TY - JOUR
T1 - Multicenter Harmonization Study of Pan-Trk Immunohistochemistry for the Detection of NTRK3 Fusions
AU - Adam, Julien
AU - Stang, Nolwenn Le
AU - Uguen, Arnaud
AU - Badoual, Cécile
AU - Chenard, Marie Pierre
AU - Lantuéjoul, Sylvie
AU - Maran-Gonzalez, Aurélie
AU - Robin, Yves Marie
AU - Rochaix, Philippe
AU - Sabourin, Jean Christophe
AU - Soubeyran, Isabelle
AU - Sturm, Nathalie
AU - Svrcek, Magali
AU - Vincent-Salomon, Anne
AU - Radosevic-Robin, Nina
AU - Penault-Llorca, Frédérique
N1 - Publisher Copyright:
© 2023 United States & Canadian Academy of Pathology
PY - 2023/8/1
Y1 - 2023/8/1
N2 - Pan-Trk immunohistochemistry has been described as a screening test for the detection of NTRK fusions in a broad spectrum of tumor types. However, pan-Trk testing in the clinical setting may be limited by many factors, including analytical parameters such as clones, platforms, and protocols used. This study aimed to harmonize pan-Trk testing using various clones and immunohistochemical (IHC) platforms and to evaluate the level of analytical variability across pathology laboratories. We developed several IHC pan-Trk assays using clones EPR17341 (Abcam) and A7H6R (Cell Signaling Technology) on Ventana/Roche, Agilent, and Leica platforms. To compare them, we sent unstained sections of a tissue microarray containing 9 cases with NTRK3 fusions to participating laboratories, to perform staining on Ventana/Roche (10 centers), Agilent (4 centers), and Leica (3 centers) platforms. A ready-to-use pan-Trk IVD assay (Ventana/Roche) was also performed in 3 centers. All slides were centrally and blindly reviewed for the percentage of stained tumor cells. Laboratory-developed tests with clone EPR17341 were able to detect pan-Trk protein expression in all cases, whereas lower rates of positivity were observed with clone A7H6R. Moderate to strong variability of the positive cases rate was observed with both antibodies in each IHC platforms type and each of the positivity cut points evaluated (≥1%, ≥10%, and ≥50% of stained tumor cells). The rate of false-negative cases was lower when pan-Trk staining was assessed with the lowest positivity threshold (≥1%). In conclusion, most evaluated pan-Trk IHC laboratory-developed tests were able to detect NTRK3-fusion proteins; however, a significant analytical variability was observed between antibodies, platforms, and centers.
AB - Pan-Trk immunohistochemistry has been described as a screening test for the detection of NTRK fusions in a broad spectrum of tumor types. However, pan-Trk testing in the clinical setting may be limited by many factors, including analytical parameters such as clones, platforms, and protocols used. This study aimed to harmonize pan-Trk testing using various clones and immunohistochemical (IHC) platforms and to evaluate the level of analytical variability across pathology laboratories. We developed several IHC pan-Trk assays using clones EPR17341 (Abcam) and A7H6R (Cell Signaling Technology) on Ventana/Roche, Agilent, and Leica platforms. To compare them, we sent unstained sections of a tissue microarray containing 9 cases with NTRK3 fusions to participating laboratories, to perform staining on Ventana/Roche (10 centers), Agilent (4 centers), and Leica (3 centers) platforms. A ready-to-use pan-Trk IVD assay (Ventana/Roche) was also performed in 3 centers. All slides were centrally and blindly reviewed for the percentage of stained tumor cells. Laboratory-developed tests with clone EPR17341 were able to detect pan-Trk protein expression in all cases, whereas lower rates of positivity were observed with clone A7H6R. Moderate to strong variability of the positive cases rate was observed with both antibodies in each IHC platforms type and each of the positivity cut points evaluated (≥1%, ≥10%, and ≥50% of stained tumor cells). The rate of false-negative cases was lower when pan-Trk staining was assessed with the lowest positivity threshold (≥1%). In conclusion, most evaluated pan-Trk IHC laboratory-developed tests were able to detect NTRK3-fusion proteins; however, a significant analytical variability was observed between antibodies, platforms, and centers.
KW - cancer biomarkers
KW - immunohistochemistry
KW - oncogenic fusions
UR - http://www.scopus.com/inward/record.url?scp=85168315914&partnerID=8YFLogxK
U2 - 10.1016/j.modpat.2023.100192
DO - 10.1016/j.modpat.2023.100192
M3 - Article
C2 - 37084942
AN - SCOPUS:85168315914
SN - 0893-3952
VL - 36
JO - Modern Pathology
JF - Modern Pathology
IS - 8
M1 - 100192
ER -