At the 2022 San Antonio Breast Cancer Symposium, Per Karlsson, MD, PhD, Sahlgrenska Comprehensive Cancer Center, Gothenburg, Sweden, presents results from the meta-analysis investigating the prognostic value of the Profile for the Omission of Local Adjuvant Radiotherapy (POLAR) in predicting the benefit of radiotherapy for patients with breast cancer.

As Dr Karlsson noted, these results must be further validated before they are ready for clinical practice, but they show POLAR as the first genomic classifier to predict radiotherapy benefit.

Transcript

My name is Per Karlsson. I'm a professor of oncology in Sweden. I work at the Sahlgrenska Comprehensive Cancer Center at the Department of Oncology. I'm here in San Antonio, and I will present data regarding a patient-level meta-analysis with the objective to analyze the ability of the POLAR score to predict the benefit of breast radiotherapy. We have in the SweBCG91-RT trial developed a score, and we have collected all the blocks from randomized trials where patients have had radiotherapy or no radiotherapy after breast-conserving surgery. We have long-term follow-up in that study, and that's what we are going to present.

The patient-level meta-analysis includes 3 different randomized studies: the Swedish trial, SweBCG91-RT, as well as the Princess Margaret trial and the Scottish Conservation Trial. The objective was to see if the POLAR score could prognosticate locoregional recurrences in the new radiotherapy arms and further to see if the POLAR score can predict radiation benefits. We have just done this in the hormone receptor-positive, HER2-negative subgroup with the node-negative patients.

We have seen here that the POLAR score can prognosticate locoregional recurrences in the new radiotherapy arms in all 3 of these different studies. Further, we have seen that the interaction between the POLAR score and radiotherapy is statistically significant, indicating that this is a predictive assay for radiotherapy benefit.

We think these are interesting results, but it is retrospective data from prospective randomized trials. We need to go further and validate the results before it can enter a clinical practice. Thus far, this is the first genomic classifier that can predict radiotherapy benefit, so we think this is interesting for the future.

Source:

Karlsson P, Fyles A, Chang SL, et al. “Validation of Profile for the Omission of Local Adjuvant Radiotherapy (POLAR) in a meta-analysis of three randomized controlled trials of breast conserving surgery +/- radiotherapy.” Presented at San Antonio Breast Cancer Symposium; December 6-10, 2022; San Antonio, Texas. Abstract GS4-03