Male Breast Cancer: a Review on Diagnosis, Treatment, and Survivorship

PURPOSE OF REVIEW

Male breast cancer is a relatively uncommon and rare disease that is often managed based on evidence adopted from trials pertaining to female breast cancer due to low accrual rates or exclusion of males. This is despite the known differences in the biology and epidemiology of this condition. This review provides an update regarding the management and surveillance of male breast cancer.

RECENT FINDINGS

Men with breast cancer tend to undergo more extensive surgery in the breast and axilla. The outcomes of male breast cancer compared to a similar subtype of female breast cancer appear worse when matched for stage. Systemic therapies remain predominantly based on recommendations for female breast cancer, although tamoxifen is the more optimal endocrine therapy for men than women. Surveillance with mammograms is recommended for patients harboring a breast cancer susceptibility gene but is otherwise not advised for men who have undergone a mastectomy. Notably, the role of other imaging modalities, including ultrasound and magnetic resonance imaging, is minimal. Although the focus on survivorship care among men is low, it is abundantly clear that this is a stigmatizing diagnosis for men, and they suffer from long-term physical and psychological sequelae following a diagnosis and treatment of breast cancer. In summary, providing more gender-inclusive care and advocating for increased representation of men in prospective breast cancer studies and clinical trials may help improve outcomes and provide enhanced support for this population.

Social Media as a Tool to Directly Address Misinformation in Health Care and Promote Patient Education

PURPOSE/OBJECTIVE(S)

Social media plays an important role in the lives of many, including cancer patients. A majority of cancer patients rated the internet as their most important source of information, and many joined social media as a result of their diagnosis. Most online platforms health care information has not been vetted by healthcare professionals. Although readily available and easy to access, the questionable accuracy of this information poses risks for patients. We aim to assess the feasibility of an online platform led by health care professionals to engage cancer patients on social media to directly address misinformation through targeted patient education. We hypothesized that social media-based cancer information will be a well utilized tool that cancer patients could engage with for information and support regarding their diagnosis.

MATERIALS/METHODS

A social media-based campaign called Cancer Real Talk was initiated on Instagram and TikTok, and a corresponding website for the campaign was launched. Topics were identified based on anecdotal experience with patient misconceptions of care and included the role of palliative care, relationship between cancer and sugar, clinical trials, patient radioactivity, cancer screenings, risks associated with excess vitamin intake, and surgery for lung cancer. Video reels were reviewed by two physicians and published with corresponding text on the two social media platforms with the goal of providing factual and relatable information. Metrics including views and "likes" were gathered based on available data on each platform at 1 day, 1 week, 1 month, and long-term (>3 months) data points.

RESULTS

Between July 2022 and January 2023, a total of seven posts were disseminated through both platforms. Views and likes TikTok and Instagram, respectively, are located in Table 1 with Instagram data bolded. At the last check, the Instagram and TikTok accounts had 272 and 231 followers, respectively.

CONCLUSION

Our posts confirmed engagement with social media users and this educational initiative. Variable engagement highlights the need for increased understanding of how and where to engage with patients on social media. Health care outreach and education has the potential to help patients address misinformation and better navigate their cancer care, which is often quite daunting and complex. Future directions include patient collaboration.

Abstract P5-07-13: Effect of a 12 Week Virtual Supervised Exercise Program on Cardiorespiratory Fitness in Breast Cancer Patients Undergoing Chemotherapy: Results from the STRENGTH Trial

Background: Chemotherapy (CTX) for breast cancer (BC) can have a detrimental effect on cardiorespiratory fitness (CRF), as measured by VO2max. This decline may be attenuated by physical activity, which can also reduce mortality risk and improve quality of life (QoL) for patients (pts) with BC. During the COVID-19 pandemic, many have pivoted to home-based exercise routines, which have been shown to be safe and feasible for pts with BC receiving CTX. We conducted the STRENGTH Trial to evaluate the effect of a 12-week virtual supervised exercise program in BC pts receiving CTX on CRF. Methods: This is a single-center, prospective, single-arm study designed to evaluate the effect of a 12-week virtual supervised exercise training program on CRF in BC pts receiving CTX. Participants aged ≥18 years with stage I-IV BC who were planned to receive at least 12 weeks of CTX of investigator’s choice were eligible for inclusion. Participants were asked to complete a total of 150 minutes (min) of moderate intensity physical activity/week, as a combination of a 45 min weekly virtual personal training session and workout classes streamed from the Peloton® Digital platform (i.e. walking, running, cardio, yoga, strength training, and cycling). The primary endpoint was the distance walked on a Six-Minute Walk Test (6MWT), an accepted surrogate marker for VO2max, at the start and completion of the program. Secondary endpoints included assessment of QoL using the Functional Assessment of Cancer Therapy - General (FACT-G) and symptom assessment using the MD Anderson Symptom Inventory (MDASI) questionnaires at the beginning, middle and end of the study. Exploratory endpoints included treatment adherence, toxicities, completion and response. Results: 33 participants signed consent for the clinical trial and 2 withdrew voluntarily prior to beginning the program. 5 participants discontinued prematurely due to a diagnosis of COVID-19 (N=3) and pulmonary embolism (N=2) and were not included in the primary endpoint. One participant remains on study at this time. Median age 49 yrs; range 33-68. Mean BMI 29.55; range 18.1-46.5. 13 HR+/HER2-, 7 HR-/HER2-, 11 HER2+. 14 (45%) pts had Stage I, 11 (35%) pts had Stage 2, 5 (16%) pts had Stage 3, 1 (3%) pt had Stage 4. 23 pts (70%) received either an anthracycline or HER2-based therapy. 19 pts (61%) received neoadjuvant CTX on study, 11 pts (35%) received adjuvant CTX and 1 pt (3%) received treatment in metastatic setting. The average number of exercise min per week per participant was 123.2 min (95% CI, 104.1-142.2), with a relative dose intensity of 82%. In the pts that completed the study thus far (N=25), there was no statistically significant difference between the distance walked during the 6MWT at the start and end of the study (median difference= -10m, range: -129-150m, p= 0.67). There was no statistically significant difference in the FACT-G score at the start and end of the study (median difference= -1.0, range -17.83- 30.0, p=0.54). Pts scored higher on the MDASI (median difference= 0.33, range -1.55-4.62, p=0.04) at the end of the exercise program compared to the beginning. There were no new or unexpected treatment toxicities observed. Conclusion: Pts who participated in a 12-week virtual supervised exercise program during CTX for BC did not experience a statistically significant difference in the distance walked during the 6MWT between the beginning and end of the exercise program. Exercise may attenuate the decline in cardiorespiratory function that has historically been observed with CTX for BC. Some pts were not able to adhere to the recommended 150 min of exercise/week suggesting a potential need for modified exercise targets for pts with BC undergoing CTX. This study is limited by a small sample size and larger, randomized clinical trials are needed to further evaluate optimal exercise recommendations for patients with BC undergoing CTX in order to maintain and potentially, even improve, cardiorespiratory function.

