A National Quality Assurance program for breast immunohistochemistry: an Italian perspective

Area of Science:

• Pathology
• Oncology
• Quality Assurance

Background:

• Breast cancer diagnosis relies heavily on immunohistochemistry (IHC) for hormone receptors (ER, PR) and HER2.
• Standardized quality assessment is crucial for reliable IHC results in clinical practice.
• A national project was initiated in Italy to evaluate the quality of breast cancer IHC.

Purpose of the Study:

• To assess the general performance of breast cancer immunohistochemistry (ER, PR, HER2) in Italian pathology laboratories.
• To identify any differences in IHC quality across Italian regions and laboratory types.
• To explore the potential benefits of a mandatory national quality control program for IHC.

Main Methods:

• A national quality assessment project involving 155 Italian pathology laboratories.
• Proficiency testing conducted by the Nordic Immunohistochemical Quality Control (NordiQC) organization.
• Analysis of epidemiological and geographical distribution data alongside NordiQC results.

Main Results:

• Italian IHC quality data were consistent with official NordiQC assessments for ER, PR, and HER2.
• An 80% consensus on HER2 scoring was achieved between participating laboratories and the assessor group.
• No substantial differences in IHC quality were found across Italian macro-areas (North, Center, South) or between high-volume (>100 tests/year) and low-volume laboratories.

Conclusions:

• The national quality assessment project demonstrated a high and consistent standard of breast cancer IHC across Italy.
• The findings support the feasibility and potential value of a mandatory national quality control program within the Italian National Health Care System.
• Geographical location and testing volume do not appear to be significant factors influencing breast cancer IHC quality in Italy.