Adjuvant Trastuzumab Without Chemotherapy For Treating Early HER2-Positive Breast Cancer In Older Patients: A Cohort Study Accompanying With The RESPECT Trial

Purpose To gauge the effects of treatment practices on prognosis for all older patients with HER2-positive breast cancer, particularly to determine whether adjuvant trastuzumab alone can offer benefit over no adjuvant therapy. This report accompanies the RESPECT study, a randomized-controlled trial (RCT) comparing trastuzumab monotherapy with trastuzumab-plus-chemotherapy for early HER2-positive breast cancer.Patients and methods Patients who declined the RCT were treated based on the physician’s discretion. We studied the (1) trastuzumab-plus-chemotherapy group, (2) trastuzumab-monotherapy group, and (3) non-trastuzumab group (no therapy or anticancer therapy without trastuzumab). The primary endpoint was disease-free survival (DFS), which was compared using the propensity-score method.Results We enrolled 398 eligible patients, aged over 70 years, with HER2-positive invasive breast cancer, of whom 275 (69%) were in the RCT, and 123 (31%) were in this cohort group. The median age was 74.5 years. Among cohort group treatment categories were as follows: (1) trastuzumab-plus-chemotherapy group (n = 36, 30%), (2) trastuzumab-monotherapy group (n = 52, 43%), and (3) non-trastuzumab group (n = 32, 27%). A total of 73% of patients received trastuzumab-containing regimens, with or without chemotherapy. The 3-year DFS was 92.3% in the trastuzumab-plus-chemotherapy group, 89.2% in the trastuzumab-monotherapy group, and 82.5% in the non-trastuzumab group. DFS in the non-trastuzumab group was lower than in the trastuzumab-plus-chemotherapy and trastuzumab-monotherapy groups (propensity-adjusted HR: 3.29; 95% CI: 1.15–9.39; P = 0.026). The relapse-free survival in the non-trastuzumab group was lower than in the trastuzumab-plus-chemotherapy and trastuzumab monotherapy groups (propensity-adjusted HR = 7.80; 95% CI: 2.32–26.2, P < 0.0001). Chemotherapy with trastuzumab or trastuzumab monotherapy did not affect health-related quality of life (HRQoL) at 36 months.Conclusions Trastuzumab-treated patients had better prognoses than patients not treated with trastuzumab without deterioration of HRQoL. Thus, trastuzumab monotherapy can be considered for patients who reject chemotherapy.Trial registration number The protocol was registered on the website of the University Hospital Medical Information Network (UMIN), Japan (protocol ID: UMIN 000028476).

Health-Related Quality of Life With Trastuzumab Monotherapy Versus Trastuzumab Plus Standard Chemotherapy as Adjuvant Therapy in Older Patients With HER2-Positive Breast Cancer

PURPOSE We report findings on quality of life (QoL) in the RESPECT trial, which compared adjuvant trastuzumab monotherapy with trastuzumab plus chemotherapy in older patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer (BC). PATIENTS AND METHODS Patients age 70-80 years with human epidermal growth factor receptor 2-positive surgically treated breast cancer were randomly assigned to receive trastuzumab (T) or trastuzumab plus chemotherapy (T + C). QoL was assessed using the Functional Assessment of Cancer Therapy-General (FACT-G), Philadelphia Geriatric Center Morale Scale, Hospital Anxiety and Depression Scale, Patient Neurotoxicity Questionnaire, and Tokyo Metropolitan Institute of Gerontology Index of Competence at baseline and after 2, 12, and 36 months. Comparisons were based on individual changes from baseline and were performed by Fisher’s test or mixed-model repeated-measures. RESULTS Among 275 patients in the parent study, 231 (84%) (average age: 74 years) were included in the analysis. At 2, 12, and 36 months, 198, 177, and 178 patients completed surveys, and the mean FACT-G scores at each survey point were 78.9, 80.4, 82.7, and 79.1 in group T and 79.5, 74.5, 78.4, and 78.5 in group T + C. Compared with group T + C, the proportion of patients showing QoL deterioration (≥ 5 points decrease from baseline in FACT-G) was significantly lower at 2 months (31% v 48%; P = .016) and 12 months (19% v 38%; P = .009). In group T, the Hospital Anxiety and Depression Scale score ( P = .003) and the proportion of severe sensory peripheral neuropathy ( P = .001) were significantly lower at 2 months, and Philadelphia Geriatric Center Morale Scale and Tokyo Metropolitan Institute of Gerontology Index of Competence scores were significantly higher ( P = .024, .042) at 12 months. At 36 months, there were no significant differences in any QoL items. CONCLUSION Detrimental effects of adjuvant chemotherapy on global QoL, morale, and activity capacity lasted for at least 12 months but were not observed at 36 months.