Citation Format: Eleonora Teplinsky, Amanda Podolski, Kasey Bessada, John Rutledge, Benita Burke, Moira Christoudias, Laura Klein, Kariann Abbate. Effect of a 12 Week Virtual Supervised Exercise Program on Cardiorespiratory Fitness in Breast Cancer Patients Undergoing Chemotherapy: Results from the STRENGTH Trial [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P5-07-13.

Let our patients shine: Survivorship and health interventions in nutrition and exercise program for breast cancer survivors

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Background: Nutrition and lifestyle interventions are instrumental in modifying cancer risk. These changes are often challenging for patients to make due to residual side effects from active treatment and/or ongoing toxicities from current treatment. The SHINE (Survivorship and Health Interventions in Nutrition and Exercise) Program is a wellness program for patients with breast cancer focusing on three pillars of nutrition, exercise and community in order to improve overall health outcomes and decrease the risk of cancer recurrence. Methods: Participants in SHINE have either been diagnosed with ductal carcinoma in situ (DCIS) and/or stage I-IV breast cancer. They are referred to the program at the three-month breast surgery post-operative follow-up appointment or any time after that. All patients are referred to meet with a registered dietitian (RD) and integrative health coach, who provides counseling and education on how to reduce risk through diet and lifestyle, using evidence-based recommendations. Patients are provided with support and accountability. A collaborative program, the Physician Referred Exercise Program (PREP), was established with our health system’s medical fitness center, Valley Health LifeStyles. Patients undergo a fitness assessment that focuses on aerobic fitness, muscle strength and endurance, flexibility, & functional activity. Each patient then receives an exercise prescription developed by a degreed exercise specialist, taking into account both the physician’s & patient’s recommendations & goals. Results: Each component of the SHINE Program has been developed in various stages due to the COVID-19 pandemic. 336 patients with either DCIS or stage I-IV breast cancer have been seen by the RD from December 2020 through January 2022. Mean number of visits/patient: 1.89 (range 1-8). N = 48 were participants in a 12-week study on the feasibility of nutrition counseling and impact on quality of life (QOL) which is still in progress. 76 patient referrals have been placed to the PREP program from August 2021-February 2022. Multiple community programs (Table) have been created for patients to help them develop shared experiences & camaraderie with each other so that they can better integrate new ideas and lifestyle modifications. Conclusions: The SHINE Program addresses care for the whole person, empowering individuals to live their healthiest lifestyle. Future work will focus on clinical trials to evaluate the benefits of these individual and collective interventions on overall QOL, QOL subscales (physical, psychological, social & spiritual well-being), & survivorship symptoms.[Table: see text]

Online Medical Misinformation in Cancer: Distinguishing Fact From Fiction

It is without question that the Internet has democratized access to medical information, with estimates that 70% of the American population use it as a resource, particularly for cancer-related information. Such unfettered access to information has led to an increase in health misinformation. Fortunately, the data indicate that health care professionals remain among the most trusted information resources. Therefore, understanding how the Internet has changed engagement with health information and facilitated the spread of misinformation is an important task and challenge for cancer clinicians. In this review, we perform a meta-synthesis of qualitative data and point toward empirical evidence that characterizes misinformation in medicine, specifically in oncology. We present this as a call to action for all clinicians to become more active in ongoing efforts to combat misinformation in oncology.

Netiquette for social media engagement for oncology professionals

Social media growth has revolutionized health care, facilitating user-friendly, rapid and global sharing of content. Within oncology, this allows for new frontiers in communication for cancer patients, caregivers and healthcare providers. As more physicians engage in online spaces, it is imperative that there are resources to assist in establishing a professional presence on social media. This article describes how to create a social media identity, best practices for engaging both in patient and caregiver spaces and professional communities, and how to address antagonistic and inappropriate behavior on social media with the goal of helping physicians develop an engaging, productive and enjoyable experience online.

