Immunohistochemical Re-Evaluation of Toker Cells in the Epidermis of the Nipple
Michio Shimizu, Masaru Nakamura, Hiroshi Yamaguchi, Koji Nagata, Masanori Yasuda. Saitama Medical University International Medical Center, Hidaka, Saitama, Japan
Background: Toker cells have been attracting attention as a precursor for Paget's disease. In 1970 Cyril Toker described clear cells of the nipple epidermis, and these clear cells are now recognized as Toker cells. Immunohistochemically, Toker cells are positive for cytokeratin 7 (CK7), but their reactivity for estrogen receptor (ER), progesterone receptor (PR), and HER2 is still controversial. Here we reevaluated CK7-positive cells in the epidermis of the nipple using other immuhohistochemical markers.
Design: Nipple tissue was obtained from 40 cases of mastectomy specimens for breast cancer. Serial sections of the formalin-fixed paraffin blocks were made from the nipple. None of the nipple tissues had any breast cancer lesions, and all were histologically unremarkable. Immunohistochemical staining for CK7, ER, PR, HER2, GCDFP-15, androgen receptor (AR) were performed on these sections, in addition to hematoxylin-eosin (HE) stain.
Results: CK7-positive cells in the epidermis were observed in 14 out of the 40 cases (35%), and the number of these cells per section ranged from 3 to 70. These positive cells were sparsely distributed, and small nests consisting of several such cells were also found. In addition, these cells were usually located at the basal part of the epidermis. In these 14 CK7-positive cases, 8 cases were positive for GCDFP-15, 6 cases positive for ER, and 1 case positive for GCDFP-15. PR was negative in all 14 cases.
Conclusions: Although CK-7-positive cells were found in 35% of mastectomy specimens, the incidence of real Toker cells in the epidermis of the nipple may be lower. By the use of strict criteria (CK7 positive, and ER, PR, HER2 and GCDFP-15 negative) the real Toker cells could be observed in 15% of mastectomy specimens.
Wednesday, March 6, 2013 9:30 AM
Poster Session V # 71, Wednesday Morning