The Canadian Breast Cancer Symposium 2023 Meeting Report.

On 15-16 June 2023, healthcare professionals and breast cancer patients and advocates from across Canada met in Toronto, Ontario, for the 2023 Canadian Breast Cancer Symposium (CBSC.). The CBSC. is a national, multidisciplinary event that occurs every 2 years with the goal of developing a personalized approach to the management of breast cancer in Canada. Experts provided state-of-the-art information to help optimally manage breast cancer patients, including etiology, prevention, diagnosis, experimental biology, and therapy of breast cancer and premalignant breast disease. The symposium also had the objectives of increasing communication and collaboration among breast cancer healthcare providers nationwide and providing a comprehensive and real-life review of the many facets of breast cancer. The sessions covered the patient voice, the top breast cancer papers from different disciplines in 2022, artificial intelligence in breast cancer, systemic therapy updates, the management of central nervous system metastases, multidisciplinary management of ductal carcinoma in situ, special populations, optimization-based individual prognostic factors, toxicity management of novel therapeutics, survivorship, and updates in surgical oncology. The key takeaways of these sessions have been summarized in this conference report.

Case report: Ultrahypofractionated palliative breast radiotherapy for a fungating invasive mammary carcinoma.

Palliative radiotherapy for symptomatic and intact breast tumors must balance convenience, efficacy, and risk of acute toxicity. This case report presents a patient with metastatic breast cancer and an intact fungating primary tumor. She was treated with an ultrahypofractionated radiation therapy, 26 Gy in 5 consecutive daily fractions, with sequential palliative chemotherapy. This resulted in a minimal toxicity profile and significant reduction of tumor burden and symptoms.

Triple-Negative Breast Cancer: A Review of Current Curative Intent Therapies.

Breast cancer is the most commonly diagnosed malignancy in women, with triple-negative breast cancer (TNBC) accounting for 10-20% of cases. Historically, fewer treatment options have existed for this subtype of breast cancer, with cytotoxic chemotherapy playing a predominant role. This article aims to review the current treatment paradigm for curative-intent TNBC, while also reviewing potential future developments in this landscape. In addition to chemotherapy, recent advances in the understanding of the molecular biology of TNBC have led to promising new studies of targeted and immune checkpoint inhibitor therapies in the curative-intent setting. The appropriate selection of TNBC patient subgroups with a higher likelihood of benefit from treatment is critical to identify the best treatment approach.

A Review of Trastuzumab Biosimilars in Early Breast Cancer and Real World Outcomes of Neoadjuvant MYL-1401O versus Reference Trastuzumab.

The reduced cost of trastuzumab biosimilars has led to increased adoption for HER2-positive breast cancer. This review of trastuzumab biosimilars encompasses this development and real world clinical data in early breast cancer. In addition, we present a retrospective study evaluating the total pathological complete response (tpCR) rates (lack of residual invasive cancer in resected breast tissue and axillary nodes), of MYL-1401O to reference trastuzumab (TRZ) in the neoadjuvant setting for HER2+ early breast cancer (EBC) in Alberta, Canada. Neoadjuvant patients with HER2+ EBC treated with TRZ from November 2018-October 2019 and MYL-1401O from December 2019-September 2020 were identified. Logistic regression was used to control for variables potentially associated with tpCR: trastuzumab product, age, pre-operative T- and N-stage, grade, hormone receptor (HR)-status, HER2-status, chemotherapy regimen, and chemotherapy completion. tpCR was 35.6% in the MYL-1401O group (n = 59) and 40.3% in the TRZ (n = 77) group, p = 0.598. After controlling for clinically relevant variables, there was no significant difference in the odds of achieving tpCR in patients treated with TRZ versus MYL-1401O (OR 1.1, 95% CI 0.5-2.4, p = 0.850). tpCR rates were similar for patients treated with MYL-1401O compared to trastuzumab in our real world study of HER2+ neoadjuvant EBC and comparable to pivotal phase 3 trials.

Top 10 research priorities for early-stage colorectal cancer: a Canadian patient-oriented priority-setting partnership.

