Citations

Abstract Background: Microtubules are crucial for spindle formation during mitosis and for cellular proliferation. The antineoplastic effect of paclitaxel is mainly related to its ability to bind the beta subunit of tubulin, thus preventing tubulin chain depolarization and inducing apoptosis. Tubulins are expressed in human peripheral nerves and the binding of paclitaxel to tubulin may lead to neuropathy. Peripheral neuropathy is a common dose limiting toxicity of paclitaxel. We hypothesized that the occurrence of peripheral neuropathy may correlate with outcome (disease-free survival; DFS).Methods: This analysis sought to describe incidence of peripheral neuropathy following paclitaxel and its association to outcome (DFS) in patients who received paclitaxel (weekly x 12) in the adjuvant HER2+ intergroup trial N9831. Only eligible pts who initiated paclitaxel and did not have peripheral neuropathy at initiation of paclitaxel that were randomized to arms A (955 pts; chemotherapy alone) and C (889 pts; chemotherapy plus concurrent trastuzumab) of N9831 were included. Cox regression analysis stratified by ER/PR status and nodal status was used to compare DFS within arm between patients with and without peripheral neuropathy.Results: Out of 1844 eligible pts, 379 developed neuropathy (20.5%). For pts in arm A, those who developed neuropathy had better DFS than pts who did not (3 yr DFS: 86.2% vs 81.8%; HR 0.65; p=0.01), despite lower doses of paclitaxel in the pts with neuropathy. Grade of neuropathy did not appear to impact DFS. No statistical difference was noted for pts treated in the trastuzumab-containing arm (3 yr DFS: 92.8% vs 91.1% for pts with neuropathy vs not; HR 0.79; p=0.34). There were no differences in paclitaxel dose intensity between arms A and C.Conclusion: Patients with early stage HER2+ breast cancer who received adjuvant paclitaxel-containing chemotherapy in arm A and developed peripheral neuropathy had a better DFS than pts who did not develop neuropathy. This effect was possibly abrogated by the use of trastuzumab in Arm C. This side effect may represent effective bindings of paclitaxel to the target tubulin, lack of point mutations in tubulin at the paclitaxel binding site and/or lack of selective overexpression of β-III tubulin. This is a hypothesis generating study and additional analysis needs to be conducted from other large taxane-based trials.Partial support from Genentech and the Breast Cancer Research Foundation Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 2100.

Abstract Abstract #4020 Background: HER2 positive (HER2+) breast cancer accounts for 20% of all breast cancer and is an independent adverse prognostic factor. Breast magnetic resonance imaging (MRI) has been shown to identify additional mammographically occult ipsilateral (I/L) and contralateral (C/L) disease, however indications for preoperative MRI in patients with newly diagnosed breast cancer are not standardized. While invasive lobular cancer, younger patient age, and increased breast density have been suggested as routine indications, the role of preoperative MRI according to HER2 status has not been evaluated.
 Methods: All patients with invasive breast cancer who underwent preoperative MRI between January 2003 and December 2007 were reviewed. Retrospective chart review was performed to collect clinical, radiographic, and pathologic data. The incidence of additional I/L or C/L malignacy was calculated. Additionally, changes in surgical management because of MRI findings were recorded.
 Results: Of the 401 women with invasive breast cancer undergoing preoperative breast MRI, 51 (13%) had HER2+ tumors. The average age at the time of MRI was similar in both groups. HER2+ patients were more likely to have nodal disease, and tumors with higher rates of lymphovascular invasion or extensive intraductal components.
 
