Prevention of persistent pain with lidocaine infusions in breast cancer surgery (PLAN): study protocol for a multicenter randomized controlled trial

BACKGROUND

Persistent pain is a common yet debilitating complication after breast cancer surgery. Given the pervasive effects of this pain disorder on the patient and healthcare system, post-mastectomy pain syndrome (PMPS) is becoming a larger population health problem, especially as the prognosis and survivorship of breast cancer increases. Interventions that prevent persistent pain after breast surgery are needed to improve the quality of life of breast cancer survivors. An intraoperative intravenous lidocaine infusion has emerged as a potential intervention to decrease the incidence of PMPS. We aim to determine the definitive effects of this intervention in patients undergoing breast cancer surgery.

METHODS

PLAN will be a multicenter, parallel-group, blinded, 1:1 randomized, placebo-controlled trial of 1,602 patients undergoing breast cancer surgery. Adult patients scheduled for a lumpectomy or mastectomy will be randomized to receive an intravenous 2% lidocaine bolus of 1.5 mg/kg with induction of anesthesia, followed by a 2.0 mg/kg/h infusion until the end of surgery, or placebo solution (normal saline) at the same volume. The primary outcome will be the incidence of persistent pain at 3 months. Secondary outcomes include the incidence of pain and opioid consumption at 1 h, 1-3 days, and 12 months after surgery, as well as emotional, physical, and functional parameters, and cost-effectiveness.

DISCUSSION

This trial aims to provide definitive evidence on an intervention that could potentially prevent persistent pain after breast cancer surgery. If this trial is successful, lidocaine infusion would be integrated as standard of care in breast cancer management. This inexpensive, widely available, and easily administered intervention has the potential to reduce pain and suffering in an already afflicted patient population, decrease the substantial costs of chronic pain management, potentially decrease opioid use, and improve the quality of life in patients.

TRIAL REGISTRATION

This trial has been registered on clinicaltrials.gov (NCT04874038, Dr. James Khan. Date of registration: May 5, 2021).

The Association between Mutational Signatures and Clinical Outcomes among Patients with Early-Onset Breast Cancer

Early-onset breast cancer (EoBC), defined by a diagnosis <40 years of age, is associated with poor prognosis. This study investigated the mutational landscape of non-metastatic EoBC and the prognostic relevance of mutational signatures using 100 tumour samples from Alberta, Canada. The MutationalPatterns package in R/Bioconductor was used to extract de novo single-base substitution (SBS) and insertion-deletion (indel) mutational signatures and to fit COSMIC SBS and indel signatures. We assessed associations between these signatures and clinical characteristics of disease, in addition to recurrence-free (RFS) and overall survival (OS). Five SBS and two indel signatures were extracted. The SBS13-like signature had higher relative contributions in the HER2-enriched subtype. Patients with higher than median contribution tended to have better RFS after adjustment for other prognostic factors (HR = 0.29; 95% CI: 0.08-1.06). An unsupervised clustering algorithm based on absolute contribution revealed three clusters of fitted COSMIC SBS signatures, but cluster membership was not associated with clinical variables or survival outcomes. The results of this exploratory study reveal various SBS and indel signatures may be associated with clinical features of disease and prognosis. Future studies with larger samples are required to better understand the mechanistic underpinnings of disease progression and treatment response in EoBC.

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.

Adjuvant Ovarian Function Suppression in Premenopausal Hormone Receptor-Positive Breast Cancer

Importance

Few oncology studies have assessed the effectiveness of adjuvant ovarian function suppression (OFS) in observational settings for premenopausal hormone receptor-positive breast cancer. Target trial emulation is increasingly used for estimating treatment outcomes in observational cohorts.

Objectives

To describe hormone therapy and OFS treatment patterns (aim 1), examine the association between adding OFS to tamoxifen (TAM) or aromatase inhibitor (AI) and survival (aim 2), and examine the association between duration of hormone treatment (TAM or AI) plus OFS (H-OFS) and survival (aim 3).

Design, Setting, and Participants

This population-based cohort study included all premenopausal, early-stage breast cancer diagnoses between 2010 and 2020 in Alberta, Canada. Target trial emulation was conducted. Eligibility criteria were directly modeled after the Suppression of Ovarian Function Trial (SOFT) and Tamoxifen and Exemestane Trial (TEXT). Participants were followed up for a maximum of 5 years. Data were analyzed from July 2022 through March 2023.

Exposures

For aim 2, exposures were receiving the following baseline treatments for 2 years: AI + OFS (AI-OFS), TAM + OFS (T-OFS), and TAM alone. For aim 3, exposures were a 2-year or greater and a less than 2-year duration of H-OFS.

Main Outcomes and Measures

Recurrence-free survival was the primary outcome of interest. Marginal structural Cox models with inverse probability treatment and censoring weights were used to estimate hazard ratios (HRs), adjusted for baseline and time-varying confounding variables.

Results

Among 3434 female patients with premenopausal, early-stage breast cancer diagnoses (median [IQR] age, 45 [40-48] years), 2647 individuals satisfied SOFT and TEXT eligibility criteria. There were 2260 patients who initiated TAM, 232 patients who initiated T-OFS, and 155 patients who initiated AI-OFS; 192 patients received H-OFS for 2 or more years, and 195 patients received H-OFS for less than 2 years. The 5-year recurrence risks were not significantly lower in AI-OFS vs TAM (HR, 0.76; 95% CI, 0.38-1.33) or T-OFS vs TAM (HR, 0.87; 95% CI, 0.50-1.45) groups. Patients receiving H-OFS for 2 or more years had significantly better 5-year recurrence-free survival compared with those receiving H-OFS for less than 2 years (HR, 0.69; 95% CI, 0.54-0.90).

Conclusions and Relevance

This study found no significant reductions in recurrence risk for AI-OFS and T-OFS compared with TAM alone. H-OFS duration for at least 2 years was associated with significantly improved recurrence-free survival.

Investigating Factors Associated with Postmastectomy Emergency Department Visits: A Population-Based Analysis

BACKGROUND

In 2016, a multi-pronged pathway was implemented across 13 hospitals to improve the mastectomy perioperative care experience with one objective being to safely allow same day surgery mastectomy. While the pathway successfully increased same day mastectomy rates from 1.7 to 73.0%, the rate of postoperative emergency department (ED) visits remained high at > 20%, despite focused interventions to enhance perioperative support.

AIM

To investigate potential factors associated with high postoperative ED visits following mastectomies in Alberta, Canada.

METHODS

Data was collected using the Discharge Abstract Database and the National Ambulatory Care Reporting System database. Eligible patients included all women over 18 years old who underwent a mastectomy province-wide between 2004 and 2020. Patient demographics were collected. Primary outcome of interest was ED visit within 30 days of mastectomy. Univariate and multivariable analyses were performed to identify independent predictors for post-operative ED visits.

RESULTS

A total of 19,974 patients had mastectomy during the study period, of which 4590 (23%) had an ED visit within 30 days of surgery. Independent factors associated with ED visits were increasing age, overnight stay mastectomy, reconstruction, certain comorbidities, and living rurally.

CONCLUSIONS

Post-operative ED visits remain high despite initiating a province-wide surgical pathway in 2016 which emphasizes patient education and improved perioperative care and supports. Currently, the majority of ED visits are manageable in non-emergent settings. Patient populations at higher risk for ED visits groups may benefit from additional targeted support and resources to reduce unplanned ED visits.

Breast Cancer After Reduction Mammoplasty: A Population-Based Analysis of Incidence, Treatment and Screening Patterns

Background

The risk of breast cancer may be decreased in women who undergo reduction mammoplasty. The purpose of this study was to describe the incidence and treatment of breast cancer after reduction mammoplasty and to better understand the use of breast cancer screening modalities in these patients.

Methods

This population-based retrospective analysis utilized the Discharge Abstract Database held by the Canadian Institute for Health Information and the National Ambulatory Care Reporting System to identify all women aged 20 years or older who underwent reduction mammoplasty in Alberta, Canada. The incidence and treatment of breast cancer were compared among patients who underwent reduction mammoplasty and age-sex-matched controls. Imaging utilization, including the use of mammography, ultrasound, and breast biopsy, was also compared.

Results

Between 2003 and 2007, 8021 patients over 20 years old underwent reduction mammoplasty in Alberta. Patients were followed for an average of 12.6 years. Eighty-nine (1.1%) patients who underwent reduction mammoplasty developed breast cancer after surgery, compared to 453 (1.9%) controls (P < 0.0001). Among patients diagnosed with breast cancer, there was no difference in patient and tumor characteristics. Women who underwent reduction mammoplasty were more likely to undergo mastectomy for cancer (41.6% vs 1.5%; P < 0.0001) and were more likely to undergo mammography (66.7% vs 58.7%; P < 0.0001), ultrasound (29.2% vs 26.2%; P < 0.0001) and biopsy for benign disease (7.2% vs 6%, P < 0.0001) compared to controls.

Conclusions

Despite an increased frequency of breast cancer screening, the incidence of breast cancer is lower after reduction mammoplasty compared with women who did not undergo breast reduction. After a diagnosis of breast cancer, surgical treatment patterns differ between groups, whereby mastectomy is more common after reduction mammoplasty.

Improvement in patient-reported pain among patients with metastatic cancer and its association with opioid prescribing

PURPOSE

Opioids are a mainstay of cancer pain management; however, patients with metastatic cancer are often excluded from studies, leading to a lack of evidence on whether increased prescribing (dosage and/or duration) results in improved outcomes for this population. This study aimed to investigate whether increased opioid prescribing is associated with an improvement in patient-reported pain among patients with metastatic cancer.