BACKGROUND: Colorectal cancer, one of the most commonly diagnosed cancers, is now being detected earlier and treatments are improving, which means that patients are living longer. Partnering with Canadian clinicians, patients and researchers, we aimed to determine research priorities for those living with early-stage colorectal cancer in Canada. METHODS: We followed the well-established priority-setting partnership outlined by the James Lind Alliance to identify and prioritize unanswered questions about early-stage (i.e., stages I-III) colorectal cancer. The study was conducted from September 2018 to September 2020. We surveyed patients, caregivers and clinicians from across Canada between June 2019 and December 2019. We categorized the responses using thematic analysis to generate a list of unique questions. We conducted an interim prioritization survey from April 2020 to July 2020, with patients, caregivers and clinicians, to determine a shorter list of questions, which was then reviewed at a final meeting (involving patients, caregivers and clinicians) in September 2020. At that meeting, we used a consensus-based process to determine the top 10 priorities. RESULTS: For the initial survey, 370 responses were submitted by 185 individuals; of the 98 individuals who provided demographic information, 44 (45%) were patients, 16 (16%) were caregivers, 7 (7%) were members of an advocacy group, 26 (27%) were health care professionals and 5 (5%) were categorized as "other." The responses were refined to create a list of 66 unique unanswered questions. Twenty-five respondents answered the interim prioritization survey: 13 patients (52%), 2 caregivers (8%), 3 advocacy group members (12%) and 7 health care professionals (28%). This led to a list of the top 30 questions. The final consensus meeting involved 20 individuals (10 patients [50%], 3 caregivers [15%] and 7 health care professionals [35%]), who agreed to the top 10 research priorities. The priorities covered a range of topics, including screening, treatment, recurrence, management of adverse effects and decision-making. INTERPRETATION: We determined the top research priorities for early-stage colorectal cancer using a collaborative partnership of stake-holders from across Canada. The priorities covered a broad range of topics that could be addressed by future research, including improved screening practices, the role of personalized medicine, the management of adverse effects of treatment, decision-making and prevention of recurrence.

Impact of Value Frameworks on the Magnitude of Clinical Benefit: Evaluating a Decade of Randomized Trials for Systemic Therapy in Solid Malignancies.

In the era of rapid development of new, expensive cancer therapies, value frameworks have been developed to quantify clinical benefit (CB). We assessed the evolution of CB since the 2015 introduction of The American Society of Clinical Oncology and The European Society of Medical Oncology value frameworks. Randomized clinical trials (RCTs) assessing systemic therapies for solid malignancies from 2010 to 2020 were evaluated and CB (Δ) in 2010-2014 (pre-value frameworks (PRE)) were compared to 2015-2020 (POST) for overall survival (OS), progression-free survival (PFS), response rate (RR), and quality of life (QoL). In the 485 studies analyzed (12% PRE and 88% POST), the most common primary endpoint was PFS (49%), followed by OS (20%), RR (12%), and QoL (6%), with a significant increase in OS and decrease in RR as primary endpoints in the POST era (p = 0.011). Multivariable analyses revealed significant improvement in ΔOS POST (OR 2.86, 95% CI 0.46 to 5.26, p = 0.02) while controlling for other variables. After the development of value frameworks, median ΔOS improved minimally. The impact of value frameworks has yet to be fully realized in RCTs. Efforts to include endpoints shown to impact value, such as QoL, into clinical trials are warranted.

Developing a clinical-pathologic model to predict genomic risk of recurrence in patients with hormone receptor positive, human epidermal growth factor receptor-2 negative, node negative breast cancer.

INTRODUCTION: Patients with hormone receptor (HR)-positive, human epidermal growth factor receptor-2 (HER2)-negative, node negative (NN) breast cancer may be offered a gene expression profiling (GEP) test to determine recurrence risk and benefit of adjuvant chemotherapy. We developed a clinical-pathologic (CP) model to predict genomic recurrence risk and examined its performance characteristics. METHODS: Patients diagnosed with HR-positive, HER2-negative, NN breast cancer with a tumour size < 30 mm and who underwent a GEP test [OncotypeDX or Prosigna] in Alberta from October 2017 through March 2019 were identified. Patients were classified as low or high genomic risk. Multivariable logistic regression analysis was performed to examine the associations of CP factors with genomic risk. A CP model was developed using coefficients of regression and sensitivity analyses were performed. RESULTS: A total of 366 patients were eligible (135 were tested using OncotypeDX and 231 with Prosigna). Of these, 64 (17.5%) patients were classified as high genomic risk. On multivariable logistic regression, tumour size > 20 mm (odds ratio [OR], 3.58; 95% confidence interval [CI], 1.84-6.98; P<0.001), low expression of progesterone receptor (OR, 3.46; 95% CI, 1.76-6.82; P<0.001), and histological grade III (OR, 7.24; 95% CI, 3.82-13.70; P<0.001) predicted high genomic risk. A CP model using these variables was developed to provide a score of 0-4. A CP cut-point of 0, identified 56% of genomic low risk patients with a specificity of 98.4%. CONCLUSIONS: A CP model could be used to narrow the population of breast cancer patients undergoing GEP testing.

A multi-centre study comparing granulocyte-colony stimulating factors to antibiotics for primary prophylaxis of docetaxel-cyclophosphamide induced febrile neutropenia.

