Adjuvant chemotherapy does not improve mortality in locally advanced cervical cancer

Article written by Bruce Sylvester.

In locally advanced cervical cancer, use of adjuvant chemotherapy after standard chemoradiation does not improve mortality outcomes.

Researchers reported this finding on June 3, 2021 at the American Society of Clinical Oncology/ ASCO Virtual Annual Meeting.

“This trial provides clear evidence that the addition of chemotherapy after chemoradiation does not extend survival. The results are immediately practice-changing, showing that this approach should not be used to treat locally advanced cervical cancer. We can now spare our patients the side effects and toxicity that comes with additional chemotherapy,” said ASCO President Lori J. Pierce, MD, Professor in Radiation Oncology at the University of Michigan in Ann Arbor. 

As background, the authors noted that cervical cancer is a common cause of cancer-related death among women. And while standard treatment for locally advanced disease is chemoradiation (cisplatin-based chemotherapy concurrent with radiation), a significant percentage of patients  relapse and die from the development of distant metastatic disease.

The OUTBACK trial was designed to determine the effects on survival of adjuvant chemotherapy (carboplatin and paclitaxel chemotherapy) after chemoradiation.

The investigators enrolled 926 subjects and randomized them to either standard cisplatin-based chemoradiation or standard chemoradiation followed by adjuvant chemotherapy with 4 cycles of carboplatin and paclitaxel.

The primary end point was overall survival at 5 years. Secondary endpoints included progression-free survival.

They reported that 919 of 926 women recruited from April 2011 to June 2017 were eligible and included in the primary analysis, with 463 assigned adjuvant chemotherapy and 456 assigned standard therapy only.

At 5 years, overall survival was comparable for both groups —  72% vs. 71%, respectively, for subjects assigned to additional adjuvant chemotherapy and for those receiving standard care.  The difference was not statistically significant.

There was no recurrence of disease in 63% of subjects who received adjuvant chemotherapy, compared with 61% who received chemoradiation only. The difference was not statistically significant.

The authors noted, “More serious adverse events (grade 3-5) were experienced by 81% of patients who received additional chemotherapy, versus 62% in the standard treatment group up to 1 year following randomization.”

The authors concluded, “Adjuvant chemotherapy given after standard cisplatin-based chemoradiation for women with locally advanced cervical cancer did not improve OS [overall survival] or PFS [progression-free survival].”