 When compared to HER2- patients, more HER2+ patients had additional ipsilateral MRI abnormalities. A second ipsilateral cancer was found in 31% of HER2+ patients compared to 25% of HER2- patients. When analyzed according to ER status, HER2+/ ER- patients were more likely to have an additional site of cancer compared to HER2+/ER+ patients (42% vs 23%). Conversely, among HER2- patients, rates of additional ipsilateral cancer were similar for HER2-/ER+ (26%) and HERr2-/ER- (23%) patients. Of the 216 patients (HER2+ and HER2-) with additional ipsilateral MRI findings (benign or malignant), 125/216 (58%) patients were deemed appropriate breast conservation (BCT) candidates after MRI. However, BCT was only chosen in 84/125 (67%) patients. Additional contralateral disease was documented in 8% of HER2+ versus 5% of HER2- patients.
 Conclusions: HER2 positivity remains and important prognostic factor for women with breast cancer. Indications for routine preoperative MRI are unclear. In patients with newly diagnosed Her2+ invasive breast cancer routine preoperative MRI may be valuable in the subset of patients who are also ER-. Further study is needed to determine the influence of MRI on patient decisions for surgical therapy. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4020.

Abstract Abstract #4018 Background: Preoperative breast magnetic resonance imaging (MRI) has been shown to identify occult breast disease in women with newly diagnosed breast cancer. We sought to determine the accuracy of MRI in predicting the actual pathologic tumor size in women with newly diagnosed breast cancer.
 Methods: Preoperative breast MRI was reviewed in 460 women with newly diagnosed breast cancer. The size in terms of maximum tumor dimension, of 476 incident breast cancers on MRI were recorded and correlated with the actual pathologic size upon surgical resection. The correlation of size from MRI to pathology was determined. The size discrepancy was analyzed in relation to tumor size and histology.
 Results: MRI demonstrated 476 breast cancers (460 in the ipsilateral breast and 16 with concurrent contralateral breast cancer). Median age was 62 with a range of 25 to 91. The T stages of the population included T0 in 19% of the women, 60% had T1 lesions, 18% had T2 lesions and 3% were T3 or T4. The histology consisted of DCIS alone in 20%, infiltrating ductal in 74% and infiltrating lobular in 6%. Pre-operative MRI was unable to define an enhancing lesion usually due to hematoma following core needle biopsy in 9.8% (47/476). MRI described the size of the incident lesion in 90% (429/476). The mean difference in size between the preoperative MRI and the actual pathologic size for the entire group was 2.4 mm. MRI underestimated tumor size in only 3% of cases. The mean difference according to T stage and histology between MRI and actual pathologic size is listed in Table 1. The percentage of difference between MRI size and pathologic size for the entire group is presented in Table 2.
 
 
 
 Discussion: The mean difference in tumor size estimated by preoperative MRI in women with newly diagnosed breast cancer was within 5 mm of the actual pathologic size in 68% of patients. MRI was accurate in predicting T stage with no significant difference in relation to histology or T stage. This analysis further clarifies the role of preoperative MRI in surgical and treatment planning. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4018.

Abstract Abstract #4014 Background
 Preoperative magnetic resonance imaging (MRI) of the breasts in women with breast cancer (BC) has improved the detection of occult ipsilateral (I/L) and contralateral (C/L) malignancies. Breast MRI findings in patients with estrogen receptor (ER), progesterone receptor (PR), and HER2 negative (triple negative (TN)) disease have not been previously reported. Women with TN BC are at increased risk of distant metastases and a reduced survival vs. BC patients as a whole. One potential explanation may be the presence of occult disease. The role of bilateral breast MRI in these patients remains to be determined.
 Hypothesis
 Patients with TN BC are more likely to have occult malignancy identified by preoperative MRI vs. those with non-TN BC.
 Methods
 All newly diagnosed BC patients from 2003-2007 were reviewed. Information on age, race, histology, ER, PR, HER2, staging, treatment, MRI findings, subsequent investigations, and additional cancer diagnoses was recorded. The incidence of additional I/L or C/L malignany was calculated. The percentage of total patients initially felt to be candidates for partial breast irradiation who required a change in their cancer management was calculated.
 Results
 55 (11%) were diagnosed with TN BC, of whom 52 women completed preoperative MRI. 456 (89%) had non-TN BC; 421 completed preoperative MRI. The median age among TN and non-TN patients was 62 years (Table 1). A majority of women in both groups were Caucasian. African-American women were more likely to be diagnosed with TN vs. non-TN disease (11% vs. 6%).
 