PATIENTS AND METHODS

A retrospective cohort of all adult patients diagnosed with stage IV cancers, who completed at least two patient-reported outcomes (PROs) within 30 days of each other, was identified from administrative data. Opioid prescriptions were categorized by dosage level and number of prescription days. Multivariable logistic regression was used to investigate the association between opioid prescribing and clinically important improvement in pain score (≥ 1 point change on the Edmonton Symptom Assessment System).

RESULTS

A total of 2169 patients were included, 770 (35.5%) of whom had active opioid prescription between PROs, with an average daily dosage of 86.1 mg of oral morphine equivalent. Active prescription was associated with improvement in pain (OR = 2.17, P < 0.001). However, among patients with active prescription, neither dosage nor number of prescription days was significantly associated with pain improvement.

CONCLUSION

Opioid prescription is important for treating cancer-related pain; however, increased dosage or duration may not be leading to greater improvements in pain. Patients with metastatic cancer who are receiving increased opioid prescribing may have difficult-to-treat pain and may benefit from multidisciplinary pain management strategies to supplement opioid prescription and improve outcomes.

Incorporating Lymphovenous Anastomosis in Clinically Node-Positive Women Receiving Neoadjuvant Chemotherapy: A Shared Decision-Making Model and Nuanced Approached to the Axilla

Introduction: Lymphedema remains a risk for 13–34% of breast cancer patients who require an axillary dissection (ALND) and radiation. Immediate lymphovenous anastomosis (LVA) may mitigate lymphedema by up to 30% by restoring the physiologic lymphatic drainage immediately after ALND. Currently, completion of ALND (cALND) versus radiation after neoadjuvant therapy (NAC) is being addressed by the Alliance A11202 trial, leaving a paucity of data to guide practice. Our study describes the implementation process of LVA into clinical practice after NAC for node-positive breast cancer in the current clinical context. Methods: We reviewed a prospective database of LVA in node-positive patients (cT1-4,Nany) who received NAC followed by axillary surgery ± immediate LVA from October 2021 to 2022. The evolution of the surgical approach is described. Specifically, patients who downstaged to clinically negative nodes post-NAC were offered targeted SLNB with dual-tracer and intraoperative frozen section (FS). Patients were reminded that the standard of care for any node positive is cALND. Immediate cALND with LVA was performed for grossly positive nodes or all positive SLNs; cALND was omitted for those with negative SLNs. For a microscopic disease on a frozen section, a shared decision was made pre-operatively, given each patient’s differing valuations of the benefit and risks of cALND ± LVA versus no cALND with planned regional radiation postoperatively. LVA was offered as an option as part of our institutional evaluation of the procedure. Results: A total of 15 patients were included; the mean age was 49.9 (range 32–75) with stage IIA to IIIB breast cancer. Of these, 6 (40%) were triple negative, 5 (33.3%) HER-2 positive, and 4 (26.7%) ER/PR+ HER-2 negative. There were 13 women (86.7%) who had persistent axillary adenopathy based on clinical and/or ultrasound assessment, with 8 patients proceeding directly to ALND with LVA. Among these patients, 3 (37.5%) had pathologic nodal disease, and 5 (62.5%) were node negative, confirming the limitations of pre-operative imaging. As a result, the subsequent 7 (46.7%) underwent targeted SLNB with FS, with 3 patients (42.9%) avoiding an ALND as a result of a negative FS. A total of 4 patients (57.1%) had 1 or more positive lymph nodes on FS: 3 proceeded with a cALND and LVA, and 1 patient (14.2%) opted for no cALND based on a pre-operative discussion and received adjuvant radiation and chemotherapy. Of the 11 patients who underwent ALND and LVA, 1 patient (9.1%) developed lymphedema at 6.9 months following their surgery. The accuracy, sensitivity, and specificity of pre-operative US were 46.7%, 85.7%, and 12.5% and intraoperative FS were 88.0%, 72.7%, and 100%, respectively. Conclusions: As adjuvant nodal radiation and systemic therapy continue to improve, the benefit of a cALND in patients with the limited residual disease remains unclear as we await the outcomes from clinical trials. In the era of clinical uncertainty, we propose a nuanced approach to the axilla by utilizing a shared decision model with patients, incorporating targeted SLNB with FS and completion node dissection when required and desired by the patient, coupled with LVA in a simple stepwise treatment pathway.

A New Method of Identifying Pathologic Complete Response After Neoadjuvant Chemotherapy for Breast Cancer Patients Using a Population-Based Electronic Medical Record System

BACKGROUND

Accurate identification of pathologic complete response (pCR) from population-based electronic narrative data in a timely and cost-efficient manner is critical. This study aimed to derive and validate a set of natural language processing (NLP)-based machine-learning algorithms to capture pCR from surgical pathology reports of breast cancer patients who underwent neoadjuvant chemotherapy (NAC).

METHODS

This retrospective cohort study included all invasive breast cancer patients who underwent NAC and subsequent curative-intent surgery during their admission at all four tertiary acute care hospitals in Calgary, Alberta, Canada, between 1 January 2010 and 31 December 2017. Surgical pathology reports were extracted and processed with NLP. Decision tree classifiers were constructed and validated against chart review results. Machine-learning algorithms were evaluated with a performance matrix including sensitivity, specificity, positive predictive value (PPV), negative predictive value [NPV], accuracy, area under the receiver operating characteristic curve [AUC], and F1 score.

RESULTS

The study included 351 female patients. Of these patients, 102 (29%) achieved pCR after NAC. The high-sensitivity model achieved a sensitivity of 90.5% (95% confidence interval [CI], 69.6-98.9%), a PPV of 76% (95% CI, 59.6-87.2), an accuracy of 88.6% (95% CI, 78.7-94.9%), an AUC of 0.891 (95% CI, 0.795-0.987), and an F1 score of 82.61. The high-PPV algorithm reached a sensitivity of 85.7% (95% CI, 63.7-97%), a PPV of 81.8% (95% CI, 63.4-92.1%), an accuracy of 90% (95% CI, 80.5-95.9%), an AUC of 0.888 (95% CI, 0.790-0.985), and an F1 score of 83.72. The high-F1 score algorithm obtained a performance equivalent to that of the high-PPV algorithm.

CONCLUSION

The developed algorithms demonstrated excellent accuracy in identifying pCR from surgical pathology reports of breast cancer patients who received NAC treatment.

Outcomes and Healthcare Utilization Among New Persistent Opioid Users and Nonopioid Users After Curative-intent Surgery for Cancer

OBJECTIVE

The aim of the study was to compare the health outcomes and resource use of cancer patients who were new persistent opioid users with those who were not, after undergoing curative intent surgery for cancer.

BACKGROUND

Little is known about long-term health outcomes (overdose, mortality) and resource utilization of new persistent opioid users among cancer patients undergoing curative-intent surgery.

METHODS

This retrospective cohort study included all adults with a diagnosis of solid cancers who underwent curative-intent surgery during the study period (2011-2015) in Alberta, Canada and were opioid-naïve before surgery, with a follow-up period until December 31, 2019. The key exposure, "new persistent opioid user," was defined as a patient who was opioid-naive before surgery and subsequently filled at least 1 opioid prescription between 60 and 180 days after surgery. The primary outcome was opioid overdose that occurred within 3 years of surgery. All-cause death, noncancer caused death, and department visit (yes vs. no), and hospitalization (yes vs. no) in the follow-up periods were also included as outcomes.

RESULTS

In total, 19,219 patients underwent curative intent surgery with a median follow-up of 47 months, of whom 1530 (8.0%) were identified as postoperative new persistent opioid users. In total, 101 (0.5%) patients experienced opioid overdose within 3 years of surgery. Compared with nonopioid users, new persistent opioid users experienced a higher rate of opioid overdose (OR = 2.37, 95% CI: 1.44-3.9) within 3 years of surgery. New persistent opioid use was also associated with a greater likelihood of being hospitalized (OR = 2.03, 95% CI: 1.76-2.33) and visiting an emergency room (OR = 1.83, 95% CI: 1.62-2.06) in the first year after surgery, and a higher overall (HR = 1.28, 95% CI: 1.1-1.49) and noncancer caused mortality (HR = 1.33, 95% CI: 1.12-1.58), when compared with nonopioid users.

CONCLUSION

Postoperative new persistent opioid use among cancer patients undergoing curative-intent surgery is associated with subsequent opioid overdose, worse survival, and more health resource utilization.

The Association between Early-Onset Diagnosis and Clinical Outcomes in Triple-Negative Breast Cancer: A Systematic Review and Meta-Analysis

Early-onset diagnosis, defined by age <40 years, has historically been associated with inferior outcomes in breast cancer. Recent evidence suggests that this association is modified by molecular subtype. We performed a systematic review and meta-analysis of the literature to synthesize evidence on the association between early-onset diagnosis and clinical outcomes in triple-negative breast cancer (TNBC). Studies comparing the risk of clinical outcomes in non-metastatic TNBC between early-onset patients and later-onset patients (≥40 years) were queried in Medline and EMBASE from inception to February 2023. Separate meta-analyses were performed for breast cancer specific survival (BCSS), overall survival (OS), and disease-free survival (DFS), locoregional recurrence-free survival (LRRFS), distant recurrence-free survival (DRFS), and pathological complete response (pCR). In total, 7581 unique records were identified, and 36 studies satisfied inclusion criteria. The pooled risk of any recurrence was significantly greater in early-onset patients compared to later-onset patients. Better BCSS and OS were observed in early-onset patients relative to later-onset patients aged >60 years. The pooled odds of achieving pCR were significantly higher in early-onset patients. Future studies should evaluate the role of locoregional management of TNBC and the implementation of novel therapies such as PARP inhibitors in real-world settings, and whether they improve outcomes.

