Automated mRNA-Based Detection of ER, PR, HER2, and Ki-67 in Breast Cancer Tissue and Cytology Samples in Resource-Limited Settings.

Authors

Partha Basu, Anuradha Talukdar, Poulome Mukherjee, Richard Muwonge, Eric Lucas, Monoj Kumar Deka, Amanjit Bal, Upasana Gautam, Manish Rohilla, Baneet Bansal, Veenu Singla, Siddhant Khare, Andre Lopes Carvalho, Anita Gadgil, Ravi Kannan, Radhika Srinivasan

Published in

Cancer medicine. Volume 15. Issue 10. Pages e72359.

Abstract

Accurate detection of estrogen and progesterone receptors (ER/PR), HER2, and Ki-67 is essential for molecular classification of breast cancer and in deciding upon tailored treatment. In many low- and middle-income countries (LMICs), access to histopathology and immunohistochemistry (IHC) is limited. STRAT4, an automated RT-qPCR assay performed on the widely available GeneXpert platform, offers a potential alternative. We evaluated the performance of STRAT4 on core biopsy, unstained smear of fine-needle aspiration biopsy (FNAB-US), and cellblock samples compared with conventional IHC in 178 histopathology-confirmed breast cancer patients.
Matched core biopsy, cellblock, and FNAB-US samples were analyzed using STRAT4. Concordance with IHC for ER, PR, HER2, and Ki-67 was assessed using percentage agreement and kappa statistics. The effect of alternative dC_t cut-offs used in an earlier study was also examined. Molecular subtype classification derived from STRAT4 was compared with IHC-based classification.
Concordance between STRAT4 and IHC was high for ER across all sample types (κ: 0.78-0.86). PR detection showed substantial agreement for core biopsies (κ = 0.78) and cellblocks (κ = 0.63), but only fair for FNAB-US samples (κ = 0.53). HER2 detection showed moderate agreement (κ = 0.41-0.58), improving with modified cut-offs (κ = 0.57-0.66), especially for FNAB-US. Ki-67 concordance was low (agreement 58.9%-71.0%). Kappa values indicating agreement between molecular subtype classifications using STRAT4 on various samples and routine IHC were as follows: core biopsies = 0.60; cellblocks = 0.61; FNAB-US samples = 0.45.
Detection of ER from FNAB-US, cellblocks, and core biopsies using STRAT4 showed high concordance with IHC. However, the concordance was low to moderate for other markers.

PMID:
42834705
Bibliographic data and abstract were imported from PubMed on 06 Oct 2026.

Read full publication at:
Please sign in to see all details.

Stats

1-terrible, 9-excellent. How would you rate this publication? Sign in in to submit your rating.

Post a comment

You need to be signed in to post comments. You can sign in here.

Comments

There are no comments yet.