American Society of Clinical Oncology Road to Recovery Report: Learning From the COVID-19 Experience to Improve Clinical Research and Cancer Care

This report presents the American Society of Clinical Oncology's (ASCO's) evaluation of the adaptations in care delivery, research operations, and regulatory oversight made in response to the coronavirus pandemic and presents recommendations for moving forward as the pandemic recedes. ASCO organized its recommendations for clinical research around five goals to ensure lessons learned from the COVID-19 experience are used to craft a more equitable, accessible, and efficient clinical research system that protects patient safety, ensures scientific integrity, and maintains data quality. The specific goals are: (1) ensure that clinical research is accessible, affordable, and equitable; (2) design more pragmatic and efficient clinical trials; (3) minimize administrative and regulatory burdens on research sites; (4) recruit, retain, and support a well-trained clinical research workforce; and (5) promote appropriate oversight and review of clinical trial conduct and results. Similarly, ASCO also organized its recommendations regarding cancer care delivery around five goals: (1) promote and protect equitable access to high-quality cancer care; (2) support safe delivery of high-quality cancer care; (3) advance policies to ensure oncology providers have sufficient resources to provide high-quality patient care; (4) recognize and address threats to clinician, provider, and patient well-being; and (5) improve patient access to high-quality cancer care via telemedicine. ASCO will work at all levels to advance the recommendations made in this report.

Novel biomarker panel based on cellular and soluble checkpoint proteins for PD-1/PD-L1 blockade treatment efficacy

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Background: Although anti-PD-1/PD-L1 therapy has become one of the standard treatments for advanced cancers, its low treatment efficacy (10-30%) has remained a major issue. We sought to perform a detailed immune profiling of cells and soluble proteins in order to characterize key regulators and signaling molecules and identify therapeutic targets and biomarkers that may improve treatment efficacy and diagnosis. Methods: This observational study enrolled 49 advanced cancer patients treated with PD-1/PD-L1 blockade monotherapy. Treatment response was assessed by RECIST 1.1. PBMC and plasma samples were collected at baseline and every 6 weeks following initial treatment. Immune profiling of PBMC was done by multi-parametric flow cytometer, and t-SNE analysis was used to identify key immune subtypes. Soluble proteins were evaluated by LUMINEX assays. Cut-off values were determined by ROC curve analysis. Results: Three unique subtypes of immune cells were identified. The population of CD11c+HLA-DRlowCD80+CD86− CD274+ cells (regDC) at baseline was significantly higher in patients with progressive disease (PD, n=28) than in patients showing clinical benefit (non-PD, n=21; p=0.030). The higher regDC population also correlated with higher levels of IL-8, IL-10, CXCL1, CXCL5, and CXCL11 in plasma. The population of CD4+CD25+CD62L+ T cells (Treg) was also higher in PD patients (p<0.001). A unique subtype of CD4+CD28− T cell, however, was higher in non-PD patients (p<0.001). For the soluble proteins, the levels of sLAG-3 and sGITR in plasma correlated with better clinical outcome in low regDC patients (p=0.004 and 0.044, respectively). The combined biomarker panel (cellular and protein markers) yields high sensitivity (90.5 %) and specificity (82.1 %) for predicting treatment efficacy. Disease control rate (DCR) and median progression free survival (PFS) are shown in the Table. Conclusions: To our knowledge, this pilot study is the first to detect three immune cell subtypes, regDC, Treg and CD4+CD28− cells, associated with clinical outcome in the treatment of PD-1/PD-L1 blockade. Profiling of immune cell subtypes and soluble immune checkpoint proteins can serve to identify therapeutic targets and biomarkers for treatment efficacy. We will report the data with further enrollment. [Table: see text]

A phase I trial of ganetespib in combination with paclitaxel and trastuzumab in patients with human epidermal growth factor receptor-2 (HER2)-positive metastatic breast cancer

BACKGROUND

Targeted therapies in HER2-positive metastatic breast cancer significantly improve outcomes but efficacy is limited by therapeutic resistance. HER2 is an acutely sensitive Heat Shock Protein 90 (HSP90) client and HSP90 inhibition can overcome trastuzumab resistance. Preclinical data suggest that HSP90 inhibition is synergistic with taxanes with the potential for significant clinical activity. We therefore tested ganetespib, a HSP90 inhibitor, in combination with paclitaxel and trastuzumab in patients with trastuzumab-refractory HER2-positive metastatic breast cancer.

METHODS

In this phase I dose-escalation study, patients with trastuzumab-resistant HER2-positive metastatic breast cancer received weekly trastuzumab (2 mg/kg) and paclitaxel (80 mg/m²) on days 1, 8, 15, and 22 of a 28-day cycle with escalating doses of ganetespib (100 mg/m², 150 mg/m², and a third cohort of 125 mg/m² if needed) on days 1, 8, and 15. Therapy was continued until disease progression or toxicity. The primary objective was to establish the safety and maximum tolerated dose and/or recommended phase II dose (RP2D) of this therapy. The secondary objectives included evaluation of the effects of ganetespib on the pharmacokinetics of paclitaxel, and to make a preliminary assessment of the efficacy of the combination therapy.