Abstract P5-03-07: Prevalence of Pathogenic Variants in Cancer Predisposition Genes in Women with Young Onset Breast Cancer

Introduction: Approximately 5% of breast cancers are diagnosed in women 40 years of age or younger. Known risk factors for young-onset breast cancer are few and can only account for a very small proportion of cases. In this study, we evaluated the contribution of mutations in 24 breast cancer predisposition genes in unselected Canadian women diagnosed with breast cancer at age 40 or younger. Methods: This study is a sub-study of the larger Reducing the bUrden of Breast cancer in Young women (RUBY) Study. In the RUBY study, women diagnosed with breast cancer at the age of 40 years or younger are recruited at the time of diagnosis from 33 centres across Canada. Participants in RUBY provided detailed demographic and clinical data, in addition to provision of serial biospecimens. Participants could elect to consent into the genetics substudy, and have genetic testing performed for pathogenic variants in 24 breast cancer predisposition genes, including ATM, BARD1, BRCA1, BRCA2, BRIP1, CDH1, CHEK2, EPCAM, FAM175A, MLH1, MRE11, MSH2, MSH6, NBN, PALB2, PMS2, PTEN, RAD50, RAD51C, RAD51D, RECQL, STK11, TP53 and XRCC2. Sequencing was performed and all potentially pathogenic variants were confirmed with conventional Sanger sequencing. Pathogenic and likely pathogenic mutations were reported for all 24 genes. CanRisk scores for likelihood of having a pathogenic variant in 8 cancer predisposition genes (BRCA1 BRCA2, PALB2, CHEK2, ATM, RAD51C, RAD51D, and BRIP1) were generated for each participant. Results: 714 women consented and genetic testing was performed on the blood samples provided as a component of the RUBY study. The mean age of the participants was 35.8 years (range 23-40 years), and the mean CanRisk score was 13.7 (range 2.3-98.0). Overall, 150 pathogenic mutations (21.0%) were detected in 147 women (three participants had mutations in two genes). The most common pathogenic variants detected were in BRCA1 (48), BRCA2 (40), CHEK2 (24), ATM (10), and PALB2 (9), representing 87.3% of all pathogenic variants identified. The mean CanRisk score was 28.8% (range 3.2-98.0%) for those identified with a pathogenic variant compared to 9.6% (range 1.0-88.9%) for those with a negative result (p &lt; 0.0001). The prevalence of pathogenic variants was 32.9% for women age 20-30 years, 27.5% for 31-35 years, and 16.7% for 36-40 years. Conclusions: Twenty-one percent of women with breast cancer at age 40 or younger had a pathogenic variant in a breast-cancer predisposition gene. The great majority of these pathogenic variants were found in genes (BRCA1, BRCA2, CHEK2, PALB2) for which there are validated breast cancer treatment recommendations. All women with young-onset breast cancer should be offered germline genetic testing at the time of breast cancer diagnosis to make informed surgical and medical treatment decisions.

Citation Format: Kelly Metcalfe, May Lynn Quan, Steven Narod, Ellen Warner, Christine Friedenreich, Nancy Baxter, Aletta J. Poll, Mohammad Akbari. Prevalence of Pathogenic Variants in Cancer Predisposition Genes in Women with Young Onset Breast Cancer [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 P5-03-07.

Patient and disease characteristics, treatment practices and oncologic outcomes among patients with colorectal cancer: a population-based analysis

BACKGROUND

The incidence of colorectal cancer (CRC) is increasing among young adults. We sought to report on patient and disease characteristics, treatment practice patterns and outcomes in this population.

METHODS

We conducted a retrospective cohort study using administrative health data from the Alberta Cancer Registry (2004-2015), including demographic and tumour characteristics, and treatment received. Outcome measures included overall and cancer-specific deaths. We used Cox regression and Kaplan-Meier curves to assess for factors associated with survival.

RESULTS

We included 18 070 patients with CRC (n = 1583 [8.8%] < 50 yr, n = 16 487 [91.2 %] ≥ 50 yr). Younger patients were more likely to present with locally advanced disease (21.0% v. 18.0%, p < 0.0001), stage III (16.4 % v. 14.6%, p < 0.0001) or metastatic (16.7% v. 13.8%, p < 0.0001) involvement. Younger patients were more likely to receive surgery (87.2% v. 80.9%, p < 0.0001), chemotherapy (59.6% v. 34.1%, p < 0.0001) or radiation therapy (49.5% v. 37.2%, p < 0.001). At 5 years, overall and cancer-specific survival was better among younger patients than older patients (30.6% v. 51.5% overall deaths, 27.5% v. 38.4% cancer-specific deaths, p < 0.0001).

CONCLUSION

Despite higher stage and higher grade disease, young patients with CRC had more favourable oncologic outcomes than stage-matched older patients, which may be related to younger patients receiving more aggressive treatment. Further investigation should focus on optimal treatment patterns for young patients with CRC.

Abstract B005: Investigating the effects of cancer treatment on gut microbiota in colorectal cancer patients: Study protocol

Background: Colorectal cancer (CRC) is the third most common cancer worldwide and the second leading cause of cancer mortality. Acute adverse effects (AEs) from CRC treatments (surgery, chemotherapy, radiation therapy) may cause dose limitations and/or treatment discontinuation. Chronic AEs may include bowel symptoms, fatigue, anxiety, depression, and sarcopenic obesity. These acute and chronic AEs significantly impact quality of life (QoL). A comprehensive understanding of the pathophysiological mechanism(s) driving these AEs is lacking. Evidence supports the hypothesis that the gut microbiota may be an integrative point in the pathogenesis of several AEs. Dysbiosis alters the normal function of the gut and gut-brain-axis. CRC treatments can lead to dysbiosis and in turn may drive acute and chronic AEs. Our aims are to explore how CRC treatment affects the microbiota and the further path to recovery. Methods: A prospective feasibility study of n=35 participants in Calgary, Alberta of stage I-III CRC patients to evaluate: 1) The feasibility of collecting microbiota samples at diagnosis to one-year post diagnosis; 2) Longitudinal changes to microbiota over a 1-year period; and 3) Preliminary associations between changes in the microbiota and treatment completion, treatment AEs, clinical and tumor characteristics, and changes to patient reported outcomes (PROs). Inclusion: Newly diagnosed stage I-III CRC, aged ≥18, English speaking, and willing to provide 4 fecal samples. Exclusion: Inflammatory bowel disease, hereditary CRC syndromes, or stage IV. Convenience sampling will be used. Feasibility will include recruitment and retention rates, adherence to specimen collection protocols, specimen quality, and patient satisfaction. Microbiota will be evaluated using longitudinal fecal sampling for metabolomics, culture, and mechanistic studies to examine intra-individual differences in microbiota (α and b diversity). Shotgun sequencing libraries will be prepared to generate approximately 4M 150 bp read pairs/sample. Clinical data on tumor characteristics, treatments, and treatment AEs will be abstracted from medical records. Demographic data and a battery of PROs (diet, physical activity, depression, anxiety, QoL, CRC symptoms, cognitive function, and fatigue using validated questionnaires) will be collected. Results: This study will determine the feasibility of longitudinal prospective collection of biospecimen, clinical, and PROs in newly diagnosed stage I-III CRC patients. This study will also provide preliminary data on changes to the gut microbiota as a result of treatments and how these changes may in turn impact clinical and PROs. Conclusions: This novel investigation into dysbiosis as an integrative point driving CRC treatment AEs is timely and warranted given the persistence of debilitating problems post CRC treatment. Building on data from this project we plan to conduct a population-based cohort study. Our goal is to ultimately inform interventions to manage treatment AEs, improve clinical outcomes, and improve QoL for CRC survivors.

Citation Format: Colleen Ann Cuthbert, Kathy McCoy, Anthony MacLean, Lin Yang, May Lynn Quan, Donald Buie. Investigating the effects of cancer treatment on gut microbiota in colorectal cancer patients: Study protocol [abstract]. In: Proceedings of the AACR Special Conference on Colorectal Cancer; 2022 Oct 1-4; Portland, OR. Philadelphia (PA): AACR; Cancer Res 2022;82(23 Suppl_1):Abstract nr B005.

Locoregional Management of Breast Cancer: A Chronological Review

Locoregional management of breast cancer is founded on evidence generated over a vast time period, much longer than the career span of many practicing physicians. Oncologists rely on specific patient and tumour characteristics to recommend modern-day treatments. However, some of this information may not have been available during prior periods in which the evidence was generated. For example, the comprehensive Early Breast Cancer Trialists’ Collaborative Group (EBCTCG) meta-analyses published in the 2000s typically included older trials accruing patients between the 1960s and 1980s. This raises some uncertainty about whether conclusions from studies conducted in prior eras are as relevant or applicable to modern-day patients and treatments. Reviewing the chronological order and details of the evidence can be beneficial to understanding these nuances. This review discusses the evolution of locoregional management through some key clinical trials. We aim to highlight the time period in which the evidence was generated and emphasize the 10-year outcomes for the comparability of results. Evidence supporting surgical management of the breast and axilla, as well as details of radiotherapy are discussed briefly for all stages of breast cancer.

Predictors of Sentinel Lymph Node Metastasis in Patients with Thin Melanoma: An International Multi-institutional Collaboration

BACKGROUND

Consideration of sentinel lymph node biopsy (SLNB) is recommended for patients with T1b melanomas and T1a melanomas with high-risk features; however, the proportion of patients with actionable results is low. We aimed to identify factors predicting SLNB positivity in T1 melanomas by examining a multi-institutional international population.

