Abstract P5-19-02: Methodological approaches to the use of real-world data(RWD) for medical products to treat breast cancer: An FDA oncology center of excellence evaluation of RWD submissions

Background: Aligning with 21st Century Cures legislation, FDA is exploring various methodologies to advance appropriate uses of Real-World Data (RWD) to generate Real-World Evidence (RWE). Inclusion of RWD to support regulatory decision making has increased in oncology, and this review specifically focused on characterizing RWD submissions for the treatment of breast cancer (BC). Methods: A systematic search was conducted using internal FDA databases to identify RWD submissions from 2010 to 2020. Search terms included real world evidence, real world data, cancer registry, administrative claims, external control arm, and other terms relevant to RWD/RWE. Relevant regulatory submissions were reviewed, pre-defined common data elements were extracted, and the subset applicable to breast cancer was evaluated. Results: Of 142 regulatory submissions that included RWD, 6 specifically evaluated BC indications and 3 were for solid tumor indications with potential applicability to BC, corresponding to 4 new molecular entities. Regulatory objectives included support for labeling changes including efficacy (expanded indications), safety , and dose or administration modifications. The most commonly used design was a retrospective observational study with structured electronic health records (EHRs) or medical claims data, supplemented by unstructured data from medical records or chart review for missing data elements. Four of the 6 BC submissions were significantly limited by a high degree of data missingness and confounding, with some studies including key covariates that were missing in >50% of the structured data. RWD was used to provide contextual evidence for label expansion for populations not included or adequately represented in the registration trial. Of note, for the application expanding the label to include treatment of male BC, the regulatory decision was primarily based on clinical trial data. The primary rwEndpoints submitted were overall survival (rwOS), progression free survival (rwPFS), response rate (rwORR) and time to next treatment (TTNT). Safety outcomes were investigated in all but 1 of the studies, most commonly as a secondary RWD endpoint. Conclusion: In our review of regulatory submissions relevant to breast cancer therapies, RWD has largely been used to contextualize and complement prospective clinical trial data. Evaluating that selected RWD is fit for purpose to address the regulatory objective(s) and all analytical plans are prespecified allows for robust data characterization, and appropriate evaluation. Data relevance (availability of key variables) along with reliability assessment which includes evaluating data for completeness, consistency, and trends over time are necessary for the rigorous evaluation of RWE in drug development. Data missingness is a key issue in RWD, especially when structured data are not available and specific variables are unlikely to be captured in a reliable way in the unstructured data or further validation is not feasible. To optimize RWD as evidence for specific patient populations, attention to the proportion of patients excluded is necessary to avoid concerns regarding the generalizability of the data. Careful selection of rwEndpoints must be aligned with the study design and objective, include data such as prior, concomitant and subsequent anti-cancer treatments, and the ability for outcome validation to be methodologically appropriate. When contemplating a regulatory submission using RWD, early consultation with the appropriate FDA review division can provide additional feedback on the appropriate use of RWD or pragmatic designs.

Citation Format: Melanie E Royce, Jennifer J. Lee, Christy L. Osgood, Laleh Amiri-Kordestani, Julia A. Beaver, Paul G. Kluetz, Donna R. Rivera. Methodological approaches to the use of real-world data(RWD) for medical products to treat breast cancer: An FDA oncology center of excellence evaluation of RWD submissions [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P5-19-02.

E2112: Randomized Phase III Trial of Endocrine Therapy Plus Entinostat or Placebo in Hormone Receptor-Positive Advanced Breast Cancer. A Trial of the ECOG-ACRIN Cancer Research Group

PURPOSE

Endocrine therapy resistance in advanced breast cancer remains a significant clinical problem that may be overcome with the use of histone deacetylase inhibitors such as entinostat. The ENCORE301 phase II study reported improvement in progression-free survival (PFS) and overall survival (OS) with the addition of entinostat to the steroidal aromatase inhibitor (AI) exemestane in advanced hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancer.

PATIENTS AND METHODS

E2112 is a multicenter, randomized, double-blind, placebo-controlled phase III study that enrolled men or women with advanced HR-positive, HER2-negative breast cancer whose disease progressed after nonsteroidal AI. Participants were randomly assigned to exemestane 25 mg by mouth once daily and entinostat (EE) or placebo (EP) 5 mg by mouth once weekly. Primary end points were PFS by central review and OS. Secondary end points included safety, objective response rate, and lysine acetylation change in peripheral blood mononuclear cells between baseline and cycle 1 day 15.

RESULTS

Six hundred eight patients were randomly assigned during March 2014-October 2018. Median age was 63 years (range 29-91), 60% had visceral disease, and 84% had progressed after nonsteroidal AI in metastatic setting. Previous treatments included chemotherapy (60%), fulvestrant (30%), and cyclin-dependent kinase inhibitor (35%). Most common grade 3 and 4 adverse events in the EE arm included neutropenia (20%), hypophosphatemia (14%), anemia (8%), leukopenia (6%), fatigue (4%), diarrhea (4%), and thrombocytopenia (3%). Median PFS was 3.3 months (EE) versus 3.1 months (EP; hazard ratio = 0.87; 95% CI, 0.67 to 1.13; P = .30). Median OS was 23.4 months (EE) versus 21.7 months (EP; hazard ratio = 0.99; 95% CI, 0.82 to 1.21; P = .94). Objective response rate was 5.8% (EE) and 5.6% (EP). Pharmacodynamic analysis confirmed target inhibition in entinostat-treated patients.

CONCLUSION

The combination of exemestane and entinostat did not improve survival in AI-resistant advanced HR-positive, HER2-negative breast cancer.

FDA Oncology Center of Excellence landscape analysis of real-world data submissions for oncology drugs

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Background: Aligning with 21st Century Cures legislation, the FDA is exploring trial design modernization and methodology to advance appropriate uses of Real World Data (RWD) to generate Real World Evidence (RWE). The Oncology Center of Excellence RWE Program was established in 2020 to advance RWE efforts specific to oncology drug development. Inclusion of RWD to support regulatory decision making has increased in oncology, and a landscape analysis was conducted to characterize the RWD included in submissions. Methods: A systematic search was conducted using internal FDA databases to identify RWD submissions from 2010 to 2020. Search terms included: real world evidence, real world data, electronic health record, cancer registry, administrative claims, external control arm, observational cohort, historical control arm, rwOS, rwRR, rwCR, and rwORR. Relevant regulatory submissions were reviewed, and pre-defined common data elements were extracted. A team of FDA reviewers assessed agreement through subset validation (20%). Descriptive statistics were calculated. Results: A total of 142 regulatory submissions included RWD from 2011 to 2020. A subset of 94 submissions met the criteria for evaluation, consisting of 78 unique studies evaluating 56 molecular entities. RWD submissions increased substantially over time, with 28 submissions in 2020. Nearly half of the RWD submissions were for solid tumor indications (68%), with lung cancer being the most predominant site. More than one third of the RWD submissions (37%) were for rare indications. The most common primary RWD study objective was effectiveness (62%) and the most commonly referenced RWD source was EHR/clinical data (54%). The most frequently used primary RWD endpoints were survival (rwOS, 35%) and response (rwORR/PR/BTR, 31%) outcomes (Table). Conclusions: Our review demonstrates a dramatic increase in RWD submissions to support FDA oncology drug development programs. Submissions included a variety of study objectives, data sources, and endpoints. While this landscape analysis provides a picture of potential regulatory objectives, the adequacy of each proposal to support regulatory decision making was not evaluated. Establishing a set of clear regulatory objectives can help advance the development of metrics for robust data characterization and outcome validation to ensure that RWD can be appropriately evaluated and provide the rigor necessary to be considered adequate RWE.[Table: see text]

Overall survival in patients with breast cancer treated with a CDK 4/6 inhibitor plus fulvestrant: A U.S. Food and Drug Administration pooled analysis

