Whole-genome and transcriptome analysis enhances precision cancer treatment options.

BACKGROUND: Recent advances are enabling delivery of precision genomic medicine to cancer clinics. While the majority of approaches profile panels of selected genes or hotspot regions, comprehensive data provided by whole-genome and transcriptome sequencing and analysis (WGTA) present an opportunity to align a much larger proportion of patients to therapies. PATIENTS AND METHODS: Samples from 570 patients with advanced or metastatic cancer of diverse types enrolled in the Personalized OncoGenomics (POG) program underwent WGTA. DNA-based data, including mutations, copy number and mutation signatures, were combined with RNA-based data, including gene expression and fusions, to generate comprehensive WGTA profiles. A multidisciplinary molecular tumour board used WGTA profiles to identify and prioritize clinically actionable alterations and inform therapy. Patient responses to WGTA-informed therapies were collected. RESULTS: Clinically actionable targets were identified for 83% of patients, of which 37% of patients received WGTA-informed treatments. RNA expression data were particularly informative, contributing to 67% of WGTA-informed treatments; 25% of treatments were informed by RNA expression alone. Of a total 248 WGTA-informed treatments, 46% resulted in clinical benefit. RNA expression data were comparable to DNA-based mutation and copy number data in aligning to clinically beneficial treatments. Genome signatures also guided therapeutics including platinum, poly-ADP ribose polymerase inhibitors and immunotherapies. Patients accessed WGTA-informed treatments through clinical trials (19%), off-label use (35%) and as standard therapies (46%) including those which would not otherwise have been the next choice of therapy, demonstrating the utility of genomic information to direct use of chemotherapies as well as targeted therapies. CONCLUSIONS: Integrating RNA expression and genome data illuminated treatment options that resulted in 46% of treated patients experiencing positive clinical benefit, supporting the use of comprehensive WGTA profiling in clinical cancer care.

Clinical utility of MRI in the neoadjuvant management of early-stage breast cancer.

BACKGROUND: With the increasing use of neoadjuvant treatment (NAT) for patients with early-stage breast cancer (ESBC), adequate clinical staging is essential to inform treatment. While the use of MRI with NAT has been proposed to help with accuracy of pre-treatment clinical staging, its impact in clinical practice remains controversial. METHODS: A prospective institutional database of patients with ESBC treated with NAT between May 2012 and December 2020 was analyzed in order to compare the management of patients who received an MRI prior to NAT to those who did not. The indications for MRI and correlation of MRI findings to conventional breast imaging were evaluated. The impact of MRI on management was compared between the MRI and non-MRI groups. RESULTS: A total of 530 patients met inclusion criteria. Of these, 186 (35.1%) had an MRI and 344 (64.9%) did not. The most frequent indication for MRI was the determination of disease extent (54.5%). Patients who had an MRI prior to neoadjuvant treatment were significantly more likely to be younger (47 years versus 57 years; p < 0.001) and have multifocal disease (32.3% versus 22.1%; p < 0.05). When compared to conventional imaging, MRI reported a greater extent of disease in the breast (37.6%), more nodal involvement (18.8%), and multifocal disease (15.1%). Additional diagnostic interventions were advised in 52.2% of patients who underwent MRI. Rates of mastectomies were greater in the MRI group (80.0% versus 58.9%; p < 0.05) in addition to more axillary dissections (28.0% versus 17.4%; p < 0.01). Rates of locoregional recurrences were low in both groups, with similar disease-free survival outcomes at 5 years. CONCLUSION: MRI identified significantly more disease in contrast to conventional imaging and lead to more aggressive surgical management. Prospective studies evaluating the role of MRI before NAT and its impact on long-term outcomes are needed.

Impact of sequence order of anthracyclines and taxanes in neoadjuvant chemotherapy on pathologic complete response rate in HER2-negative breast cancer patients.