METHODS

Data were extracted on patients with T1 cutaneous melanoma who underwent SLNB between 2005 and 2018 at five tertiary centers in Europe and Canada. Univariable and multivariable logistic regression analyses were performed to identify predictors of SLNB positivity.

RESULTS

Overall, 676 patients were analyzed. Most patients had one or more high-risk features: Breslow thickness 0.8-1 mm in 78.1% of patients, ulceration in 8.3%, mitotic rate > 1/mm² in 42.5%, Clark's level ≥ 4 in 34.3%, lymphovascular invasion in 1.4%, nodular histology in 2.9%, and absence of tumor-infiltrating lymphocytes in 14.4%. Fifty-three patients (7.8%) had a positive SLNB. Breslow thickness and mitotic rate independently predicted SLNB positivity. The odds of positive SLNB increased by 50% for each 0.1 mm increase in thickness past 0.7 mm (95% confidence interval [CI] 1.05-2.13) and by 22% for each mitosis per mm² (95% CI 1.06-1.41). Patients who had one excised node (vs. two or more) were three times less likely to have a positive SLNB (3.6% vs. 9.6%; odds ratio 2.9 [1.3-7.7]).

CONCLUSIONS

Our international multi-institutional data confirm that Breslow thickness and mitotic rate independently predict SLNB positivity in patients with T1 melanoma. Even within this highly selected population, the number needed to diagnose is 13:1 (7.8%), indicating that more work is required to identify additional predictors of sentinel node positivity.

Validated algorithms for identifying timing of second event of oropharyngeal squamous cell carcinoma using real-world data

BACKGROUND

Understanding occurrence and timing of second events (recurrence and second primary cancer) is essential for cancer specific survival analysis. However, this information is not readily available in administrative data.

METHODS

Alberta Cancer Registry, physician claims, and other administrative data were used. Timing of second event was estimated based on our developed algorithm. For validation, the difference, in days between the algorithm estimated and the chart-reviewed timing of second event. Further, the result of Cox-regression modeling cancer-free survival was compared to chart review data.

RESULTS

Majority (74.3%) of the patients had a difference between the chart-reviewed and algorithm-estimated timing of second event falling within the 0-60 days window. Kaplan-Meier curves generated from the estimated data and chart review data were comparable with a 5-year second-event-free survival rate of 75.4% versus 72.5%.

CONCLUSION

The algorithm provided an estimated timing of second event similar to that of the chart review.

Local regional management of the axilla after positive sentinel node biopsy in breast cancer patients clinically downstaged with neoadjuvant therapy: A population-based, real-world analysis

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Background: The optimal local regional management of the positive axilla in patients who convert to clinical negative nodal status after neoadjuvant chemotherapy (NAC) remains unclear. Specifically, the benefit of completion axillary node dissection (cALND) remains in question, particularly given the associated morbidity. With results of the A11202 trial pending, we noted regional variation in the management of the axilla in this population. We therefore aimed to describe the current management of women with positive SNB after NAC, describe recurrence patterns and identify predictors of cALND in a large, population-based, real-world setting. Methods: We identified all patients who had biopsy-proven nodal disease on presentation, underwent NAC and were then clinically downstaged allowing SNB as part of their index surgery from our Synoptec provincial operative database, from January 2016 to September 2021. Pre and post NAC tumour characteristics, patient demographics, treatments and final pathology were abstracted and conveyed using descriptive statistics. Primary outcome measures were treatment with cALND and recurrence. A Cox regression model was utilized to determine predictors of both outcomes. Results: A total of 850 patients had biopsy-proven axillary disease at presentation and subsequently underwent NAC. Of these, 364 patients converted to clinically-negative node status and had a SNB, of which 175 (48%) had persistent nodal disease. Median age of this group was 50 (IQR 43-60) and 143 patients (81.7%) were treated by a high-volume breast surgeon. Most patients had clinical T1/2 tumours (73.1%) before NAC, of which 21.1% were HER2 positive, and 12.6% were triple-negative. Post NAC, 95 patients (54.3%) underwent mastectomy. A total of 39/175 patients (22.3%) underwent a cALND. Median number of sentinel nodes was 4 (IQR 3, 5); the proportion of positive sentinel nodes did not differ in those who had cALND (0.59 vs. 0.59, p = 0.95). Almost all patients (96.6%) had regional radiation. After a median of 17 months of follow-up, 33 (18.8%) SNB positive patients recurred; the majority (29 (87.9%)) had a distant recurrence, 3 (9.1%) had an isolated local breast/chest wall recurrence, and only 1 (3.0%) had an isolated regional recurrence. As far as local control, in patients with any regional recurrence, 4/7 (57.1%) had undergone cALND. Treatment site was the only significant predictor of cALND on multivariable analysis. Predictors of recurrence were low BMI, triple-negative status and clinical T3/4 disease before NAC. Conclusions: The lack of definitive data for patients with persistent pathologic nodal disease after NAC has led to variable practice patterns, with lower than expected rates of cALND. Within our cohort, there was not a significant association between omission of cALND and regional recurrence.

Breast cancer after reduction mammoplasty: A population-based analysis of incidence, treatment, and screening patterns

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Background: The incidence of breast cancer after reduction mammoplasty has been demonstrated to be lower than the general population in several large registry trials performed in primarily European populations; North American data is lacking. Tissue rearrangement during reduction mammoplasty may lead to abnormal breast imaging results postoperatively resulting in more challenging screening.The purpose of this study was to describe the incidence and treatment of breast cancer after reduction mammoplasty in a more contemporary Canadian population, and to better understand the use of breast cancer screening modalities in these patients. Methods: This population-based retrospective analysis utilized the Discharge Abstract Database held by the Canadian Institute for Health Information (CIHI) and the National Ambulatory Care Reporting System (NACRS) to identify all women 20 or older who underwent reduction mammoplasty in Alberta, Canada between 2003 and 2007. The incidence and treatment of breast cancer was compared among patients who underwent reduction mammoplasty and age-sex matched controls in Alberta. Imaging utilization post mammoplasty, including use of mammography, ultrasound and breast biopsy was also compared between these two groups. Results: A total of 8,021 patients over 20 years old underwent reduction mammoplasty during the study period. Patients were followed for an average of 12.6 years. Most women (6,417, 80%) underwent reduction mammoplasty surgery between the ages of 20-50. Compared to controls, women who underwent reduction mammoplasty had more comorbidities (Charlson Comorbidities > 1: 5.2% vs 4.2% controls, p < 0.0001). Overall, 89 (1.1%) patients who underwent reduction mammoplasty developed breast cancer after surgery, compared to 453 (1.9%) controls (p < 0.0001). Among patients diagnosed with breast cancer, there was no difference in patient characteristics, tumor size, histology and grade between the two groups. Fewer patients presented with metastatic disease after reduction mammoplasty (0% vs 5.1%, p = 0.043). The surgical treatment differed between groups; patients who underwent reduction mammoplasty were significantly more likely to undergo mastectomy for breast cancer (41.6% vs 1.5%, p < 0.0001). Women who underwent reduction were more likely to undergo mammography (66.7% vs 58.7%, p < 0.001), ultrasound (29.2% vs 26.2%, p < 0.0001) and biopsy for benign disease (7.2% vs 6%, p = 0.0001) compared to controls. Conclusions: Despite an increased frequency of breast cancer screening, the incidence of breast cancer is lower after reduction mammoplasty compared to women who did not undergo breast reduction. After a diagnosis of breast cancer, surgical treatment patterns differ between groups despite similarities in tumor characteristics, whereby mastectomy is more common in those who have undergone breast reduction.

New method for determining breast cancer recurrence-free survival using routinely collected real-world health data

Background

In cancer survival analyses using population-based data, researchers face the challenge of ascertaining the timing of recurrence. We previously developed algorithms to identify recurrence of breast cancer. This is a follow-up study to detect the timing of recurrence.

Methods

Health events that signified recurrence and timing were obtained from routinely collected administrative data. The timing of recurrence was estimated by finding the timing of key indicator events using three different algorithms, respectively. For validation, we compared algorithm-estimated timing of recurrence with that obtained from chart-reviewed data. We further compared the results of cox regressions models (modeling recurrence-free survival) based on the algorithms versus chart review.

Results

In total, 598 breast cancer patients were included. 121 (20.2%) had recurrence after a median follow-up of 4 years. Based on the high accuracy algorithm for identifying the presence of recurrence (with 94.2% sensitivity and 79.2% positive predictive value), the majority (64.5%) of the algorithm-estimated recurrence dates fell within 3 months of the corresponding chart review determined recurrence dates. The algorithm estimated and chart-reviewed data generated Kaplan–Meier (K-M) curves and Cox regression results for recurrence-free survival (hazard ratios and P-values) were very similar.

Conclusion

The proposed algorithms for identifying the timing of breast cancer recurrence achieved similar results to the chart review data and were potentially useful in survival analysis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09333-6.

