Reynolds, Carol

Key Points HSCT after PD-1 blockade is feasible, although may be associated with increased early immune toxicity. PD-1 blockade may cause persistent depletion of PD1+ T cells and alterations in T-cell differentiation impacting subsequent treatment.

Abstract Background: Women with benign breast disease are at elevated breast cancer risk. In order to accurately predict a woman's individual risk of breast cancer, a breast cancer risk-prediction model is needed that incorporates significant breast cancer risk factors. This report describes two factors: tissue based assessment of lobular involution, and radiological marker- mammographic density (MD). Lobular involution, or physiologic atrophy of the breast glandular epithelium, is inversely associated with breast cancer risk. MD is a strong positive risk factor for breast cancer. With increasing age, the extent of lobular involution increases while MD decreases. However, it is unclear whether involution and MD represent independent breast cancer risk factors. We examined breast cancer risk associated with lobular involution and MD in women with benign breast disease (BBD) to determine whether these features are independently associated with breast cancer risk.Methods: Using the Mayo Clinic Surgical and Pathology Indices, 9376 women ages 18 to 85 with benign excisional breast biopsy between January 1, 1967 and December 31, 1991 were identified and formed the Mayo BBD cohort. We studied a sub-cohort of women diagnosed with BBD between 1985 and 1991 (when MD was clinically assessed and recorded) who had a mammogram within 6 months of the BBD diagnosis. Breast cancer outcomes were determined through the Mayo medical records and a study-specific questionnaire. Lobular involution extent was assessed in background tissue as 'none' (0% lobules involuted), 'partial' (1-74% lobules involuted) or 'complete' (≥75% lobules involuted). MD was classified as Wolfe's parenchymal pattern (PP) as N1/ fatty; P1; P2; and DY/ homogenously dense. Hazard ratios and confidence intervals were calculated using Cox regression analyses, adjusting for confounders: age, parity, BMI, BBD histology, menopausal status, family history, PP and involution extent.Results: A total of 2666 women in the Mayo BBD cohort, with biopsies between 1985 and 1991, had a mammogram within 6 months of the breast biopsy. The mean age at biopsy was 54.6 years. After a mean follow-up of 13.3 years, 172 (6.5%) women developed breast cancer. After adjustment for PP and other confounders, women with no or partial involution had elevated risk compared to women with complete involution (HR 2.62 [95% CI 1.39, 4.94] for no involution and 1.61 [95% CI 1.03, 2.53] for partial involution; complete involution as reference group; p for trend 0.003). Moreover, women with dense breasts were at greater risk compared to women with nondense breasts (HR 1.67 [95% CI 1.0, 2.73] for DY pattern, 1.96 [95% CI 1.2 – 3.21] for P2, 1.23 [95% CI 0.67, 2.26] for P1; N1 category as reference group; p for trend 0.02). Multivariate analyses also showed that women with the combination of no involution and dense breasts had greater risk compared to those with complete involution and nondense breasts (HR 4.08 [95% CI 1.72, 9.68]).Conclusion: Lobular involution and MD are both risk factors for breast cancer; this report is the first to demonstrate that each provides unique information about breast cancer risk. These findings emphasize the potential for inclusion of both these factors in future breast cancer risk-prediction models. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 6064.

