Pleomorphic Calcifications, Tumor Markers, and Response to Therapy

IntroductionMany breast cancers are initially identified by pleomorphic calcifications (PC) on mammography (MG). We hypothesized that presence of PC correlates with primary tumor markers and with response to systemic therapy.MethodsMammograms of women with Stage I-III breast cancer were evaluated for the presence of PC. Only patients with biopsy proven invasive carcinoma in association with PC were included. Primary tumor markers (ER, PgR, and HER2) were determined in the standard manner at the time of core biopsy and correlated with presence or absence of PC on MG. We also evaluated cyclooxygenase-2 (COX2), based on data showing a role in tumor progression and possible interaction with HER2 and/or ER. Primary tumors were immunostained with an anti-COX2 monoclonal antibody, and staining of ≥ 5% or more of tumor cells was considered as positive. For response to therapy analyses, complete pathologic response (pCR) was defined as lack of any residual invasive disease in primary tumor and regional lymph nodes. We used chi-square and Fischer's exact test for the statistical analysis.ResultsWe prospectively enrolled 239 patients. Median age was 51.2 years and the median follow up was 26 months. Pleomorphic calcifications were more often found in HER2 positive patients (22/37) vs. HER2 negative (71/202), P = 0.005, as well as in COX2 positive patients (28/57), P = 0.044. There were no significant associations between PC and ER or PgR. PC were less prevalent in triple receptor negative patients (11/55)[20%] as compared to receptor positive patients (84/188), P = 0.001. We found PC predicted DCIS to be associated with invasive cancers (27/51)[53%] compared to those who showed no DCIS associated with their invasive breast cancer (57/157) [36%] (P=0.035).When evaluating response to therapy, patients with PC on MG were more likely to have a pCR (6/18) [33%] as compared to those who showed absence of pleomorphic calcifications (2/34)[ 6%], following neoadjuvant chemotherapy, P= 0.015.ConclusionsPleomorphic calcifications were significantly associated with HER2 and COX2 positive primary tumors. Patients with PC were also more likely to have a pCR after systemic therapy. Information regarding PC on MG may be helpful in predicting tumor marker status and response to therapy.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 2027.