RESULTS

Dose escalation was completed for the two main cohorts without any observed dose-limiting toxicities. Nine patients received treatment. The median prior lines of anti-HER2 therapy numbered three (range 2-4), including prior pertuzumab in 9/9 patients and ado-trastuzumab emtansine (T-DM1) in 8/9 patients. The most common grade 1/2 adverse events (AEs) were diarrhea, fatigue, anemia, and rash. There were no grade 4 AEs related to ganetespib. The overall response rate was 22% (2/9 patients had partial response) and stable disease was seen in 56% (5/9 patients). The clinical benefit rate was 44% (4/9 patients). The median progression-free survival was 20 weeks (range 8-55).

CONCLUSION

The RP2D of ganetespib is 150 mg/m² in combination with weekly paclitaxel plus trastuzumab. The combination was safe and well tolerated. Despite prior taxanes, pertuzumab, and T-DM1, clinical activity of this triplet regimen in this heavily pretreated cohort is promising and warrants further study in HER2-positive metastatic breast cancer.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02060253 . Registered 30 January 2014.

Safety and efficacy outcomes for patients ages 65 and older treated with dose-dense chemotherapy for epithelial ovarian cancer

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Background: Dose-dense chemotherapy is increasingly more utilized in the adjuvant treatment of patients (pts) with epithelial ovarian, fallopian tube, or primary peritoneal carcinoma (EOC), as compared to the conventional q3 week chemotherapy regimen. The safety and tolerability of the dose-dense regimen in pts ≥65 yrs old has not been well studied. We performed a retrospective analysis of pts with stage II-IV EOC treated at our institution with either regimen. Methods: We identified pts with stage II-IV EOC treated at Northwell Health from 2010-2015 who received adjuvant chemotherapy with the dose-dense (carboplatin q3 weeks/weekly paclitaxel) or the conventional (carboplatin and paclitaxel q3 weeks) regimen. Pts who received IP chemotherapy were excluded. Demographics, adverse events (AEs), dose delays/reductions and efficacy outcomes were evaluated. Results: 38 pts received conventional chemotherapy (median age 68 yrs) and 29 pts received dose-dense chemotherapy (median age 61 yrs). There were no differences in the frequency of grade ≥3 hematologic toxicities b/w the two arms. There were no differences in delayed or missed doses between the two arms but a higher proportion of dose reductions in the dose-dense arm ( P= 0.0472). Among pts treated in the dose-dense arm, 87.5% of women < 65 yrs old had at least one grade ≥3 AE when compared to 38.5% of women ≥ 65 yrs old ( P= 0.0161). There were no differences in dose delays, dose reductions, or missed doses when compared by age in the dose-dense arm. In the dose-dense arm, stage III-IV pts < 65 yrs old had a median time to progression (TTP) of 13.0 mo (95% CI, 6.7-13.8) and a median overall survival (OS) of 48.3 months (95% CI, 11.5-48.3). Pts ≥ 65 yrs old had a median TTP of 10.9 mo (95% CI, 8.7-12.7) and median OS of 35.9 mo (95% CI, 30.8-not reached). There was no difference in TTP ( P= 0.2154) or OS ( P= 0.9260) between the two cohorts. Conclusions: Our institutional experience of administering dose-dense adjuvant chemotherapy to women with EOC suggests that this regimen is likely safe in women ≥ 65 yrs old, with similar efficacy outcomes and should be considered for this population. Further study with larger sample sizes and in prospective trials is warranted.

Family-building After Breast Cancer: Considering the Effect on Adherence to Adjuvant Endocrine Therapy

Adherence to endocrine therapy (ET) is a longstanding problem in breast cancer (BC) survivorship care, particularly among younger women. Younger patients have reported lower ET initiation rates and greater rates of early discontinuation and are considered an "at risk" group for nonadherence. For women who hope to have children in the future, concerns about premature menopause and the implications of postponing childbearing for the 5 to 10 years of ET are widespread. Preliminary evidence suggests that prioritizing fertility, along with concerns about side effects, leads to ET noninitiation and early discontinuation. Clinical efforts to improve adherence might need to consider patients' family-building goals during the course of treatment and to appropriately counsel patients according to their priorities and family-building intentions. Educational materials about family building after cancer are still not consistently available or provided. Helping patients to access trusted informational resources and decision support tools, in conjunction with medical counseling, will promote informed decisions regarding ET adherence and pregnancy that are medically appropriate. Such shared patient-provider decision-making about ET adherence and pregnancy could help to maximize patient autonomy by incorporating their values, preferences, and priorities into decisions, using providers' medical expertise.

Abstract P4-14-21: A phase I trial of ganetespib (heat shock protein 90 inhibitor) in combination with paclitaxel and trastuzumab in patients with human epidermal growth factor receptor-2 positive (HER2+) metastatic breast cancer (MBC)

Introduction: Targeted therapies in HER2+ MBC significantly improve outcomes but efficacy is limited by therapeutic resistance. HSP90 is a molecular chaperone involved in the stability and function of multiple signaling onco-proteins. HER2 is an acutely sensitive HSP90 client and HSP90 inhibition can overcome trastuzumab resistance. Our group reported objective responses with 17-AAG plus trastuzumab in HER2+ MBC. Ganetespib, a synthetic, second generation HSP90 inhibitor has increased potency and tolerability compared with earlier agents. We reported anti-tumor activity in metastatic HER2+ and triple negative breast cancer with single agent ganetespib. Preclinically, HSP90 inhibition has synergistic anti-tumor activity with taxanes and trastuzumab. This study will define the MTD and RP2D of ganetespib plus paclitaxel and trastuzumab in HER2+ MBC.

