Background: Prognostic factors, such as breast cancer (BC) genomic profile, are cornerstone for the understanding of the disease, especially in the orientation of its treatment. The majority of studies reporting BC genomic profile were conducted in developed countries. Research in the developing world is needed, in order to investigate if BC profile in these countries is similar to the one seen in the developed world. Moreover, it is important to evaluate possible differences in the genomic profile between pre-and post-menopausal women. Finally, it is also important to appraise if there was any temporal trend in BC genomic profile in the last decade. Methods: A consecutive sample of patients who were diagnosed with BC between 2000 and 2010 were analyzed. All patients were diagnosed and treated at Núcleo Mama Moinhos, a specialized BC service in South Brazil. Comparisons were made between women below and above the age of 50, and between the period of 2000-2005 and 2006-2010. The Fisher exact test was used for comparisons. Ki-67 was considered as positive when > 5%. Results: 439 patients were included. Mean age was 55 ± 13 years, 37% of the sample was younger than 50 years old and 10% than 40 years old. 57% were diagnosed between 2000-2005 and 43% between 2006-2010. Tumor staging was as follows: 61% stage 0/I, 22% stage IIA, 9% stage IIB, 7% stage III and 1% stage IV. Median tumor size was 1.6 cm (IQR 1.0 — 2.5), 26% of patients had positive lymph nodes. 75% were invasive ductal carcinomas and 10% were in situ ductal carcinomas. Tumor histologic grades were as follows: 15% grade I, 42% grade 2 and 22% grade 3. Surgery type was mastectomy in 43.5% and setorectomy in the remainder. 56% of patients were submitted to chemotherapy, of which 25% were neoadjuvant. Regarding the genomic profile, 82% of the sample had positive estrogen receptor (ER) or progesterone receptor (PR), 18% were HER2 positive, and 11% were triple negative. Ki 67 was positive in 68% of the sample, median value was 10% (IQR 5% — 20%); p53 mutation was seen in 26%. When compared to patients diagnosed between 2000-2005, the sample from 2006-2010 had a lower prevalence of hormone receptors (76% vs 86%, p = 0.01) and a higher proportion of triple negative cases (16% vs 8%, p=0.01). This difference was more marked in women below the age of 50 (6% until 2005 and 18% afterwards, p = 0.02). There were no other temporal trends in the other evaluated variables (staging, histologic grade and type, age, HER2, type of surgery). In the comparison of women diagnosed after versus before 50 years of age, the former had a more favorable staging: 86% were in stages 0/I/IIA, as compared to 78% in the latter (p=0.03). Conclusions: The profile seen in this population has some similarities with other series from developed countries. The increase in triple negative and hormone negative tumors in women older than 50 is worrisome and does not reflect the common sense that the large majority of cases in this age group are hormone sensible. Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P3-12-13.

Introduction: The NMPOA cohort started in 2004 with the purpose of testing a breast screening model for underserved women in limited resource countries. In the city of Porto Alegre (South Brazil with 1.5 million population), breast cancer incidence rate is 127/100.000 (Brazilian NCI,2010) with increasing mortality due to 45% of Stage III and IV and no public health care early detection program, it was mandatory to test the feasibility of an organized screening program for women with very low income and level of education (64% under 6 years of schooling). In this scenario, there was always a concern of over diagnosis that will increase costs (more biopsies and surgeries) and under diagnosis by the radiologists involved in the program. We present here the results of all breast biopsies performed in this period, and its correlation with the attributed BI-RADS classification in order to optimize care and costs. Also, this study has a long term proposal and other results have been published concerned to the baseline profile of the population (Cancer Epidemiol Biomarkers Prev. 2010 Oct;19(10):2673–9. Epub 2010 Aug 17). Methods:Since April 2004, 5592 women from 40 to 69 years were enrolled in the program and underwent to clinical breast exam and annual mammography screening at NMPOA. Initially, lesions were classified as B1, B2 or B0. After complementary views or exams, B0 was classified as B3, B4 (A, B or C) or B5. B4 and B5 were considered positive tests and immediately submitted to biopsy (open surgical or ultrasound guided core biopsy). B3 was followed according to recommended in BI-RADS fourth edition, and subsequently classified as benign (annual follow up) or suspicious findings (biopsy performed). The evaluation included histological analysis of breast biopsy specimens by two independent pathologists. Predictive positive value (PPV), predictive negative value (PNV) and accuracy (Acc) were calculated. Results: A total of 259 breast lesions were initially classified as BI-RADS 0 (recall rate of 2.8%), and further classification of these was: 166 B3 (64.1%), 60 B4 (23.2%) and 33 B5 (12.7%). Thirty seven B3 (14.3%) were considered suspicious after 6 months and submitted to biopsy. Correlation results of the 130 biopsies performed are summarized on [Table1]. PPV of 63.4% (52.8%-73.1%), PNV of 97.3% (85.8%-99.9%) and an Acc of 73.1% were observed. In this sample, 71.7% of BC were ductal invasive carcinoma, 11.7% ductal carcinoma in situ, 5% lobular invasive carcinoma and 11.6% were other types of neoplasia. Conclusion: Recall rate is in accordance with the medical audit benchmarks recommended of less than 10% published in BI-RADS fourth edition. NMPOA is model for limited resource countries in breast cancer imaging diagnosis. The radiologists involved in the program are classifying breast lesions in accordance with the established parameters, with a high accuracy in diagnosis. Even though we are dealing with a poorly educated cohort not used to any form of screening, our adherence is 57% in 12 months and 71% in 24 months. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P5-09-01.