consider. In the first, a formal staging laparotomy can be performed. If the patient has undergone a transverse incision, an extension of this incision may allow for upper abdominal exposure; however, frequently a vertical incision will need to be made to ensure adequate sampling. Laparoscopic re-staging is an alternative for selected patients but it has not been formally validated against open staging for ovarian malignancies. Nonetheless, data from this second operation will be important in discussions of adjuvant therapy.1

An alternative option would be to assume other metastatic disease is present and initiate combination cytotoxic chemotherapy. It is well documented that metastatic disease will be identified in approximately 30% of patients who undergo restaging. This maneuver would spare a second operation for the patients but potentially over-treat a large proportion of individuals (not 70% because some of the non-metastatic cases would be candidate for chemotherapy as well).2 The third option, of course, would be expectant close observation. In this setting, given the data above, there is a real potential for under-treatment. Hedging our bets with surrogate biomarkers, computed tomography (CT), magnetic resonance imaging (MRI) and positron emission tomography (PET) we hopefully will identify the best candidates for this option. However, accurate and reliable screening for recurrent disease is not yet available and it has been recently documented that when these observed patients undergo expectant care without formal staging, the distribution of disease at recurrence is no different than a typical Stage III patient—that is, with widely metastatic abdominal disease.3 Chance for cure in this setting is low. The guidelines appear to over-refer benign patients but, more importantly, few cancers are missed.

Im et al also suggest a modification to the guide lines in reflection of their multivariate analysis. In this revision menopausal status, presence of ascites, evidence of metastatic disease and CA125 (> 50 U/mL, pre-menopausal, > 35 U/mL menopausal) were included. It is anticipated that as more data are generated and new biomarkers evaluated the guidelines will better achieve what they were initially set out to do.

References

1. Vergote I, Trimbos BJ. Curr Opin Oncol. 2003;15(6):452-455.

2. Le T, et al. Gynecol Oncol. 2002;85(2):351-355.

3. Kolomainen DF, et al. J Clin Oncol. 2003;21(16): 3113-3118.

Robert L. Coleman, MD, Associate Professor, University of Texas; M.D. Anderson Cancer Center, Houston Texas is Associate Editor for OB/GYN Clinical Alert.