Targeting Estrogen Receptor Beta in a Phase 2 Study of High-Dose Estradiol in Metastatic Triple-Negative Breast Cancer: A Wisconsin Oncology Network Study.

BACKGROUND: Estrogen receptor beta (ERß) is expressed by 50% to 80% of triple-negative breast cancers (TNBC). Agonism of ERß has antiproliferative effects in TNBC cells expressing ERß. This phase 2 study evaluated single-agent high-dose estradiol in patients with advanced TNBC. PATIENTS AND METHODS: Adult women with measurable advanced TNBC were treated with estradiol 10 mg oral 3 times daily provided continuously for 28-day cycles. A Simon optimal 2-stage design was used. The primary end point was objective response (OR). Secondary end points included progression-free survival (PFS), clinical benefit (CB), and safety. OR, CB, and PFS by ERß status were also examined. RESULTS: Seventeen evaluable women were enrolled. Median age was 58 years (range, 34-90 years); the median number of prior systemic therapies was 2 (range, 0-6). One patient had a confirmed partial response (OR rate, 5.9%) and remained on the study for > 24 weeks. Three patients had stable disease, with one lasting more than 16 weeks. ERß expression was detected in 77% (13 patients). The CB rate at 16 weeks was 15% (2 of 13) in ERß-positive patients and 0% (0 of 4) in ERß-negative patients (P = 1). PFS was poor (median, 1.9 months) and not statistically significantly different between ERß-positive versus -negative patients. No new adverse events from estradiol were identified. The study closed after the first stage as a result of limited responses in these unselected patients. CONCLUSION: In unselected TNBC, high-dose estradiol has limited efficacy. However, further evaluation of ERß selective agonists in TNBC selected by ERß expression may be warranted.

Acetyl-L-carnitine (ALCAR) for the prevention of chemotherapy-induced peripheral neuropathy in patients with relapsed or refractory multiple myeloma treated with bortezomib, doxorubicin and low-dose dexamethasone: a study from the Wisconsin Oncology Network.

PURPOSE: Retreatment with bortezomib (B) is often considered for patients with relapsed multiple myeloma (MM), but this strategy is hindered by uncertainty of response and emergence of B-induced peripheral neuropathy (PN). We incorporated acetyl-L-carnitine (ALCAR) to prevent PN and allow for adequate dosing. We also investigated the correlation between B-inducible NF-κB activation and response to therapy. METHODS: Nineteen patients with relapsed/refractory MM received up to 8 cycles of intravenous bortezomib, doxorubicin and oral low-dose dexamethasone (BDD) to evaluate response and toxicity. Thirteen additional patients received prophylactic ALCAR (BDD-A). Patients receiving BDD-A were evaluated by FACT-GOG-TX, FACIT-Fatigue, Neuropathic Pain index (NPI) and Grooved Pegboard (GP) testing. Primary MM cells from 11 patients were tested for B-inducible NF-κB activation. RESULTS: Seventy-six percent of subjects were refractory to previous treatment, 39% refractory to bortezomib. Median cycles received were 5. CR + PR for the entire group were 53% and did not differ between groups. Incidence of ≥3 PN was 32% in the BDD group versus 15 % in the BDD-A group (p = ns). Patient-reported fatigue and PN measured by FACT-GOG-TX increased throughout the treatment period in the BDD-A group, although time to complete GP testing declined. In a sub-study examining constitutive bortezomib-inducible NF-κB activity in primary subject-specific MM cells, the presence of NF-κB activation correlated with lower likelihood of response. CONCLUSIONS: Addition of ALCAR to BDD did not alter the incidence or severity of PN in relapsed MM patients receiving a B-based regimen. Bortezomib-inducible NF-κB activation in patient-derived primary MM cells may be associated with poorer response.

Feasibility of 4 cycles of docetaxel and cyclophosphamide every 14 days as an adjuvant regimen for breast cancer: a Wisconsin Oncology Network study.

INTRODUCTION: Dose-dense therapies have had a major effect on reducing toxicity and improving outcomes in breast cancer. A combination of TC every 3 weeks has emerged as a common chemotherapy regimen used for treatment of node-negative or lower-risk node-positive breast cancer. We tested whether it is feasible to deliver TC on a dose-dense schedule, with therapy completed within 10 weeks. PATIENTS AND METHODS: We enrolled women with early stage breast cancer on a single-arm phase II study of adjuvant dose-dense TC through a regional oncology network. All women completed primary surgery before accrual, and subsequent therapy with TC was deemed appropriate by the treating physician. Planned treatment was docetaxel 75 mg/m(2) plus cyclophosphamide 600 mg/m(2) every 2 weeks for 4 cycles with subcutaneous pegfilgrastim 6 mg administered 24 to 48 hours after the administration of each chemotherapy cycle. RESULTS: Of 42 women enrolled, 41 were evaluable using prespecified criteria. Of these, 37 (90.2%) completed therapy within 10 weeks and 34 (83%) completed therapy at 8 weeks without dose modification. Rates of neuropathy were similar to that reported previously. The rate of neutropenic fever was low (2.5%). Rash and plantar-palmar erythrodythesia were common and reached grade 3 in 4 subjects (9.8%). CONCLUSION: Dose-dense TC is feasible with tolerability profiles similar to standard TC and a low likelihood of neutropenic fever. This study supports further clinical development of this 8-week adjuvant chemotherapy regimen.

Newer therapies in advanced prostate cancer.

Prostate cancer is a leading cause of morbidity and mortality among males. Androgen ablation as initial therapy for advanced prostate cancer provides high response rates but does not cure disease, as nearly all men with metastases will eventually progress to hormone-refractory prostate cancer (HRPC). Present chemotherapy regimens for HRPC can provide palliation and have recently demonstrated an increase in overall survival. Over the past 2 decades, these regimens represent clear advances in the treatment of metastatic prostate cancer but also demonstrate that newer therapies are needed. Studies are ongoing to provide viable alternatives among traditional cytotoxic therapies as well as among novel agents targeting specific molecular pathways. This article reviews some of the newer therapies being developed and evaluated, including the epothilone analogues, human epidermal growth factor receptor pathway inhibitors, angiogenesis inhibitors, and endothelin receptor antagonists.