Specimen Handling and Tissue Preparation in Pre-analytical Phase of HER2 Testing at Tertiary Referral Hospitals of Metro Manila, Philippines

Marlowe S. Imperial,1 Susano B. Tanael,1 Jose Ma C. Avila2 and Ma. Lourdes A. Tiambeng3

1Section of Medical Oncology, Department of Medicine, College of Medicine and
Philippine General Hospital, University of the Philippines Manila
2Department of Pathology, College of Medicine, University of the Philippines Manila
3Department of Medicine, Cardinal Santos Medical Center, Mandaluyong City

Introduction. HER2 test result depends on a good quality histological section of the breast specimen. Laboratories that process specimens using sophisticated and molecular testing should receive suitable speciment for more accurate results and less waste of expensive resources.

Methods. A questionnaire based on the ASCO-CAP Guidelines for HER2 testing was developed and administered to pathologists fom the local laboratories of Metro Manila-Philippines tertiary referral hospitals. Questionnaire responses were analyzed using descriptive statistics.

Results. Most laboratories did quality control/quality assessment monitoring for the pre-analytic, analytic, post-analytic and turn-around time phases. Many transported their specimens from the operating room to the laboratory <6 hours but many did not record the duration of fixation. 86% used 10% neutrally-buffered formalin but only 4 laboratories (57%) used the prescribed 10:1 volume to volume ratio of the fixative to the tissue specimen.

Conclusion. Even in standardized procedures, small variations in sample processing for IHC and FISH can still occur. Inexperienced laboratories will have greater problems interpreting HER2 status results. Laboratories should look into their system in handling specimens for an accurate HER2 testing towards quality assurance.

Key Words: specimen handling, tissue preparation, HER2 testing