Tumor Size as a Surrogate End Point for the Detection of Early Breast Cancer: A 30-Year (1972?2002), Single-Center Experience in Southern Brazil

Abstract

The 30-year experience in improving detection of breast cancer in the Breast Unit of the Hospital de Clínicas, Federal University of Rio Grande do Sul, Brazil (1972-2002) is reported. We retrospectively analyzed the behavior of surrogate parameters of early breast cancer detection, such as the mean tumor diameter at diagnosis, clinical staging, as well as the percentage of breast conservative surgery along this period of three decades. From 2,103 identified women, 1,607 women met our criteria for study entry and had follow-up information, constituting our study cohort. Statistical tests were two-sided and considered significant at p < 0.05. There was a decrease of about 0.8 cm in the median tumor diameter over this 30-year period. The incidence of early-stage tumors increased progressively over time, and the percentage of patients presenting with stage I breast cancer doubled in 30 years. The Halsted procedure that represented 11.5% of surgeries in the 1970s is a very rare procedure nowadays (<1% of cases). Modified radical mastectomy was the procedure applied in about 50% of women with invasive breast cancer during these 30 years of observation. Notably, breast conservative surgery increased from 17.3% in the 1970s to 43.2% in the 2000s, while the decrease in tumor size and clinical staging was accompanied by an increased number of breast conservative surgical procedures. In geographic areas where coordinated preventive efforts are not thoroughly available, analysis of subsets of the patient population using tumor size as a surrogate represents an indirect way to observe long-term effects of prevention. The present study shows that tumor size is a surrogate for populations from developing countries too and gives scientific support for the design of continuous comprehensive programs of breast cancer prevention in this setting.

Strategies for Increasing Mammography Screening in Primary Care in Chile: Results of a Randomized Clinical Trial

“…In Chile, only 8% of breast cancer cases were diagnosed in situ stage in 2006 and, about 75% were diagnosed in stages II,III or IV (4). This low percentage of early detection among Chilean women is very similar to the percentages reported in other South American countries such as Brazil or Peru (6,7). Mammogram screening is an effective strategy to detect breast cancer in an early stage and reduce mortality rates when performed systematically to women 50 years and older (8).…”

Systematic Review of Breast Cancer Biology in Developing Countries (Part 1): Africa, the Middle East, Eastern Europe, Mexico, the Caribbean and South America

“…For the period 2000–2002 Menke et al showed that 76% (104/139) of cases occurred between the ages of 41 and 70 years [93]. …”

“…Menke et al reported on 1607 cases between 1972 and 2002 and described a significant reduction in the mean tumour size from 35 mm to 28 mm over this period [93]. For the period 2002–2002, 85% (118/139) of tumours were IDC while 10% (14/139) were ILC [93].…”

“…For the period 2002–2002, 85% (118/139) of tumours were IDC while 10% (14/139) were ILC [93]. For the same time period grade one tumours were reported in 19% (26/139) of cases, grade two in 46% (64/139) and grade three in 18% (25/139) [93].…”

Sexual function and chemotherapy in postmenopausal women with breast cancer

“…Fortunately, the number of new cases and the number of deaths are increasingly disproportionate as the population of breast cancer survivors experiences significant growth. This encouraging finding is largely due to early detection and to the therapeutic arsenal currently available [2,3]. …”