BACKGROUND: Primary febrile neutropenia (FN) prophylaxis with ciprofloxacin or granulocyte-colony stimulating factors (G-CSF) is recommended with docetaxel-cyclophosphamide (TC) chemotherapy for early-stage breast cancer (EBC). A pragmatic randomised trial compared the superiority of G-CSF to ciprofloxacin and a cost-utility analysis were conducted. METHODS: EBC patients receiving TC chemotherapy were randomised to ciprofloxacin or G-CSF. The primary outcome was a composite of FN and non-FN treatment-related hospitalisation. Secondary outcomes included; rates of FN, non-FN treatment-related hospitalisation, chemotherapy dose reductions/delays/discontinuations. Primary analysis was performed with the intention to treat population. Cost-utility analyses were conducted from the Canadian public payer perspective. RESULTS: 458 eligible patients were randomised: 228 to ciprofloxacin and 230 to G-CSF. For the primary endpoint there was non-statistically significant difference (Risk difference = -6.7%, 95%CI = -13.5%-0.1%, p = 0.061) between ciprofloxacin patients (46,20.2%) and G-CSF (31,13.5%). Patients receiving ciprofloxacin were more likely to experience FN (36/228, 15.8% vs 13/230, 5.7%) than patients receiving G-CSF (p < 0.001). Non-FN treatment-related hospitalisation occurred in 40/228 (17.5%) of ciprofloxacin patients vs 28/230 (12.2%) of G-CSF patients (p = 0.12). There were no differences in other secondary outcomes. G-CSF was associated with an incremental cost-effectiveness ratio of C$1,760,796 per one quality-adjusted life year gained. CONCLUSION: The primary endpoint of superiority of G-CSF over ciprofloxacin was not demonstrated. While there were reduced FN rates with G-CSF, there were no differences in chemotherapy dose delays/reductions or discontinuations. With the commonly used willingness to pay value of C$50,000/QALY, G-CSF use was not cost-effective compared to ciprofloxacin and deserves scrutiny from the payer perspective.

Paraneoplastic acquired haemophilia A in extensive-stage small cell lung cancer (ES-SCLC) in the era of immunotherapy.

Small cell lung cancer (SCLC) is a deadly and rapidly progressive disease that can present with various paraneoplastic syndromes on initial workup. Acquired factor VIII (FVIII) deficiency, also known as acquired haemophilia A (AHA), has been identified as a rare paraneoplastic syndrome in SCLC. Here, we present a 61-year-old woman with a massive gastrointestinal bleed and prolonged activated partial thromboplastin time (PTT) in the emergency department. She was diagnosed with rare paraneoplastic AHA secondary to extensive-stage SCLC (ES-SCLC). She was treated with high-dose steroids and factor bypassing agents, which led to the resolution of bleeding and undetectable FVIII inhibitor levels. She was subsequently treated for ES-SCLC with carboplatin, etoposide and atezolizumab. This case report highlights a rare clinical presentation of paraneoplastic AHA that necessitates prompt recognition in patients with SCLC with ongoing bleeding and elevated PTT.

Research priorities in metastatic breast cancer: A James Lind Alliance Priority Setting Partnership.

Breast cancer remains the most common cancer among women, and the second most common cause of cancer death. With advances in treatment, women are living longer, in some cases many years, with metastatic breast cancer (MBC). These advances are a direct result of research, however, many studies are primarily researcher or industry led, with minimal input from patients and caregivers. The James Lind Alliance (JLA) brings patients, caregivers, and clinicians together in priority setting partnerships (PSPs) to determine key priorities in research. In this study, we utilized the JLA approach to identify unanswered questions on MBC from patient and clinical perspectives and prioritized to reach a top 10. Following the established JLA approach, MBC patients, caregivers, and health care professionals (HCPs) were surveyed to elicit their questions regarding MBC. Research questions were generated from survey responses, and following literature review to ensure the questions were currently not completely answered, an interim prioritization survey was conducted to identify a shortlist of questions taken to a final consensus meeting. One thousand, one-hundred and ninety-four responses were collected from 668 individuals, which were refined into 62 unique unanswered questions. The interim prioritization survey was completed by 174 individuals, and the top 27 questions were taken to a final meeting to determine by consensus the top 10. The top 10 questions cover a wide range of research questions, identified by valuable stakeholders as being priorities. This list can be used to inform prioritization and funding of future MBC research.

Economic analysis of osimertinib in previously untreated EGFR-mutant advanced non-small cell lung cancer in Canada.

