Short Term Cancer Risk

Transcription

1 in a Cohort of 2312 Women with High Risk Breast Lesions Kubat E 1, Puligandla B 2, Collins L 3, Jiang SF 4, Callahan M 5, Kutner S 6, Habel L 4, Shim V 1 1 Surgery, Kaiser Permanente, Oakland, CA; 2 Pathology, Kaiser Permanente, Oakland, CA; 3 Beth Israel Deaconess Medical Center, Boston, MA; 4 Division of Research, Kaiser Permanente, Oakland, CA 5 Genetics, Kaiser Permanente, Oakland, CA; 6 Surgery, Kaiser Permanente, Santa Theresa, CA Eric Kubat M.D. PGY 2 Kaiser Permanente, Oakland CA Dept. of Surgery UCSF East Bay Background Increased use of mammographic screening has resulted in a growing number of women diagnosed with high risk breast lesions. No clear guidelines for treatment or follow up Reliable estimates of subsequent breast cancer risk are needed to develop these guidelines and assist patients and their physicians in decisions regarding risk reduction reduction strategies.

2 Aim To estimate incidence rates of subsequent breast cancer among women diagnosed in the community setting with a high risk breast lesion. Atypical ductal hyperplasia (ADH) Lobular hyperplasia (ALH) Lobular carcinoma in situ (LCIS) Methods Study population: Kaiser Permanente health plan members Community based diagnosis ( ) Atypical ductal hyperplasia (ADH) Lobular hyperplasia (ALH) Lobular carcinoma in situ (LCIS) 2312 eligible women ADH (n=1599) ALH (n=698) LCIS (n=226)

3 Methods Exclusion criteria Documented history of breast cancer Diagnosis based on fine needle needle aspirate No available pathology report Documented breast cancer within 6 months after diagnosis of high risk risk breast lesion Methods Follow up Pathology to confirm diagnosis Laterality, indication, histopathologic features. Cohort followed until one criterion met Diagnosis of a subsequent breast cancer invasive ductal (IDC), invasive lobular (ILC), and/or ductal carcinoma in situ (DCIS) End of membership December 2005

4 Methods Analysis Cohort of 2312 Women with High-Risk Breast Lesions Cumulative incidence curves were generated and Cox regression analyses were used to generate Relative Risk ratios. Patient Characteristics Characteristics* Full Cohort Cancer Cases Percent Age Years Age < Age Age Age Age Age Diagnosis Year Histology of High Risk Lesion ALH only ADH only LCIS only ALH+ADH ALH+LCIS ADH+LCIS ADH+AH, NOS ALH+ADH+LCIS Other Cancer Cases Full Cohort Cancer Cases 36 months 32 months *Diagnosis of High Risk Breast Lesion

5 ADH Laterality of High-Risk Lesion and Subsequent Cancer Invasive Ductal (N) Invasive Lobular (N) DCIS (N) Total (N%) Ipsilateral (58.2%) Contralateral (41.8%) 67 ALH Ipsilateral (58.3%) Contralateral (41.7%) 36 LCIS Ipsilateral (42.9%) Contralateral (52.1%) 21

6

7 Relative Risk of Any Cancer (Adjusting for Age) Total (N) Cases (N) Relative Risk 95% CI P Value ADH Reference 1 ALH LCIS Relative Risk of Invasive Cancer (Adjusting for Age) Total (N) Cases (N) Relative Risk 95% CI P Value ADH Reference 1.0 ALH LCIS

8 Results 123 women with High Risk lesions developed DCIS or invasive breast cancer. ADH / ALH, approximately 60% of cancers were in the ipsilateral breast LCIS approximately 40% of cancers were ipsilateral. Results Women 50+ years (5 year outcomes) Invasive Ductal Invasive Lobular Carcinoma Carcinoma LCIS 8% 2% ALH 4% 1.5% ADH 4% <1.5% ALH + ADH 7% 1%

9 Results Adjusting for age, risk of subsequent cancer among women with LCIS was approximately 2x that for women with ADH. Risk of subsequent cancer was similar among women with ADH or ALH. Results Patients aged years with atypical hyperplasia (ADH or ALH) have approximately 3x the risk of breast cancer at 5 years compared to similarly aged women in the general population (based on estimates from the Gail model).

10 Limitations Diagnoses were not confirmed by a standardized re review of slides. Number of cancers, especially when stratified by histology, was small and estimates are imprecise. Short term term follow up (<10 yrs, median 3.5 yrs) - Time to cancer is often protracted. Conclusions In this population of women diagnosed with high risk lesions, risk of subsequent invasive breast cancer was significant and varied by age and lesion histology Similar findings to prior studies

11 Acknowledgements Veronica Shim Laurel Habel Balaram Puligandla Laura Collins Sheng Fang Jiang Mary Callahan Susan Kutner Kaiser Foundation Research Institute