E. Claire Dees

The Triple Negative Paradox: Primary Tumor Chemosensitivity of Breast Cancer Subtypes

Purpose: Gene expression analysis identifies several breast cancer subtypes. We examined the relationship of neoadjuvant chemotherapy response to outcome among these breast cancer subtypes. Experimental Design: We used immunohistochemical profiles [human epidermal growth factor receptor 2–positive (HER2+)/hormone receptor–negative for HER2+/estrogen receptor–negative (ER−), hormone receptor and HER2− for basal-like, hormone receptor–positive for luminal] to subtype a prospectively maintained data set of patients with breast cancer treated with neoadjuvant anthracycline-based (doxorubicin plus cyclophosphamide, AC) chemotherapy. We analyzed each subtype for clinical and pathologic response to neoadjuvant chemotherapy and examined the relationship of response to distant disease–free survival and overall survival. Results: Of the 107 patients tested, 34 (32%) were basal-like, 11 (10%) were HER2+/ER−, and 62 (58%) were luminal. After neoadjuvant AC, 75% received subsequent chemotherapy and all received endocrine therapy if hormone receptor–positive. The chemotherapy regimen and pretreatment stage did not differ by subtype. Clinical response to AC was higher among the HER2+/ER− (70%) and basal-like (85%) than the luminal subtypes (47%; P < 0.0001). Pathologic complete response occurred in 36% of HER2+/ER−, 27% of basal-like, and 7% of luminal subtypes (P = 0.01). Despite initial chemosensitivity, patients with the basal-like and HER2+/ER− subtypes had worse distant disease–free survival (P = 0.04) and overall survival (P = 0.02) than those with the luminal subtypes. Regardless of subtype, only 2 of 17 patients with pathologic complete response relapsed. The worse outcome among basal-like and HER+/ER− subtypes was due to higher relapse among those with residual disease (P = 0.003). Conclusions: Basal-like and HER2+/ER− subtypes are more sensitive to anthracycline-based neoadjuvant chemotherapy than luminal breast cancers. Patients that had pathologic complete response to chemotherapy had a good prognosis regardless of subtype. The poorer prognosis of basal-like and HER2+/ER− breast cancers could be explained by a higher likelihood of relapse in those patients in whom pathologic complete response was not achieved.

Phase I Safety, Pharmacokinetics, and Clinical Activity Study of Lapatinib (GW572016), a Reversible Dual Inhibitor of Epidermal Growth Factor Receptor Tyrosine Kinases, in Heavily Pretreated Patients With Metastatic Carcinomas

PURPOSE This study (EGF10004) assessed the safety/tolerability, pharmacokinetics, and clinical activity of daily oral dosing with lapatinib (GW572016) in patients with ErbB1-expressing and/or ErbB2-overexpressing advanced-stage refractory solid tumors. PATIENTS AND METHODS Heavily pretreated patients with ErbB1-expressing and/or ErbB2-overexpressing metastatic cancers were randomly assigned to one of five dose cohorts of lapatinib administered once daily. Pharmacokinetic samples were obtained on days 1 and 20. Clinical response was assessed every 8 weeks. RESULTS Sixty-seven patients with metastatic solid tumors were treated with lapatinib. The most frequently reported drug-related adverse events were diarrhea (42%) and rash (31%). No grade 4 drug-related adverse events were reported. Five grade 3 drug-related toxicities (gastrointestinal events and rash) were experienced by four patients. Drug-related interstitial pneumonitis or cardiac dysfunction associated with other ErbB-targeted therapies was not reported. Four patients with trastuzumab-resistant metastatic breast cancer-two of whom were classified as having inflammatory breast cancer-had partial responses (PRs). Twenty-four patients with various other carcinomas experienced stable disease, of whom 10 received lapatinib for > or = 6 months. The relationships between lapatinib dose or serum concentration and clinical response could not be adequately characterized due to the limited response data. The incidence of diarrhea increased with increasing dose, whereas the incidence of rash was not related to dose. CONCLUSION Lapatinib was well tolerated at doses ranging from 500 to 1,600 mg once daily. Clinical activity was observed in heavily pretreated patients with ErbB1-expressing and/or ErbB2-overexpressing metastatic cancers, including four PRs in patients with trastuzumab-resistant breast cancers and prolonged stable disease in 10 patients.