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JJG, JC, TMP contributed equally. JAB, LAK contributed equally. Background: Cyclin dependent kinase 4/6 inhibitors (CDKIs) are oral targeted agents approved for use in combination with endocrine therapy as first or secondline treatment of hormone-receptor positive (HR+), human epidermal growth factor receptor 2 (HER2)-negative advanced or metastatic breast cancer. We previously reported the pooled analyses of progression-free survival of patients in certain clinicopathologic subgroups, and results showed a consistent benefit from the addition of a CDKI to endocrine therapy. Here, we report the pooled overall survival (OS) results in patients treated with a CDKI plus fulvestrant. Methods: We pooled individual patient data (n=1948) from three phase III randomized breast cancer trials of a CDKI plus fulvestrant submitted to the FDA in support of marketing applications. All analyzed patients received at least one dose of a CDKI or placebo, plus fulvestrant. The median OS was estimated using Kaplan-Meier (KM) methods, and hazard ratios (HR) with corresponding 95% confidence intervals (CIs) were estimated using Cox regression models. Results: Results of OS analyses, including all pooled patients, patients treated in the first-line setting, and patients treated in the second line and later settings, are summarized in the table below. Additional subgroup analyses of OS by progesterone receptor status, site of metastases, breast cancer histology, ECOG performance status, race, and de novo metastatic presentation all favored adding a CDKI to fulvestrant. In patients age < 40, the estimated OS HR favored fulvestrant alone, but this subgroup had a small sample size (n=89), so this result must be interpreted with caution. All results are considered exploratory and hypothesis-generating. Conclusions: Addition of CDKIs to fulvestrant appears to confer a consistent survival benefit across all pooled patients and within most clinicopathological subgroups of interest.[Table: see text]

Abstract GS4-02: E2112: Randomized phase 3 trial of endocrine therapy plus entinostat/placebo in patients with hormone receptor-positive advanced breast cancer. A trial of the ECOG-ACRIN cancer research group

Background: Endocrine therapy resistance in advanced breast cancer remains a significant clinical problem that may be overcome with use of histone deacetylase (HDAC) inhibitors such as entinostat. The ENCORE 301 randomized phase II study reported an improvement in progression-free (PFS) and overall survival (OS) with the addition of entinostat to the steroidal aromatase inhibitor (AI) exemestane in patients with advanced hormone receptor (HR)-positive, HER2-negative breast cancer. Protein lysine acetylation in peripheral blood mononuclear cells (PBMCs) was associated with prolonged PFS in the entinostat arm.

Methods: E2112 is a multicenter randomized double-blind, placebo-controlled phase III study that enrolled men or women with advanced HR-positive, HER2-negative breast cancer whose disease had progressed on a non-steroidal AI in the adjuvant or metastatic setting (NCT02115282). Study participants were also required to have an ECOG performance status 0-1 with measurable or non-measurable (limited to 20% of the study population) disease. One prior chemotherapy for metastatic disease and prior treatment with fulvestrant and a CDK4/6 inhibitor was permitted but not required. Participants received exemestane 25mg po daily and entinostat (EE)/placebo (EP) 5mg po every week. Primary endpoints were PFS (central review) and OS. One-sided type 1 error 0.025 was split between two hypothesis tests: 0.001 for PFS test and 0.024 for OS. PFS tested in the first 360 pts, 88.5% power to detect 42% reduction in the hazard of PFS failure (median PFS, 4.1 to 7.1 months); OS tested in all 600 pts, 80% power to detect 25% reduction in the hazard of death (median OS, 22 to 29.3 months). Secondary endpoints included safety, objective response rate (ORR), and changes in protein lysine acetylation status in PBMCs (CD3+ T cells, CD14+ monocytes, CD19+ B cells, pan-leukocyte marker CD45+ cells, CD56+ NK cells) between C1D1 and C1D15 (integrated biomarker).

Results: A total of 608 participants were randomized between March 2014 and October 2018 (305 EE, 303 EP), 98% enrolled in USA. Characteristics were well balanced between the arms. Median age was 63 years (range, 29-91), 99% female, 95% postmenopausal, 80% white and 15% black. A majority (84%) had disease resistant to AI in the metastatic setting at study entry, 78% had measurable disease and 60% visceral disease. Prior treatments included chemotherapy (60%), fulvestrant (30%), CDK4/6 inhibitor (35%), everolimus (3%). Median prior lines of chemotherapy was 1 (range, 0-4) and endocrine therapy was 2 (range, 1-7); in adjuvant/metastatic setting. Grade 3/4 adverse events in EE arm included neutrophil count decreased (20%), hypophosphatemia (14%), anemia (8%), white blood cell decreased (6%), fatigue (4%), diarrhea (4%), and platelet count decreased (3%). At final analysis, median PFS was 3.3 months (EE) versus 3.1 months (EP) (HR=0.87, 95% CI: 0.67, 1.13, p=0.30). Median OS was 23.4 months (EE) versus 21.7 months (EP) (HR=0.99, 95% CI: 0.82, 1.21, p=0.94). ORR was 4.6% (EE) and 4.3% (EP). The median fold change in lysine acetylation in PBMCs was approximately 1.5 in EE arm, and 1 in EP arm. Participants on EE had significantly higher increase in lysine acetylation by C1D15 than patients on EP (397 paired samples available for analysis, p&lt;0.001 for all). Additional biomarker analyses will be presented at time of meeting.

Conclusion: The combination of exemestane and entinostat did not improve survival in AI resistant advanced HR-positive, HER2-negative breast cancer. Pharmacodynamic analysis confirmed target inhibition in entinostat-treated patients.

Citation Format: Roisin M Connolly, Fengmin Zhao, Kathy D Miller, Min-Jung Lee, Richard L Piekarz, Karen L Smith, Ursa Brown-Glaberman, Jennifer S Winn, Bryan A Faller, Adedayo A Onitilo, Mark E Burkard, George T Budd, Ellis G Levine, Melanie E Royce, Peter A Kaufman, Alexandra Thomas, Jane B Trepel, Antonio C Wolff, Joseph A Sparano. E2112: Randomized phase 3 trial of endocrine therapy plus entinostat/placebo in patients with hormone receptor-positive advanced breast cancer. A trial of the ECOG-ACRIN cancer research group [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr GS4-02.

Disease-Free and Overall Survival Among Patients With Operable HER2-Positive Breast Cancer Treated With Sequential vs Concurrent Chemotherapy: The ACOSOG Z1041 (Alliance) Randomized Clinical Trial

Importance

Pathologic complete response rate (pCR), the primary end point of the ACOSOG (American College of Surgeons Oncology Group) Z1041 (Alliance) trial, and disease-free survival (DFS) and overall survival (OS) in women with operable HER2-positive breast cancer are similar between treatment regimens.

Objective

To assess DFS and OS for patients treated with sequential vs concurrent anthracycline plus trastuzumab.

Design, Setting, and Participants

Phase 3 randomized clinical trial conducted at 36 centers in the continental United States and Puerto Rico. Women 18 years or older with invasive operable HER2-positive breast cancer were enrolled from September 15, 2007, to December 15, 2011, and randomized to 1 of 2 treatment arms. The analysis data set was locked on October 15, 2017, and analysis was completed on December 15, 2017.

Interventions

Patients randomized to arm 1 received 500 mg/m2 of fluorouracil, 75 mg/m2 of epirubicin, and 500 mg/m2 of cyclophosphamide (FEC) every 3 weeks for 12 weeks followed by the combination of 80 mg/m2 of paclitaxel and 2 mg/kg (except initial dose of 4 mg/kg) of trastuzumab weekly for 12 weeks. Patients randomized to arm 2 received the same combination of paclitaxel with trastuzumab weekly for 12 weeks followed by FEC every 3 weeks with weekly trastuzumab for 12 weeks. Women with hormone receptor-positive disease received endocrine therapy, and radiotherapy was delivered at physician discretion.

Main Outcomes and Measures

The primary outcomes were DFS and OS and pCR in the breast and nodes.

