ER+PR- Breast Carcinomas Are More Frequently Associated with Older Patients, Larger Tumors and HER2 Positive Tumors
P Tai, J Wang, P Ding, P Tang. University of Rochester Medical Center, Rochester, NY; RTI Health Solutions, Research Triangle Park, NC
Background: Previous studies showed that ER+/PR- tumors are frequently seen in elderly women and in grade 2 ductal carcinomas. We also showed that these tumors are more frequently associated with bone metastasis and higher recurrence scores of 21-gene assay. In current study, we sought to investigate the clinicopathologic difference between ER+/PR-(PN) tumors and ER+/PR+(PP), ER-/PR-(NN), and ER-/PR+ (NP) tumors from a large data base.
Design: Nine hundred twenty consecutive cases of breast cancer between 1997 and 2008 were identified from our departmental file. Clinicopathological information such as patients' age, tumor type, tumor size, histologic grade, nuclear grade, lymph node status, and expression of ER, PR and HER2 were recorded. Statistical analyses were performed to compare among these 4 groups of tumors.
Results: Among the 920 cases, 546 (59.3%) were invasive ductal and ductal carcinoma in situ (IDC/DCIS), 190 (20.7%) were pure IDC, 118 (12.8%) were pure DCIS, and 66 (7.2%) were invasive lobular carcinoma (ILC). 165 cases (18.0%) were NN, 13 (1.4%) were NP, 101 (10.9%) were PN, and 641 (69.7%) were PP. The mean ages were 57.3, 53.1, 64.1, and 59.9 for NN, NP, PN, and PP, respectively, with PN being the oldest group and a p-value of 0.0004. The mean tumor sizes were 2.79cm, 1.85cm, 2.13cm, and 1.99cm for NN, NP, PN and PP, respectively, with a p-value of 0.0002. The most common histologic grades were grade 3 for NN (85%) and NP (55%), and grade 2 for PN (39%) and PP (40%), with a p-value less than 0.0001. The most common nuclear grades were grade 3 for NN (85%) and NP (70%); and grade 2 for PN (61%) and PP (57%), with a p-value less than 0.0001. HER2 over-expression was seen in 21%, 0%, 15%, and 9% in NN, NP, PN and PP, respectively, with a p-value of 0.0143. Lymphovascular invasion was seen in 26%, 8%, 15% and 17% in NN, NP, PN, and PP, respectively, with a p-value of 0.0351. Lymph node metastasis were similar among all 4 groups of tumors (p=0.2321).
Conclusions: PN tumors consist of 11% of all tumors, and are different from PP, NN, and NP tumors. They are more likely seen in older patients, with larger tumor and higher frequency of being HER2 positive compare to PP tumors.
Monday, March 22, 2010 1:00 PM
Poster Session II # 36, Monday Afternoon