EXPRESSION OF TENASCIN-C IN INTRADUCTAL CARCINOMA OF HUMAN BREAST - RELATIONSHIP TO INVASION

Tenascin-C (Tn-C) is an extracellular matrix glycoprotein that appears in areas of epithelial-mesenchymal interaction during fetal developme nt and in neoplasia. The immunohistochemical expression of Tn-C and it s relationship to histology, nuclear grade, microinvasion, oestrogen ( ER) and progesterone receptors (PR), and to cell proliferation measure d by Ki-67 expression were studied in 89 intraductal breast carcinomas (DCIS). Periductal Tn-C was noted in 87% and stromal Tn-C in 25% of t he tumours. Stromal expression was associated with moderate to strong periductal expression and microinvasion. Periductal expression was ass ociated with comedo-type, nuclear grade, microinvasion, Ki-67 expressi on, and lack of PR. The distribution of Tn-C was compared in DCIS and in the intraductal component from another series of small axillary nod e-negative invasive breast carcinomas (n = 44). Tn-C was present in th e stroma of pure DCIS in 25% and in the intraductal component of the o ther series in 82%. Thus, stromal or moderate to strong periductal Tn- C expression in DCIS may relate to early invasion. DCIS with weak peri ductal or missing Tn-C expression may be a subgroup with benign behavi our. (C) 1998 Elsevier Science Ltd. All rights reserved.