Results

Two hundred eighty-two women with HER2-positive breast cancer were enrolled in the trial, and 2 withdrew consent before treatment. Among the remaining 280 women, the median age was 50 years (range, 28-76 years), 232 (82.9%) were white, 29 (10.3%) were black, 8 (2.9%) were Asian, 4 (1.4%) were American Indian or Alaskan Native, and 7 (2.5%) did not report race/ethnicity. There were 22 disease events in arm 1 and 27 in arm 2. Disease-free survival rates did not differ with respect to treatment arm (stratified log-rank P = .96; stratified hazard ratio [HR] [arm 2 to arm 1], 1.02; 95% CI, 0.56-1.83). Overall survival did not differ with respect to treatment arm (stratified log-rank P = .73; stratified HR [arm 2 to arm 1], 1.17; 95% CI, 0.48-2.88).

Conclusions and Relevance

Across a median follow-up of 5.1 years (range, 26 days to 6.2 years), pCR, DFS, and OS did not differ with respect to sequential or concurrent administration of FEC with trastuzumab.

Trial Registration

ClinicalTrials.gov identifier: NCT00513292.

Abstract P5-20-14: Cardiotoxicity in 1 year of treatment with reference trastuzumab and its biosimilar candidate CT-P6 in HER2 positive early stage breast cancer (EBC) patients

Background CT-P6 is a proposed biosimilar to reference trastuzumab. This trial (NCT02162667) evaluated the similarity of CT-P6 and reference trastuzumab for both efficacy and safety in HER2 positive EBC patients. The primary endpoint, pathological complete response (pCR) rate was entirely within the pre-defined equivalence margin (Stebbing et al., Lancet Oncology 2017). Efficacy and safety were similar between the two treatment groups. We aimed to investigate the cardiotoxicity in the 1 year treatment and follow-up period.

Methods A total of 549 patients with HER2 positive EBC were randomized to receive CT-P6 (n=271) or reference trastuzumab (n=278) in combination with docetaxel (Cycles 1-4) and 5-fluorouracil, epirubicin and cyclophosphamide (FEC, Cycles 5-8) in the neoadjuvant setting. CT-P6 or reference trastuzumab was administered at 8 mg/kg (Cycle 1 only) followed by 6 mg/kg every 3 weeks. After surgery, patients received monotherapy of CT-P6 or reference trastuzumab up to 10 cycles in the adjuvant setting. Left ventricular ejection fraction (LVEF) was evaluated by ECHO or MUGA at baseline, every 3 or 4 cycles during treatment and every 6 months thereafter. If LVEF decreased by ≥10 points from baseline and &lt;50%, a reassessment was performed within 3 weeks and the patient was withdrawn from the study treatment if the cardiac toxicity was confirmed.

Results Median follow-up period was 19 months. In total, 96% of patients completed 8 cycles of taxane and anthracycline combination therapy during the neoadjuvant period and 90% of patients in each group received 1-year treatment of CT-P6 or reference trastuzumab.

The relative dose intensity of study drug was similar, indicating good tolerability of CT-P6 and reference trastuzumab (97.5% and 97.3% during the neoadjuvant period; 98.5% and 98.8% during the adjuvant period). Docetaxel and FEC combination therapies were administered approximately 96% of dose intensity in the two groups.

All patients had normal LVEF (≥55%) at baseline. Mean LVEF value was maintained more than 60% during 1-year treatment and follow-up period. Heart failure cases with LVEF decrease (≥10 points from baseline and &lt;50%) were reported to be similar between two groups. Three patients in each group were withdrawn due to LVEF decrease. Adverse events of cardiac disorders were reported to be similar between two groups. All cases were mild or moderate except two cases.

Table 1. Summary of heart failure with LVEF decrease and cardiotoxicity CT-P6 (N=271)Reference Trastuzumab (N=278)LVEF decrease ≥ 10 points and below 50%9 (3.3%)7 (2.5%)- Asymptomatic9 (3.3%)6 (2.1%)- Symptomatic01 (0.4%)- Confirmed2 (0.7%)4 (1.4%)- Withdrawn3 (1.1%)3 (1.1%)Cardiac disorder by AEs31 (11.4%)38 (13.7%)- Grade 1 to 230 (11.0%)37 (13.3%)- Grade 3 to 51 (0.4%)11 (0.4%)21 Grade 3 of Adams-Strokes syndrome occurring 5 months after the completion of 1-year treatment; 2 Grade 5 of acute myocardial infarction occurring 10 days after Cycle 1 of the neoadjuvant therapy

Conclusions Combination therapy of CT-P6 with taxane/anthracycline and monotherapy of CT-P6 over 1 year period were well tolerated and cardiotoxicity was similar to reference trastuzumab.

Citation Format: Esteva FJ, Chung HC, Royce ME, Lee SY, Lee SJ, Stebbing J. Cardiotoxicity in 1 year of treatment with reference trastuzumab and its biosimilar candidate CT-P6 in HER2 positive early stage breast cancer (EBC) patients [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P5-20-14.

The rs4646 and rs12592697 Polymorphisms in CYP19A1 Are Associated with Disease Progression among Patients with Breast Cancer from Different Racial/Ethnic Backgrounds

Given the racial/ethnic disparities in breast cancer, we evaluated the association between CYP19A1 single nucleotide polymorphisms (SNPs) on disease progression in women with breast cancer from different racial/ethnic backgrounds. This is a cross-sectional analysis of data from 327 women with breast cancer in the Expanded Breast Cancer Registry program of the University of New Mexico. Stored DNA samples were analyzed for CYP19A1 SNPs using a custom designed microarray panel. Genotype-phenotype correlations were analyzed. Of the 384 SNPs, 2 were associated with clinically significant outcomes, the rs4646 and rs12592697. The T allele for the rs4646 was associated with advanced stage of the disease at the time of presentation (odds ratio [OR]:1.8, confidence intervals [CI]: 1.05–3.13, p < 0.05) and a more progressive disease (OR: 2.1 [CI: 1.1–4.0], p = 0.04). For the rs12592697, the variant T allele was more frequent in Hispanic women and associated with a more progressive disease (OR: 2.05 [CI: 1.0–4.0], p = 0.04). However, further analysis according to menopausal status showed that the association between these 2 SNPs with disease progression or the stage at diagnosis are confined only to postmenopausal women. The odds ratios of disease progression among postmenopausal women carrying the T allele for the rs4646 and rs12592697 are 3.05 (1.21, 7.74, p = 0.02) and 3.80 (1.24, 11.6, p = 0.02), respectively. Regardless, differences in disease progression among the different genotypes for both SNPs disappeared after adjustment for treatment. In summary, the rs4646 and the rs12592697 SNPs in CYP19A1 are associated with differences in disease progression in postmenopausal women. However, treatment appears to mitigate the differences in genetic risk.

Factors Associated with Interest in Gene-Panel Testing and Risk Communication Preferences in Women from BRCA1/2 Negative Families

Scientific advances have allowed the development of multiplex gene-panels to assess many genes simultaneously in women who have tested negative for BRCA1/2. We examined correlates of interest in testing for genes that confer modest and moderate breast cancer risk and risk communication preferences for women from BRCA negative families. Female first-degree relatives of breast cancer patients who tested negative for BRCA1/2 mutations (N = 149) completed a survey assessing multiplex genetic testing interest and risk communication preferences. Interest in testing was high (70 %) and even higher if results could guide risk-reducing behavior changes such as taking medications (79 %). Participants preferred to receive genomic risk communications from a variety of sources including: primary care physicians (83 %), genetic counselors (78 %), printed materials (71 %) and the web (60 %). Factors that were independently associated with testing interest were: perceived lifetime risk of developing cancer (odds ratio (OR) = 1.67: 95 % confidence interval (CI) 1.06-2.65) and high cancer worry (OR = 3.12: CI 1.28-7.60). Findings suggest that women from BRCA1/2 negative families are a unique population and may be primed for behavior change. Findings also provide guidance for clinicians who can help develop genomic risk communications, promote informed decision making and customize behavioral interventions.