Abstract P2-01-02: A whole blood assay to identify breast cancer: Interim analysis of the international identify breast cancer (IDBC) study evidence supporting the Syantra DX breast cancer test

Background: Breast cancer is often detected at later stages, indicating a significant need for additional screening methods. Mammography has limitations in breast cancer detection, for example young age, mammographic high density (categories C and D), small tumors and breast cancer classifications such as invasive lobular carcinomas. Syantra DX Breast Cancer is a new whole blood test that detects the presence of breast cancer by evaluating the expression of 12 novel genes through a custom qPCR process with proprietary software that includes machine learning-derived algorithms. Methodology: Whole blood samples (2.5 ml) were collected and analyzed with Syantra DX Breast Cancer as part of the ongoing IDBC prospective international clinical study (NCT04495244). The study is designed to demonstrate test performance in 2,100 participants. Women aged 30 to 75 years with a normal screening mammogram or physical exam (for the controls), or a BI-RADs 3 – 5 score on a screening mammogram were enrolled. A total of 1,107 participants (240 asymptomatic breast cancer, 867 non-cancer) were recruited and evaluated. All blood samples were collected pre-biopsy. For this interim analysis, 383 samples (132 cancer, 251 non-cancer) were used for machine learning-based model development and initial testing using a cross-validation approach. A set of 724 samples, with 695 evaluable samples (blind test set: 96 cancer, 599 non-cancer) were used for independent testing. All samples in the test set were randomized and blinded by the Alberta Cancer Research Biobank. Clinical performance metrics are reported for the blind test set with 99.5% confidence intervals (CI) computed through an exact binomial test. Results: In the blind test set, 59% of breast cancer subjects were Stage 1 and 25% stage 2. For molecular subtype, 75% were hormone receptor positive, 10% were HER2 positive, and 5% were triple negative. For subjects with invasive breast cancer, the average tumor size was 29 mm (CI: 19 – 38 mm). For the entire test set, Syantra DX Breast Cancer demonstrated an inferred accuracy of 92.2% (CI: 88.9% – 94.6%) with a specificity of 94.3% (CI: 91.0% – 96.4%) and sensitivity of 79.2% (CI: 65.5% – 88.4%) for cancer detection (Table 1). Higher performance was observed in the group of study women under 50 with an inferred specificity of 99.0% and a sensitivity of 91.7% (Table 1). Evaluation of performance in women with extremely dense breast tissue (category D; n=52) revealed an inferred specificity of 95.3% (CI: 77.4% – 99.2%) and sensitivity of 88.9% (CI: 42.6% – 98.9%). This analysis also showed that small tumors less than 10 mm (n=19) were detected by the test, with a sensitivity of 68.4%. Conclusions: Interim data from the IDBC study demonstrated the clinical utility of the Syantra DX Breast Cancer test for use in early screening. Syantra DX Breast Cancer is the first blood test to show strong performance for women under 50, as well for those with very high breast density, and therefore provides a promising screening option to supplement current imaging approaches.

Table 1. Performance Metrics of the Syantra DX Breast Cancer TestAgeNumber of participants (n)AccuracySpecificitySensitivity&lt; 50Normal: 19298.5% (CI: 93.8% – 99.7%)99.0% (CI: 94.2% – 99.8%)91.7% (CI: 51.1% – 99.1%)Cancer: 12≥ 50Normal: 40789.6% (CI: 85.1% – 92.9%)92.1% (CI: 87.5% – 95.1%)77.4% (CI: 62.5% – 87.5%)Cancer: 84Entire cohortNormal: 59992.2% (CI: 88.9% – 94.6%)94.3% (CI: 91.0% – 96.4%)79.2% (CI: 65.5% – 88.4%)Cancer: 96

Citation Format: Nigel Bundred, Kenneth Fuh, Nasimeh Asgarian, Shannon Brown, Danielle Simonot, Xiuling Wang, Robert Shepherd, May Lynn Quan, Bobbi Jo Docktor, Anthony Maxwell, Cliona Kirwan, Alan Hollingsworth (retired), Donald Morris, Kristina Rinker. A whole blood assay to identify breast cancer: Interim analysis of the international identify breast cancer (IDBC) study evidence supporting the Syantra DX breast cancer test [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P2-01-02.

Developing a Prediction Model for Pathologic Complete Response Following Neoadjuvant Chemotherapy in Breast Cancer: A Comparison of Model Building Approaches

The optimal characteristics among patients with breast cancer to recommend neoadjuvant chemotherapy is an active area of clinical research. We developed and compared several approaches to developing prediction models for pathologic complete response (pCR) among patients with breast cancer in Alberta.

Associations Between Physician Prescribing Behavior and Persistent Postoperative Opioid Use Among Cancer Patients Undergoing Curative-intent Surgery: A Population-based Cohort Study

OBJECTIVE

This study aimed to evaluate the association between prescribers' opioid prescribing history and persistent postoperative opioid use in cancer patients undergoing curative-intent surgery.

BACKGROUND

Study has shown that patients may be over-prescribed analgesics after surgery. However, whether and how the prescriber's opioid prescribing behavior impacts persistent opioid use is unclear.

METHODS

All adults with a diagnosis of solid cancers who underwent surgery during the study period (2009-2015) in Alberta, Canada and were opioid-naïve were included. The key exposure was the historical opioid-prescribing pattern of a patient's most responsible prescriber. The primary outcome was "new persistent postoperative opioid user," was defined as a patient who was opioid-naïve before surgery and subsequently filled at least 1 opioid prescription between 60 and 180 days after surgery.

RESULTS

We identified 24,500 patients. Of these, 2106 (8.6%) patients became a new persistent opioid user after surgery. Multivariate analysis demonstrated that patients with most responsible prescribers that historically prescribed higher daily doses of opioids (≥50 vs <50 mg oral morphine equivalent) had an increased risk of new persistent opioid use after surgery (odds ratio = 2.41, P < 0.0001). In addition to the provider's prescribing pattern, other factors including younger age, comorbidities, presurgical opioid use, chemotherapy, type of tumor/surgical procedure were also found to be independently associated with new persistent postoperative opioid use.

CONCLUSIONS

Our results suggest that prescriber with a history of prescribing a higher opioid dose is an important predictor of persistent postoperative opioid use among cancer patients undergoing curative-intent surgery.

Associations Between the Density of Oil and Gas Infrastructure and the Incidence, Stage and Outcomes of Solid Tumours: A Population-Based Geographic Analysis

Background

We hypothesized that there are geographic areas of increased cancer incidence in Alberta, and that these are associated with high densities of oil and gas(O+G) infrastructure. Our objective was to describe the relationship between O+G infrastructure and incidence of solid tumours on a population level.

Methods

We analyzed all patients >=18 years old with urological, breast, upper GI, colorectal, head and neck, hepatobiliary, lung, melanoma, and prostate cancers identified from the Alberta Cancer Registry from 2004-2016. Locations of active and orphan O+G sites were obtained from the Alberta Energy Regulator and Orphan Well Association. Orphan sites have no entity responsible for their maintenance. ArcGIS (ESRI, Toronto, Ontario) was used to calculate the distribution of O+G sites in each census distribution area (DA). Patient residence at diagnosis was defined by postal code. Incidence of cancer per DA was calculated and standardized. Negative binomial regression was done on O+G site density as a categorical variable with cutoffs of 1 and 30 wells/100km², compared to areas with 0 sites.

Results

125,316 patients were identified in the study timeframe;58,243 (46.5%) were female, mean age 65.6 years. Breast (22%) and prostate (19.8%) cancers were most common. Mortality was 36.5% after a median of 30 months follow up (IQR 8.4 - 68.4). For categorical density of active O+G sites, RR was 1.02 for 1-30 sites/100km² (95% CI=0.95-1.11) and 1.15 for >30 sites/100km2 (p<0.0001, 95%CI=1.11-1.2). For orphan sites, 1-30 sites RR was 1.25 (p<0.0001, 95%CI=1.16-1.36) and 1.01 (p=0.97, 95%CI=0.7-1.45) for >30 sites. For all O+G sites, RR for 1-30 sites was 1.03 (p=0.4328, 95%CI=0.95-1.11) and 1.15 (p<0.0001, 95%CI=1.11-1.2) for >30 sites.

Conclusion

We report a statistically significant correlation between O+G infrastructure density and solid tumour incidence in Alberta. To our knowledge this is the first population-level study to observe that active and orphan O+G sites are associated with increased risk of solid tumours. This finding may inform policy on remediation and cancer prevention.

Acute Care Use by Breast Cancer Patients on Adjuvant Chemotherapy in Alberta: Demonstrating the Importance of Measurement to Improving Quality

Breast cancer patients receiving adjuvant chemotherapy are at increased risk of acute care use. The incidence of emergency department (ED) visits and hospitalizations (H) have been characterized in other provinces but never in Alberta. We conducted a retrospective population-based cohort study using administrative data of women with stage I-III breast cancer receiving adjuvant chemotherapy. Rates of ED and H use in the 180 days following chemotherapy initiation were determined, and logistic regression was performed to identify risk factors. We found that 47% of women receiving adjuvant chemotherapy experienced ED or H, which compared favourably to other provinces. However, Alberta had the highest rate of febrile neutropenia-related ED visits, and among the highest chemotherapy-related ED visits. The incidence of acute care use increased over time, and there were significant institutional differences despite operating under a single provincial healthcare system. Our study demonstrates the need for systematic measurement and the importance of quality improvement programs to address this gap.

