The addition of cisplatin to radiation therapy significantly extended DFS among women with stage IIIB squamous cervical cancer, according to study results presented at the ASTRO Annual Meeting.
The regimen also conferred slight improvements in OS, researchers wrote.
The analysis included 147 patients who received high-dose-rate brachytherapy and external-beam radiation in 25 fractions totaling 45 Gy.
Researchers randomly assigned 72 women to receive 40 mg/m2 cisplatin weekly plus pelvic radiation therapy, and the other 75 women underwent radiation therapy alone.
Mean follow-up of 54.9 months.
Women assigned to cisplatin plus radiation demonstrated significantly longer DFS (RR=.52; 95% CI, 0.28-0.98). They also experienced longer OS (RR=.67; 95% CI, .37-1.18), although the difference between arms was not statistically significant.
Researchers noted shorter DFS was associated with a Karnofsky performance score of <90 (RR=2.52; 95% CI, 1.23-4.78), bilateral wall invasion (RR=2.93; 95% CI, 1.21-7.13) and a baseline hemoglobin <10 mg/dL (RR=2.22; 95% CI, 1.01-4.93).
Shorter OS was associated with a Karnofsky performance score <90 (RR=2.75; 95% CI, 1.29-5.87) and hemoglobin <10 mg/dL (RR=2.82; 95% CI, 1.27-6.29).
Researchers reported 37.5% of patients in the cisplatin arm and 28% of patients assigned to radiation alone developed grade 1 or grade 2 acute toxicity (P=.29). Grade 3 or grade 4 late toxicities were observed in 9.7% of patients who received cisplatin and 3% of patients who underwent radiation alone (P=.29).
“In testing a new approach of chemotherapy with traditional external beam radiation therapy and high-dose–rate brachytherapy, we were extremely cautious about possible toxicity for the patients,” researcher Antonio Zuliani, MD, a radiation oncologist at Campinas State University in Brazil, said in a press release. “We believe that these results demonstrate that this combined treatment protocol is safe to offer to patients and provides some beneficial improvements in disease-free survival and toxicity levels.”
For more information:
Zuliani AC. Abstract #8. Presented at: 2013 ASTRO Annual Meeting; Sept. 22-25, 2013; Atlanta.
Disclosure: The researchers report no relevant financial disclosures.