Is oestrogen receptor-negative/progesterone receptor-positive (ER−/PR+) a real pathological entity?

24 Aug 2021
Adedayo A Onitilo, Jessica Engel, Adedayo O Joseph, Ya-Huei Li

Background: The existence of oestrogen receptor-negative (ER−)/progesterone receptor-positive (PR+) breast cancer continues to be an area of controversy amongst oncologists and pathologists.

Methods: To re-evaluate breast cancers originally classified as ER−/PR+ via Oncotype DX® assay and compare molecular phenotype with Recurrence Score® (RS) result, clinicopathologic features and clinical outcomes were retrospectively obtained from electronic health records between January 1998 and June 2005. Archived formalin-fixed, paraffin-embedded (FFPE) tumour specimens were tested for the expression of ER, PR and human-epidermal-growth-factor-2. The number of positive ER−/PR+ samples confirmed by transcriptional analysis was the primary outcome of interest with event-free and overall survival as secondary outcomes. Biopsies from 26 patients underwent Oncotype DX testing and analysis.

Results: Approximately 60% were middle-aged (40–50 years old) women, and 84.6% had invasive ductal carcinoma. Based on the Oncotype DX assay, approximately 65% (N = 17) had ER+/PR+ status; 23% (N = 6) had ER−/PR− status; and 12% had a single hormone positive receptor (1 ER–/PR+, 2 ER+/PR–) status. Almost one-quarter of patients were stratified into the low-RS (<18) or intermediate-RS (18–30) results, and half of the patients had a high-RS (>30) result.

Conclusion: Our findings suggest the ER−/PR+ subtype is not a reproducible entity and emphasises the value of retesting this subtype via molecular methods for appropriate treatment selection and patient outcomes. Multigene assay analysis may serve as a second-line or confirming tool for clinical determination of ER/PR phenotype in breast cancer patients for targeted therapies.

Related Articles

Don Thiwanka Wijeratne, Christopher M Booth, Sanjeewa Seneviratne, Bishal Gyawali, Matt Jalink, Malinthi Soysa, Sachith Abhayaratna, Hasitha Promod, Punika Wijesinghe, Sanjeeva Gunasekera
Renata Colombo Bonadio, Ana Paula Messias, Otavio Augusto Moreira, Letícia Vecchi Leis, Bruna Zanin Orsi, Laura Testa, Maria del Pilar Estevez-Diz
Bolanle C Adegboyega, Adewumi O Alabi, Adedayo O Joseph, Nwamaka Lasebikan, Luther A Agaga, Kehinde O Ololade, Anthonia C Sowunmi
Shridevi Subramaniam, Yek-Ching Kong, Hafizah Zaharah, Cuno SPM Uiterwaal, Andrea Richard, Nur Aishah Taib, Azura Deniel, Kok-Han Chee, Ros Suzanna Bustamam, Mee-Hoong See, Alan Fong, Cheng-Har Yip, Nirmala Bhoo-Pathy
Marianne Gnanamuttupulle, Oliver Henke, Shilanaiman Hilary Ntundu, Furaha Serventi, Leila E Mwakipunda, Patrick Amsi, Alex Mremi, Kondo Chilonga, David Msuya, Samuel G Chugulu