Breast Cancer Management with Melanie E Royce: BOLERO-4 Phase II trial of first-line everolimus plus letrozole in ER+, HER2- advanced breast cancer

Melanie E Royce* speaks to Roshaine Wijayatunga, Managing Commissioning Editor: Melanie E Royce is a Professor in the Department of Internal Medicine, Division of Hematology/Oncology at the University of New Mexico Comprehensive Cancer Center (UNM CCC) in Albuquerque, NM, USA. She received her PhD and MD degrees at the University of Cincinnati, Ohio; then completed her Internal Medicine Residency at Yale University-New Haven Hospital in Connecticut and Medical Oncology Fellowship at The University of Texas MD Anderson Cancer Center in Houston, Texas where she subsequently joined the faculty until she moved to Albuquerque, to be one among the first batch of oncology faculty recruits to help establish an National Cancer Insititute (NCI)-designated CCC in the state of NM.  At UNM CCC, she serves as the Director of the Multidisciplinary Breast Cancer Clinic and Programs and Co-Leader of the Women’s Cancer Program. She is engaged in the care of breast cancer patients and is the Principal Investigator for several breast cancer clinical trials at the UNM CCC. On a national level, she serves on the Breast Cancer Committee of the Southwest Oncology Group and the NCI Breast Oncology Local Disease Task Force. Beyond breast cancer, she has a wider involvement in clinical research being the Director of the Clinical Protocol and Data Management of the UNM CCC and the contract Principal Investigator for the NM Minority/Underserved NCI Community Oncology Research Program, a grant that enhances patient and provider access to NCI-led clinical trials. The NM NCI Community Oncology Research Program in partnership with the NM Cancer Care Alliance, a state-wide clinical trials consortium, facilitates access to an expansive array of clinical trials to virtually all cancer patients statewide.

Abstract P1-09-05: Survival disparities: Quality of care apparently not the answer

Introduction: In New Mexico (NM), Hispanic women have a 1.6-fold increased risk of breast cancer-specific death compared to non-Hispanic white women. In previous studies, race/ethnic minority women have been less likely to receive recommended adjuvant treatments, including radiation in women undergoing breast conservation, and hormonal therapy.

Objective: To determine whether non-receipt of recommended therapies contributed to disparate survival.

Methods: We conducted a case-cohort study of breast-cancer-specific survival within a population-based cohort of first invasive breast cancer diagnosed in white females from 1997-2009 in six NM counties, identified through Surveillance Epidemiology End Results (SEER). We selected fifteen percent of all women diagnosed with breast cancer and all breast cancer deaths. After IRB approval, data were collected from comprehensive medical chart reviews, supplemented by SEER information. Receipt of standard of care, vs. not, was defined based on age, diagnosis year and tumor characteristics, according to changes in treatment guidelines. Women who had a reported contraindication or refused therapy were omitted from assessment of quality of care for that therapy. Cox proportional hazards models for case-cohort were conducted using weighted estimates, with calculation of robust variance and hazard ratios (HR) and 95% confidence intervals (CI), using an alpha level of .05. Analyses were restricted to women of age 70 or less who survived at least 12 months. The proportional hazards assumption was verified by Schoenfeld residuals. All analyses were adjusted for age.

Results: Comprehensive medical records reviews were completed for 91% of eligible women (674 cohort members, 519 breast cancer deaths; median follow up 7.8 years). All others were omitted from analysis. Of women eligible for guideline-based treatment, receipt of guideline-appropriate therapy did not differ by Hispanic ethnicity for any treatment, and Hispanic women were slightly more likely overall to receive appropriate therapy (difference not significant). Among guideline-eligible women, at least 91% received radiotherapy, 78% received chemotherapy, 82% received endocrine therapy, and 89% received anti-HER2 targeted agents. After adjustment for other treatment, lack of receipt of guideline-appropriate therapy was related to an increased risk of breast cancer death for endocrine (HR 1.76; 95% CI 1.09-2.84) and radiation therapy (HR 2.05; 95% CI 1.14-3.69). The few HER2-positive women not treated precluded further assessment. After accounting for endocrine and radiation therapy the survival disparity HR of 1.6 in Hispanic women was reduced to 1.57 suggesting only 2% of the disparity was due to differences in receipt of these treatments.

Conclusion: Limitations include likely undercounts of appropriate therapy, thus proportions cited are minimal estimates. Appropriate therapy includes only documented receipt as therapy completion could not always be assessed. Hispanic women have a disproportionately higher breast cancer mortality despite apparently receiving adjuvant therapies to a similar degree as non-Hispanic white women. Equalizing standard of care and attempting to reduce treatment disparities may not be sufficient to address the disproportionate mortality in Hispanic women.

Citation Format: Friend SC, Royce ME, Kang H, Lomo L, Barry M, Wiggins C, Prossnitz E, Hill DA. Survival disparities: Quality of care apparently not the answer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-09-05.

Everolimus in the Treatment of Metastatic Breast Cancer

The discovery of the mammalian target of rapamycin (mTOR) molecular pathway has brought insight into its vital role in breast cancer pathogenesis. Several clinical trials have shown that the mTOR inhibitor everolimus could improve patient outcomes in several subtypes of breast cancer, including hormone receptor–positive, human epidermal growth factor receptor–negative metastatic disease that has progressed after prior endocrine therapy. This review summarizes findings from clinical trials that have demonstrated the benefit of everolimus in metastatic breast cancer and highlights some new research directions utilizing everolimus.

Introduction of D-phenylalanine enhanced the receptor binding affinities of gonadotropin-releasing hormone peptides

The purpose of this study was to examine whether the introduction of D-Phe could improve the GnRH receptor binding affinities of DOTA-conjugated D-Lys(6)-GnRH peptides. Building upon the construct of DOTA-Ahx-(D-Lys(6)-GnRH1) we previously reported, an aromatic amino acid of D-Phe was inserted either between the DOTA and Ahx or between the Ahx and D-Lys(6) to generate new DOTA-D-Phe-Ahx-(D-Lys(6)-GnRH) or DOTA-Ahx-D-Phe-(D-Lys(6)-GnRH) peptides. Compared to DOTA-Ahx-(D-Lys(6)-GnRH1) (36.1 nM), the introduction of D-Phe improved the GnRH receptor binding affinities of DOTA-D-Phe-Ahx-(D-Lys(6)-GnRH) (16.3 nM) and DOTA-Ahx-D-Phe-(D-Lys(6)-GnRH) (7.6 nM). The tumor targeting and pharmacokinetic properties of (111)In-DOTA-Ahx-D-Phe-(D-Lys(6)-GnRH) was determined in MDA-MB-231 human breast cancer-xenografted nude mice. Compared to (111)In-DOTA-Ahx-(D-Lys(6)-GnRH1), (111)In-DOTA-Ahx-D-Phe-(D-Lys(6)-GnRH) exhibited comparable tumor uptake with faster renal and liver clearance. The MDA-MB-231 human breast cancer-xenografted tumors were clearly visualized by single photon emission computed tomography (SPECT) using (111)In-DOTA-Ahx-D-Phe-(D-Lys(6)-GnRH) as an imaging probe, providing a new insight into the design of new GnRH peptides in the future.

Influences of hydrocarbon linkers on the receptor binding affinities of gonadotropin-releasing hormone peptides

Three new DOTA-conjugated GnRH peptides with various hydrocarbon linkers were synthesized to evaluate the influences of the linkers on their receptor binding affinities. The hydrocarbon linker displayed a profound impact on the receptor binding affinities of DOTA-conjugated GnRH peptides. The Aun linker was better than Gaba, Ahx and Aoc linkers in retaining strong receptor binding affinity of the GnRH peptide. DOTA-Aun-(D-Lys(6)-GnRH) displayed 22.8 nM GnRH receptor binding affinity. (111)In-DOTA-Aun-(D-Lys(6)-GnRH) exhibited fast tumor uptake and urinary clearance in MDA-MB-231 human breast cancer-xenografted nude mice. The cellular and biological results provided an insight into the design of new GnRH peptides in the future.

