Supplementary file 1_Application of TRPS1 in ER-negative or low expression distant metastatic breast carcinoma.docx

PurposeTraditional markers have various limitations in recognizing the breast origin of distant metastatic breast carcinoma (DMBC), especially in ER-negative or low expression cases. In recent years, TRPS1 has been reported as a breast marker with satisfactory sensitivity and specificity in triple-negative breast cancers (TNBC). We aimed to compare the expression of TRPS1, GATA3, and GCDFP-15 in ER-negative or low-ER-expressing DMBC, and to further evaluate the diagnostic value of TRPS1.
MethodsImmunohistochemical staining for TRPS1, GATA3, and GCDFP-15 was performed in 107 cases of ER-negative or low expression DMBC specimens. Nuclear staining was considered positive for TRPS1 and GATA3, and cytoplasmic staining was considered positive for GCDFP-15.
ResultsThe positive rates for TRPS1, GATA3, and GCDFP-15 were 90.65% (97/107), 91.59% (98/107), and 42.99% (46/107), respectively. There was no significant difference in the expression rate and intensity between the first two markers (p = 0.929), but both rates were significantly higher than that of GCDFP-15 (p < 0.05). Among these, 6 cases showed positive expression for TRPS1 while GATA3 and GCDFP-15 were negative; 8 cases showed positive expression for GATA3 while TRPS1 and GCDFP-15 were negative.
ConclusionTRPS1 is as effective as GATA3 in confirming breast origin for ER-negative or low expression DMBC, and the two markers exhibit excellent complementary effects, both outperforming GCDFP-15. The combined application of TRPS1 and GATA3 is the optimal method to confirm that ER-negative or low-expression distant metastatic carcinoma originates from the breast.

目的：传统标志物在识别远处转移性乳腺癌（distant metastatic breast carcinoma, DMBC）的乳腺起源时存在诸多局限，尤其在雌激素受体（Estrogen Receptor, ER）阴性或低表达病例中。近年来，TRPS1被报道为一种在三阴性乳腺癌（triple-negative breast cancers, TNBC）中兼具良好灵敏度与特异度的乳腺标志物。本研究旨在对比TRPS1、GATA3及GCDFP-15在ER阴性或低ER表达的DMBC中的表达情况，并进一步评估TRPS1的诊断价值。
方法：对107例ER阴性或低ER表达的DMBC标本进行TRPS1、GATA3及GCDFP-15的免疫组化染色。其中，TRPS1与GATA3以细胞核染色为阳性判定标准，GCDFP-15以细胞质染色为阳性判定标准。
结果：TRPS1、GATA3及GCDFP-15的阳性率分别为90.65%（97/107）、91.59%（98/107）及42.99%（46/107）。前两种标志物的表达率与表达强度均无显著差异（p = 0.929），但二者的阳性率均显著高于GCDFP-15（p < 0.05）。其中，6例患者的TRPS1呈阳性表达，而GATA3与GCDFP-15均为阴性；8例患者的GATA3呈阳性表达，而TRPS1与GCDFP-15均为阴性。
结论：TRPS1在确认ER阴性或低表达DMBC的乳腺起源方面效果与GATA3相当，二者具备优异的互补效应，且二者的诊断效能均优于GCDFP-15。联合应用TRPS1与GATA3是确认ER阴性或低表达远处转移性癌为乳腺来源的最优方案。