Manufacturer evaluation of the information available, which includes the relevant run events and service events, indicates that the two (2) slides for which false positive staining was reported (hereafter referred to as the "affected slides") were: slide id: (b)(6) with case id: (b)(4), which was stained at slide (b)(4) on slide staining assembly (ssa) 1 in run 20651 executed on (b)(6) 2021, and slide id: (b)(6) with case id: (b)(4), which was stained at slide position 3 on ssa 1 in run 21164 executed on (b)(6) 2021.Staining of both affected slides was performed using bond-iii automated stainer serial number (b)(4); and both run 20651 and 21164 completed successfully with no recorded event(s) to suggest any malfunction(s) of the instrument.Additionally, slide id: (b)(6) was stained in run 20651 together with two (2) other slides with bond slide ids (b)(6) using the same staining protocol and the same reagents with no problem regarding the quality of staining reported to the manufacturer for slides with slide ids: (b)(6); and slide id: (b)(6)was stained in run 21164 together with three (3) other slides with bond slide ids: (b)(6) using the same staining protocol and the same reagents, with no problem regarding the quality of staining reported to the manufacturer for slides with slide ids: (b)(6).The information available also indicates that staining of both of the affected slides was performed using on-the-instrument factory default *dewax protocol, with factory default heat induced epitope retrieval (her) protocol *her 40 min and er1/ and custom staining protocol "her2 (b)(6)" with leica biosystems bond ready to use primary antibody *c-erbb-2 oncoprotein (clone cb11) catalog no: pa0571 and the bond polymer refine detection kit.The class i, bond ready-to-use primary antibody c-erbb-2 oncoprotein (cb11) instructions for use contain the following information: "the clinical interpretation of any staining or its absence should be complemented by morphological studies and proper controls and should be evaluated within the context of the patient's clinical history and other diagnostic tests by a qualified pathologist," and "c-erbb-2 oncoprotein (cb11) primary antibody was developed for use on the automated bond system (includes leica bondmax system and leica bond-iii system) in combination with bond polymer refine detection.The recommended staining protocol for c-erbb-2 oncoprotein (cb11) primary antibody is ihc protocol f.Heat induced epitope retrieval is recommended.Using bond epitope retrieval solution 2 for 20 minutes." the facts indicate that the bond ready-to-use primary antibody c-erbb-2 oncoprotein (cb11) was not used in accordance with the manufacturer recommendations detailed in the instructions for use (ifu), because the available information indicates that the affected slides were stained using bond epitope retrieval solution 1 for 40 minutes rather than the recommended bond epitope retrieval solution 2 for 20 minutes; and the custom "her2 (b)(6)" protocol used for staining of the affected slides is not identical to the recommended ihc protocol f.Leica biosystems newcastle cannot assess the impact this may or may not have had on the quality of staining of the affected slides.The information available suggests that run 20651 and run 21164 had both positive and negative tissue controls run.However, information available does not indicate the type of control tissue used and whether they were placed on the same slides as the tissue for case id: (b)(4), in line with the instrument manufacturer recommendations 6.2 of the leica biosystems bond system user manual for bond systems running bond 6.0 software (for use only in the usa) entitled "working with controls," the run events for run 20651 and run 21164 do not suggest that slides with control tissue were placed on the same ssa as bond slide id: (b)(6) with case id: (b)(4) and bond slide id: (b)(6) for case id: (b)(4).Manufacturer evaluation of the information available did not identify any instrument-or reagent related root cause for the reported false positive staining of bond slide id: (b)(6) with case id: (b)(4) and bond slide id: (b)(6) for case id: (b)(4), following processing using bond-iii automated stainer serial number (b)(4).The root cause of the false positive staining reported by the complainant on 30 (b)(6) 2021 could not be determined from the information available.
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