SWOG S0215: a phase II study of docetaxel and vinorelbine plus filgrastim with weekly trastuzumab for HER2-positive, stage IV breast cancer

SWOG trial S0102 showed significant activity of the combination of docetaxel and vinorelbine in HER2-negative metastatic breast cancer (MBC). For HER2-positive patients, additional benefit may occur with the addition of trastuzumab due to its synergy with docetaxel and vinorelbine. Patients with HER2-positive MBC, but without prior chemotherapy for MBC or adjuvant taxane, were eligible. Docetaxel (60 mg/m²) was given intravenously on Day 1, vinorelbine (27.5 mg/m²) intravenously on Days 8 and 15, and filgrastim (5 µg/kg) on Days 2-21 of a 21-day cycle. In addition, patients received weekly infusions of trastuzumab (2 mg/kg) after an initial bolus of 4 mg/kg. The primary outcome was 1 year overall survival (OS), with secondary outcomes of progression-free survival (PFS), response rate, and toxicity. Due to slow accrual (February 2003-December 2006), enrollment was stopped after 76 of 90 planned patients. There have been 32 deaths and 51 progressions among the 74 eligible patients who received treatment. The estimated 1 year OS was 93% (95% CI 84-97%) with a median of 48 months. One-year PFS was 70% (95% CI 58-79%) with a median of 20 months. Response rate for measurable disease was 84%. No deaths were attributed to treatment. Grade 4 toxicities were reported for 19% with neutropenia the most common (15%). The most common grade 3 toxicities (33%) were leucopenia (14%) and fatigue (10%). The combination of trastuzumab, docetaxel, and vinorelbine is effective as first-line chemotherapy in HER2-positive MBC with minimal toxicity. One-year survival estimates are among the highest reported in this population.

The role of antiresorptive therapies in improving patient care in early and metastatic breast cancer

Breast cancer is the second most common cancer among American women and has a high rate of metastasis to bone. Patients regularly undergo adjuvant therapy (chemotherapy or hormonal therapy) following surgical resection of the tumor. In addition to potential direct effects on bone cells, both chemotherapy and hormonal therapy induce ovarian dysfunction and dramatically decrease estrogen levels in both pre- and postmenopausal women. This leads to decreased bone mineral density and increased fracture risk. Antiresorptive therapies (e.g, zoledronic acid and denosumab) have demonstrated efficacy in preventing cancer therapy-induced bone loss in patients with breast cancer and are approved for the prevention of skeletal-related events in patients with bone metastases from breast cancer. This review will focus on the evolving role of these antiresorptive therapies in the care of women with early or metastatic breast cancer.

Synthesis and evaluation of novel gonadotropin-releasing hormone receptor-targeting peptides

The purpose of this study was to develop novel radiolabeled gonadotropin-releasing hormone (GnRH) receptor-targeting peptides for breast cancer imaging. Three novel 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-conjugated GnRH peptides were designed and synthesized. The radiometal chelator DOTA was conjugated to the epsilon or alpha amino group of D-lysine, or the epsilon amino group of L-lysine via an Ahx {aminohexanoic acid} linker to generate DOTA-Ahx-(D-Lys(6)-GnRH1), DOTA-Ahx-(D-Lys(6)-GnRH2) and DOTA-Ahx-(L-Lys(6)-GnRH3), respectively. The conjugation of the DOTA to the epsilon amino group of D-lysine (rather than alpha amino group of D-lysine nor epsilon amino group of L-lysine) maintained the nanomolar GnRH receptor binding affinity. The IC(50) values of DOTA-Ahx-(D-Lys(6)-GnRH1), DOTA-Ahx-(D-Lys(6)-GnRH2) and DOTA-Ahx-(L-Lys(6)-GnRH3) were 36.1 nM, 10.6 mM and 4.3 mM, respectively. Since only DOTA-Ahx-(D-Lys(6)-GnRH1) displayed nanomolar receptor binding affinity, the specific GnRH receptor binding of (111)In-DOTA-Ahx-(D-Lys(6)-GnRH1) was determined in human GnRH receptor membrane preparations. Furthermore, the biodistribution and tumor imaging properties of (111)In-DOTA-Ahx-(D-Lys(6)-GnRH1) were examined in MDA-MB-231 human breast cancer-xenografted nude mice. (111)In-DOTA-Ahx-(D-Lys(6)-GnRH1) exhibited specific GnRH receptor binding and rapid tumor uptake (1.76 ± 0.58% ID/g at 0.5 h postinjection) coupled with fast whole-body clearance through the urinary system. The MDA-MB-231 human breast cancer-xenografted tumor lesions were clearly visualized by single photon emission computed tomography (SPECT)/CT at 1 h postinjection of (111)In-DOTA-Ahx-(D-Lys(6)-GnRH1). The profound impact of DOTA position on the binding affinity of the GnRH peptide provided a new insight into the design of novel radiolabeled GnRH peptides. The successful imaging of MDA-MB-231 human breast cancer-xenografted tumor lesions using (111)In-DOTA-Ahx-(D-Lys(6)-GnRH1) suggested its potential as a novel imaging probe for human breast cancer imaging.

Phase III comparison of standard doxorubicin and cyclophosphamide versus weekly doxorubicin and daily oral cyclophosphamide plus granulocyte colony-stimulating factor as neoadjuvant therapy for inflammatory and locally advanced breast cancer: SWOG 0012

PURPOSE

Patients with inflammatory breast cancer (IBC) or locally advanced breast cancer (LABC) were randomly assigned to 21-day doxorubicin and cyclophosphamide administered for five cycles (standard arm) versus weekly doxorubicin and daily oral cyclophosphamide administered with granulocyte colony-stimulating factor support for 15 weeks (continuous arm). All patients had subsequent weekly paclitaxel for 12 weeks before surgery.

PATIENTS AND METHODS

Patients (n = 372) were randomly assigned to the standard arm (n = 186) or the continuous arm (n = 186) stratified by disease type (LABC, n = 256; IBC, n = 116). The primary outcome was microscopic pathologic complete response (pCR) at surgery. Secondary outcomes included disease-free survival, overall survival, and toxicity.

RESULTS

More patients in the standard arm had grade 3 to 4 leukopenia and neutropenia, but there were more instances of stomatitis/pharyngitis and hand-foot skin reaction in the continuous arm. Assessed among 356 eligible patients, pCR was not different between the treatment groups stratified by disease type (P = .42). In subset analysis, higher pCR rates were observed in the continuous arm versus the standard arm only for stage IIIB disease (P = .0057) and in IBC (P = .06). Comparison of overall survival and disease-free survival showed no difference between treatment groups (P = .37 and P = .87, respectively).

CONCLUSION

No significant clinical benefit was seen for the investigational arm in this trial overall.

Method of detection and breast cancer survival disparities in Hispanic women

BACKGROUND

Hispanic women in New Mexico (NM) are more likely than non-Hispanic women to die of breast cancer-related causes. We determined whether survival differences between Hispanic and non-Hispanic women might be attributable to the method of detection, an independent breast cancer prognostic factor in previous studies.

METHODS

White women diagnosed with invasive breast cancer from 1995 through 2004 were identified from NM Surveillance Epidemiology End Results (SEER) files (n = 5,067) and matched to NM Mammography Project records. Method of cancer detection was categorized as "symptomatic" or "screen-detected." The proportion of Hispanic survival disparity accounted for by included variables was assessed using Cox models.

RESULTS

In the median follow-up of 87 months, 490 breast cancer deaths occurred. Symptomatic versus screen-detection was classifiable for 3,891 women (76.8%), and was independently related to breast cancer-specific survival [hazard ratio (HR), 1.6; 95% confidence interval (95% CI), 1.3-2.0]. Hispanic women had a 1.5-fold increased risk of breast cancer-related death, relative to non-Hispanic women (95% CI, 1.2-1.8). After adjustment for detection method, the Hispanic HR declined from 1.50 to 1.45 (10%), but after inclusion of other prognostic indicators the Hispanic HR equaled 1.23 (95% CI, 1.01-1.48).

