Background: Obesity is associated with an increased risk of breast cancer (BC) recurrence and decreased survival, also in case of adjuvant endocrine therapy. It is still not clear whether the activity of aromatase inhibitors and tamoxifen (T) given as adjuvant therapy is affected by body mass index (BMI), although both drugs are widely prescribed. In this analysis, we explored the outcome of TEAM patients (pts) treated with exemestane (E) versus T (2.75 yrs), and with E versus T followed by E (T/E) (5 yrs) in relation to BMI. Patients and Methods: The TEAM trial is a randomized, international phase III study in postmenopausal hormone sensitive early BC pts comparing the activity and safety of adjuvant E (25 mg daily) or the sequence of T (20 mg daily) followed by E (T/E), both regimens given for five years. WHO BMI definitions were used: normal 18.5-24.9 kg/m2, overweight 25-30 kg/m2, obese >30 kg/m2. Disease-free survival (DFS) and overall survival (OS) were calculated by Kaplan-Meier method; results were compared by using the log-rank test and Cox proportional hazard modelling adjusted for country. Results: Weight and height was known in 4741 pts. Mean BMI was 26.9 kg/m2 (SD 4.9); 39% had a normal BMI, 36.9% overweight, and 23.3% of pts was obese. Underweight pts (n=41, 0.9%) were excluded from further analysis. At 2.75 yrs (E vs T) disease relapse in normal weight, overweight and obese pts using E was observed in 8.1%, 6.8% and 7.5% respectively (p=0.57), and in 9.1%, 8.8%, and 12.5%, respectively (p=0.06) of pts using T. The hazard ratio (HR for risk of relapse on E vs T) in the three subgroups was 0.91 (95%CI 0.66-1.24), 0.78 (95%CI 0.55-1.089), and 0.57 (95%CI 0.39-0.84, p=0.004), respectively. At a median follow-up of 5.1 years, disease relapse in normal weight, overweight and obese pts using E occurred in 14.8%, 15.1% and 15.1%, respectively; and in pts using T in 17.0%, 16.9%, and 18.3%, respectively. Regarding DFS, the HR in normal weight, overweight, and obese pts was 0.87 (95%CI 0.69-1.10), 0.88 (95%CI 0.70-1.11), and 0.75 (95%CI 0.56-1.01, p=0.058), respectively, and with respect to OS 0.87 (95%CI 0.65-1.15, p= 0.32), 0.89 (95%CI 0.67-1.18, p= 0.43), and 0.71 (95% CI 0.51-1.01, p= 0.053), respectively. Conclusions: After 2.75 years more disease events were observed in obese women using tamoxifen, which was not seen in obese exemestane users, whereas at 5 years these differences in disease recurrences disappeared in this group. In contrast to recent reports, there seems to be a difference regarding the influence of a high BMI on recurrence rate between tamoxifen and the aromatase inhibitor exemestane. Further research on this topic is warranted. Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr S2-3.

Background: Breast cancer patients comprise a prognostic heterogeneous group. Stroma-tissue surrounding cancer cells plays an important role in tumor behavior. The prognostic value of the tumor-stroma ratio was evaluated.Material and Methods: A cohort of 574 patients with early breast cancer, primarily treated by surgery between 1985 and 1994 was analyzed. The percentage of intra-tumoral stroma was visually estimated on haematoxylin-eosin-stained histological sections from primary tumor tissue by two observers. Patients with more than 50% intra-tumor stroma were quantified as stroma-rich and patients with less than 50% intra-tumor stroma as stroma-poor.Results: Of all tumors, 68% were classified as stroma-rich and 32% as stroma-poor. Cohen's kappa coefficient revealed an almost perfect agreement in classification (kappa=0.85; 94% concordance in classification) between the two observers. For the total group of patients, stroma-rich tumors had a shorter relapse free period (RFP) (Hazard ratio (HR) 1.62; 95%CI 1.23-2.13; p=0.001) and overall survival (OS) (HR1.29; 95%CI 1.03-1.60; p=0.025) compared to stroma-poor tumors. Tumor-stroma ratio was an independent prognostic parameter for all patients (p<0.001) and in stratified analysis for patients that received systemic treatment. Importantly, within the triple-negative-cancer (TNC) subpopulation, patients with stroma-rich tumors had a 3.19 times higher risk of relapse (p=0.003) compared to patients with stroma-poor tumors, independently of grade and lymph node status. Five year RFP-rates for patients with stroma-rich compared to stroma-poor tumors were 56% and 81% respectively.Discussion: Tumor-stroma ratio was an independent prognostic factor for RFP in breast cancer patients, especially in TNC. The tumor-stroma ratio is easy to apply, of low cost and reproducible. It is a candidate parameter that can easily be implemented in routine daily diagnostics to optimize risk-stratification for breast cancer patients and should therefore be considered to be implemented in standard pathology reports. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3049.

