Abstract P6-02-07: Persistence of patient detected breast cancer in the mammography screening era: 1990-2013
Authors: Malmgren J , Atwood M , Kaplan H 
Published: May 2016

Background: It is estimated from most current National Health Interview Study data that 72% of women age 50-74 have had a screening mammogram in the past 2 years which is significantly less than the Healthy People 2020 goal of 81%. It is not known to what extent breast cancer (BC) is patient diagnosed vs. mammography diagnosed in the community.

Methods: We examined method of breast cancer diagnosis among a large institutional cohort of age 50-74 first primary breast cancer patients with no history of prior cancer identified between 1990 and 2013 (n=5736). Patients were all biopsy proven BC with diagnostic data abstracted from the charts and recorded in our breast cancer specific registry database. Chart recorded detection method was by patient presenting with a personally detected breast symptom (PtD) (n=1729), physician discovered physical findings (PhysD) (n=260) or by routine mammography in absence of physical complaints or findings (MammD) (n=3747). It is not known if patients participated in screening programs. Patients with unknown or other BC diagnosis method were excluded (n=91). BC staging was converted to AJCC 7 to remove inconsistency over time. Pearson chi square was used for bivariate comparisons and logistic regression for identification of characteristics associated with patient detection.

Results: Rate of patient detection of all stage BC decreased over time from 43% in 1990 to 27% in 2013 (chi square = 119.45, p&lt;.001) (n= 5736). Rate of detection of invasive BC (excluding stage 0) decreased over time from 45% to 33% (chi square = 87.14, p &lt;.001) (n=4690). Stage shift to lower stage disease occurred over time with the decrease in PtD BC and increase in MamD BC. Stage 0 BC increased from 4% to 24% (20%), stage I BC decreased from 57% to 44% (13%) and stage III BC decreased from 15% to 7% (8%) (chi square = 232.51, p&lt;.001). Constant over time, stage II, III and IV breast cancer were most often patient detected (stage II 49%, stage III 70%, stage IV 81%, chi square = 1333.03, p&lt;.001). In a logistic regression model adjusted for diagnosis year using PtD vs MamD BC as the outcome, non-white race, younger age (50-59) and all invasive breast cancer stages (not 0/DCIS) were significantly related to an increased risk of BC being diagnosed by the patient [non-white RR =1.32, 95% CI = 1.11, 1.59; age 50-59 RR = 1.43, 95% CI = 1.22, 1.69; stage I RR = 3.55, 95% CI = 2.73, 4.63; stage II RR = 15.42, 95% CI = 11.79, 20.17; Stage III RR = 38.61, 95% CI = 28.20, 52.87; Stage IV RR = 133.72, 95% CI = 61.89, 288.92].

Conclusions: Our results indicate improvement in mammography screening may be obtained by reaching out to women of non-white race and younger screening recommended age groups. Higher stage disease requiring extensive treatment for cure or diagnosed as incurable metastatic disease is significantly associated with patient detection. The number of higher stage patient detected cancers indicates a portion of the population may not be screened and are at risk for serious disease in an era when mammography screening is widely available.

Citation Format: Malmgren J, Atwood M, Kaplan H. Persistence of patient detected breast cancer in the mammography screening era: 1990-2013. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P6-02-07.