CONCLUSIONS

Although the Hispanic HR declined 50% after adjustment, the decrease was largely due to adverse tumor prognostic characteristics.

IMPACT

Reduction of disparate survival in Hispanic women may rely not only on increased detection of tumors when asymptomatic but on the development of greater understanding of biological factors that predispose to poor prognosis tumors.

The effect of adjuvant radiotherapy on mortality differs according to primary tumor location in women with node-positive breast cancer

PURPOSE

To evaluate the prognostic significance of primary tumor location and to examine whether the effect of adjuvant radiotherapy on survival varies according to tumor location in women with axillary node-positive (ALN+) breast cancer (BC).

PATIENTS AND METHODS

Data were abstracted from the SEER database for 24,410 women aged 25-95 years, diagnosed between 1988-1997 with nonmetastatic T1-T2, ALN+ BC. Subgroup analyses were performed using interactions within proportional hazards models. Event was defined as death from any cause. Prognostic variables were selected using Akaike Information Criteria. Joint significances of subgroups were evaluated with Wald test.

RESULTS

Median follow-up was 10 years. In joint models, statistically significant interactions were found between tumor location, nodal involvement, type of surgery, and radiotherapy. Factorial presentation of interactions showed consistent 13% proportional reduction of mortality in all subgroups, except in women with medial tumors with > or = 4 ALN+ treated with mastectomy. In this subgroup, use of radiotherapy was associated with a 16% proportional increase in mortality.

CONCLUSION

Medial tumor location is a significant adverse prognostic factor that should be considered in treatment decision- making for women with ALN+ BC. Improved survival was observed with radiotherapy use in all subgroups, except in women with medial tumors with > or = 4 ALN+ treated with postmastectomy radiotherapy. These findings raise concern that the favorable effect of radiotherapy may be offset by excess toxicities in the latter subgroup.

Paravertebral block for breast surgery: a cost analysis

Abstract #6103

Background: Paravertebral block (PVB) is a form of regional block that has long been used in surgical procedures, including breast surgery. PVB provides intraoperative and postoperative analgesia, decreasing the need for narcotics (NA). It also decreases amounts of general anesthesia (GA) required. NA and GA contribute to postoperative nausea and vomiting, which is decreased with PVB. There has not been a modern cost analysis of PVB in breast surgery. The purpose of this study is to evaluate patient comfort and cost effectivness of PVB in breast surgery.&#x2028; Materials and Methods: A retrospective chart review of 461 breast cases was performed. Mastectomy with or without axillary staging and lumpectomy with axillary staging were included (n=188). Minor breast biopsies, lumpectomies alone, and combined reconstructions/other procedures were excluded. Data collected included whether or not PVB was performed (based on surgeon/patient/anesthesiologist preference), length of stay (LOS), postoperative requirements for NA and antiemetics (AE), and complications from PVB. Patients (pts) were scheduled as inpatient (IP) or outpatient (OP) based on procedure and comorbidities. The data was analyzed for IP and OP groups for LOS. Cost was calculated from NA and AE use and overnight stay.&#x2028; Results: 188 total procedures (125 IP; 63 OP). 88/125 IP had PVB (70%). 57/63 OP had PVB (90%). IP LOS &lt; 24 hrs had 4/5 with PVB (80%); 1/5 without (20%). LOS 24-36 hrs had 46/63 with PVB (73%); 17/63 without (27%). 57 had LOS &gt; 36 hrs; 38/57 with PVB (67%); 19/57 without (33%). OP LOS 0-2 hrs had 41 pts; 39/41 with PVB (95%); 2/41 without (5%). 22 had LOS &gt; 2 hrs; 18/22 with PVB (82%); 4/22 without (18%). There was an overall shorter LOS for both IP and OP with PVB than without (p=0.0151). 152/188 pts required NA (81%). 112/152 received PVB (74%); 40/152 did not (26%). 36/188 did not require NA (19%). 32/36 received PVB (89%); 4/36 did not (11%). There was a difference between those who did and did not receive PVB and NA use (p=0.0257). 86/188 required antiemetics (46%). 59/86 received PVB (69%); 27/86 did not (31%). 102/188 did not require AE (54%). 86/102 received PVB (84%); 16/102 did not (16%). There was a difference between those who did and did not receive PVB and requirements for AE (p=0.0143). Number of doses of NA and AE were summarized as cost values per pt. The average cost for these medications for an IP with PVB was $184 vs $213 without. OP medicine costs with and without PVB was $39 and $111. Overall average cost difference was $29 for IP, $72 for OP. OP also saved $800 overnight charge. For all pts combined, there was a statistical cost difference (p=0.0085). 1/188 pts had a complication (pneumothorax).&#x2028; Discussion: PVB results in less use of postoperative NA and AE in breast surgery. Not only is this reflected in pt comfort, but also a statistically significant cost reduction for both IP and OP procedures and LOS.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6103.

Breast disease: benign and malignant

Breast diseases, both benign and malignant, are common. Typically, young women present with more benign pathologies; however, breast malignancies can occur in young women, especially in those harboring mutations in the BRCA genes, other inherited genetic syndromes associated with increased risk of breast cancer, or familial predisposition for breast cancer. In all women aged 40 and over presenting with abnormalities of the breast, a primary breast cancer should be ruled out because it is the leading cancer among women in developed countries.

Modeling the effect of tumor size in early breast cancer

SUMMARY BACKGROUND DATA

The purpose of this study was to determine the type of relationship between tumor size and mortality in early breast carcinoma.

METHODS

The data was abstracted from 83,686 cases registered in the Surveillance, Epidemiology, and End Results Program of women diagnosed with primary breast carcinoma between 1988 and 1997 presenting with a T1-T2 lesion and no metastasis in whom axillary node dissection was performed: 58,070 women were node-negative (N0) and 25,616 were node-positive (N+). End point was death from any cause. Tumor size was modeled as a continuous variable by proportional hazards using a generalized additive models procedure.

RESULTS

Functionally, a Gompertzian expression exp(-exp(-(size-15)/10)) provided a good fit to the effect of tumor size (in millimeters) on mortality, irrespective of nodal status. Quantitatively, for tumor size between 3 and 50 mm, the increase of crude cumulative death rate (number of observed deaths divided by the number of patients at risk) increased with size from 10% to 25% for N0 and from 20% to 40% for N+.

CONCLUSIONS

The functional relationship of tumor size with mortality is concordant with current knowledge of tumor growth. However, its qualitative and quantitative independence of nodal status is in contradiction with the prevailing concept of sequential disease progression from primary tumor to regional nodes. This argues against the perception that nodal metastases are caused by the primary tumor.

A Phase II Study of Intravenous Exatecan Mesylate (DX-8951f) Administered Daily for Five Days Every Three Weeks to Patients with Metastatic Adenocarcinoma of the Colon or Rectum

BACKGROUND

To evaluate the antitumor activity, toxicities, and pharmacokinetics (PK) of DX-8951f administered as a 30-min infusion daily for 5 days every 3 weeks in patients with fluorouracil-resistant metastatic colorectal carcinoma.

PATIENTS AND METHODS

Sixteen patients were enrolled. All had metastatic colorectal carcinoma resistant to or progressing after chemotherapy containing 5-fluorouracil and no prior chemotherapy with camptothecin derivatives. DX-8951f was administered until disease progression or unacceptable toxicity. Responses were assessed after every two courses.

RESULTS

Fifteen patients were evaluable. Fifty-one courses of therapy were delivered (median 2). Responses were one minor response, six stable disease, and eight progressive disease. The principal adverse event was neutropenia, with grade 3 and 4 toxicities in three and eight patients, respectively. Non-hematologic toxicities were mild to moderate; the most common were fatigue, nausea, and diarrhea. Plasma concentrations of DX-8951 were well described using a linear two-compartment PK model. There was no evidence of nonlinearity in the elimination of PK or auto-inhibition or induction of DX-8951 clearance over the 5 days of administration.