 I/L BC was documented in 13/52 (25%) of TN patients vs. 25% of non-TN patients. No C/L cancers were detected in the TN group (6% in the non-TN group). Of the TN group, 15 patients required a change in their treatment (29%) based on findings from MRI vs. 32% of non-TN patients.
 Conclusions
 Patients with a new diagnosis of TN BC are not at increased risk of occult malignancy than those with non-TN BC. 25% of patients with TN BC had additional I/L disease not previously detected on clinical examination, mammogram, or ultrasound. Of those with non-TN BC, 25% were diagnosed with an additional I/L and 6% with C/L malignancy. The benefit of MRI was limited by false positives, with a number of patients in both groups undergoing a benign biopsy.
 These results suggest that patients with TN BC are not more likely than those with non-TN disease to have additional occult I/L or C/L cancer. The incidence of additional disease remains high and preoperative MRI may be beneficial. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4014.

Abstract Long-term outcomes and hence the role of adjuvant therapy in patients with small (≤1 cm), node-negative breast cancer remain unclear. This study's objective was to evaluate whether human epidermal growth factor receptor (HER)-2 status is an independent, poor prognostic marker in patients with these tumors and to identify a subgroup of patients with these small tumors who might benefit from adjuvant systemic therapy. All patients with a diagnosis of a node-negative breast tumor measuring ≤1 cm and available HER-2 test results between January 1, 2001, and December 31, 2005, at the three Mayo Clinic sites were identified. Clinicopathologic data were compared in three groups: HER-2−, HER-2+, and triple-negative (TN) tumors. Of the 421 tumors identified, 364 (86.5%) were HER-2−, 28 (6.7%) were HER-2+, and 29 (6.9%) were TN. The median follow-up time was 1,015 days (range, 1–2,549 days). Groups were balanced in terms of patient age and tumor histology. Eleven patients with HER-2− tumors (3.0%), seven with HER-2+ tumors (25.0%), and eight with TN tumors (27.6%) received adjuvant chemotherapy. Follow-up data were available for 357, 28, and 28 patients in the three groups, respectively. Death rates in the three groups were 6.4% (23 of 357) (one recurrence-related death), 0% (0 of 28), and 7.1% (2 of 28) (one recurrence-related death), respectively. During follow-up, the tumor recurred in nine patients: four were HER-2− tumors (1.1%), two were HER-2+ tumors (7.1%), and three were TN tumors (10.7%). Patients with small, node-negative breast tumors have an excellent prognosis, but HER-2+ and TN tumors appear to have a higher recurrence rate, warranting consideration for broad use and optimization of systemic adjuvant treatments.

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.

Abstract Background: The International Lung Cancer Consortium was established in 2004. To clarify the role of DNA repair genes in lung cancer susceptibility, we conducted a pooled analysis of genetic variants in DNA repair pathways, whose associations have been investigated by at least 3 individual studies. Methods: Data from 14 studies were pooled for 18 sequence variants in 12 DNA repair genes, including APEX1, OGG1, XRCC1, XRCC2, XRCC3, ERCC1, XPD, XPF, XPG, XPA, MGMT, and TP53. The total number of subjects included in the analysis for each variant ranged from 2,073 to 13,955 subjects. Results: Four of the variants were found to be weakly associated with lung cancer risk with borderline significance: these were XRCC3 T241M [heterozygote odds ratio (OR), 0.89; 95% confidence interval (95% CI), 0.79-0.99 and homozygote OR, 0.84; 95% CI, 0.71-1.00] based on 3,467 cases and 5,021 controls from 8 studies, XPD K751Q (heterozygote OR, 0.99; 95% CI, 0.89-1.10 and homozygote OR, 1.19; 95% CI, 1.02-1.39) based on 6,463 cases and 6,603 controls from 9 studies, and TP53 R72P (heterozygote OR, 1.14; 95% CI, 1.00-1.29 and homozygote OR, 1.20; 95% CI, 1.02-1.42) based on 3,610 cases and 5,293 controls from 6 studies. OGG1 S326C homozygote was suggested to be associated with lung cancer risk in Caucasians (homozygote OR, 1.34; 95% CI, 1.01-1.79) based on 2,569 cases and 4,178 controls from 4 studies but not in Asians. The other 14 variants did not exhibit main effects on lung cancer risk. Discussion: In addition to data pooling, future priorities of International Lung Cancer Consortium include coordinated genotyping and multistage validation for ongoing genome-wide association studies. (Cancer Epidemiol Biomarkers Prev 2008;17(11):3081–9)

