1712. Screening Mammography in Older US Women
Authors * Denotes Presenting Author
  1. Ashley Bragg *; MD Anderson Cancer Center
  2. Sarah Martaindale; MD Anderson Cancer Center
  3. Davis Teichgraeber; MD Anderson Cancer Center
  4. Toma Omofoye; MD Anderson Cancer Center
  5. Gary Whitman; MD Anderson Cancer Center
Screening mammography guidelines for older women vary significantly between organizations, creating confusion for patients and providers. Additionally, the United States Preventive Services Task Force recommends that women over 75 may opt out of ongoing screening. In this IRB approved, retrospective study, we evaluate breast cancers diagnosed in women in 2 age groups: 65 versus 75-77 years-old, to determine cancer characteristics. This objective is to influence screening mammography guidelines in older patients.

Materials and Methods:
A retrospective review was performed of patients over age 65 presenting with a newly diagnosed breast cancer from 1990-2020. Two age groups of women were evaluated, 65-year-old women and 75-77-year-old women. 499 65-year-old women were evaluated as well as 500 women aged 75-77 years. Patients were categorized as presenting for screening versus diagnostic mammography and according to the presenting symptoms. Tumors were characterized based on mammographic and ultrasound findings, size at presentation, and nodal status. Tumors were clinically categorized as T0, T1, T2, T3, T4, and Tis using mammogram and ultrasound findings and the Eighth Edition AJCC TNM breast cancer staging system. The regional nodal basins, including the axillary, internal mammary and, if applicable, supraclavicular regions were evaluated with ultrasound. Suspicious lymph nodes were biopsied. Nodal status was categorized as N0, N1, N2, or N3 by ultrasound findings and applicable biopsy results per the TNM system.

In the 65-year-old patients, 3/499 (0.60%) were T0 with no suspicious imaging findings on mammography or ultrasound, 217/499 (43.5%) were T1, 157/499 (31.5%) were T2, 35/499 (7.0%) were T3, and 33/499 (6.6%) were T4. 54/499 (10.8%) had calcifications only on imaging and were categorized as Tis. Nodal status was evaluated in 468 patients in the 65-year-old patient group. 345/468 (73.7%) were N0, 85/468 (18.2%) were N1, 9/468 (1.9%) were N2, and 29/468 (6.2%) were N3. 258/499 (51.7%) of the 65 year-old patients presented for screening and 241/499 (48.3%) for diagnostic mammogram. In the 75-77-year-old patients, 1/500 (0.2%) were T0, 217/500 (43.4%) were T1, 155/500 (31.0%) were T2, 25/500 (5.0%) were T3, and 31/500 (6.2%) were T4. 71/500 (14.2%) were categorized as Tis. Nodal status was evaluated in 459 patients in the 75-77-year-old patient group. 338/459 (73.6%) were N0, 89/459 (19.4%) were N1, 7/459 (1.5%) were N2, and 25/459 (5.4%) were N3. 69/500 (53.8%) of the 75-77 year-old patients presented for screening and 231/500 (46.2%) for diagnostic mammogram.

Our study demonstrates similar presentations, tumor characteristics, tumor sizes, and nodal status in each age group. Given the low cost and the feasibility of obtaining screening mammograms in older women, and that more women are living longer and more engaged lives, it is reasonable to recommend annual screening mammography in women 75 years and older who are in good health. This may result in breast cancers being detected earlier, at a more treatable stage, and with a greater likelihood of survival.