Chromogranin A and chromogranin B in noninvasive and invasive breast carcinoma

Recent progress in the study of chromogranins has revealed that there are many novel peptides derived from chromogranin with their multiple pathophysiologic roles. To learn the possible roles of chromogranin in breast carcinoma, we immunohistochemically investigated tissue localization of chromogranin A (CgA) and chromogranin B (CgB) in 10 normal breast tissues, 23 noninvasive ductal carcinomas (NIDCs), and 169 invasive ductal carcinomas (IDCs) and compared their expression with estrogen receptor (ER), progesterone receptor (PR), and Ki67. CgA and CgB were sporadically detected in normal cells of the ducts, acini, and luminal secretion. The expression of CgA and CgB was higher in NIDCs than in IDCs: CgA = 70% of NIDC vs 22% of IDC and CgB = 65% of NIDC vs 30% of IDC. There was a statistical correlation between the expression of CgA and PR (p < 0.05) and CgB and ER (p < 0.05) in IDCs without lymph node metastasis. On the other hand, there was a significant correlation between expression of CgB and PR and an inverse correlation between CgA and Ki67 in IDCs of overall cases. The data suggest that CgA and CgB may play some role in the early phase of neoplastic progression.