Examining social media peer support and improving psychosocial outcomes for young women with breast cancer

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Background: Young women with breast cancer (YWBC) have unique survivorship needs due to life stage at point of diagnosis. Peer support sought by YWBC through social media channels appears to be rising. We aimed to understand the unmet needs of YWBC in order to develop a tailored peer support program to improve young women’s breast cancer experience and ultimately reduce psychosocial morbidity long-term. Methods: Using qualitative inquiry, we conducted semi-structured interviews with YWBC survivors and clinicians using purposive sampling. Inclusion criteria were women aged 40 years or younger at diagnosis, stage 0-IV disease. Survivors were minimum one year post-diagnosis and with active treatment complete. Interviews were recorded and transcribed verbatim and data was analyzed using Thorne’s Interpretive Description. Themes were reviewed with study team throughout data analysis. Results: Thirty-six participants were interviewed from ten centers across seven Canadian provinces; mean age 36 years. Participant reported demographics:18% ‘visible minority’, 9% ‘born outside Canada’, 7% ‘Indigenous’ and 54% of patients’ household income at or below Canadian average. At point of diagnosis 69% married, 44% had children and 9% pregnant or postpartum. Themes from YWBC interviewed focused on coping needs: feeling alone, misunderstood by professionals and misplaced among peers. Participants described all-age peer support groups risked triggering anxieties, lacked convenience and were comprised of women at later life stages with differing needs. YWBC reported lack of young age breast cancer-specific peer support. YWBC frequently found support through social media de novo, by following young-age breast cancer survivor pages, blogs and forums as well as virtual support groups. YWBC also report benefit from identifying similar life and cancer stage survivors globally and forming individual relations virtually, through direct messaging. Additionally, benefits described from age-specific social media support included unique shared experience and understanding, hope from positive outcomes of similar life stage diagnoses, and increased confidence and healthcare navigation for YWBC. Women unanimously requested one on one peer support program development - a survivor mentorship scheme specifically for YWBC that would provide the convenience of online support without the obligations or emotionally overwhelming nature of structured support groups. Conclusions: We have identified unique support needs from this young cohort of women that are not currently being met within standard Canadian healthcare pathways. We aim to develop a novel one on one peer support program for YWBC, to optimize psychosocial support and improve young women’s empowerment and autonomy in managing the effects of cancer long-term.

Higher-risk breast cancer in women aged 80 and older: Exploring the effect of treatment on survival

Background

To understand the association between various treatments and survival for older women with higher-risk breast cancer when controlling for patient and tumor factors.

Materials and methods

We conducted a retrospective, population-based study. Women aged 80 years or older and diagnosed between 2004 and 2017 with non-metastatic, higher-risk breast cancer were identified form the provincial cancer registry in Alberta, Canada. Higher-risk was defined as any of following: T3/4, node positive, human epidermal factor receptor-2 (Her2) positive or triple negative disease. Treatments were surgery, radiotherapy and systemic therapy (hormonal therapy, and/or chemotherapy and/or trastuzumab) or a combination of the previous. Cox regression models were used to examine the association between treatments and breast cancer specific survival (BCSS) and overall survival (OS).

Results

1369 patients were included. The median age was 84 years. 332 (24%) of women had T3-T4 tumors, 792 (58%) had nodal involvement, 130 (10%) had Her2 positive tumors, 124 (9%) had triple negative tumors. After a median follow-up of 35 months, 29.5% of patients died of breast cancer whereas 34.2% died from other causes. Patients had a lower adjusted hazard for BCSS if they had surgery (hazard ratio [HR] = 0.37 95% confidence interval [CI]: 0.27, 0.51), or systemic therapy (HR = 0.75, 95%CI: 0.58, 0.98). Patients had an increased probability of breast cancer death in the first 5 years after diagnosis compared to death from other causes.

Conclusions

Surgery and systemic therapy were associated with longer BCSS and OS. This suggests that maximizing treatments might benefit higher-risk patients.

•

Breast cancer patients aged 80 or older are rarely represented in clinical trials.

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Association between survival and treatment is unknown for higher-risk patients.

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Breast cancer death affected around one-third of the higher-risk population.

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Surgery and systemic therapy were associated with lower breast cancer death.

Examining the etiology of early-onset breast cancer in the Canadian Partnership for Tomorrow's Health (CanPath)

PURPOSE

Breast cancer incidence among younger women (under age 50) has increased over the past 25 years, yet little is known about the etiology among this age group. The objective of this study was to investigate relationships between modifiable and non-modifiable risk factors and early-onset breast cancer among three prospective Canadian cohorts.

METHODS

A matched case-control study was conducted using data from Alberta's Tomorrow Project, BC Generations Project, and the Ontario Health Study. Participants diagnosed with breast cancer before age 50 were identified through provincial registries and matched to three control participants of similar age and follow-up. Conditional logistic regression was used to examine the association between factors and risk of early-onset breast cancer.

RESULTS

In total, 609 cases and 1,827 controls were included. A body mass index ≥ 30 kg/m² was associated with a lower risk of early-onset breast cancer (OR 0.65; 95% CI 0.47-0.90), while a waist circumference ≥ 88 cm was associated with an increased risk (OR 1.58; 95% CI 1.18-2.11). A reduced risk was found for women with ≥ 2 pregnancies (OR 0.76; 95% CI 0.59-0.99) and a first-degree family history of breast cancer was associated with an increased risk (OR 1.95; 95% CI 1.47-2.57).

CONCLUSIONS

In this study, measures of adiposity, pregnancy history, and familial history of breast cancer are important risk factors for early-onset breast cancer. Evidence was insufficient to conclude if smoking, alcohol intake, fruit and vegetable consumption, and physical activity are meaningful risk factors. The results of this study could inform targeted primary and secondary prevention for early-onset breast cancer.

Health outcomes and resource utilization associated with postsurgical opioid use among cancer patients undergoing curative-intent surgery

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Background: To date, it remains unclear whether new persistent post-surgical opioid use is associated with subsequent opioid overdose, higher mortality and greater consumption of healthcare resources among cancer patients. To fill this gap, a population-based cohort study by applying real-world data has been performed to compare the long-term outcomes and healthcare resource use between new persistent and non-persistent opioid users among cancer patients after curative-intent surgery. Methods: This retrospective cohort study included all adult cancer patients with solid tumours who received curative-intent surgery in Alberta between 2011 and 2015, with a follow-up period until December 31, 2019. Patients who had multiple tumors, or had a follow-up < 6 months, or > 30 days of hospitalization were excluded. A new persistent post-surgical opioid user was defined as a patient who was opioid-naïve before surgery (no opioid prescription filled prior to the surgery) and subsequently filled at least one opioid prescription between 60 and 180 days after surgery. The outcomes (opioid overdose and mortality within 3 years) and health resource use (emergency department visits and hospitalization within the first year) after surgery were evaluated by applying multivariable logistic and Cox regressions. Results: A total of 19,219 patients received curative-intent surgery with a median follow-up of 47 months, of which 1,530 (8.0%) were identified as postoperative new persistent opioid users. Compared with the non-persistent group, a higher rate of opioid overdose (OR = 1.81, 95% CI: 1.49-2.2) within 3 years of surgery has been observed for new persistent opioid users, who were also associated with a greater likelihood of being hospitalized (OR = 2.52, 95% CI: 2.21-2.87) and visiting an emergency room (OR = 2.0, 95% CI: 1.78-2.24) within the first year after surgery. A higher overall (HR = 1.37, 95% CI: 1.2-1.57) and non-cancer caused mortality (HR = 1.39, 95% CI: 1.18-1.65) has also been detected for new persistent opioid users during the study follow-up period. Conclusions: For cancer patients undergoing curative-intent surgery, reducing new persistent opioid use is imperative to improve subsequent outcomes and health resource utilization.

Geospatial access predicts cancer stage at presentation and outcomes for patients with breast cancer in southwest Nigeria: A population-based study

BACKGROUND

The majority of women in Nigeria present with advanced-stage breast cancer. To address the role of geospatial access, we constructed a geographic information-system-based model to evaluate the relationship between modeled travel time, stage at presentation, and overall survival among patients with breast cancer in Nigeria.

METHODS

Consecutive patients were identified from a single-institution, prospective breast cancer database (May 2009-January 2019). Patients were geographically located, and travel time to the hospital was generated using a cost-distance model that utilized open-source data. The relationships between travel time, stage at presentation, and overall survival were evaluated with logistic regression and survival analyses. Models were adjusted for age, level of education, and socioeconomic status.

RESULTS

From 635 patients, 609 were successfully geographically located. The median age of the cohort was 49 years (interquartile range [IQR], 40-58 years); 84% presented with ≥stage III disease. Overall, 46.5% underwent surgery; 70.8% received systemic chemotherapy. The median estimated travel time for the cohort was 45 minutes (IQR, 7.9-79.3 minutes). Patients in the highest travel-time quintile had a 2.8-fold increase in the odds of presenting with stage III or IV disease relative to patients in the lowest travel-time quintile (P = .006). Travel time ≥30 minutes was associated with an increased risk of death (HR, 1.65; P = .004).

CONCLUSIONS

Geospatial access to a tertiary care facility is independently associated with stage at presentation and overall survival among patients with breast cancer in Nigeria. Addressing disparities in access will be essential to ensure the development of an equitable health policy.

Investigating factors associated with postmastectomy emergency department visits: A population-based analysis

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Background: In 2016, a multi-pronged pathway was implemented in 13 hospitals across the province of Alberta, Canada to improve the mastectomy perioperative care experience focused on two objectives: 1) to increase same day surgery mastectomy rates and 2) decrease the number of unnecessary postoperative ED visits. The pathway successfully increased same day mastectomy rates from 1.7% to 47.8%, however the rate of postoperative ED visits remained high at 22-27%, a rate several-fold greater than described at other centers (3.1-12.8%) in spite of focused interventions at the patient and provider level to enhance perioperative support. Objective: To investigate potential factors associated with high postoperative ED visits following mastectomies in Alberta, Canada. Methods: Data was collected using the Discharge Abstract Database, and the National Ambulatory Care Reporting System database. Eligible patients included all women over 18 years old who underwent a mastectomy in the province of Alberta between 2004 and 2018. Patient demographics and operative variables including age, SES, Charlson comorbidities, date of surgery, surgery type (same-day vs. overnight) and health regions were collected. Primary outcome of interest was an ED visit within 30 days of mastectomy. Univariate and multivariate analyses were performed to identify independent predictors for post-operative ED visits. Results: A total of 18,076 patients had mastectomy during the study period, of which 4219 (23.3%) had an ED visit within 30 days of surgery. The most common causes of ED visits were infection, pain, and nausea/vomiting. Independent factors associated with ED visits were increasing age, overnight stay mastectomy, having reconstruction, cerebrovascular disease, chronic pulmonary disease, peptic ulcer disease, diabetes, depression, and living rurally. There was a slight decrease in ED visits post-implementation of the perioperative pathway (21.6% vs. 23.7%) but it was not statistically significant in the multivariable analysis. Conclusions: Post-operative ED visits remain high despite initiating a province-wide surgical pathway in 2016 which emphasizes patient education and improved perioperative care and supports. ED visits are associated with geographic location, specific comorbidities, and overnight stays. Currently, the majority of ED visits are manageable in non-emergent settings. Further investigations are necessary to discern whether additional perioperative interventions can curb the high ED visit rate.