Study of the Biologic Effects of Lapatinib, a Reversible Inhibitor of ErbB1 and ErbB2 Tyrosine Kinases, on Tumor Growth and Survival Pathways in Patients With Advanced Malignancies

PURPOSE This was a pilot study to assess the biologic effects of lapatinib on various tumor growth/survival pathways in patients with advanced ErbB1 and/or ErbB2-overexpressing solid malignancies. PATIENTS AND METHODS Heavily pretreated patients with metastatic cancers overexpressing ErbB2 and/or expressing ErbB1 were randomly assigned to one of five dose cohorts of lapatinib (GW572016) administered orally once daily continuously. The biologic effects of lapatinib on tumor growth and survival pathways were assessed in tumor biopsies obtained before and after 21 days of therapy. Clinical response was determined at 8 weeks. RESULTS Sequential tumor biopsies from 33 patients were examined. Partial responses occurred in four patients with breast cancer, and disease stabilization occurred in 11 others with various malignancies. Responders exhibited variable levels of inhibition of p-ErbB1, p-ErbB2, p-Erk1/2, p-Akt, cyclin D1, and transforming growth factor alpha. Even some nonresponders demonstrated varying degrees of biomarker inhibition. Increased tumor cell apoptosis (TUNEL) occurred in patients with evidence of tumor regression but not in nonresponders (progressive disease). Clinical response was associated with a pretreatment TUNEL score > 0 and increased pretreatment expression of ErbB2, p-ErbB2, Erk1/2, p-Erk1/2, insulin-like growth factor receptor-1, p70 S6 kinase, and transforming growth factor alpha compared with nonresponders. CONCLUSION Lapatinib exhibited preliminary evidence of biologic and clinical activity in ErbB1 and/or ErbB2-overexpressing tumors. However, the limited sample size of this study and the variability of the biologic endpoints suggest that further work is needed to prioritize biomarkers for disease-directed studies, and underscores the need for improved trial design strategies in early clinical studies of targeted agents.

Phase I and Pharmacokinetic Study of Sorafenib in Patients With Hepatic or Renal Dysfunction: CALGB 60301

PURPOSE We sought to characterize the pharmacokinetics (PK) and determine a tolerable dose of oral sorafenib in patients with hepatic or renal dysfunction. PATIENTS AND METHODS Patients were assigned to one of nine cohorts: cohort 1, bilirubin < or = upper limit of normal (ULN) and AST < or = ULN and creatinine clearance (CC) > or = 60 mL/min; cohort 2, bilirubin more than ULN but < or = 1.5x ULN and/or AST more than ULN; cohort 3, CC between 40 and 59 mL/min; cohort 4, bilirubin more than 1.5x ULN to < or = 3x ULN (any AST); cohort 5, CC between 20 and 39 mL/min; cohort 6, bilirubin more than 3x ULN to 10x ULN (any AST); cohort 7, CC less than 20 mL/min; cohort 8, albumin less than 2.5 mg/dL (any bilirubin/AST); and cohort 9, hemodialysis. Sorafenib was administered as a 400-mg dose on day 1 for PK, and continuous daily dosing started on day 8. RESULTS Of 150 registered patients, 138 patients were treated. With the exception of cohorts 6 and 7, at least 12 patients per cohort were assessable, and the dose level with prospectively defined dose-limiting toxicity in less than one third of patients by day 29 was considered tolerable. No significant associations between the sorafenib PK and cohort were found. CONCLUSION We recommend the following empiric sorafenib starting doses by cohort: cohort 1, 400 mg twice a day; cohort 2, 400 mg twice a day; cohort 3, 400 mg twice a day; cohort 4, 200 mg twice a day; cohort 5, 200 mg twice a day; cohort 6, not even 200 mg every third day tolerable; cohort 7, not defined; cohort 8, 200 mg each day; and cohort 9, 200 mg each day.

