Abstract OT3-05-10: A single arm phase II study of palbociclib in combination with tamoxifen as first line therapy for metastatic hormone receptor positive breast cancer

Background: Hormone receptor positive breast cancer is the most commonly diagnosed subset of breast cancer (60-65%). Endocrine therapy is effective for this subset of breast cancer, in both the adjuvant and metastatic settings. Despite advances in endocrine therapy, many patients relapse during or after completing adjuvant therapy and metastatic breast cancer remains incurable. Palbociclib is a reversible, oral, small molecule inhibitor of cyclin dependent kinases 4 and 6 (CDK4/6). CDK4 and CDK6 together with cyclin D have important roles in regulation of the G1/S transition via regulation of the phosphorylation state of retinoblastomaprotein (Rb). Palbociclib showed significantly improved progression-free survival taken together with endocrine agents in treatment of metastatic breast cancer. Preclinical data showed that in combination with tamoxifen, palbociclib had synergistic growth inhibitory activity as well as efficacy in a model of acquired tamoxifen resistance. Combining palbociclib with tamoxifen in first line treatment of metastatic hormone receptor positive breast cancer may offers an appealing alternative to other endocrine combinations. Methods: This is a non-randomized, open-label, single-arm, multicenter, phase II study of palbociclib in combination with tamoxifen in patients with hormone receptor positive/HER2 negative advanced breast cancer. The primary objective is to determine the objective response rate (complete or partial response) based on RECIST 1.1 or MDA Criteria (for patients with bone only disease). Secondary objectives are: safety and tolerability, progression-free survival, clinical benefit rate, 2-year overall survival. Correlative objectives will explore alterations in circulating tumor DNA and changes in gene expression pattern at the time of progression. Eligibility criteria: women or men with diagnosis of hormone receptor positive/ HER2 negative locally advanced or metastatic breast cancer, not amenable to curative surgery; no prior systemic anti-cancer therapy for advanced hormone receptor positive breast cancer; adequate organ function; pre and post menopausal women are allowed. Drug administration: palbociclib dose will be 125 mg orally once daily on days 1-21 of each 28-day cycle; tamoxifen dose will be 20 mg orally once daily for every day of the 28-day cycle. As of June 2017, the study enrolled 10/71 patients and it is still open to enrollment. NCT 02668666; ocdanciu@uic.edu

Citation Format: Danciu OC, Hoskins K, Tamkus D, Truica C, Blaes A, Green L, Liu L, Toppmeyer D, Wisinski K. A single arm phase II study of palbociclib in combination with tamoxifen as first line therapy for metastatic hormone receptor positive breast cancer [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 OT3-05-10.

Abstract P4-10-02: Cancer team approach for implementing survivorship care plans in the breast cancer survivorship clinic

Background: Recommendations from the Institute of Medicine are that cancer patients receive individualized survivorship care plan (SCP) and treatment summary. SCP includes guidelines for monitoring and maintaining health and is a communication tool shared with families and health care providers. Offering SCP and treatment summary to cancer survivors remains challenging due to time and resource limitations, inadequate reimbursement and survivor access.

Methods: Survivorship starts when completing the initial treatment (surgery, chemotherapy or radiation therapy). A team of medical oncologists, nurse practitioner and patient navigator created a process of pre-screening and identifying breast cancer (BC) survivors. SCP and treatment summary were pre-populated, individualized for each patient, then finalized and discussed with the patients during their medical oncology clinic visit. Pre intervention data was retrospectively collected, including all BC cases from March 2014 to March 2015. Post intervention data was prospectively collected over eight weeks. Pre and post intervention SCP completion rates were compared with chi square analysis.

Results: A baseline one year review of 1124 encounters noted 23 of 90 (25%) BC survivors received SCP. Ninety-six encounters occurred during the 8 week pilot period. Sixteen (16.6%) cases met the definition of BC survivor. During the pilot period, 15 out of 16 (93.7%) survivors received the SCP and treatment summary (p <0.0001). After the pilot period, 96.4% of BC survivors were seen in the BC survivorship clinic.

Conclusions: We successfully piloted the implementation of SCP for BC survivors. Our team found that using clinic visit screening and pre-identifying patients that transition into the survivorship program resulted in improvement of compliance with survivorship measures. In BC survivorship clinic we address specific survivorship issues and review SCP and treatment summary.

Citation Format: Danciu OC, Bharadwaj SN, Hoskins K. Cancer team approach for implementing survivorship care plans in the breast cancer survivorship clinic. [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 P4-10-02.