Methods: In this 3+3 phase I dose escalation study, patients with trastuzumab-resistant HER2+ MBC receive weekly trastuzumab and paclitaxel (80mg/m2) with ganetespib on day 1, 8, 15 of a 28 day cycle. HR+ positive patients are required to have at least one prior line of endocrine therapy. DLT of ganetespib monotherapy is diarrhea and therefore patients receive prophylactic anti-motility agents. Based on prior experience with ganetespib plus docetaxel in NSCLC, only 3 dose levels of ganetespib were explored: 100mg/m2, 150mg/m2 and a 3rd cohort of 125mg/m2, if needed. Secondary endpoints include evaluation of effects of ganetespib on the pharmacokinetics (PK) of paclitaxel and preliminary efficacy assessment.

Results: The dosing cohorts (100 mg/m2 (n=3) and 150 mg/m2 (n=6)) have been completed without any DLTs. Median age was 46 years (range 29-65), median prior lines of chemotherapy and anti-HER2 therapy were 3 (range 2-6) and 3 (range 2-4) respectively, including prior pertuzumab in 9/9 and T-DM1 in 8/9 patients. There were no grade 3/4 adverse events (AEs) related to ganetespib. Most common AEs related to ganetespib were diarrhea, fatigue, anemia and rash. Paclitaxel PK data available from 6/9 patients are not appreciably different from those reported in literature. Overall response rate was 25% (2/8 had PR in 150 mg/m2 cohort; 1 patient was not evaluable), SD in 63% (5/8), and clinical benefit rate (CR+PR+SD&gt;24 weeks) was 50% (4/8). 3 patients remain on study.

Conclusion: The RP2D of ganetespib is 150mg/m2 in combination with paclitaxel and trastuzumab. The combination was safe and well tolerated. Updated PFS and PK data will be presented. Despite prior taxanes, pertuzumab and T-DM1, clinical activity of this triplet regimen in this heavily pre-treated cohort is very promising and together with our prior experience with 17-AAG plus trastuzumab and single agent ganetespib warrants further study in HER2+ MBC. A phase 2 trial is being planned in trastuzumab-refractory HER2+ MBC who have progressed on prior pertuzumab and T-DM1. Additionally, the protocol is amended to assess the safety of ganetespib in combination with paclitaxel, trastuzumab and pertuzumab in the first-line setting.

Citation Format: Jhaveri K, Teplinsky E, Chandarlapaty S, Solit D, Cadoo K, Speyer J, D'Andrea G, Adams S, Patil S, Haque S, Friedman K, Neville D, Esteva F, Hudis C, Modi S. A phase I trial of ganetespib (heat shock protein 90 inhibitor) in combination with paclitaxel and trastuzumab in patients with human epidermal growth factor receptor-2 positive (HER2+) metastatic breast cancer (MBC). [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 P4-14-21.

Hyperactivated mTOR and JAK2/STAT3 Pathways: Molecular Drivers and Potential Therapeutic Targets of Inflammatory and Invasive Ductal Breast Cancers After Neoadjuvant Chemotherapy

INTRODUCTION

Inflammatory breast cancer (IBC) is an aggressive and rare cancer with a poor prognosis and a need for novel targeted therapeutic strategies. Preclinical IBC data showed strong activation of the phosphatidylinositide-3-kinase/mammalian target of rapamycin (mTOR) and Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathways, and expression of inflammatory cytokines and tumor-associated macrophages (TAMs).

PATIENTS AND METHODS

Archival tumor tissue from 3 disease types (IBC treated with neoadjuvant chemotherapy [NAC], n = 45; invasive ductal carcinoma [IDC] treated with NAC [n = 24; 'treated IDC'; and untreated IDC [n = 27; 'untreated IDC']) was analyzed for the expression of biomarkers phospho-S6 (pS6) (mTOR), phospho-JAK2 (pJAK2), pSTAT3, interleukin (IL)-6, CD68 (monocytes, macrophages), and CD163 (TAMs). Surrounding nontumor tissue was also analyzed.

RESULTS

Biomarker levels and surrogate activity according to site-specific phosphorylation were shown in the tumor tissue of all 3 disease types but were greatest in IBC and treated IDC and least in untreated IDC for pS6, pJAK2, pSTAT3, and IL-6. Of 37 IBC patients with complete biomarker data available, 100% were pS6-positive and 95% were pJAK2-positive. In nontumor tissue, biomarker levels were observed in all groups but were generally greatest in untreated IDC and least in IBC, except for JAK2.

CONCLUSION

IBC and treated IDC display similar levels of mTOR and JAK2 biomarker activation, which suggests a potential mechanism of resistance after NAC. Biomarker levels in surrounding nontumor tissue suggested that the stroma might be activated by chemotherapy and resembles the oncogenic tumor-promoting environment. Activation of pS6 and pJAK2 in IBC might support dual targeting of the mTOR and JAK/STAT pathways, and the need for prospective studies to investigate combined targeted therapies in IBC.

