[144] Do Clinical and Pathologic Features of Ductal Carcinoma In Situ (DCIS) Vary with Patient Age? An Analysis of 657 Patients

L Collins, S Schnitt, N Achacoso, S Fletcher, L Nekhlyudov, R Haque, C Quesenberry, L Habel. Beth Israel Deaconess Med Ctr, Boston; Kaiser Permanente Northern California, San Francisco; Harvard Pilgrim Health Care, Boston; Kaiser Permanente Southern California, Los Angeles

Background: Prior studies have indicated that young age at diagnosis is associated with an increased rate of local recurrence (LR) among women with DCIS treated with breast-conserving therapy. However, whether this can be explained by differences in clinical or pathologic features of DCIS according to age has not been examined in detail.
Design: Among 3,037 women with DCIS treated with breast-conserving therapy between 1990-2001 at three health maintenance organizations in the Cancer Research Network, 657 were enrolled in a case-control study to assess clinical and pathologic factors associated with LR and had histologic sections available for review. In this analysis, we compared clinical and pathologic features of DCIS in women across four age groups: <45 yrs (n=111), 45-54 yrs (n=191), 55-64 yrs (n=160), and 65+ yrs (n=195).
Results: DCIS presented as a mammographic abnormality less often in younger than in older women (68% for women <45 yrs; 82% for those 45-54 yrs; 81% for those 55-64 yrs; 86% for those 65+ yrs) (p=0.003). Among the pathologic features analyzed, DCIS extent as determined by the number of low power fields (LPF) of DCIS was greater in younger than in older women (mean #LPF 18.6, 14.2, 10.8 and 11.3 for women <45, 45-54, 55-64 and 65+ yrs, respectively; p<0.001). In addition, cancerization of lobules was present more often in younger than in older women (77% for women <45 yrs; 73% for those 45-54 yrs; 66% for those 55-64 yrs; 50% for those 65+ yrs) (p<0.0001). Of note, neither architectural pattern, nuclear grade, nor comedo necrosis varied significantly according to age. Furthermore, there were no significant differences in the frequency of expression of ER, PR or HER2 by age. Using the combination of ER, PR and HER2 status as surrogates for molecular phenotype to categorize DCIS lesions as luminal A, luminal B, HER2 and basal-like types, we found no statistically significant association between age and molecular subtype of DCIS.
Conclusions: In women <45 yrs of age, DCIS more often presents with symptomatic disease, is more extensive, and more often shows cancerization of lobules than DCIS in older women. Whether these features explain in part the higher LR rate in young women with DCIS treated with breast conserving therapy requires further study.
Category: Breast

Tuesday, March 10, 2009 9:30 AM

Poster Session III # 27, Tuesday Morning