Partial breast irradiation: targeting volume or breast molecular subtypes?

Area of Science:

• Oncology
• Radiotherapy
• Breast Cancer Research

Background:

• Current eligibility criteria for accelerated partial breast irradiation (APBI) rely heavily on histopathological factors, which do not consistently predict breast cancer clinical behavior.
• International guidelines offer a framework for refining patient selection for APBI, but their application to APBI cohorts reveals limitations, especially for intermediate and high-risk patients.
• The variability in APBI techniques and breast cancer subtypes complicates clinical results, affecting the predictive power of histopathological factors.

Purpose of the Study:

• To highlight the need for improved risk stratification in APBI patient selection.
• To investigate the role of breast cancer subtype in local control after APBI.
• To explore the potential of molecular classification to enhance conventional prognostic factors.

Main Methods:

• Review of existing literature and clinical guidelines for APBI patient selection.
• Analysis of factors influencing local control in APBI series.
• Discussion on the integration of molecular subtypes into treatment decision-making.

Main Results:

• Histopathological factors alone are insufficient for optimal patient selection in APBI.
• The impact of breast cancer subtype on local recurrence requires further investigation.
• Molecular classification shows promise in refining risk prediction beyond traditional factors.

Conclusions:

• There is a critical need to refine and implement additional risk factors for APBI.
• Radiotherapy decisions for breast cancer should increasingly consider molecular subtype.
• Molecular classification is expected to add significant value to conventional characteristics in predicting local recurrence and patient outcomes.