Abstract P5-19-23: A phase I clinical trial of ganetespib (heat shock protein 90 inhibitor) in combination with paclitaxel and trastuzumab in human epidermal growth factor receptor-2 positive (HER2+) metastatic breast cancer

Introduction: Targeted therapies in HER2+ metastatic breast cancer (MBC) have significantly improved survival, however efficacy is limited by development of therapeutic resistance. HSP90 is a molecular chaperone involved in the stability and function of multiple signaling onco-proteins. HER2 is an acutely sensitive HSP90 client and HSP90 inhibition can overcome trastuzumab resistance. Ganetespib is a novel, synthetic HSP90 inhibitor with increased potency and tolerability compared with earlier agents. Our group has conducted a single agent ganetespib trial in unselected patients which showed anti-tumor activity in HER2+ and triple negative breast cancer. In addition, preclinical data suggests HSP90 inhibition is synergistic with taxanes with potential for significant clinical activity. Ganetespib has been combined with docetaxel in non-small cell lung cancer, it has not previously been combined with paclitaxel and trastuzumab. This study will define the maximum tolerated dose (MTD) and recommended phase II dose (RP2D) of ganetespib when given with paclitaxel and trastuzumab for patients with HER2+ MBC.

Methods: In this 3+3 phase I dose escalation study, patients with trastuzumab resistant HER2+ MBC receive trastuzumab (4mg/kg loading dose, then 2mg/kg) and paclitaxel weekly (80mg/m2) with ganetespib day 1, 8 ,15 of 28 day cycle. Patients are required to have prior pertuzumab and T-DM1 (prior pertuzumab and T-DM1 are not mandated if heavily pretreated prior to their respective FDA approvals). Hormone receptor positive patients are required to have at least one prior line of endocrine therapy. The single agent dose limiting toxicity (DLT) of ganetespib is diarrhea and therefore patients receive prophylactic anti-motility agents. The anticipated MTD of ganetespib in this combination has been informed by experience with docetaxel and based on this only three dose levels of ganetespib are being explored 100mg/m2, 150mg/m2 and a third intermediate cohort of 125mg/m2, if needed. Secondary endpoints include evaluation of effects of ganetespib on the pharmacokinetics of paclitaxel and preliminary assessment of efficacy of the combination (scans at 8 weeks and every 12 weeks thereafter, RECIST 1.1).

Results: The first dosing cohort has fully enrolled and there were no significant toxicities or DLTs reported. Median age was 48 years (range 39-49), median prior lines of chemotherapy were 4 (range 3-7) and included prior pertuzumab and T-DM1 in all 3 patients. 5 adverse events have been defined as possibly/probably related to ganetespib – grade 2 anemia and leukopenia, grade 1 diarrhea (2 patients), fatigue, and rash. Enrollment to the second and potentially final cohort is underway.

Conclusion: This study will define the RP2D of ganetespib in combination with paclitaxel and trastuzumab. Final safety, pharmacokinetic and preliminary response data for all patients will be presented. This combination, with a novel anti-HER2 agent, has encouraging potential for activity in HER2+ breast cancer which is refractory to other HER2 targeting agents.

Citation Format: Komal Jhaveri, Karen Cadoo, Sarat Chandarlapaty, Eleonora Teplinsky, James Speyer, Gabriella D' Andrea, Sujata Patil, Sofia Haque, Kent Friedman, Scott Heese, Deirdre Neville, Francisco Esteva, Clifford Hudis, Shanu Modi. A phase I clinical trial of ganetespib (heat shock protein 90 inhibitor) in combination with paclitaxel and trastuzumab in human epidermal growth factor receptor-2 positive (HER2+) metastatic breast cancer [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P5-19-23.

Detection of metastases in breast cancer: Is whole body PET/MR better than PET/CT?

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Background: Whole body PET/CT is commonly utilized in breast cancer (BC) patients (pts). Limitations include assessment of treatment response in bone metastases (mets), high physiologic uptake in brain and liver, and cumulative radiation exposure. The site of mets can have prognostic and therapeutic implications. PET/MR, an exciting new hybrid technology, delivers less radiation than PET/CT. Our aim was to compare the differences in metastatic lesion detection using PET/CT & PET/MR in all BC subtypes. Methods: After a single 18-FDG injection, pts had whole body PET/CT for staging and assessment of treatment response. They were transported to another NYU facility & then underwent whole body PET/MR. PET/MR & PET/CT images were each read by a radiologist blinded to prior exams or reports. Number of mets (up to 6) per organ was recorded. 2 experienced radiologists unblinded to imaging and pathology reports served as the “reference standard”. Results: Forty-eight BC pts underwent PET/CT & PET/MR (28 in metastatic setting, 5 for staging & 15 to rule out recurrence). Median age: 55; range 32-79 with 31 ER+/HER2-, 8 ER+/HER2+, 2 ER-/HER2+, 6 ER-/HER2+, 1 unknown. 20 pts had no distant mets on scan. In the remaining 28 pts, the reference standard detected 9 liver, 18 bone, 7 lung/pleura, 5 brain & 10 lymph node (LN) metastases; some patients had ≥1 metastatic site. PET/CT had more false positives (FP) and false negatives (FN) in the detection of mets (Table). PET/MR had 1 FP in the liver. PET/MR accurately detected 2 bone (ER+/HER2-), 3 liver (ER+/HER2-), 2 LN (1 ER+/HER2+; 1 ER+/HER2-) and 5 brain lesions (1 ER+/HER2-; 3 ER-/HER2+; 1 ER+/HER2+) in 10 unique pts that were not identified on PET/CT. 1 liver (ER+/HER2-) and 2 brain mets (ER-/HER2+) identified on PET/MR were previously unknown. Conclusions: Our preliminary data suggest that PET/MR outperformed PET/CT in detecting mets in the liver, brain, LN & possibly bone. Prospective studies of PET/MR are warranted to determine whether early detection of mets, including occult brain mets in HER2+ pts, impacts survival.[Table: see text]