PURPOSE: Data exploring optimal sequencing of anthracyclines and taxanes as neoadjuvant chemotherapy (NACT) for breast cancer are limited and inconsistent. The objective of this study was to assess the real-world impact of sequence order on pathologic complete response (pCR) and clinical outcomes from NACT. METHODS: Patients with HER2-negative breast cancer treated with NACT from May 2012 to April 2020 were identified from a prospectively collected institutional database. The primary endpoint was to compare rates of pCR (ypT0/isN0) between patients who received anthracyclines followed by taxanes (AC-T) to those who received taxanes followed by anthracyclines (T-AC). Additional endpoints of interest included clinical complete response, downstaging, Neo-Bioscore, conversion to breast-conserving surgery eligibility, relapse-free survival, and overall survival between groups. RESULTS: Of the 283 patients who met eligibility criteria, 187 (66%) received AC-T and 96 (34%) received T-AC. Sequence order did not influence the primary endpoint of pCR rate (19% for AC-T vs. 21% for T-AC, p = 0.752). There were also no significant differences in secondary NACT efficacy outcomes between groups. In the overall cohort, pCR rate was higher in patients with triple-negative breast cancer (TNBC) (32% vs. 13% in hormone-positive cancer, p < 0.001) and grade 3 tumors (31% vs. 12% for grade 1-2 tumors, p < 0.001). CONCLUSIONS: In this real-world analysis of HER2-negative breast cancer patients, there was no differential impact on pCR rate or clinical outcomes from NACT with sequence order of anthracyclines and taxanes. This supports the current variation in prescribing practice.

Impact of Recurrence Score on type and duration of chemotherapy in breast cancer.

Background: The use of Oncotype dx (Genomic Health, Redwood City, CA, U.S.A.) testing has been shown to change treatment decisions in approximately 30% of breast cancer (bca) cases, but research on how Recurrence Score testing has affected the type of chemotherapy offered is limited. We sought to determine if the availability of Oncotype dx testing resulted in a change to the type and duration of chemotherapy regimens used in the treatment of early-stage hormone receptor-positive bca. Methods: In a population-based cohort study, patients treated in the 2 years before the availability of Oncotype dx testing were compared with patients treated in the 2 years after testing availability. Charts were audited and divided into 2 groups: pre-Oncotype dx and post-Oncotype dx. The groups were compared for differences in duration of chemotherapy (12 weeks vs. >12 weeks), types of agents used (anthracycline vs. non-anthracycline), and myelosuppressive potential of the chosen regimen. Results: Of 834 patients who fulfilled the enrolment criteria, 360 fell into the pre-Oncotype dx era, and 474, into the post-Oncotype dx era. An increase of 11.2 percentage points, to 69.5% from 58.3%, was observed in the proportion of patients receiving short-course compared with long-course chemotherapy (p = 0.068). The proportion of patients prescribed anthracycline-containing regimens declined in the post-Oncotype dx era (47.7% pre vs. 32.2% post, p = 0.016). The selection of more-myelosuppressive chemotherapy protocols increased in the post-Oncotype dx era (67.4% pre vs. 78.8% post, p = 0.044). Conclusions: In the present study, the availability of Oncotype dx testing was observed to influence the choice of chemotherapy type in the setting of early-stage bca.

Optimizing vascular access for patients receiving intravenous systemic therapy for early-stage breast cancer-a survey of oncology nurses and physicians.

Background: Despite advances in systemic therapy choices for patients with early-stage breast cancer, optimal practices for intravenous (IV) access remain unknown. That lack of knowledge holds particularly true for the use of central venous access devices (cvads) such as peripherally inserted central catheters (piccs) and implanted vascular access devices (ports). Methods: Using a survey of Canadian oncologists and oncology nurses responsible for the care of breast cancer patients, we evaluated current access practices, perceptions of complications, and perceptions of risk, and we estimated complication rates and evaluated perceived risk factors for lymphedema. Results: Survey responses were received from 25 physicians and 57 oncology nurses. Administration of trastuzumab or an anthracycline was associated with a higher likelihood of a cvad being recommended. Other factors associated with recommendation of a cvad included prior difficult IV access and a recommendation from the chemotherapy nurse. Although the complication rates perceived to be associated with the use of piccs and ports remained high, respondents felt that cvads might improve patient quality of life. Risk factors perceived to be associated with the risk of lymphedema were axillary lymph node dissection, radiation to the axilla, and line-associated infection. Factors known to be unrelated to lymphedema risk (specifically, blood draws and blood pressure measurement) continue to be perceived as posing a higher risk. Conclusions: Despite widespread use of chemotherapy for patients with breast cancer, the type of venous access used for treatment varies significantly, as do perceptions about the risks of cvad use and the risk for lymphedema development. Further prospective studies are needed to identify best-practice strategies.

