Marker assessments inER‐positive breast cancers: old markers, new applications?

Abstract

Evaluation of oestrogen receptor (ER) expression by immunostaining is essential in the pathological assessment of breast cancer. Its expression is intercorrelated with clinicopathological features, molecular typing, and treatment selection. The development of novel therapeutic agents related to ER status, the recent ASCO introduction of an ER-low positive category of breast cancers, and the ever-increasing plethora of diagnostic and theragnostic markers call for a timely update. In this article we aim to review the clinicopathological features of ER-positive breast cancers, with an emphasis on ER-low positive breast cancers, and a focus on updating the (i) assessment, reporting and interpretation of ER immunohistochemical (IHC) staining, (ii) correlations of ER status with other diagnostic and theragnostic markers, and (iii) implications for treatment selection and response. In the face of the developments in IHC and molecular techniques and targeted therapy, ER immunostaining is still expected to remain as the core component of prognostic and theragnostic assessment of breast cancers.

Immunocytochemical markers, molecular testing and digital cytopathology for aspiration cytology of metastatic breast carcinoma

“…Examples are GATA3, GCDFP15, mammaglobin, TRPS1 and SOX10. 15,[27][28][29] GATA3, GCDFP15 and mammaglobin are preferentially expressed in hormone-positive breast cancers, whereas SOX10 is considered as a marker for hormone-negative breast cancers 15,28 (Figure 1). These markers have been validated in cytologic specimens of metastatic breast carcinomas.…”

“…A large number of markers are available for confirmation of breast primary. Examples are GATA3, GCDFP15, mammaglobin, TRPS1 and SOX10 15,27–29 . GATA3, GCDFP15 and mammaglobin are preferentially expressed in hormone‐positive breast cancers, whereas SOX10 is considered as a marker for hormone‐negative breast cancers 15,28 (Figure 1).…”

TRPS1 is a promising marker for all subtypes of breast cancer

“…21 As well as its mechanistic roles in breast cancers, the diagnostic value of TRPS1 has been explored recently. [23][24][25][26][27][28] It has been demonstrated to be a potentially useful breast marker, with high expression rates in all breast cancer subtypes but absent to low expression in other solid tumours, such as carcinomas arising from pancreas, lung, gastrointestinal tract, liver and urothelium. 23,24 Its expression rates were similar to GATA3 in ER-positive and HER2-positive breast cancers, 24,25 while it maintained a remarkably high expression in TNBC of more than 80%.…”

“…It is also a critical regulator of M phase progression 21 . As well as its mechanistic roles in breast cancers, the diagnostic value of TRPS1 has been explored recently 23–28 . It has been demonstrated to be a potentially useful breast marker, with high expression rates in all breast cancer subtypes but absent to low expression in other solid tumours, such as carcinomas arising from pancreas, lung, gastrointestinal tract, liver and urothelium 23,24 .…”

Molecular subtypes of colorectal cancer in the era of precision oncotherapy: Current inspirations and future challenges

“…5 In addition, CRC cases with similar clinical presentations have significant differences in treatment response and survival rate. 6 For decades, molecular typing analysis of solid tumors, represented by omics exploration has developed rapidly and has been widely carried out in lung cancer, 7 breast cancer, 8 gastric cancer, 9 pancreatic ductal adenocarcinoma, 10 endometrial cancer, 11 and so on. CRCrelated molecular typing has also been reported for early diagnosis, treatment, and prognosis assessment of tumors.…”