NY-ESO-1 expression in DCIS: A new predictor of good prognosis

BACKGROUND At present, it is difficult to predict which patients with ductal carcinoma-in-situ (DCIS) will subsequently develop frank invasive breast cancer (IDC). A recent survey by our group has shown that NY-ESO-1 and MAGEA are both expressed in DCIS. This study was aimed at determining whether expression of these antigens was related to the later development of IDC. RESULTS 14 of 42 (33%) of patients developed invasive breast cancer during the follow up period. Only one of those DCIS cases that relapsed was positive for NYESO-1 at diagnosis. In contrast, DCIS samples of 15 of the 28 (54%) of those patients who remained disease-free expressed NY-ESO-1. (Permutation chi square p=0.0033). METHODS We identified 42 patients with DCIS, and followed them up for more than 10 years. NY-ESO-1 and MAGEA were demonstrated by immunostaining as were CD8+ infiltrates on all sections together with the conventional markers, ER, PR, and HER2. CONCLUSIONS Expression of NY-ESO-1 may predict those patients who will not subsequently develop invasive breast cancer and could therefore potentially be helpful in defining prognosis in patients with DCIS.