CONCLUSIONS

DX-8951f at this dose and schedule had no significant activity in this patient population. The toxicity profile, mainly hematologic, was consistent with previous reports. The clearance and volume of distribution were not different from those previously reported.

STK15/Aurora-A expression in primary breast tumors is correlated with nuclear grade but not with prognosis

BACKGROUND

DNA amplification on chromosome 20q13 is commonly detected in breast carcinoma and is correlated with poor prognosis. STK15 maps to this amplicon. The objective of the current study was to use immunohistochemistry to determine STK15 expression in primary breast tumors. The authors also explored whether STK15 was a prognostic factor for breast carcinoma by comparing the level of STK15 gene expression with clinical parameters that are known prognostic factors for the disease.

METHODS

Archival mastectomy and lumpectomy specimens, randomly selected, were immunohistochemically stained to determine the STK15 gene expression level. The clinical parameters of these same patients were reviewed retrospectively and analyzed for correlations with STK15 expression level, based on a positive-versus-negative scoring system.

RESULTS

Of the 112 human breast tumor specimens analyzed, 26% stained positively for STK15 by immunohistochemistry. Of the tumors, that stained positively 62.1% had a well-to-moderately differentiated nuclear grade. The correlation between STK15 staining and nuclear grade was nearly statistically significant (P = 0.05). No association was found between STK15 staining and tumor size, lymph node status, or hormone receptor status. Analysis of recurrence-free survival and overall survival rates also failed to reveal a statistically significant difference between the two groups.

CONCLUSIONS

STK15 expression by immunohistochemistry was noted in approximately one-fourth of primary breast tumors. STK15 expression was associated with nuclear grade, but no correlation was found between the other clinical parameters evaluated. Furthermore, no differences were found in survival rates when they were analyzed by level of STK15 staining.

Capecitabine for 5-fluorouracil-resistant brain metastases from breast cancer

We report a case in which brain metastases originating from breast cancer responded to treatment with oral capecitabine. The metastases had progressed and Karnofsky performance status deteriorated despite whole brain irradiation, hormonal treatment, and systemic chemotherapy that included 5-fluorouracil (5-FU). In contrast, 2 months of treatment with oral capecitabine produced a partial response, documented by lesion size on magnetic resonance imaging and an improvement in performance status; both measures continued to improve during 11 months of capecitabine treatment.

Novel chemotherapy agents for colorectal cancer: oral fluoropyrimidines, oxaliplatin, and raltitrexed

Agents now under investigation for treatment of advanced colorectal cancer (CRC) include the oral fluoropyrimidines, oxaliplatin, and raltitrexed. Research efforts directed at finding agents that conveniently and effectively deliver 5-fluorouracil (5-FU) in a protracted fashion have led to the development of several oral fluoropyrimidines. These agents, which include capecitabine; tegafur and uracil plus leucovorin (UFT/LV); eniluracil plus oral 5-FU; and S-1, are convenient and less toxic than intravenous bolus 5-FU. Oxaliplatin has a uniquely different mechanism of action compared with that of 5-FU and has demonstrated activity not only in the first-line treatment setting but also in patients whose disease has progressed during or following 5-FU treatment. In the first-line setting, when oxaliplatin is combined with 5-FU plus LV, response rates and time to disease progression are remarkably improved compared with 5-FU/LV alone. Raltitrexed, a unique thymidylate synthase inhibitor, has undergone extensive phase III evaluation in CRC. The advent of these novel agents has led to development of combined chemotherapy regimens now being introduced into the adjuvant setting.

Phase I and pharmacokinetic study of exatecan mesylate (DX-8951f): a novel camptothecin analog

PURPOSE

To determine the maximum-tolerated dose (MTD), dose-limiting toxicity (DLT), pharmacokinetic (PK) profile, and recommended phase II dose of Exatecan mesylate (DX-8951f) when administered as a 24-hour continuous infusion every 3 weeks to patients with solid tumors.

PATIENTS AND METHODS

Twenty-two patients with advanced solid tumors, all previously treated, and with performance status < or = 2, were entered. The starting dose of DX-8951f was 0.15 mg/m(2); the dose was escalated according to the modified continual reassessment method. The drug was administered until disease progression or until unacceptable toxic effects occurred.

RESULTS

Seven dose escalations were completed, and a total of 53 courses were delivered (median, two courses; range, one to eight courses) during the study. At doses 1.2 mg/m(2) and lower, toxicities were mostly grade 1, primarily hematologic. In the initial cohort of three patients treated at 2.4 mg/m(2), grade 2 hematologic toxicity was observed. Of the six additional patients entered at 2.4 mg/m(2), three had grade 3 or 4 granulocytopenia. At doses higher than 2.4 mg/m(2), DLT granulocytopenia was observed. Nonhematologic toxicities, including nausea, vomiting, diarrhea, fatigue, and alopecia, were mild to moderate. Neither complete nor partial responses were observed, but four patients had stable disease. The PK profile of DX-8951f seemed linear at the doses administered. The plasma clearance, total volume of distribution, and terminal elimination half-life were approximately 3 L/h, 40 L, and 14 hours, respectively.

CONCLUSION

The DLT of this DX-8951f schedule was granulocytopenia for minimally pretreated patients, and both granulocytopenia and thrombocytopenia for heavily pretreated patients. The MTD for both minimally and heavily pretreated patients was 2.4 mg/m(2). DX-8951f seems to have a linear PK profile on the basis of single-dose administration. The recommended phase II dose with this schedule is 2.4 mg/m(2) for minimally pretreated patients. A lower dose should be used for heavily pretreated patients.

Colorectal cancer: chemotherapy treatment overview

Fluorouracil (5-FU) has remained the standard therapy for the treatment of advanced colorectal cancer for over 40 years. Unfortunately, only a minority of patients experience objective clinical response. Discussed herein are attempts to improve on the activity of 5-FU by biochemically modulating its action. In addition, novel agents for the treatment of advanced colorectal cancer (oral fluoropyrimidines, oxaliplatin, and irinotecan) are discussed. Oral fluoropyrimidines (UFT plus leucovorin, capecitabine, eniluracil plus oral 5-FU) provide the convenience of oral delivery with a marked reduction in febrile neutropenia and mucositis. Recent randomized trials with these agents have demonstrated therapeutic activity that is comparable with intravenous schedules of 5-FU plus leucovorin. Compared to 5-FU, both oxaliplatin and irinotecan have uniquely different mechanisms of action and have demonstrated clinical activity in patients whose disease has progressed with 5-FU treatment. Combinations of either irinotecan or oxaliplatin plus 5-FU/leucovorin have demonstrated that the addition of these agents to 5-FU/leucovorin improves response rates and time to progression compared to 5-FU/leucovorin alone. Combination chemotherapy regimens with these novel agents are rapidly being introduced into the adjuvant setting.

Progress in colorectal cancer chemotherapy: how far have we come, how far to go?

Fluorouracil has been the mainstay of treatment for colorectal cancer (CRC) for almost 40 years. Various schedules and biochemical modulators have been investigated in an attempt to improve the therapeutic efficacy of fluorouracil. To date, fluorouracil plus folinic acid represents the standard therapy in CRC for the adjuvant treatment of patients at high risk for relapse and for the first-line treatment of metastatic disease. To gain clinical acceptance, however, oral fluoropyrimidines must confer at least the same survival advantages associated with the optimal intravenous fluorouracil regimens. Irinotecan and oxaliplatin are 2 other novel agents that have mechanisms of action that are uniquely different from those of fluorouracil, with demonstrated activity in patients with fluorouracil-refractory disease. Recent randomised trials comparing fluorouracil plus folinic acid with combinations of either irinotecan or oxaliplatin and fluorouracil plus folinic acid have shown that response rates are improved and time to progression is increased in patients receiving the combination regimens. These regimens are being rapidly introduced in the adjuvant setting, and the role and acceptance of these combination regimens as first-line therapy needs to be defined. Other novel agents being evaluated in the treatment of patients with advanced CRC include oral edrecolomab (monoclonal antibody 17-1A) and tumour vaccines. Future research is focused on enabling clinicians to individualise treatment strategies in patients with CRC, so as to improve clinical outcomes and reduce drug toxicity.

