Jornal de Citologia e Histologia

P53 Overexpression in Ductal Carcinoma in situ of the Breast

Abstract

Kikuchi S, Osako T, Nishiyama Y, Nakano M, Tashima R, Fujisue M, Toyozumi Y, Arima N and Reiki Nishimura

Background: Ductal carcinoma in situ (DCIS) is the most common type of non-invasive breast cancer. DCIS is not life threatening but can increase the risk of invasive ductal carcinoma (IDC) development. However, the role of P53 expression in the progression to invasiveness in DCIS is unclear. In this retrospective study, the differences in biological markers, including protein 53 (P53) expression, between DCIS and IDC ≤5 mm in diameter (T1a) were evaluated.
Methods: Among 2,497 primary breast cancer patients, who underwent initial surgery between 2001 and 2010, 267 (10.4%) patients were diagnosed with DCIS and 86 (3.4%) patients were diagnosed with T1a. P53 expression was evaluated using immunohistochemical analysis, and the distribution (<10%, <50%, and ≥50%) and the association with other biological markers was investigated in DCIS and T1a.
Results: Overexpression (≥ 50%) of P53 was seen in 13% of patients with DCIS and in 24% of patients with T1a, constituting a significant difference (p=0.001). P53 overexpression was significantly associated with higher nuclear grade, lower rates of estrogen receptor (ER)/progesterone receptor (PgR) positivity, higher rates of epidermal growth factor receptor 2 (HER2) positivity, and higher values of nuclear protein Ki-67 in patients with DCIS. Recurrence rates did not differ significantly between DCIS and T1a. Logistic regression analysis of factors associated with invasiveness revealed that P53 overexpression was one of the significant factors, and ER negativity was found to be a significant independent factor in multivariate analysis.
Conclusion: P53 overexpression reflected the aggressiveness and correlated with the invasiveness in DCIS. These findings suggest that P53 may play an important role in invasion of DCIS in the breast.