Abstract 133: Treatment related breast cancer disease specific survival improvement over time limited to estrogenreceptor negative patients: 1990-2004.
Authors: Kaplan Henry G. , Malmgren Judith , Atwood Mary 
Published: August 2014

Background. It is unclear if improvement in breast cancer (BC) disease specific survival (DSS) over the past two decades is related to increased mammography detection or more effective treatments.

Methods. From our institutional breast cancer registry database we identified BC stage II and III patients age 50-59 given adjuvant chemotherapy for diagnosis years 1990-2004. Information in the database is chart abstracted and variables include method of detection, diagnosis and treatment with patients followed over time for subsequent recurrence and vital status. We compared disease specific survival (DSS) by 5 year intervals and stratified by detection method and estrogen receptor status (ER). Method of detection was categorized as patient (PtD) or mammography (MamD) detected as recorded in the chart by the physician at time of diagnosis (n=483). Physician detected (n=50) and cases untreated with chemotherapy (n=52) were excluded. Cox regression was used to test for significant predictive variables and the Kaplan Meier method for DSS stratified analysis.

Results. Of the 483 cases 42% were MamD and 58% were PtD with 82% stage II and 18% stage III cancer. Average length of follow up was 10.46 years, range 8.11-17.21 years. Cox regression analysis results for comparative change in DSS by 5 year intervals (1990-94, 1995-99, 2000-04) were significant for ER status (p&lt;.001) and detection method (p=.001). Overall 5 year DSS rates were 1990-94 = 81%, 1995-99 = 91% and 2000-04 = 95% with a significant difference between 1990-94 and 2000-04 (p=.002). In analysis stratified by detection method there was no significant difference in 5 year DSS by diagnosis year interval for MamD BC (1990-94=96%, 1995-99=98%, 2000-04=98%) but there was significant improvement for PtD BC (1990-94=75%, 1995-99=85%, 2000-04=91%, p=.011). Further stratification of PtD BC by ER status revealed significant improvement in 5 year DSS was confined to the PtD ER negative patients comparing years 1990-94 (55%) to 1995-99 (77%) (p=.042) (n=89). Mammography detected ER positive (n=199) and negative (n=32) cases had &gt;90% 5 year DSS rates over all three time intervals with no significant changes by diagnosis year.

Conclusions. In our cohort, better disease specific survival over time was related to both detection method and estrogen receptor status. Specific improvement over time was confined to patient detected estrogen receptor negative disease cases with no change in mammography detected cases DSS by either positive or negative estrogen receptor status. Survival improvement is coincident with the introduction of taxol for adjuvant chemotherapy treatment in 1994.

Citation Format: Henry G. Kaplan, Judith Malmgren, Mary Atwood. Treatment related breast cancer disease specific survival improvement over time limited to estrogenreceptor negative patients: 1990-2004. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 133. doi:10.1158/1538-7445.AM2013-133