NEW YORK (Reuters Health) – Combined adjuvant chemotherapy and radiotherapy appear significantly more effective than pelvic radiotherapy alone for women with high-risk endometrial cancer, according to a post hoc analysis of the PORTEC-3 trial.
The study involved 330 women who had been randomly assigned to receive radiotherapy alone and 330 who received radiotherapy along with chemotherapy involving cisplatin, carboplatin AUC5 and paclitaxel.
At a median follow-up of 72.6 months, the five-year overall survival was 81.4% in the chemoradiotherapy group and 76.1% in the radiotherapy alone group (adjusted hazard ratio, 0.70; P=0.034).
For failure-free survival, the rates were 76.5% and 69.1% (HR, 0.70; P=0.016), respectively, Dr. Stephanie M. de Boer of Leiden University Medical Center in the Netherlands and colleagues report in The Lancet Oncology, online July 22.
In a subgroup analysis, the largest failure-free survival benefit with chemoradiotherapy (69% vs. 58%) was observed in women with stage-III disease, who, say the investigators, have a higher baseline risk of recurrence than women with stage I-II disease.
Pelvic control was “excellent” in both groups and distant metastases were the first site of recurrence in most patients with a relapse, with a five-year probability of 21.4% with chemoradiotherapy and 29.1% with radiotherapy alone. This suggests that “new systemic treatment approaches are needed to improve survival outcomes,” the researchers say.
At five years, reported grade-3 adverse events did not differ significantly between the two groups. However, sensory neuropathy persisted more often after chemoradiotherapy, with 6% of this group reporting grade 2 or worse neuropathy at five years compared to none of those given radiotherapy alone.
The researchers conclude that the chemoradiotherapy treatment schedule “should be discussed and recommended especially for women with stage III or serous cancers, or both, as part of shared decision making between doctors and patients.”
In an editorial, Dr. Marcus Randall of the University of Kentucky, in Lexington, notes, “Whether or not the results from PORTEC-3 are generally applicable across patient subgroups remains unknown.”
He concludes that although these and other investigators “have made good progress in improving outcomes for women with high-risk and locally advanced endometrial cancers . . . we are not there yet.”
Dr. de Boer did not respond to requests for comments.
SOURCE: https://bit.ly/2Tte06D and https://bit.ly/2MYIV9O
Lancet Oncol 2019.