INTRODUCTION: Osimertinib improves progression-free survival in previously untreated EGFR-positive advanced non-small cell lung cancer (NSCLC) patients, with marked intracranial response rates. However, its cost-effectiveness in a publically funded health care system has not been established. We assessed the cost-effectiveness of first-line osimertinib from the public payer perspective in the Canadian health care system. METHODS: A Markov model was developed to project the outcomes and direct medical costs of initial treatment with osimertinib or current standard-of-care (SoC) EGFR TKIs, gefinitib or afatinib, in patients with previously untreated EGFR-mutant advanced NSCLC. Clinical and cost input estimates were informed from the available literature. Model outcomes included costs (in 2018 Canadian dollars), life years (LYs), quality-adjusted life-years (QALYs), and the cost utility of osimertinib compared to SoC EGFR TKI, or incremental cost per QALY gained. RESULTS: Initial treatment with osimertinib was associated with a gain of 0.79 QALY [95% confidence interval (CI), 0.74 to 0.83] at an incremental cost of $176,394 CAD (95% CI, 176,383 to 176,405) vs. SoC EGFR TKI (incremental cost-effectiveness ratio [ICER]: $223,133/QALY gained; 95%CI, 198,144 to 252,805). Osimertinib had a 0% probability of being cost-effective at a willingness-to-pay threshold of $100,000 per QALY. Deterministic sensitivity analysis showed that the cost of osimertinib had the largest impact on ICER results. CONCLUSION: At the current marketed price, first-line osimertinib therapy in patients with advanced EGFR-mutant lung adenocarcinoma is not cost-effective in Canada. Reduction of osimertinib cost, for example by 25%, can significantly improve the cost-effectiveness profile.

Drug development for breast, colorectal, and non-small cell lung cancers from 1979 to 2014.

BACKGROUND: Understanding the drug development pathway is critical for streamlining the development of effective cancer treatments. The objective of the current study was to delineate the drug development timeline and attrition rate of different drug classes for common cancer disease sites. METHODS: Drugs entering clinical trials for breast, colorectal, and non-small cell lung cancer were identified using a pharmaceutical business intelligence database. Data regarding drug characteristics, clinical trials, and approval dates were obtained from the database, clinical trial registries, PubMed, and regulatory Web sites. RESULTS: A total of 411 drugs met the inclusion criteria for breast cancer, 246 drugs met the inclusion criteria for colorectal cancer, and 315 drugs met the inclusion criteria for non-small cell lung cancer. Attrition rates were 83.9% for breast cancer, 87.0% for colorectal cancer, and 92.0% for non-small cell lung cancer drugs. In the case of non-small cell lung cancer, there was a trend toward higher attrition rates for targeted monoclonal antibodies compared with other agents. No tumor site-specific differences were noted with regard to cytotoxic chemotherapy, immunomodulatory, or small molecule kinase inhibitor drugs. Drugs classified as "others" in breast cancer had lower attrition rates, primarily due to the higher success of hormonal medications. Mean drug development times were 8.9 years for breast cancer, 6.7 years for colorectal cancer, and 6.6 years for non-small cell lung cancer. CONCLUSIONS: Overall oncologic drug attrition rates remain high, and drugs are more likely to fail in later-stage clinical trials. The refinement of early-phase trial design may permit the selection of drugs that are more likely to succeed in the phase 3 setting. Cancer 2017;123:4672-4679. © 2017 American Cancer Society.

Tumour thrombus of the inferior vena cava extending into the right atrium in the setting of colon cancer.

Tumour thrombus is seen in renal cell and hepatocellular carcinoma, but is rarely reported in colorectal cancer. A woman aged 46 years, with metastatic colonic adenocarcinoma, was found to have a large mass in the inferior vena cava (IVC) extending into the right atrium. Although this lesion was initially thought to be bland thrombus, imaging with contrast-enhanced CT scan and contrast-enhanced ultrasound supported the diagnosis of tumour thrombus. Despite the large size of the lesion, the patient was asymptomatic. Her lack of symptoms, and poor overall prognosis from her cancer led to the decision to avoid aggressive surgical or radiological interventions. Several months later, the patient passed away. At autopsy, there was no evidence of fatal embolisation from the pre-existing thrombus. Diagnosis of tumour thrombus in the IVC is difficult and management can be challenging due to the significant risks associated with treatment options.

A Value-Based Approach to Treatment of HER2-Positive Breast Cancer: Examining the Evidence.

Over the past decade, treatment of HER2-positive breast cancer has been revolutionized with the introduction of targeted therapies. Survival in both early and advanced HER2-positive breast cancer has improved significantly. With evidence for major clinical benefit, it is imperative that health systems evaluate new treatments to maximize the value of health expenditures. Physicians, funding agencies, and policy makers are tasked with analyzing available evidence to ensure that each individual patient receives the optimal treatment in a resource-challenged environment.