Nodal staging affects adjuvant treatment choices in elderly patients with clinically node-negative, estrogen receptor-positive breast cancer

Background

In response to Choosing Wisely recommendations that sentinel lymph node biopsy (slnb) should not be routinely performed in elderly patients with node-negative (cN0), estrogen receptor-positive (er+) breast cancer, we sought to evaluate how nodal staging affects adjuvant treatment in this population.

Methods

From a prospective database, we identified patients 70 or more years of age with cN0 breast cancer treated with surgery for er+ her2-negative invasive disease during 2012-2016. We determined rates of, and factors associated with, nodal positivity (pN+), and compared the use of adjuvant radiation (rt) and systemic therapy by nodal status.

Results

Of 364 patients who met the inclusion criteria, 331 (91%) underwent slnb, with 75 (23%) being pN+. Axillary node dissection was performed in 11 patients (3%). On multivariate analysis, tumour size was the only factor associated with pN+ (p = 0.007). Nodal positivity rates were 0%, 13%, 23%, 33%, and 27% for lesions preoperatively sized at 0-0.5 cm, 0.5-1 cm, 1.1-2.0 cm, 2.1-5.0 cm, and more than 5.0 cm. Compared with patients assessed as node-negative, those who were pN+ were more likely to receive axillary rt (lumpectomy: 53% vs. 1%, p < 0.001; mastectomy: 43% vs. 2%, p < 0.001), and adjuvant systemic therapy (endocrine: 82% vs. 69%; chemotherapy plus endocrine: 7% vs. 2%, p = 0.002).

Conclusions

Of elderly patients with cN0 er+ breast cancer, 23% were pN+ on slnb. Size was the primary predictor of nodal status, and yet significant rates of nodal positivity were observed even in tumours preoperatively sized at 1 cm or less. The use of rt and systemic adjuvant therapies differed by nodal status, although the long-term oncologic implications require further investigation. Multidisciplinary input on a case-by-case basis should be considered before omission of slnb.

A pan-Canadian prospective study of young women with breast cancer: the rationale and protocol design for the RUBY study

Introduction

The understanding of the biology and epidemiology of, and the optimal therapeutic strategies for, breast cancer (bca) in younger women is limited. We present the rationale, design, and initial recruitment of Reducing the Burden of Breast Cancer in Young Women (ruby), a unique national prospective cohort study designed to examine the diagnosis, treatment, quality of life, and outcomes from the time of diagnosis for young women with bca.

Methods

Over a 4-year period at 33 sites across Canada, the ruby study will use a local and virtual recruitment model to enrol 1200 women with bca who are 40 years of age or younger at the time of diagnosis, before initiation of any treatment. At a minimum, comprehensive patient, tumour, and treatment data will be collected to evaluate recurrence and survival. Patients may opt to complete patient-reported questionnaires, to provide blood and tumour samples, and to be contacted for future research, forming the core dataset from which 4 subprojects evaluating genetics, lifestyle factors, fertility, and local management or delivery of care will be performed.

Summary

The ruby study will be the most comprehensive repository of data, biospecimens, and patient-reported outcomes ever collected with respect to young women with bca from the time of diagnosis, enabling research unique to that population now and into the future. This research model could be used for other oncology settings in Canada.

Identifying opportunities to support patient-centred care for ductal carcinoma in situ: qualitative interviews with clinicians

Background

Women with ductal carcinoma in situ (DCIS) report poor patient-clinician communication, and long-lasting confusion and anxiety about their treatment and prognosis. Research shows that patient-centred care (PCC) improves patient experience and outcomes. Little is known about the clinician experience of delivering PCC for DCIS. This study characterized communication challenges faced by clinicians, and interventions they need to improve PCC for DCIS.

Methods

Purposive and snowball sampling were used to recruit Canadian clinicians by specialty, gender, years of experience, setting, and geographic location. Qualitative interviews were conducted by telephone. Data were analyzed using constant comparison. Findings were mapped to a cancer-specific, comprehensive PCC framework to identify opportunities for improvement.

Results

Clinicians described approaches they used to address the PCC domains of fostering a healing relationship, exchanging information, and addressing emotions, but do not appear to be addressing the domains of managing uncertainty, involving women in making decisions, or enabling self-management. However, many clinicians described challenges or variable practices for all PCC domains but fostering a healing relationship. Clinicians vary in describing DCIS as cancer based on personal beliefs. When exchanging information, most find it difficult to justify treatment while assuring women of a good prognosis, and feel frustrated when women remain confused despite their efforts to explain it. While they recognize confusion and anxiety among women, clinicians said that patient navigators, social workers, support groups and high-quality information specific to DCIS are lacking. Despite these challenges, clinicians said they did not need or want communication interventions.

Conclusions

Findings represent currently unmet opportunities by which to help clinicians enhance PCC for DCIS, and underscore the need for supplemental information and supportive care specific to DCIS. Future research is needed to develop and test communication interventions that improve PCC for DCIS. If effective and widely implemented, this may contribute to improved care experiences and outcomes for women diagnosed with and treated for DCIS.

Mutational landscape differences between young-onset and older-onset breast cancer patients

Background

The incidence of breast cancer among young women (aged ≤40 years) has increased in North America and Europe. Fewer than 10% of cases among young women are attributable to inherited BRCA1 or BRCA2 mutations, suggesting an important role for somatic mutations. This study investigated genomic differences between young- and older-onset breast tumours.

Methods

In this study we characterized the mutational landscape of 89 young-onset breast tumours (≤40 years) and examined differences with 949 older-onset tumours (> 40 years) using data from The Cancer Genome Atlas. We examined mutated genes, mutational load, and types of mutations. We used complementary R packages “deconstructSigs” and “SomaticSignatures” to extract mutational signatures. A recursively partitioned mixture model was used to identify whether combinations of mutational signatures were related to age of onset.

Results

Older patients had a higher proportion of mutations in PIK3CA, CDH1, and MAP3K1 genes, while young-onset patients had a higher proportion of mutations in GATA3 and CTNNB1. Mutational load was lower for young-onset tumours, and a higher proportion of these mutations were C > A mutations, but a lower proportion were C > T mutations compared to older-onset tumours. The most common mutational signatures identified in both age groups were signatures 1 and 3 from the COSMIC database. Signatures resembling COSMIC signatures 2 and 13 were observed among both age groups. We identified a class of tumours with a unique combination of signatures that may be associated with young age of onset.

Conclusions

The results of this exploratory study provide some evidence that the mutational landscape and mutational signatures among young-onset breast cancer are different from those of older-onset patients. The characterization of young-onset tumours could provide clues to their etiology which may inform future prevention. Further studies are required to confirm our findings.

The incidence of breast cancer in Canada 1971-2015: trends in screening-eligible and young-onset age groups

OBJECTIVES

Breast cancer incidence has fluctuated considerably in Canada, with recent reductions in rates among screening-eligible women. However, incidence of early-onset and pre-menopausal breast cancer is understudied. We examined age-specific trends in breast cancer incidence between 1971 and 2015, as well as possible trends by birth cohort.

METHODS

Incidence data were collected from the National Cancer Incidence Reporting System and the Canadian Cancer Registry, and annual percent changes were estimated using the Joinpoint Regression Program. Five-year birth cohort models were fit using the National Cancer Institute's web tool.

RESULTS

Breast cancer incidence among women under age 40 has increased since 2000, while incidence under 50 has remained stable. Rates of post-menopausal breast cancer declined sharply and have recently plateaued. More recent birth cohorts are at a non-significantly increased risk of breast cancer compared with the reference, with an increasing upward trend.

CONCLUSIONS

Rates of breast cancer may be increasing among younger women, and there is suggestive evidence that more recent birth cohorts are at increased risk of the disease. More research is needed into the risk factors for pre-menopausal breast cancer to support primary prevention efforts in this area.

Breast Biopsy During Post-treatment Surveillance of Screen-Detected Breast Cancer Patients Yields High Rates of Benign Findings

BACKGROUND

The incidence of breast biopsy following treatment for breast cancer is not well-characterized. We sought to determine the frequency and outcomes of breast biopsy and the need for subsequent surgery in patients treated with breast-conserving surgery (BCS).

METHODS

Using a prospective database, we identified patients in Alberta, Canada, treated with BCS for screen-detected breast cancer or ductal carcinoma in situ (DCIS) from 2010 to 2014. Post-treatment breast procedures were identified from physician claims data. Multivariable analysis was performed to identify factors associated with biopsy.

