CONFIRM ANTI-ESTROGEN RECEPTOR ER SP1

Additional Manufacturer Narrative

THE SERIAL NUMBER OF THE CUSTOMER'S BENCHMARK ULTRA STAINER MODULE IS 322081. THE COMPETITOR PLATFORM CLONES ARE AGILENT EP1 AND LEICA 6F11. PER THE USE INSTRUCTIONS FOR THE OTHER PRODUCTS USED, LEICA¿S MOUSE MONOCLONAL "CLONE 6F11 IS RAISED TO THE FULL LENGTH ALPHA FORM OF THE ESTROGEN RECEPTOR MOLECULE" AND "FALSE-POSITIVE RESULTS MAY BE SEEN DUE TO NON-IMMUNOLOGICAL BINDING OF PROTEINS OR SUBSTRATE REACTION PRODUCTS." AGILENT¿S MONOCLONAL RABBIT CLONE EP1 "IS A RECOMBINANT PROTEIN OF ER AMINO ACIDS 1-300". THE DIFFERENCES IN THE CLONES AND THEIR DESIGN FOR BINDING MAY RESULT IN SAMPLE-SPECIFIC DIFFERENCES IN DETECTION OF THE ER. PER PRODUCT LABELING FOR THE CONFIRM ANTI-ESTROGEN RECEPTOR ER SP1: "CONFIRM ANTI-ER (SP1) ANTIBODY IS DIRECTED AGAINST AN EPITOPE PRESENT ON HUMAN ER ALPHA PROTEIN LOCATED IN THE NUCLEUS OF ER POSITIVE NORMAL AND NEOPLASTIC CELLS." PRODUCT LABELING FOR THE CONFIRM ANTI-ESTROGEN RECEPTOR ER SP1 ALSO STATES THE FOLLOWING: "REAGENTS MAY DEMONSTRATE UNEXPECTED REACTIONS IN PREVIOUSLY UNTESTED TISSUES. THE POSSIBILITY OF UNEXPECTED REACTIONS EVEN IN TESTED TISSUE GROUPS CANNOT BE COMPLETELY ELIMINATED BECAUSE OF BIOLOGICAL VARIABILITY OF ANTIGEN EXPRESSION IN NEOPLASMS, OR OTHER PATHOLOGICAL TISSUES." "AS WITH ANY IHC TEST, A NEGATIVE RESULT MEANS THAT THE ANTIGEN WAS NOT DETECTED, NOT THAT THE ANTIGEN WAS ABSENT IN THE CELLS OR TISSUE ASSAYED." IT IS ALSO IMPORTANT TO NOTE THAT THE ASSESSMENT FOR POSITIVITY FOR ESTROGEN RECEPTOR (SP1) IS BASED ON "STAINING OF THE NUCLEUS IN AT LEAST = 1% OF INVASIVE TUMOR CELLS" PER PRODUCT LABELING. LASTLY, PRODUCT LABELING FOR THE CONFIRM ANTI-ESTROGEN RECEPTOR ER SP1 STATES: "A CONFIRM ANTI-ER (SP1) ANTIBODY NEGATIVE RESULT DOES NOT EXCLUDE THE PRESENCE OF ER. NEGATIVE REACTIONS IN BREAST CARCINOMAS MAY BE DUE TO LOSS OR MARKED DECREASE OF EXPRESSION OF ANTIGEN. THEREFORE, IT IS RECOMMENDED THAT THIS ANTIBODY BE USED IN A PANEL OF ANTIBODIES INCLUDING PROGESTERONE RECEPTOR." THE INVESTIGATION DETERMINED THAT THE DIFFERENCE IN RESULTS IS MOST LIKELY DUE TO VARIATIONS BETWEEN THE DIFFERENT MANUFACTURER'S PRODUCTS, RESULTING IN A SAMPLE-SPECIFIC DETECTION DIFFERENCE. THE INVESTIGATION DID NOT IDENTIFY A PRODUCT PROBLEM.

Description of Event or Problem

THE INITIAL REPORTER ALLEGES THEY RECEIVED A NEGATIVE RESULT FOR A REGIONAL QUALITY CONTROL SAMPLE TESTED WITH CONFIRM ANTI-ESTROGEN RECEPTOR ER SP1 ON A BENCHMARK ULTRA STAINER MODULE. A BREAST CANCER TISSUE SAMPLE USED AS QUALITY CONTROL FOR THE CUSTOMER'S REGION WAS TESTED USING THE CONFIRM ANTI-ESTROGEN RECEPTOR ER SP1 AND THE RESULT WAS NEGATIVE (SLIGHTLY LESS THAN 1%). THE RESULT WAS NOT REPORTED TO THE PATIENT. COMPETITOR PLATFORMS USING OTHER CLONES HAD POSITIVE RESULTS FOR THE SAME CONTROL SAMPLES WITH ESTROGEN RECEPTOR VALUES CLOSE TO 90 %.