Perceptions of vascular access for intravenous systemic therapy and risk factors for lymphedema in early-stage breast cancer-a patient survey.

Background: The choice of vascular access for systemic therapy administration in breast cancer remains an area of clinical equipoise, and patient preference is not consistently acknowledged. Using a patient survey, we evaluated the patient experience with vascular access during treatment for early-stage breast cancer and explored perceived risk factors for lymphedema. Methods: Patients who had received systemic therapy for early-stage breast cancer were surveyed at 2 Canadian cancer centres. Results: Responses were received from 187 patients (94%). The route of vascular access was peripheral intravenous line (IV) in 24%, a peripherally inserted central catheter (picc) in 42%, and a surgically inserted central catheter (port) in 34%. Anthracycline-based regimens were associated with a greater use of central vascular access devices (cvads- that is, a picc or port; 86/97, 89%). Trastuzumab use was associated with greater use of ports (49/64, 77%). Although few patients (7%) reported being involved in the decisions about vascular access, most were satisfied or very satisfied (88%) with their access type. Patient preference centred mainly on avoiding delays in the initiation of chemotherapy. Self-reported rates of complications (183 evaluable responses) were infiltration with peripheral IVs (9/44, 20%), local skin infections with piccs (7/77, 9%), and thrombosis with ports (4/62, 6%). Perceived risk factors for lymphedema included use of the surgical arm for blood draws (117/156, 75%) and blood pressure measurement (115/156, 74%). Conclusions: Most patients reported being satisfied with the vascular access used for their treatment. Improved education and understanding about the evidence-based requirements for vascular access are needed. Perceived risk factors for lymphedema remain variable and are not evidence-based.

Efficacy of a global supportive skin care programme with hydrotherapy after non-metastatic breast cancer treatment: A randomised, controlled study.

This study investigated the efficacy of post-treatment hydrotherapy as supportive care for management of persistent/long-lasting dermatologic adverse events (dAEs) induced in breast cancer survivors by adjuvant therapy, and its impact on quality of life (QoL). Patients in complete remission after standardised (neo)adjuvant chemotherapy, surgery and radiotherapy combination treatment for infiltrating HR+/HER2-breast carcinoma were enrolled in this randomised, multicentre controlled study 1-5 weeks after completing radiotherapy. The control group (CG, n = 33) received best supportive care and the treatment group (HG, n = 35) received 3-weeks of specific hydrotherapy. The primary criterion was change in QoL (QLQ-BR23) after hydrotherapy. Clinical grading of dAEs, cancer-related QoL (QLQ-C30), dermatologic QoL (DLQI) and general psychological well-being (PGWBI) were assessed. Significant dAEs were found at inclusion in both groups (n = 261). Most items showed significantly greater improvement in the HG versus CG group: QLQ-BR23 (breast [p = .0001] and arm symptoms [p = .0015], systemic therapy side effects [p = .0044], body image [p = .0139]), some dAE grading, DLQI (p = .0002) and PGWBI (p = .0028). Xerosis (88% of patients at inclusion) completely healed in all HG patients. Specific hydrotherapy is an effective supportive care for highly prevalent and long-lasting dAEs occurring after early breast cancer treatment, including chemotherapy, and leads to improved QoL and dermatologic toxicities.

Neoadjuvant endocrine therapy and window of opportunity trials: new standards in the treatment of breast cancer?

Until recently, the use of neoadjuvant endocrine therapy was mainly restricted to those patients whose general frailty or comorbidities were contraindications to surgery. There is now increased evidence that certain patient populations (i.e. older patients with hormone-receptor positive disease) can gain as good a pathologic response, with considerably less toxicity, from neoadjuvant endocrine therapy than from neoadjuvant chemotherapy. Optimization of neoadjuvant endocrine therapy is therefore an important therapeutic goal. However, possibly of greater importance in the overall management of breast cancer, is the increased interest in exploring the effects of brief periods of endocrine therapy on in vivo biomarkers, in so called window of opportunity trials. These trials can not only be used to identify the mechanisms of action of novel agents but also to predict optimal subsequent adjuvant therapy for individual patients. While this paper will briefly review the history of neoadjuvant endocrine therapy, more emphasis will be on the evaluation of pivotal window of opportunity trials that will likely lead to a long awaited paradigm shift in the management of breast cancer.