The interaction of post-traumatic growth and post- traumatic stress symptoms in predicting depressive symptoms and quality of life

Objective: We sought to explore whether post‐traumatic growth (PTG) (positive change or benefit finding resulting from trauma) moderates relationships between post‐traumatic stress symptoms (PTSS) and both depression and quality of life (QOL) among breast cancer survivors.

Genotype-Guided Tamoxifen Dosing Increases Active Metabolite Exposure in Women With Reduced CYP2D6 Metabolism: A Multicenter Study

PURPOSE We examined the feasibility of using CYP2D6 genotyping to determine optimal tamoxifen dose and investigated whether the key active tamoxifen metabolite, endoxifen, could be increased by genotype-guided tamoxifen dosing in patients with intermediate CYP2D6 metabolism. PATIENTS AND METHODS One hundred nineteen patients on tamoxifen 20 mg daily ≥ 4 months and not on any strong CYP2D6 inhibiting medications were assayed for CYP2D6 genotype and plasma tamoxifen metabolite concentrations. Patients found to be CYP2D6 extensive metabolizers (EM) remained on 20 mg and those found to be intermediate (IM) or poor (PM) metabolizers were increased to 40 mg daily. Eighty-nine evaluable patients had tamoxifen metabolite measurements repeated 4 months later. RESULTS As expected, the median baseline endoxifen concentration was higher in EM (34.3 ng/mL) compared with either IM (18.5 ng/mL; P = .0045) or PM (4.2 ng/mL; P < .001). When the dose was increased from 20 mg to 40 mg in IM and PM patients, the endoxifen concentration rose significantly; in IM there was a median intrapatient change from baseline of +7.6 ng/mL (-0.6 to 23.9; P < .001), and in PM there was a change of +6.1 ng/mL (2.6 to 12.5; P = .020). After the dose increase, there was no longer a significant difference in endoxifen concentrations between EM and IM patients (P = .84); however, the PM endoxifen concentration was still significantly lower. CONCLUSION This study demonstrates the feasibility of genotype-driven tamoxifen dosing and demonstrates that doubling the tamoxifen dose can increase endoxifen concentrations in IM and PM patients.

Risk Perceptions and Psychosocial Outcomes of Women With Ductal Carcinoma In Situ: Longitudinal Results From a Cohort Study

BACKGROUND Ductal carcinoma in situ (DCIS) has a generally favorable overall prognosis, with a systemic recurrence rate of approximately 1%, a local recurrence rate after mastectomy of 1%, and a local recurrence rate after breast-conserving treatment of less than 10%. Preliminary studies have suggested that women with DCIS may overestimate their risk of disease recurrence. Few data exist regarding psychosocial outcomes for women with DCIS. METHODS Women in Eastern Massachusetts with newly diagnosed DCIS were asked to participate in a longitudinal study of risk perceptions, psychosocial concerns, and health behaviors. Psychosocial outcomes after DCIS diagnosis and risk perceptions were evaluated at enrollment and at 9 and 18 months. All statistical tests were two-sided. RESULTS Four hundred eighty-seven women with DCIS (64% of eligible participants) completed the enrollment survey. Overall quality of life was good among the women surveyed, and the substantial anxiety at enrollment decreased with time (P < .001). At enrollment, 54% perceived at least a moderate risk for DCIS recurrence in the next 5 years, 68% in their lifetime; 39% perceived at least a moderate risk for invasive cancer in the next 5 years, 53% in their lifetime; and 28% perceived at least a moderate likelihood of DCIS spreading to other places in their body. At 18 months after enrollment, perceived risks had not statistically significantly changed from those at enrollment (P = .38). Anxiety at enrollment was the factor that was most consistently and strongly associated with overestimation of future breast cancer-related risks (perceived moderate or greater risk vs less than moderate risk of DCIS recurring within 5 years: odds ratio [OR] = 4.0, 95% confidence interval [CI] = 1.6 to 9.9, P = .003; of invasive breast cancer within 5 years: OR = 4.3, 95% CI = 1.9 to 9.9, P < .001; and of invasive breast cancer during lifetime: OR = 5.3, 95% CI = 2.0 to 14.3, P < .001). CONCLUSIONS Many women with newly diagnosed DCIS have inaccurate perceptions of the breast cancer risks that they face, and anxiety is particularly associated with these inaccurate perceptions.

