Background: Comparative real-world outcomes for patients with HER2-positive (HER2+) breast cancer receiving adjuvant trastuzumab outside of clinical trials are lacking. This study sought to retrospectively characterize outcomes for patients with node-negative and node-positive breast cancer receiving adjuvant trastuzumab in combination with docetaxel/cyclophosphamide (DCH), docetaxel/carboplatin/trastuzumab (TCH), or fluorouracil/epirubicin/cyclophosphamide followed by docetaxel/trastuzumab (FEC-DH) chemotherapy in Alberta, Canada, from 2007 through 2014. Methods: Disease-free survival and overall survival (OS) analyses for node-negative cohorts receiving DCH (n=111) or TCH (n=371) and node-positive cohorts receiving FEC-DH (n=146) or TCH (n=315) were compared using chi-square, Kaplan-Meier, or Cox multivariable analysis where appropriate. Results: Median follow-up was similar in node-negative (63.9 months) and node-positive (69.0 months) cohorts. The 5-year OS rates in patients with node-negative disease receiving DCH or TCH were similar (95.2% vs 96.9%; P=.268), whereas 5-year OS rates were higher but nonsignificant for patients with node-positive disease treated with FEC-DH compared with TCH (95.2% vs 91.4%; P=.160). Subgroup analysis of node-positive cohorts showed significantly improved OS with FEC-DH versus TCH in patients with estrogen receptor (ER)/progesterone receptor (PR)–positive breast cancer (98.3% vs 91.6%, respectively; P=.014). Conversely, patients with ER/PR-negative disease showed a nonsignificant trend toward higher OS rates with TCH versus FEC-DH (91.6% vs 83.3%, respectively; P=.298). Given the retrospective design, we were unable to capture all potential covariates that may have impacted treatment assignment and/or outcomes. Furthermore, cardiac toxicity data were unavailable. Conclusions: Survival rates of patients with HER2+ breast cancer in our study are comparable to those seen in clinical trials. Our findings support chemotherapy de-escalation in patients with node-negative disease and validate the efficacy of FEC-DH in those with node-positive disease.
Zachary Veitch, Omar F. Khan, Derek Tilley, Domen Ribnikar, Xanthoula Kostaras, Karen King, Patricia Tang and Sasha Lupichuk
Cindy Railton, Sasha Lupichuk, Jennifer McCormick, Lihong Zhong, Jenny Jaeeun Ko, Barbara Walley, Anil A. Joy and Janine Giese-Davis
Purpose: Oncology centers in public health systems often transfer routine follow-up of patients with early-stage breast cancer (BC) to primary care physicians because of the increasing numbers of survivors and evidence supporting the safety of this practice. After transfer of care, it is unknown how BC survivors fare with treatment and surveillance goals, and whether they have unmet needs for access to specialist care. This study conducted in a sample of women in Alberta, Canada, examined adherence with follow-up guidelines, symptoms, and need for a telephone-based survivorship clinic. Methods: Through the Alberta Cancer Registry, we randomly invited women with stage I–III invasive BC (N=960) to participate. Of those, 272 responded, and 240 consented to a structured telephone interview and chart review. Results: Women adhered well to follow-up guidelines for mammogram, but less so for clinical examination and endocrine therapy (ET). However, most patients reported ongoing bothersome symptoms, which tended to be higher in those not on ET. More than one-third of patients reported ongoing needs (managing weight, side effects, exercise adherence, and psychosocial health). Younger, fatigued or depressed, nonurban women not on ET reported the most need for a telephone clinic. Conclusions: Adherence with follow-up goals (examination, mammography, ET) was better than expected. Despite this, interest in a telephone survivorship clinic was high. Perceived needs included symptom management plus support for lifestyle behavior change. Medical follow-up needs might be well-met by discharge to primary care. However, high levels of ongoing symptoms and psychosocial needs would suggest that telephone-based survivorship clinics, psychosocial and exercise interventions, or transition programs might benefit the survivorship experience of patients with BC.
Zachary Veitch, Omar F. Khan, Derek Tilley, Patricia A. Tang, Domen Ribnikar, Douglas A. Stewart, Xanthoula Kostaras, Karen King and Sasha Lupichuk
Background: Reductions in adjuvant chemotherapy dose <85% for historical regimens (ie, cyclophosphamide/methotrexate/fluorouracil) are known to affect breast cancer survival. This threshold, in addition to early versus late dose reductions, are poorly defined for third-generation anthracycline/taxane-based chemotherapy. In patients with breast cancer receiving adjuvant 5-fluorouracil/epirubicin/cyclophosphamide followed by docetaxel (FEC-D), we evaluated the impact of chemotherapy total cumulative dose (TCD), and early (FEC) versus late (D only) dose reductions, on survival outcomes. Patients and Methods: Women with stage I–III, hormone receptor–positive/negative, HER2-negative breast cancer treated with adjuvant FEC-D chemotherapy from 2007 through 2014 in Alberta, Canada, were included. TCD for cycles 1 to 6 of <85% or ≥85% was calculated. Average cumulative dose was also calculated for early (cycles 1–3) and late (cycles 4–6) chemotherapy. Survival outcomes (disease-free survival [DFS] and overall survival [OS]) were estimated using Kaplan-Meier and multivariate analysis. Cohorts were evaluated for uniformity. Results: Characteristics were reasonably balanced for all cohorts. Overall, 1,302 patients were evaluated for dose reductions, with 16% being reduced <85% (n=202) relative to ≥85% (n=1,100; 84%). Patients who received TCD ≥85% relative to <85% had superior 5-year DFS (P=.025) and OS (P<.001) according to Kaplan-Meier analysis, which remained significant on univariate and multivariate analyses. In stratified late and early dose reduction cohorts, DFS and OS showed a significant inferior survival trend for dose reduction early in treatment administration in 5-year Kaplan-Meier (P=.002 and P<.001, respectively) and multivariate analyses (hazard ratio [HR], 1.46; P=.073, and HR, 1.77; P=.011, respectively). Dose delays of <14 or ≥14 days and granulocyte colony-stimulating factor use did not affect outcomes. Conclusions: Chemotherapy TCD <85% for adjuvant FEC-D affects breast cancer survival. Late reductions (D only) were not shown to adversely affect DFS or OS. Conversely, early reductions (FEC±D) negatively affected patient outcomes.