@article{aa6c44f5dfce46a697d5c9cb1f669b93,
title = "Effect of preanalytic variables on an automated PTEN immunohistochemistry assay for prostate cancer",
abstract = "Context.-Phosphatase and tensin homolog (PTEN) is a promising prognostic and potentially predictive biomarker in prostate cancer. Objective.-To assess the effects of preanalytic variables on an analytically validated and fully automated PTEN immunohistochemistry assay. Design.-PTEN immunohistochemistry was performed on Ventana immunostaining systems. In benign prostate tissues, immunostaining intensity across variable conditions was assessed by digital image analysis. In prostate tumor tissues, immunostaining was scored visually. Results.-Delay of fixation for 4 hours or longer at room temperature or 48 hours or longer at 4°C and duration of formalin fixation did not significantly alter immunostaining intensity. Intensity of staining was highest in 10% formalin compared with other fixatives. Tumor tissues with PTEN loss processed using protocols from 11 academic institutions were all evaluable and scored identically. PTEN immunostaining of needle biopsies where tissue blocks had been stored for less than 10 years was more frequently scored as nonevaluable compared with blocks that had been stored for 10 years or longer. This effect was less evident for radical prostatectomy specimens, where low rates of nonevaluable staining were seen for 23 years or more of storage. Storage of unstained slides for 5 years at room temperature prior to immunostaining resulted in equivalent scoring compared with freshly cut slides. Machine-to-machine variability assessed across 3 Ventana platforms and 2 institutions was negligible in 12 tumors, and platform-to-platform variability was also minor comparing Ventana and Leica instruments across 77 tumors (k = 0.926). Conclusions.-Automated PTEN immunostaining is robust to most preanalytic variables in the prostate and may be performed on prostate tumor tissues subjected to a wide range of preanalytic conditions. These data may help guide assay development if PTEN becomes a key predictive biomarker.",
author = "Guedes, {Liana B.} and Morais, {Carlos L.} and Helen Fedor and Jessica Hicks and Bora Gurel and Jonathan Melamed and Peng Lee and Anuradha Gopalan and Knudsen, {Beatrice S.} and True, {Lawrence D.} and Scher, {Howard I.} and Fine, {Samson W.} and Trock, {Bruce J.} and {De Marzo}, {Angelo M.} and Lotan, {Tamara L.}",
note = "Funding Information: Funding for this research was provided in part by a Transformative Impact Award from the CDMRP (W81XWH-13-2-0070) and NCI Cancer Center support grant P30 CA006973. Additional funding was provided by the NIH/NCI Prostate SPORE Pathology Cores P50CA58236 and P50CA097186; Defense Prostate Cancer Research Program awards W81XWH-14-2-0182, W81XWH-14-2-0183, and W81XWH-14-2-0185; the Prostate Cancer Biorepository Network (PCBN); NIH/NCI Prostate SPORE grant P50-CA92629; NIH/NCI Cancer Center support grant P30 CA008748; and the Prostate Cancer Foundation. H.I.S. was additionally supported by NIH/NCI Prostate SPORE grant P50-CA92629, NIH/NCI Cancer Center support grant P30 CA008748, and the Prostate Cancer Foundation. The Inter-SPORE Prostate Biomarkers Study Team was a multi-institutional effort involving investigators from 11 different academic institutions, including Jonathan Said, MD (UCLA); Patricia Troncoso, MD (MD Anderson Cancer Center); Victor Reuter, MD, and Samson Fine, MD (Memorial Sloan Kettering Cancer Center); Jeffrey Simko, MD (University of California, San Francisco); Mark Rubin, MD (Dana Farber Cancer Institute); Rajal Shah, MD (University of Michigan); Michael Pins, MD (Northwestern University); Gustavo Ayala, MD (Baylor University); Robert Jenkins, MD, PhD, and John Cheville, MD (Mayo Clinic); Bruce Trock, PhD, and Angelo De Marzo, MD, PhD (Johns Hopkins University); and Beatrice Knudsen, MD, PhD, and Lawrence True, MD (University of Washington). Funding Information: Drs Lotan and De Marzo have received research support from Ventana to support other projects. Drs Trock and De Marzo have received research support from and consulted for Myriad Genetics. Dr Trock has also consulted for GenomeDx Biosciences and received a research grant from MDxHealth. Dr De Marzo served as a consultant for Cepheid Inc, is on the advisory board for Myriad Genetics, and has sponsored research from Jansson R&D and Myriad. The other authors have no relevant financial interest in the products or companies described in this article. Publisher Copyright: {\textcopyright} 2019 College of American Pathologists. All rights reserved.",
year = "2019",
month = mar,
doi = "10.5858/arpa.2018-0068-OA",
language = "English (US)",
volume = "143",
pages = "338--348",
journal = "Archives of Pathology and Laboratory Medicine",
issn = "0003-9985",
publisher = "College of American Pathologists",
number = "3",
}