Background— Ambrisentan is a propanoic acid–based, A-selective endothelin receptor antagonist for the once-daily treatment of pulmonary arterial hypertension. Methods and Results— Ambrisentan in Pulmonary Arterial Hypertension, Randomized, Double-Blind, Placebo-Controlled, Multicenter, Efficacy Study 1 and 2 (ARIES-1 and ARIES-2) were concurrent, double-blind, placebo-controlled studies that randomized 202 and 192 patients with pulmonary arterial hypertension, respectively, to placebo or ambrisentan (ARIES-1, 5 or 10 mg; ARIES-2, 2.5 or 5 mg) orally once daily for 12 weeks. The primary end point for each study was change in 6-minute walk distance from baseline to week 12. Clinical worsening, World Health Organization functional class, Short Form-36 Health Survey score, Borg dyspnea score, and B-type natriuretic peptide plasma concentrations also were assessed. In addition, a long-term extension study was performed. The 6-minute walk distance increased in all ambrisentan groups; mean placebo-corrected treatment effects were 31 m ( P =0.008) and 51 m ( P <0.001) in ARIES-1 for 5 and 10 mg ambrisentan, respectively, and 32 m ( P =0.022) and 59 m ( P <0.001) in ARIES-2 for 2.5 and 5 mg ambrisentan, respectively. Improvements in time to clinical worsening (ARIES-2), World Health Organization functional class (ARIES-1), Short Form-36 score (ARIES-2), Borg dyspnea score (both studies), and B-type natriuretic peptide (both studies) were observed. No patient treated with ambrisentan developed aminotransferase concentrations >3 times the upper limit of normal. In 280 patients completing 48 weeks of treatment with ambrisentan monotherapy, the improvement from baseline in 6-minute walk at 48 weeks was 39 m. Conclusions— Ambrisentan improves exercise capacity in patients with pulmonary arterial hypertension. Improvements were observed for several secondary end points in each of the studies, although statistical significance was more variable. Ambrisentan is well tolerated and is associated with a low risk of aminotransferase abnormalities.

Alterations in cerebrovascular regulation related to vascular oxidative stress have been implicated in the mechanisms of Alzheimer's disease (AD), but their role in the amyloid deposition and cognitive impairment associated with AD remains unclear. We used mice overexpressing the Swedish mutation of the amyloid precursor protein (Tg2576) as a model of AD to examine the role of reactive oxygen species produced by NADPH oxidase in the cerebrovascular alterations, amyloid deposition, and behavioral deficits observed in these mice. We found that 12- to 15-month-old Tg2576 mice lacking the catalytic subunit Nox2 of NADPH oxidase do not develop oxidative stress, cerebrovascular dysfunction, or behavioral deficits. These improvements occurred without reductions in brain amyloid-β peptide (Aβ) levels or amyloid plaques. The findings unveil a previously unrecognized role of Nox2-derived radicals in the behavioral deficits of Tg2576 mice and provide a link between the neurovascular dysfunction and cognitive decline associated with amyloid pathology.