Nesković-Konstantinović Z B, Nikolić-Vukosavljević D B, Branković-Magić M V, Mitrovic L B, Spuzić I
Department Medical Oncology, Institute for Oncology and Radiology of Serbia, Belgrad, Yugoslavia.
Neoplasma. 2000;47(2):107-13.
Epidermal growth factor receptor (EGF-R) is known as an indicator of endocrine independence of breast cancer. However, a small proportion of EGF-R expressing tumors was found to respond to endocrine treatments. On the other side, a cut-off point of EGF-R positivity is not yet defined. In the aim to find out whether there exists a cut-off value that sharply discriminate the endocrine sensitive and endocrine insensitive breast cancers, the quantitative EGF-R content was analyzed in a group of 42 female patients with metastatic disease, being routinely treated with chemo-, chemo-endocrine, or endocrine therapy alone. Steroid receptors (SR) and EGF-R were determined by biochemical methods in tissue samples of an unselected group of patients. Patients with metastatic disease, either at diagnosis, or developed after the treatment of operable or locally advanced breast cancer, were included in the present analysis. According to the treatments used, and their therapeutic response, all patients were divided in endocrine sensitive or resistant, and chemo-sensitive or resistant. The SR and EGF-R status and content was analyzed in relation to the sensitivity to both systemic treatments. The EGF-R content was significantly lower in responders to endocrine treatments, compared to non-responders, while there was no difference in EGF-R level, in relation to the sensitivity to chemotherapy. In addition, the EGF-R content was significantly higher in chemo-sensitive tumors, than in endocrine sensitive. On the contrary, ER content was significantly higher in endocrine sensitive, than in endocrine resistant, and in chemo sensitive patients, as well. Similar differences were found in PR content, but they were less pronounced. While the individual ER contents in endocrine sensitive and endocrine resistant tumors overlapped, the EGF-R ranges were different: no one endocrine sensitive tumor exceeded the EGF-R content of 26 fmol/mg, thus suggesting the EGF-R cut-off point of endocrine sensitivity. The clinical use of EGF-R, with the cut-off point of 26 fmol/mg, in addition to clinical criteria of endocrine sensitivity and SRs, would significantly improve the correct endocrine sensitivity prediction (from 52 to 78%). In conclusion, in a group of metastatic breast cancer patients, treated routinely by systemic therapies it was found, that the use of higher cut-off point for EGF-R positivity can improve the prediction of endocrine sensitivity. The prognostic relevance of this cut-off value remains to be analyzed.
表皮生长因子受体（EGF-R）被认为是乳腺癌内分泌独立性的一个指标。然而，发现一小部分表达EGF-R的肿瘤对内分泌治疗有反应。另一方面，EGF-R阳性的临界值尚未确定。为了找出是否存在一个能清晰区分内分泌敏感和内分泌不敏感乳腺癌的临界值，对一组42例患有转移性疾病且正在接受化疗、化疗内分泌联合治疗或单纯内分泌治疗的女性患者的EGF-R定量含量进行了分析。通过生化方法在一组未经挑选的患者的组织样本中测定类固醇受体（SR）和EGF-R。本分析纳入了在诊断时患有转移性疾病或在可手术或局部晚期乳腺癌治疗后出现转移性疾病的患者。根据所使用的治疗方法及其治疗反应，将所有患者分为内分泌敏感或耐药、化疗敏感或耐药。分析了SR和EGF-R的状态及含量与两种全身治疗敏感性的关系。与无反应者相比，内分泌治疗反应者的EGF-R含量显著更低，而EGF-R水平与化疗敏感性无关。此外，化疗敏感肿瘤中的EGF-R含量显著高于内分泌敏感肿瘤。相反，内分泌敏感患者的雌激素受体（ER）含量显著高于内分泌耐药患者以及化疗敏感患者。孕激素受体（PR）含量也发现了类似差异，但不太明显。虽然内分泌敏感和内分泌耐药肿瘤中的个体ER含量有重叠，但EGF-R范围不同：没有一个内分泌敏感肿瘤超过26 fmol/mg的EGF-R含量，因此提示了内分泌敏感性的EGF-R临界值。除了内分泌敏感性和SRs的临床标准外，使用26 fmol/mg临界值的EGF-R进行临床应用，将显著提高正确的内分泌敏感性预测（从52%提高到78%）。总之，在一组接受全身治疗的转移性乳腺癌患者中发现，使用更高的EGF-R阳性临界值可以改善内分泌敏感性的预测。这个临界值的预后相关性仍有待分析。