#21 Background In the last decade, use of adjuvant hormonal treatment increased as well as its duration. Aromatase inhibitors are associated with a minimal increase of disease free survival compared to tamoxifen. Both therapies are associated with different side effects which can affect quality of life (QoL). Therefore, it is necessary to compare the QoL of patients using these therapies. We compared the QoL of women participating in the Dutch Tamoxifen Exemestane Adjuvant Multicentre (TEAM) Trial.
 Patients and Methods The Dutch TEAM trial included 2754 postmenopausal early breast cancer patients who were randomised between five years of exemestane or 2.5-3 years of tamoxifen followed by 2.5-2 years of exemestane. A total of 742 patients were invited onto the QoL subprotocol. At one (T1) and two (T2) years after start of hormonal treatment, patients were ask to fill in questionnaires. This questionnaire contains the European Organisation for Research and Treatment of Cancer (EORTC) QLQ C30 and the EORTC BR23 questionnaires, supplemented with Functional Assessment of Cancer Therapy - Endocrine Subscale (FACT-ES) questions covering endocrine symptoms. The endpoint was the difference in QoL between patients receiving tamoxifen or exemestane.
 Results Questionnaires were completed by 543 patients at T1 and 83% of these returned the questionnaire of T2. There were no significant differences in physical functioning, role functioning, cognitive functioning, emotional functioning, body image, breast symptoms, arm symptoms and endocrine symptoms between both treatment groups at T1 nor at T2. Patients receiving exemestane had significantly less sexual enjoyment (difference of 9 points on a 0-100 scale; p=0.004) and more insomnia (difference of 8 points; p=0.005) compared to patients receiving tamoxifen at T1. At T2, there was no statistically significant difference in sexual enjoyment (difference of 4 points; p=0.287). However, patients receiving exemestane reported significantly worse sexual functioning (difference of 5 points; p=0.020) and still more insomnia (difference of 8 points; p=0.004).
 Conclusion Patients using exemestane reported less sexual enjoyment and more sexual functional problems than patients using tamoxifen. This may be explained by the fact that specific side effects of exemestane (e.g. vaginal dryness) can cause less sexual enjoyment which can result in a decreased sexual functioning. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 21.

#1154 Background Aromatase inhibitors (AIs) given to women with early breast cancer may adversely affect bone metabolism. We studied the effect of exemestane (E) on bone mineral density (BMD) and bone turnover and compared it to the effect of tamoxifen (T) treatment in a group of women participating in the Dutch and Belgian Tamoxifen Exemestane Adjuvant Multicentre (TEAM) trial. In this trial, postmenopausal women with hormone sensitive early breast cancer (n=3168) were randomised between 5 years E or 2½-3 years T followed by 2½-2 years of E.
 Methods In this subprotocol, 87 women were followed for two years. Patients with bone diseases were excluded. Total hip and lumbar spine BMD were assessed at baseline and after 1 and 2 years. The bone resorption marker cross-linked telopeptide of type-I collagen (CTX) and the bone formation marker N-terminal propeptide of type I collagen (PINP) were measured in fasting serum at baseline and after 3, 6, 12 and 24 months.
 Results At baseline, there was no difference in total hip (E: 0.85g/cm2, T: 0.80g/cm2; p=0.642) and lumbar spine BMD (E: 0.99g/cm2, T: 1.02g/cm2; p=0.545) between both groups. After 2 years, there were no significant changes in total hip BMD (E: 0.02 g/cm2 95%CI -0.05;0.08, p=0.849; T: 0.03 g/cm2, 95%CI -0.02;0.09, p=0.466) and in spine BMD (E: -0.02 g/cm2 95%CI -0.11;0.06, p=0.834; T: 0.02 g/cm2 95%CI -0.05;0.10, p=0.747). At baseline, there was no difference in serum CTX (E: 0.34ng/mL, T: 0.29ng/mL; p=0.271) and P1NP (E: 57ng/L, T:58ng/L, p=0.973) between both groups. After 2 years of treatment, serum CTX increased, although not significantly in the E group (20%, 95%CI -6%;54%, p=0.223) while it decreased significantly in the T group (-40%, 95%CI -23%;-53%, p<0.001). At 24 months, the CTX was 0. 44ng/mL (E) and 0. 18ng/mL (T). Serum P1NP did not change in the E group (-2%, 95%CI -20%;19%, p=0.837) but decreased significantly in the T group (-48%, 95%CI -36%;-58%, p<0.001). At 24 months, the P1NP was 55ng/L (E) and 28ng (T).
 Conclusion Although there was a trend for an increase in bone resorption with E treatment, this was not significant and was not associated with a decrease in BMD. The magnitude of the reported negative effect of aromatase inhibitors on bone metabolism in studies using T as comparator treatment may be overestimated by the effect of T on bone turnover. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 1154.

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