Abstract PD5-6: Sustained hyperactivated mTOR & JAK2/STAT3 pathways in inflammatory breast cancer (IBC): Evidence for mTOR plus JAK2 therapeutic targeting

Background: IBC is an aggressive form of breast cancer with poor prognosis. Combined multi-modality therapy results in a 5 year OS of 30%, underscoring the unmet need for targeted therapy. Our preclinical research in cell lines & xenograft tumor models has identified a role for hyper-activated PI3K/mTOR signaling in IBC. IBC cells express IL-6 and IL-8, which recruit tumor activated macrophages (TAMs) that further induce inflammatory cytokines and activate the JAK2/STAT3 pathway. We investigated the independent and combined activity of these pathways in IBC patient tissues.

Methods: Archived tissue specimens of 42 IBC patients (dx 1999-2009) and 27 non-IBC patients (dx 2001-2005) with invasive ductal carcinoma (IDC) were obtained. Surrounding non-tumor normal tissue from IBC (companion controls) was also utilized. All specimens were analyzed using immunohistochemistry (IHC) and scored by 3 independent pathologists. Results were defined as 0 = negative; 1+,2+ = positive for activated mTOR (P-S6); activated JAK2/STAT3 (P-JAK2; P-STAT3); cytokine (IL-6); macrophage infiltration (CD68) and TAM (CD163). Proportions of IBC cases with positive expression were compared with non-IBC cases (Fisher's exact test) & companion controls (McNemar's test). Clinical & survival data were obtained.

Results: Median age at diagnosis: 46 yrs (31-62) in early stage IBC [EIBC] (n = 37) & 41 yrs (29-57) in pts with de novo metastatic IBC [MIBC] (n = 5). In EIBC, 19/36: HER2+ (1 unk); 8/19: ER+/HER2+; 8/36: ER-/HER2-. In MIBC, all were ER- (1 unk) & 3/4 were HER2+ (1 unk). 88% were rx with neoadjuvant &/or adjuvant anthracycline & taxane w/o adjuvant trastuzumab. There were 24 pt deaths (5/5 MIBC). Median f/u for EIBC: 6.3 yrs and for MIBC: 3.4 yrs. Median OS: 81.4 mo (95% CI lower 48 mo) for EIBC & 41 mo (95% CI 8-81 mo) for MIBC. Median RFS: 18 mo (95% CI 18-79 mo) for 23 pts (13 NED; 1 unk). The non-IBC patients were all stage 2-3 with median age at diagnosis: 58 yrs (39-94). 19/27: ER+; 7/25 HER2+ (2 unk); 15/25 ER+/HER2-; 3/25 ER-/HER2-. 78% were rx with adjuvant anthracycline & taxane, 4% were rx with FEC and 18% did not receive adjuvant chemotherapy. 18% received adjuvant trastuzumab. Median f/u: 8.0 yrs. Median OS: not yet reached and median RFS: 111.3 mo (95% CI lower 34.5 mo). EIBC cases were compared with non-IBC cases & companion controls (Table 1). PS6, pJAK2 and pSTAT3 expression was significantly increased in IBC compared to non-IBC. Of the 29 EIBC patients with complete biomarker data who were PS6+, 28/29 (97%) were JAK2+, 15/29 (52%) were STAT3+, 26/29 (90%) were CD68+, 20/29 (69%) were CD163+ and 28/29 (97%) were IL6+.

Conclusion: This is the first study to validate preclinical findings & show a strong co-association between hyper-activation of mTOR & JAK/STAT pathways in most IBC patient tumors when compared to surrounding non-tumor tissue and non-IBC (IDC) tumors and tissues. These findings suggest a key role for dual blockade of mTOR & JAK/STAT pathways for IBC in phase I trials.

BiomarkerMcNemars p-value: Early Stage IBC vs companion controls (N = 37)Fishers p-value: Early stage IBC (N = 37)vs non-IBC (N = 27)PS6&lt;0.00010.0315pJAK2&lt;0.0001&lt;0.0001pSTAT30.0003&lt;0.0001CD163&lt;0.00010.0908CD68&lt;0.00010.0582IL60.00030.3882

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr PD5-6.