RESULTS

We included 2065 patients with a median of 6.4 years of follow-up; most had DCIS (n = 426, 20.6%) or stage I disease (n = 1385, 67.1%). Post-treatment core biopsy was performed in 389 (18.8%, 95% confidence interval [CI] 17.2-20.6%) patients, and excisional biopsy was performed in 19 (0.9%, 95% CI 0.6-1.4%) patients. The per-patient benign-to-malignant biopsy ratio was 3.2 to 1, and the overall malignancy rate was 6.1% (95% CI 5.1-7.2%). Younger age, proximity to a cancer center, positive margins, and the use of magnetic resonance imaging were associated with biopsy (p < 0.05). Additional surgery was performed in 150 (7.3%, 95% CI 6.2-8.5%) patients; 93 (4.5%, 95% CI 3.6-5.4%) patients underwent mastectomy. Surgery was performed for local recurrence/ipsilateral cancer in 62 (3.0%) patients, contralateral breast cancer in 60 (2.9%) patients, bilateral breast cancer in 3 (0.1%) patients, and benign indications/prophylaxis in 25 (1.2%) patients.

CONCLUSIONS

One in five patients required breast biopsy during post-treatment surveillance following BCS and most revealed benign findings. Rates of additional surgery, especially subsequent mastectomy due to ipsilateral or contralateral malignancy, were low. Patients can be reassured of these findings during pre-treatment counseling and post-treatment surveillance.

Neoadjuvant radiotherapy followed by surgery compared with surgery alone in the treatment of retroperitoneal sarcoma: a population-based comparison

Introduction

Retroperitoneal sarcoma (rps) encompasses a heterogeneous group of malignancies with a high recurrence rate after resection. Neoadjuvant radiotherapy (nrt) is often used in the hope of sterilizing margins and decreasing local recurrence after excision. We set out to compare local recurrence-free survival (lrfs) and overall survival (os) in patients treated with or without nrt before resection.

Methods

Patients diagnosed with rps from February 1990 to October 2014 were identified in the Alberta Cancer Registry. Patients with complete gross resection of rps and no distant disease were included. Patient, tumour, treatment, and outcomes data were abstracted in a primary chart review. Baseline characteristics were compared using the Wilcoxon nonparametric test for continuous data and the Fisher exact test for dichotomous and categorical data. Survival was analyzed using Kaplan-Meier curves with log-rank test. Cox regression was performed to control for age, sex, tumour size, tumour grade, date of diagnosis, multivisceral resection, and intraoperative rupture.

Results

Resection alone was performed in 62 patients, and resection after nrt, in 40. Use of nrt was associated with multivisceral resection and negative microscopic margins. On univariate analysis, nrt was associated with superior median lrfs (89.3 months vs. 28.4 months, p = 0.04) and os (119.4 months vs. 75.9 months, p = 0.04). On multivariate analysis, nrt, younger age, and lower tumour grade predicted improved lrfs and os; sex, tumour size, date of diagnosis, multivisceral resection, and tumour rupture did not.

Conclusions

In this population-based study, nrt was associated with superior lrfs and os on both univariate and multivariate analysis. When feasible, nrt should be considered until a randomized controlled trial is completed.

Evaluating A Multidisciplinary Cancer Conference Checklist: Practice Versus Perceptions

Background

Presentation to multidisciplinary cancer conferences (MCCs) supports optimal treatment of young women with breast cancer (YWBC). However, research shows barriers to MCC practice, and variation in professional attendance and referral patterns. A checklist may help overcome these barriers and support MCC practice with YWBC.

Methods

We developed, piloted and evaluated an MCC checklist in sites participating in a pan-Canadian study (RUBY; Reducing the bUrden of Breast cancer in Young women). A survey assessed checklist processes and impacts, and checklist data were analysed for checklist uptake, MCC presentation rates and MCC processes including staff attendance.

Results

Fifteen RUBY sites used the checklist (~50%), mostly for data collection/tracking. Some positive effects on clinical practice such as increased presentation of YWBC at MCC were reported, but most survey participants indicated that MCC processes were sufficient without the checklist. Conversely, checklist data show that only 31% of patients were presented at MCC. Of those, 41% were recommended treatment change.

Conclusion

Despite limited checklist uptake, there was evidence of its clinical practice benefit. Furthermore, it supported data collection/quality monitoring. Critically, checklist data showed gaps in MCC practice and low MCC presentation rates for YWBC. This contrasts with overall provider perceptions that MCCs are working well. Findings suggest that supports for MCC are needed but may best take the form of clear national practice recommendations and audit and feedback cycles to inform awareness of good MCC practice and outcomes. In this setting, tools like the MCC checklist may become helpful in supporting MCC practice.

Barriers to fertility preservation (FP) in a prospective pan-Canadian study of young women with breast cancer (YWBC)

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Background: Despite ASCO recommendations that oncologists routinely offer FP to young cancer patients prior to treatment, studies show that only a minority of YWBC are given this option. We sought to determine whether an intervention, including educational materials and regular reminders to breast surgeons, would improve FP referral. The current report examines the rates of FP discussion, referral, uptake and reasons for declining, according to participants’ self-reported pre-diagnosis fertility plans. Methods: Consecutive women ≤ age 40 newly diagnosed with breast cancer at 30 Canadian sites were offered enrolment in a national study of YWBC. At 3 months each participant was surveyed regarding her pre-diagnosis (dx) fertility plans and post-dx oncofertility management. Results: Of the 712 recruits (09/15 to 08/18) with invasive disease (mean age 36), 46%, 15% and 29% had 0, 1 or 2 children respectively and 77% were in a stable relationship. Among the 480 women who completed the fertility survey, 392 (82%) indicated they had a pre-treatment fertility discussion initiated by a health care provider (HCP) - in 232 cases (48%) the surgeon/nurse and in 130 cases (27%) the medical oncologist/ nurse. Only 14 (16%) of the 88 women not approached by a HCP initiated such a discussion. Rates of FP discussion, referral and uptake are shown below. Among the 38 women who definitely wanted (more) children prior to dx and were offered FP but declined the consult or procedure, the commonest reasons were cost (n = 9) and fear that treatment delay (n = 8) or FP (n = 4) could cause recurrence. Conclusions: Post-intervention FP discussion rates were higher than previously reported. Yet 26% of patients who had definitely/probably not completed their family were not referred for a FP consult. Cost remains a significant FP barrier. Studies are needed to confirm the long-term safety of FP for ER+ patients. [Table: see text]

Recommendations to improve patient-centred care for ductal carcinoma in situ: Qualitative focus groups with women

Background

Patient‐centred care (PCC) improves health‐care experiences and outcomes. Women with ductal carcinoma in situ (DCIS) and clinicians have reported communication difficulties. Little prior research has studied how to improve communication and PCC for DCIS.

Objective

This study explored how to achieve PCC for DCIS.

Design

Canadian women treated for DCIS from five provinces participated in semi‐structured focus groups based on a 6‐domain cancer‐specific PCC framework to discuss communication about DCIS. Data were analysed using constant comparative technique.

Setting and Participants

Thirty‐five women aged 30 to 86 participated in five focus groups at five hospitals.

Results

Women said their clinicians used multiple approaches for fostering a healing relationship; however, most described an absence of desired information or behaviour to exchange information, respond to emotions, manage uncertainty, make decisions and enable self‐management. Most women were confused by terminology, offered little information about the risks of progression/recurrence, uninformed about treatment benefits and risks, frustrated with lack of engagement in decision making, given little information about follow‐up plans or self‐care advice, and received no acknowledgement or offer of emotional support.

Discussion and Conclusions

By comparing the accounts of women with DCIS to a PCC framework, we identified limitations and inconsistencies in women's lived experience of communication about DCIS, and approaches by which clinicians can more consistently achieve PCC for DCIS. Future research should develop and evaluate informational tools to support PCC for DCIS.

Squamous Cell Carcinoma with Regional Metastasis to Axilla or Groin Lymph Nodes: a Multicenter Outcome Analysis

BACKGROUND

Cutaneous squamous cell carcinoma (cSCC) of the trunk/extremities with nodal metastasis represents a rare but significant clinical challenge. Treatment patterns and outcomes are poorly described.

PATIENTS AND METHODS

Patients with cSCC who developed axilla/groin lymph node metastasis and underwent curative-intent surgery between 2005 and 2015 were identified at four Canadian academic centers. Demographics, tumor characteristics, treatment patterns, recurrence rates, and mortality were described. Overall survival (OS) and disease-free survival (DFS) were calculated using Kaplan-Meier analysis. Predictors of survival and any recurrence were explored using Cox regression and logistic regression models, respectively.

RESULTS

Of 43 patients, 70% were male (median age 74 years). Median follow-up was 38 months. Median time to nodal metastasis was 11.3 months. Thirty-one and 12 patients had nodal metastasis to the axilla and groin, respectively. A total of 72% and 7% received adjuvant and neoadjuvant radiation, respectively, while 5% received adjuvant chemotherapy. Following surgery, 26% patients developed nodal and/or distant disease recurrence. Crude mortality rate was 39.5%. Mean OS was 5.3 years [95% confidence interval (CI) 3.9-6.8 years], and 5-year OS was 55.1%. Mean DFS was 4.8 years (95% CI 3.3-6.2 years), and five-year DFS was 49.3%. Any recurrence was the only independent predictor of death [p = 0.036, odds ratio (OR) = 29.5], and extracapsular extension (p = 0.028, OR = 189) and age (p = 0.017, OR = 0.823) were independent predictors of recurrence.

CONCLUSIONS

This represents the largest contemporary series to date of outcomes for patients with axilla/groin nodal metastases from cSCC. Despite aggressive treatment, outcomes remain modest, indicating the need for a continued multidisciplinary approach and integration of new systemic agents.