ADVIA CENTAUR CA 15-3

Additional Manufacturer Narrative

A UNITED STATES (US) CUSTOMER REPORTED OBSERVATION OF A DEPRESSED ADVIA CENTAUR CANCER ANTIGEN 15-3 (CA 15-3) RESULT WHICH WAS DISCORDANT RELATIVE TO REPEAT TESTING. THE QUALITY CONTROL (QC) RESULTS RECOVERED WITHIN THE LABORATORY ESTABLISHED RANGES ON THE DAY OF THE EVENT. THE ASSAY'S INSTRUCTIONS FOR USE (IFU) STATES THE FOLLOWING UNDER INTERPRETATION OF RESULTS: "RESULTS OF THIS ASSAY SHOULD ALWAYS BE INTERPRETED IN CONJUNCTION WITH PATIENT'S MEDICAL HISTORY, CLINICAL PRESENTATION AND OTHER FINDINGS." SIEMENS IS EVALUATING THE EVENT.

Description of Event or Problem

THE CUSTOMER REPORTED OBSERVATION OF A DEPRESSED ADVIA CENTAUR CANCER ANTIGEN 15-3 (CA 15-3) RESULT WHICH WAS DISCORDANT RELATIVE TO REPEAT TESTING WHEN USING LOT# 221. AN INITIAL DEPRESSED RESULT WAS OBTAINED FOR THE PATIENT SAMPLE IN QUESTION. THE DEPRESSED RESULT WAS REPORTED TO THE PHYSICIAN(S), WHO DID NOT QUESTION THE RESULT. THE SAME SAMPLE WAS RETESTED ON THE ORIGINAL ANALYZER WHICH OBTAINED A HIGHER RESULT. THEN, THE SAMPLE WAS REPEATED ON AN ALTERNATE ANALYZER WHICH PRODUCED A SIMILAR HIGHER RESULT. THE HIGHER RESULTS WERE CONSIDERED CORRECT, AND THE RESULT OBTAINED ON THE ORIGINAL ANALYZER WAS REPORTED TO THE PHYSICIAN(S). IT IS UNKNOWN IF THERE WAS AN EXISTING CANCER DIAGNOSIS WITH THE AFFECTED PATIENT, BUT THE CUSTOMER CONFIRMED THAT THE PATIENT WAS TESTED FOR ONCOLOGY. THERE ARE NO KNOWN REPORTS OF PATIENT INTERVENTION OR ADVERSE HEALTH CONSEQUENCES DUE TO THIS EVENT.

Additional Manufacturer Narrative

AN INITIAL MDR 1219913-2025-00184 WAS FILED ON 15-OCT-2025. ADDITIONAL INFORMATION (06-NOV-2025): SIEMENS CONCLUDED INVESTIGATION FOR A UNITED STATES (US) CUSTOMER REGARDING OBSERVATION OF A DEPRESSED ADVIA CENTAUR CANCER ANTIGEN 15-3 (CA 15-3) RESULT WHICH WAS DISCORDANT RELATIVE TO REPEAT TESTING. THE CUSTOMER OBSERVED THAT THE SIDES OF THE REAGENT PACK WERE BANDED WITH SOLID PHASE PARTICLES WHEN THE ORIGINAL REAGENT PACK WAS REMOVED. SIEMENS REVIEWED THE INSTRUMENT DATA AND THE INFORMATION PROVIDED BY THE CUSTOMER. REAGENT ISSUES WERE RULED OUT BASED ON REVIEW OF QUALITY CONTROLS (QC) WHICH SHOWED RECOVERY WITHIN ACCEPTABLE RANGES WITH APPROPRIATE PARTICLE RESUSPENSION FROM READY PACK SIDEWALL. NO ISSUES WERE REPORTED WITH OTHER PATIENT SAMPLES. THE PERCENT BIAS NOTED IN BOTH PATIENT AND QC RESULTS SHOWED CONSISTENT RECOVERY. SIEMENS INFORMED THE CUSTOMER THAT OCCASIONAL LIGHT SOLID-PHASE BANDING OR RINGS MAY APPEAR ON THE READY PACK SIDEWALLS OR LID, AND IF OBSERVED, THE PARTICLES SHOULD BE GENTLY RESUSPENDED BY CAREFULLY REMOVING AND HAND-MIXING THE READY PACK WITHOUT ALLOWING REAGENT LEAKAGE FROM THE PIERCED FILM. A PRODUCT PROBLEM HAS NOT BEEN IDENTIFIED. RETURN OF THE PATIENT SAMPLE FOR FURTHER INVESTIGATION WAS NOT WARRANTED AS THE CUSTOMER HAD CONDUCTED APPROPRIATE TESTING. BASED ON THE AVAILABLE INFORMATION, THE PROBABLE CAUSE OF THE DISCORDANT RESULT WAS DUE TO THE SOLID PHASE BANDING WITH THE REAGENT PACK. THE CUSTOMER IS OPERATIONAL, AND THE REPORTED ISSUE WAS RESOLVED BY ROUTINE TROUBLESHOOTING. NOTE: IN SECTION H6, CODES FOR INVESTIGATION FINDINGS AND INVESTIGATION CONCLUSIONS WERE UPDATED.