Hyperactivated mTOR and JAK2/STAT3 pathways: Crucial molecular drivers and potential therapeutic targets of inflammatory breast cancer (IBC)

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Background: IBC is an aggressive form of breast cancer with poor prognosis. Combined multi-modality Rx results in a 5 year OS of 30-50%, underscoring the unmet need for targeted Rx. Our preclinical research in cell lines and xenografts identifies a role for activated PI3K/mTOR pathway in IBC. IBC cells express IL-6 and IL-8 and recruit tumor activated macrophages (TAMs) that further induce IL-6, IL-8 and activate the JAK2/STAT3 pathway. We investigated the independent and combined activity of these pathways in IBC tissues. Methods: Archived tissues of 42 IBC pts and 13 controls (nl breast) were analyzed using IHC and scored by 3 independent pathologists. Results defined as: 0, 1+ = neg; 2+ = pos for activated mTOR (P-S6) and 0 = neg; 1+, 2+ = pos for activated nuclear JAK2/STAT3 (P-JAK2; P-STAT3), cytokine (IL-6), macrophage (mØ) infiltration (CD68) and TAM (CD163). Proportions of IBC cases with pos expression were compared with controls (Fishers exact tests). Clinical and survival data were obtained. Results: Median age at diagnosis: 46 yrs (31-62) in early-stage IBC [EIBC] (n=37) and 41 yrs (29-57) in pts with de novo metastatic IBC [MIBC] (n=5). In EIBC, 19/36: HER2+ (1 unk); 8/19: ER+/HER2+; 8/36: ER-/HER2-. In MIBC, all were ER- (1 unk) and 3/4 were HER2+ (1 unk). 88% Rx with neoadjuvant and/or adjuvant anthracycline and taxane w/o adjuvant trastuzumab. 24 pts died (5/5 MIBC). Median OS: 86 mo (95% CI lower 48 mo) for EIBC & 41 mo (95% CI 8-81 mo) for MIBC. Median RFS: 18 mo (95% CI 18-79 mo) for 23 pts (13 NED; 1 unk). All controls: neg for P-S6, JAK2, STAT3 and TAMs and 92% neg for mØ and IL-6. Proportion of IBC with pos expression when compared to controls listed in table (p <0.0001). Of 31 pts with complete biomarker data who were PS6+, 97% had activated JAK2, 58% had activated STAT3, 80% had strong mØ and TAM infiltration and 97% were IL6+. Conclusions: This is the first study that validates preclinical findings and shows a strong association between mTOR, cytokines, TAMs and JAK/STAT pathways in most IBC pt tissues. Findings suggest a key role for dual blockade of mTOR and JAK/STAT pathways in phase I trials. [Table: see text]

Fatal hepatitis B reactivation due to everolimus in metastatic breast cancer: case report and review of literature

Hepatitis B reactivation can occur with cytotoxic chemotherapy in patients with hepatitis B and cancer. Reactivation can occur in a patient with chronic hepatitis, an inactive carrier, or one with resolved hepatitis. Clinical presentation may range from subclinical elevation of liver enzymes to fatal fulminant hepatic failure. Mammalian target of rapamycin inhibitors, which include everolimus, are a new generation of targeted agents that are currently approved for many cancers (since March 2009) including advanced hormone receptor positive, human epidermal growth factor receptor 2-negative breast cancer, in conjunction with exemestane (as of July 2012). We are therefore still learning the various adverse events that occur with this new class of agents. Here, we present an unfortunate case of fatal hepatitis B reactivation in a woman with metastatic breast cancer treated with everolimus and exemestane. We have detailed the controversies around hepatitis B screening prior to immunosuppressive therapy. Clinicians and patients should be aware of this rare but fatal complication prior to everolimus use, and a detailed history, screening for hepatitis B and prophylactic antiviral treatment should be considered.

Hyperactivated mTOR and JAK2/STAT3 pathways: Crucial molecular drivers and potential therapeutic targets of inflammatory breast cancer (IBC)

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Background: IBC is an aggressive form of breast cancer with poor prognosis. Combined multimodality Rx results in 5 year median OS of 30-50%, underscoring the unmet need for novel targeted strategies. Our preclinical research in cell lines and xenografts suggests a role for activated PI3K/AKT/mTOR pathway in IBC. IBC cells not only express high levels of IL-6 and IL-8 but can recruit tumor activated macrophages (TAMs), which can further induce IL-6, IL-8 and activate JAK2/STAT3 pathway. We therefore investigated independent and combined activity of these pathways. Methods: Archived tissue specimens of 42 IBC pts (1999 - 2009) and 13 controls (normal breast) were analyzed using IHC and scored by 3 independent pathologists. Results were defined as: 0, 1+ = neg; 2+ = pos for activated mTOR (phosphorylatedS6) and 0 = neg; 1+, 2+ = pos for activated nuclear JAK2/STAT3 (pJAK2; pSTAT3), cytokine (IL-6), macrophage infiltration (CD68) and TAMs (CD163). Proportion of IBC cases with pos expression were compared to proportion among controls (Fishers exact test). Clinical and survival data were obtained. Results: Median age at diagnosis - 44.5 yrs (29-64). 22 had HER2 overexpression (8 also ER+) and 9 were ER-/HER2-; ER & HER2 unknown for 1 and 2 pts respectively. Majority were Rxed with neoadjuvant anthracycline and/taxane without adjuvant trastuzumab. There were 24 deaths. Median OS: 67 mths (95% CI: lower 41). Proportions of IBC cases with pos expression when compared to controls are listed in the table (Fishers p value: <0.0001). Of the 31 pts with complete biomarker data who were PS6 pos, 97% had activated JAK2 & 58% had activated STAT3 (McNemar’s chi square, p <0.001). 24/31 (80%) showed strong infiltration of macrophages and TAMs. All cases had widespread IL6 staining. Conclusions: This study validates our preclinical findings and shows hyperactivation of mTOR and JAK2 signaling in vast majority of IBC specimens, with close association between mTOR, TAMs, cytokines and JAK2/STAT3 pathways. These findings support a role for dual blockade of mTOR and JAK/STAT pathways in clinical trials. [Table: see text]