Expression of Cyclin D1 in Invasive Lobular Carcinoma of the Breast and Its Significance

  Objective  To investigate the expression and its significance of Cyclin D1 in invasive lobular carcinoma (ILC) of the breast.

  Methods  The specimens from 75 cases of ILC were detected using immunohistochemical method.

  Results  Of these 75 cases, Cyclin D1 was positive on the nucleus in 70 cases (93.33%), among which 41 (54.67%) showed strong diffuse staining (3 +, 6-7 points), and 21 (28%) were moderately positive (2 +, 4-5 points), and 8 (10.67%) were weak positive (1 +, 2-3 points). Only 5 (6.67%) cases showed negative results (0-1 points). The positive expression of Cyclin D1 showed no significant differences among patients in terms of age (> 50 years), maximum tumor diameter (> 2cm), lymph node metastasis, involvement of papillary interstitial tissue and the large duct beneath it, existence of estrogen and progesterone receptors, and the possible mutation of P53. However, an inverse correlation was found between the degrees of the positive staining of Cyclin D1 and the lymph node metastasis (P < 0.05).

  Conclusion  Cyclin D1 is overexpressed in ILC, suggesting that there may be certain genetic abnormalities.