Abstract Abstract #6037 Background: Tamoxifen (Tam) is biotransformed to the potent antiestrogen, endoxifen, by the CYP2D6 enzyme. We previously demonstrated that patients (pts) receiving adjuvant TAM with impaired CYP2D6 metabolism due to CYP2D6 (*4) and/or concurrent administration of a CYP2D6 inhibitor had a higher risk of recurrence. Other studies suggest CYP2C19*17 (Schroth JCO 2007) and SULT1A1*2 (Nowell JNCI 2002) may be associated with treatment outcome. With extended follow-up, we sought to evaluate the importance of comprehensive CYP2D6 genotyping as well as the potential association between CYP2C19*17 and SULT1A1 copy number with clinical outcome in pts randomized to TAM in NCCTG 89-30-52.
 Methods: Using DNA derived from paraffin embedded sections, CYP2D6 and SULT1A1 genotype were determined using quantitative multiplex PCR and CYP2C19 by sequencing. Pts administered the following CYP2D6 inhibitors (fluoxetine, paroxetine, sertraline, cimetidine, amiodarone, doxepin, ticlopidine and haloperidol) were considered as intermediate (IM) or poor metabolizers (PM) based on the potency of CYP2D6 inhibition. CYP2D6 phenotype was defined as follows: extensive metabolizers (EM) were pts not administered an inhibitor who did not carry a null allele (*3, *4, *6) and who were not homozygous for an IM allele (*10, *17, *41). CYP2D6 IM were either heterozygous for a null allele or homozygous for an IM allele but not administered an inhibitor or CYP2D6 EM administered a weak inhibitor. PM were pts homozygous for a null allele, or any patient administered a potent inhibitor. The association between genotype or CYP2D6 phenotype and clinical outcome was determined using the log-rank test. Multivariate Cox modeling was performed using traditional prognostic factors.
 Results: The median follow-up of living pts is now 14.5 years. Of 256 pts. randomized to TAM, genotype was determined for CYP2D6 (n=210), CYP2C19*17 (n=170), and SULT1A1 (n=169) with the following allele frequencies: CYP2D6 *3 (.02), *4(.20), *6 (.01), *10 (.03), *17 (.00), *41(.08), and CYP2C19*17 (.22). The frequency of SULT1A1 copy number alleles (CNA) was 1 (4%), 2 (67%), 3 (20%), and 4+ (9%). 14/227 patients (6%) were administered an inhibitor. A multivariate analysis accounting for nodal status and tumor size demonstrated that compared to CYP2D6 EM, CYP2D6 PM had significantly shorter time to recurrence (TTR) (HR 4.0, p=0.001) and DFS (HR 2.0, p=0.02) and CYP2D6 IM tended to have shorter TTR (HR 1.8, p=0.08) and DFS (HR 1.4, p=0.10). DFS did not differ by SULT1A1 copy number (p=0.62) or CYP2C19 *17 (p=0.47)
 Conclusion: Long term follow-up of pts in NCCTG 89-30-52 confirms the importance of CYP2D6 metabolism and further demonstrates the importance of comprehensive genotyping and phenotyping with CYP2D6 inhibitors. We could not identify an association between CYP2C19*17 or SULT1A1 copy number with recurrence but further evaluation is needed in larger cohorts. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6037.

Abstract Abstract #4033 Background: Aromatase activity within the breast is a source of estrogen that may cause breast cancer. Mammographic density (MD) is a risk factor for breast cancer whose biologic basis is unknown. Our study compared aromatase expression in tissue from dense and non-dense areas of the breasts of healthy volunteers.
 Methods: Participants were 40+ yrs, had a screening mammogram with visible MD, no history of cancer and were not on endocrine therapy. Ultrasound-guided core biopsies were done within 6 months of mammography to obtain three paired cores from mammographically dense and non-dense regions of the breast. Immunostaining for aromatase expression employed the streptavidin-biotin amplification method using the recently developed 677 mouse monoclonal antibody. Immunoreactivity (IR) was scored in terms of proportion of cells staining positive for aromatase (PPC) (0=<1%, 1=1-25%, 2=26-50%, 3=51+% (and 4=75%+ for adipocytes)) and relative immunointensity (0=none, 1=weak, 2=moderate, 3=intense) for each cell type (stroma, normal ductal epithelium, adipocytes). A composite score weighting the PPC by their relative intensity (range 0-9; 0-12 for adipocytes) was also calculated. The sum of the composite score across the three cell types provided a global assessment of aromatase IR. Repeated measures analyses evaluated differences in aromatase IR for dense compared to non-dense tissue within and across cell types. Parameter estimates (β) indicated the average difference between dense and non-dense IR.
 Results: 18 (37%) of the 49 participants were premenopausal (median age 46 yrs). Summing across cell types, the global composite score showed increased aromatase IR on sections sampled from dense vs. non-dense regions (β=5.3,p<0.001). This global difference reflected increased aromatase IR in the stroma and normal ductal epithelium from dense sections (vs. non-dense). For 42 women with >1% stromal cells on each section, there was evidence for increased IR on dense sections as indicated by the greater PPCs (β=0.9), relative intensity (β=0.7) and composite score (β=2.7)(p's<0.001). Similarly, for 20 women with >1% normal ductal epithelium in both dense and non-dense sections, there was a greater composite score (β=1.4,p=0.004) for cells on dense sections although differences for PPC (β=0.3,p=0.11) and relative intensity (β=0.3,p=0.09) did not reach statistical significance. No differences were seen in IR for adipocytes from the two density regions (46 women). Findings were unchanged with adjustment for covariates, including proportions of each cell type per section.
 Conclusions: There is strong evidence for increased aromatase expression in the stromal and normal ductal epithelium of dense vs. non-dense tissue. These results support ongoing research into mammographic density as a biomarker of effect of aromatase inhibitors. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4033.

The authors describe the case of a 36-year-old man with gynecomastia who was previously treated with liposuction of the breast for cosmetic purposes. Histologic examination of a subsequent excisional biopsy revealed nests of displaced epithelial cells in adipose tissue. Epithelial cell displacement is a well-known risk of core needle biopsies and fine-needle aspirations of breast lesions. However, to the authors’ knowledge, epithelial displacement in gynecomastia after liposuction, mimicking invasive ductal carcinoma, has not previously been reported.