Barriers to breast cancer risk screening

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Background: The U. S. Preventive Services Task Force has recommended that physicians assess and discuss breast cancer risk with their female patients. With this recommendation comes the need to develop strategies for providing breast cancer risk-screening and a need to identify potential barriers to the successful implementation of a risk-screening strategy. Methods: A personalized breast cancer risk profile was offered to all women presenting for a screening mammogram at a community hospital. The profile included a Gail model estimate and analysis of family cancer history to detect hereditary breast cancer syndromes utilizing a pedigree assessment tool developed by the authors. Women with 5 year Gail estimates ≥ 1.66%, lifetime Gail estimate ≥ 15% or increased score with the pedigree assessment tool were considered at increased breast cancer risk. Women in the increased risk cohort received written notification of their risk status and were advised to undergo formal risk assessment either through a free consultation with an advanced practice nurse with expertise in cancer risk assessment or with their primary physician. We analyzed compliance with this recommendation over the 6 month period of time after subjects received the risk notification letter. Results: For the three month study period, 242 women met criteria for the increased risk cohort. Of these, 201 (83%) failed to follow through with the advanced practice nurse for formal risk assessment. Surveys were mailed to all 201 non-compliant subjects to identify reasons for non-compliance and 80 surveys were returned (40%). Reasons given for failure to follow- through with formal risk assessment included: self-perception of “average” breast cancer risk (75%), recent normal screening mammogram (55%), primary care physician had not referred them (18%), absence of breast symptoms (15%), and time constraints (15%). Only 11 subjects (14%) indicated that they had discussed risk results with their physician. Conclusions: The majority of women in our study who requested breast cancer risk estimates failed to act on that information. These results could have implications for design and implementation of a successful breast cancer risk-screening program, and point to the need for better patient education and involvement of primary care physicians in the risk assessment process.

No significant financial relationships to disclose.

Molecular cytogenetic characterization and physical mapping of 12q13-15 amplification in human cancers

Amplification of sequences derived from 12q13-15 is frequent in human sarcomas and brain tumors. Detailed mapping studies of the amplified region are necessary for definition of the impact of these amplification events on the tumor cell phenotype. By using the genes in this region and genomic fragments isolated by chromosome microdissection, we have established a series of ordered probes from 12q13-15 for fluorescence in situ hybridization (FISH) and Southern blot analysis. These probes have been used for physical mapping of two portions of the interval from GLI to D12S8. The centromeric region extends 1.8 Mb from GLI to microclone M79 and contains at least five genes, including the cyclin-dependent kinase gene CDK4. The more telomeric region includes the p53 regulator MDM2 and covers 1.1 Mb. We used the same group of probes to determine the pattern of amplification in three cell lines and three tumor specimens carrying amplified sequences from 12q13-15. In addition, we used a yeast artificial chromosome (YAC) contig of several megabases covering the entire region from SAS to D12S8 for FISH to determine the pattern of amplification in the neuroblastoma cell line NGP-127. The results suggest that the MDM2 and CDK4 regions may be either coamplified or amplified independently, and they illustrate how the map positions of genes and their functions may interact to determine the pattern of DNA amplification in human malignancies.

Recent advances in breast cancer biology

Breast cancer represents a significant worldwide public health problem as well as an excellent model system for examining many aspects of tumor biology and genetics. As the understanding of the biology of breast cancer expands, this new knowledge can be put to use in efforts to diagnose, treat, and prevent breast cancer. In this review we highlight recent advances in breast cancer biology in the areas of genetics, immunobiology, and molecular biology, with particular emphasis on tumor-suppressor genes, minimal disease detection, growth factor receptors, cell cycle regulators, and mediators of apoptosis.

A collaborative survey of 80 mutations in the BRCA1 breast and ovarian cancer susceptibility gene. Implications for presymptomatic testing and screening

OBJECTIVES

To report the initial experience of an international group of investigators in identifying mutations in the BRCA1 breast and ovarian cancer susceptibility gene, to assess the spectrum of such mutations in samples from patients with different family histories of cancer, and to determine the frequency of recurrent mutations.

DESIGN

Nine laboratories in North America and the United Kingdom tested for BRCA1 mutations in DNA samples obtained from a total of 372 unrelated patients with breast or ovarian cancer largely chosen from high-risk families. Three of these laboratories also analyzed a total of 714 additional samples from breast or ovarian cancer cases, including 557 unselected for family history, for two specific mutations that had been found to recur in familial samples.

PARTICIPANTS

A total of 1086 women with either breast or ovarian cancer.

MAIN OUTCOME MEASURE

The detection of sequence variation in patients' DNA samples that is not found in sets of control samples.

RESULTS

BRCA1 mutations have now been identified in a total of 80 patient samples. Thirty-eight distinct mutations were found among 63 mutations identified through a complete screen of the BRCA1 gene. Three specific mutations appeared relatively common, occurring eight, seven, and five times, respectively. When specific tests for the two most common mutations were performed in larger sets of samples, they were found in 17 additional patients. Mutations predicted to result in a truncated protein accounted for 86% of the mutations detected by complete screening.

CONCLUSIONS

The high frequency of protein-terminating mutations and the observation of many recurrent mutations found in a diverse set of samples could lead to a relatively simple diagnostic test for BRCA1 mutations. More data must be accumulated to address specifically the sensitivity and specificity of such a diagnostic testing procedure and to better estimate the age-specific risk for breast and ovarian cancer associated with such mutations.

The biology of breast cancer

The progression from normal breast epithelium to metastatic breast cancer is a complex, multistep process. Initially, genetic alterations are thought to confer a growth advantage to individual cells by decreasing tumor-suppressor gene activity or increasing oncogene activity, or both. Further alterations result in the development of cell clones that have the ability to invade adjacent tissue, establish metastatic deposits, and evade immune surveillance. At some point in this process, these malignant cell clones also lose the normal ability to respond to hormonal growth regulatory signals. Recent advances in understanding the genetic alterations, the loss of normal growth regulation, and the development of metastatic potential in breast cancer are reviewed. Factors related to the immunobiology of breast cancer are also discussed.