Five factors identify subset of patients with advanced cervical cancer who may not benefit from bevacizumab treatment

Patients with advanced cervical cancer who were at intermediate and high risk of poor outcome, as assessed by the Moore criteria, gained survival benefit from having bevacizumab added to their chemotherapy regimen while those at low risk of poor outcome did not, according to results of a major objective of the phase III NRG Oncology-Gynecologic Oncology Group protocol 240 (GOG 240) clinical trial published in Clinical Cancer Research, a journal of the American Association for Cancer Research.

"The Moore criteria are five clinical factors that have been proposed to be prognostic for poor outcomes among patients with advanced cervical cancer," said Krishnansu S. Tewari, MD, professor and director of research in the Division of Gynecologic Oncology at the University of California, Irvine. "The factors are being of African-American ancestry and having a performance status of 1, pelvic disease, prior platinum-based treatment, and progression-free survival of less than one year. Patients who have zero or one negative prognostic factor are proposed to be at the lowest risk for poor outcome, those with two or three at intermediate risk, and those with four or five at high risk.

"Our study prospectively validates the Moore criteria as prognostic for outcome among patients with advanced cervical cancer and identifies a population, those at low risk for poor outcome, who are unlikely to gain benefit from treatment with bevacizumab," added Tewari. "Therefore, the Moore criteria represent the first prospectively validated scoring system in cervical cancer. They provide oncologists with a clinical instrument to help them counsel patients and their families regarding anticipated outcomes and the potential benefit, or lack of benefit, of adding the recently approved cervical cancer drug, bevacizumab, to standard chemotherapy."

Previously published results from the GOG 240 phase III clinical trial showed that adding bevacizumab to chemotherapy increased overall and progression-free survival for patients with advanced cervical cancer and led to the approval of bevacizumab for use in this way by the U.S. Food and Drug Administration.

Tewari explained that this new study reports on a second major objective of GOG 240, which was to prospectively assess the validity of the previously identified factors prognostic of poor outcome (the Moore criteria) and, if the criteria were validated, to ask whether they could be used to guide treatment decisions by identifying patients who may not benefit from bevacizumab, which can cause serious adverse side effects.

The researchers found that among all 452 patients on the study, the difference in overall survival was significantly different depending on the different Moore criteria risk categories: median overall survival was 21.8 months among those in the low-risk category, 14.7 for those in the intermediate-risk category, and 8.2 months for those in the high-risk category.

Further analysis showed that for patients who were in the low-risk Moore category, there was not a statistically significant difference in median overall survival among those assigned chemotherapy alone and those assigned chemotherapy and bevacizumab (21.8 months versus 22.9 months). There was a statistically significant difference in median overall survival for patients in the intermediate- and high-risk Moore categories, with bevacizumab extending median overall survival by almost six months, from 12.1 to 17.9 months for those in the intermediate-risk category and from 6.3 to 12.1 months for those in the high-risk category.

According to Tewari, one limitation of the study could be perceived to be the lack of applicability of the Moore criteria to populations that do not include African-Americans. He went on to say that, "However, we believe that African-Americans are a surrogate for lack of access to health care because there are studies that show the clinical outcomes of African-American patients with cervical cancer are similar to non-African Americans when the health care access playing field is level."