The role of the ubiquitination-proteasome pathway in breast cancer: Applying drugs that affect the ubiquitin-proteasome pathway to the therapy of breast cancer

The ubiquitin-proteasome pathway is responsible for most eukaryotic intracellular protein degradation. This pathway has been validated as a target for antineoplastic therapy using both in vitro and preclinical models of human malignancies, and is influenced as part of the mechanism of action of certain chemotherapeutic agents. Drugs whose primary action involves modulation of ubiquitin-proteasome activity, most notably the proteasome inhibitor PS-341, are currently being evaluated in clinical trials, and have already been found to have significant antitumor efficacy. On the basis of the known mechanisms by which these agents work, and the available clinical data, they would seem to be well suited for the treatment of breast neoplasms. Such drugs, alone and especially in combination with current chemotherapeutics, may well represent important advances in the therapy of patients with breast cancer.

Phase I Dose-Escalation Study of LCL161, an Oral Inhibitor of Apoptosis Proteins Inhibitor, in Patients With Advanced Solid Tumors

PURPOSE LCL161 antagonizes the function of inhibitor of apoptosis proteins (IAPs), thereby promoting cancer cell death. This first-in-human dose-escalation study assessed the maximum-tolerated dose (MTD), safety, pharmacokinetics, and pharmacodynamics of LCL161 in patients with advanced solid tumors. A second part of the study assessed the relative bioavailability of a tablet versus solution formulation. PATIENTS AND METHODS LCL161 was administered orally, once weekly, on a 21-day cycle to adult patients with advanced solid tumors by using an adaptive Bayesian logistic regression model with overdose control-guided dose escalation. RESULTS Fifty-three patients received at least one dose of LCL161 (dose range, 10 to 3,000 mg). LCL161 was well tolerated at doses up to 1,800 mg. Cytokine release syndrome (CRS) was the only dose-limiting toxicity (in three [6%] of 53 patients) and was the most common grades 3 to 4 event (in five [9%] of 53 patients). Vomiting, nausea, asthenia/fatigue, and anorexia were common but not severe. Although the MTD was not formally determined, an 1,800-mg dose was selected in compliance with the protocol for additional study, given the dose-limiting CRS at higher doses and pharmacodynamic activity at lower doses. LCL161 was rapidly absorbed, and exposure was generally increased with dose. The tablet formulation of LCL161 was better tolerated than the solution; tablet and solution formulations had similar exposures, and the solution was discontinued. No patient had an objective response. LCL161 induced degradation of cellular IAP1 protein in the blood, skin, and tumor and increased circulating cytokine levels. CONCLUSION The 1,800-mg dose of LCL161, administered as a single agent once weekly, in tablet formulation is the recommended dose for additional study. This combined dose and formulation was well tolerated and had significant pharmacodynamic activity, which warrants additional investigation.

Retention and use of breast cancer recurrence risk information from genomic tests : The role of health literacy

Background: New genomic technology now allows physicians to provide women with individualized and highly accurate breast cancer recurrence risk estimates that are a key factor in adjuvant (after surgery) therapy decisions. Because these genomic tests are so new, little is known about how well patients understand the tests and their results. Method: We interviewed 163 stage I or II breast cancer patients at a routine follow-up appointment. We assessed their health literacy (using the Rapid Estimate of Adult Learning in Medicine) as well as their knowledge of and attitudes towards a genomic test that identifies risk of recurrence in hormone receptor–positive, node–negative breast cancer (the OncoType Dx Recurrence Score). Results: Women with lower health literacy recalled less of the information provided about the recurrence risk test than women with higher health literacy. Health literacy was not related to the amount of additional information women desired. Women with higher health literacy preferred to have a more active role in decisions about the test. Implications: Health literacy may affect womens capacity to learn about the new genomic tests as well as their desire for informed participation in their medical care. (Cancer Epidemiol Biomarkers Prev 2007;16(2):249–55)