Novel oral chemotherapy agents

The development of anticancer drugs has conventionally focused on intravenous rather than oral regimens. Recently, interest in oral administration of chemotherapy has been stimulated by the discovery of oral fluoropyrimidines, which appear to possess at least an equivalent efficacy and the potential to reduce toxicity compared with intravenous therapies. Using rational drug design, several oral fluoropyrimidines have been developed, including capecitabine, UFT (tegafur and uracil), eniluracil plus oral 5-fluorouracil (5-FU), and S-1. In addition to the oral fluoropyrimidines, other novel agents available for potential oral administration include irinotecan and temozolomide.

Sequential biochemical modulation of fluorouracil with folinic acid, N-phosphonacetyl-L-aspartic acid, and interferon alfa-2a in advanced colorectal cancer

PURPOSE

Several agents have been evaluated for their effect as biochemical modulators of fluorouracil (5-FU) in the treatment of metastatic colorectal carcinoma. In this study, we used folinic acid (FA), N-phosphonacetyl-L-aspartic acid (PALA), and recombinant interferon alfa-2a (IFNalpha-2a) in a sequential order to assess the efficacy of this approach in patients with metastatic colorectal carcinoma.

PATIENTS AND METHODS

Forty-four patients with metastatic colorectal carcinoma were enrolled onto the study. The treatment course consisted of three cycles: (cycle 1) FA 20 mg/m(2) followed by 5-FU 425 mg/m(2) on days 1 to 5; (cycle 2) PALA 250 mg/m(2) on days 29, 36, 43, and 50 and 5-FU 2,600 mg/m(2) as a 24-hour infusion on days 30, 37, 44, and 51; and (cycle 3) IFNalpha-2a 9 million units (MU) three times a week for 5 weeks beginning on day 57, with a continuous infusion of 5-FU 750 mg/m(2) on days 57 to 61, and then weekly bolus of 5-FU 750 mg/m(2)/wk on days 71, 78, and 85. Response was determined after cycle 3.

RESULTS

All patients had a Zubrod performance status >/= 2, measurable disease, and had received no prior chemotherapy for their metastatic disease. A total of 212 cycles were given. Thirty-six patients were assessable for response. No complete responses were seen. Seven patients had a partial response, eight had stable disease, and 15 had progressive disease. The median duration of response was 25 weeks, and the median survival was 53 weeks. Grade 3 and 4 toxic effects included granulocytopenia, stomatitis, diarrhea, rash, nausea, and fatigue.

CONCLUSION

This trial provided no evidence that sequential biochemical modulation of 5-FU in patients with metastatic colorectal carcinoma had any therapeutic advantage over conventional treatment regimens of 5-FU plus FA.

Novel chemotherapeutic agents for gastrointestinal cancers

Although 5-fluorouracil has been the most commonly prescribed chemotherapy agent in the treatment of patients with gastrointestinal malignancies, new agents discussed herein provide options for the treatment of patients with colorectal, gastric, and pancreas cancer. Irinotecan was recently approved for the treatment of patients with colorectal cancer refractory to 5-fluorouracil. It has also been evaluated in chemotherapy-naïve patients both alone and in combination with 5-fluorouracil plus leucovorin or with oxaliplatin. Evaluated primarily in patients with colorectal cancer, oxaliplatin, a novel platinum compound, is an active agent. In combination with 5-fluorouracil and leucovorin, oxaliplatin provides a higher response rate than 5-fluorouracil and leucovorin alone. Furthermore, when oxaliplatin was added to the same 5-fluorouracil-based regimen in which patients had disease progression, clinical activity was observed. Other agents discussed herein are raltitrexed and the oral fluorinated pyrimidines, including uracil:tegafur plus leucovorin, capecitabine, eniluracil plus oral 5-fluorouracil, and S-1. Gemcitabine has been demonstrated to be more effective than 5-fluorouracil in the alleviation of disease-specific symptoms in patients with advanced pancreatic cancer. Gemcitabine also confers a modest survival advantage. Combinations of these novel compounds are evaluated in gastrointestinal malignancies in the advanced disease setting and in adjuvant therapy programs.

Fluoropyrimidines: a critical evaluation

After nearly four decades of clinical experience with the fluoropyrimidines, 5-fluorouracil (5-FU) remains an integral part of chemotherapy for colorectal cancer. A range of 5-FU treatment regimens with or without biochemical modulation are currently used and toxicity appears to be schedule dependent. The use of oral 5-FU was abandoned because of erratic absorption caused by varying levels of dihydropyrimidine dehydrogenase (DPD) found in the gastrointestinal tract. This effect may be overcome by administering agents that are converted to 5-FU or by inhibiting or inactivating DPD. Xeloda((R)) (capecitabine) was designed as an orally administered, selectively tumoractivated(TM) cytotoxic agent which achieves higher levels of 5-FU in the primary tumor than in plasma or other tissues. The United States Food and Drug Administration (FDA) has approved Xeloda for use in patients with metastatic breast cancer resistant to paclitaxel and in whom further anthracycline therapy is contraindicated. Xeloda is also registered in Canada, Switzerland, Thailand and Argentina. In phase II clinical trials in colorectal cancer, Xeloda produced response rates of 21-24% and median time to disease progression of 127-230 days. Other oral agents in development for the treatment of colorectal cancer include tegafur/uracil plus oral leucovorin, S-1 and eniluracil plus oral 5-FU.

Phase II trial of docetaxel for cholangiocarcinoma

The authors evaluated the activity and toxicity of docetaxel given as a 1-hour infusion every 21 days in patients with unresectable cholangiocarcinoma. Seventeen patients with cytologically or histologically confirmed cholangiocarcinoma received intravenous docetaxel over 1 hour, repeated every 21 days. The initial dose of docetaxel was 100 mg/m2, with a subsequent 25% dose reduction for patients experiencing grade 3 or 4 toxicities. Treatment was continued until disease progression or occurrence of intolerable side effects. All patients received premedication with dexamethasone 8 mg by mouth twice daily for 5 days, starting 1 day before docetaxel infusion. Sixteen of the 17 patients were assessable for response and toxicity; one patient was removed from the trial for intercurrent illness. Thirty-eight cycles of docetaxel were delivered (median, two cycles). No complete or partial responses were noted. Fourteen patients had progressive disease, one patient had stable disease, and one patient died of septic shock shortly after starting treatment. Granulocytopenia was the dose-limiting toxicity. Thirteen patients had grade 4 granulocytopenia, 11 of whom required antibiotics for neutropenic fever. Granulocytopenia was the only grade 4 toxicity observed. Grade 3 toxicities included stomatitis, anemia, fatigue, vomiting, and hypotension. Grade 1 or 2 toxicities included alopecia, diarrhea, peripheral edema, myalgias, and anorexia. Administered on this dose and schedule, docetaxel lacked activity in patients with cholangiocarcinoma. The toxicity profile, including dose-limiting granulocytopenia, has been previously described in patients receiving docetaxel.

Identification of DNA sequences required for mouse APRT gene expression

The mouse aprt promoter contains four GC boxes, which bind transcription factor Spl in vitro, and lacks both TATA and CCAAT boxes. Removal of the two most distal GC boxes of this promoter had little effect on APRT enzyme levels produced in a transient expression assay. Deletion of the distal three GC boxes resulted in a 50% reduction, and deletion of all GC boxes resulted in essentially complete loss of APRT activity. There are two predominant transcription start sites which are located within the region containing the GC boxes. The promoter behaved as a relatively strong promoter when compared to the RSV LTR promoter in a transient CAT assay, and operated in one orientation only. No upstream anti-sense transcripts were detected in either mouse CAK or liver cells, confirming that the mouse aprt promoter, unlike some other GC-rich promoters appears not to support bidirectional transcription.