Randomized Controlled Trial of Trastuzumab With or Without Chemotherapy for HER2-Positive Early Breast Cancer in Older Patients

PURPOSE Adjuvant trastuzumab monotherapy has not been compared with trastuzumab + chemotherapy. We investigated the relative value of trastuzumab monotherapy for older patients with breast cancer. METHODS This study was an open-label, randomized controlled study with a treatment selection design in which a noninferiority criterion was predefined. Patients aged 70-80 years with surgically treated human epidermal growth factor receptor 2–positive invasive breast cancer received trastuzumab monotherapy or trastuzumab + chemotherapy. The primary end point was disease-free survival (DFS) with assessment of prespecified hazard ratio (HR), relapse-free survival (RFS), adverse events (AEs), health-related quality of life (HRQoL), and restricted mean survival time (RMST). RESULTS The study involved 275 patients (mean age, 73.5 years) who were followed up for a mean of 4.1 years (range, 0.3-8.0 years). The percentages of patients by cancer stage were as follows: I (pT > 0.5 cm), 43.6%; IIA, 41.7%; IIB, 13.5%; and IIIA, 1.1%. Three-year DFS was 89.5% with trastuzumab monotherapy versus 93.8% with trastuzumab + chemotherapy (HR, 1.36; 95% CI, 0.72 to 2.58; P = .51). At 3 years, RMST differed by −0.39 months between arms (95% CI, −1.71 to 0.93; P = .56). Three-year RFS was 92.4% with trastuzumab monotherapy versus 95.3% with trastuzumab + chemotherapy (HR, 1.33; 95% CI, 0.63 to 2.79; P = .53). Common AEs were anorexia (7.4% v 44.3%; P < .0001) and alopecia (2.2% v 71.7%; P < .0001), and grade 3/4 nonhematologic AEs occurred in 11.9% versus 29.8% ( P = .0003) for trastuzumab monotherapy versus trastuzumab + chemotherapy, respectively. Clinically meaningful HRQoL deterioration rate showed significant differences at 2 months (31% for trastuzumab monotherapy v 48% for trastuzumab + chemotherapy; P = .016) and at 1 year (19% v 38%; P = .009). CONCLUSION The primary objective of noninferiority for trastuzumab monotherapy was not met. However, the observed loss of survival without chemotherapy was < 1 month at 3 years. Therefore, and in light of the lower toxicity and more favorable HRQoL profile, trastuzumab monotherapy can be considered an adjuvant therapy option for selected older patients.

Plasma HER2ECD a promising test for patient prognosis and prediction of response in HER2 positive breast cancer: Results of a randomized study - SAKK 22/99

Background The HER2 extracellular domain shed in blood (HER2 ECD ) is reported to rise and fall in parallel with HER2+ breast cancer behavior. In this study, we evaluated the clinical relevance of plasma HER2 ECD values in patients with metastatic breast cancer treated in the SAKK22/99 trial comparing trastuzumab monotherapy followed by trastuzumab-chemotherapy combination at progression versus upfront combination therapy. Methods Quantitative assessment of plasma HER2 ECD was performed in 133 patients at baseline; after 2-24 hours; at 3 weeks; at first response evaluation (8-9 weeks); and at tumor progression. Associations with tumor characteristics, disease course and trial treatment were evaluated. Results Baseline HER2 ECD levels were stable within 24 hours after the first trastuzumab injection. These plasma values correlated positively with the HER2 gene ratio (r s =0.39, P <0.001) and HER2 protein expression levels (r s =0.36, P <0.001) but not with ER/PR status of the primary tumor. HER2 ECD baseline levels were positively associated with the presence of visceral disease ( P =0.05) and poor patients’ outcome (Cox-regression: P =0.009). Patients with high baseline levels ( > 35ng/ml) had the worst overall survival ( P =0.03) if treated with upfront combination therapy. Conversely, patients with low HER2 ECD baseline values (<15ng/ml) had longer time to progression on combined trastuzumab-chemotherapy when first treated with trastuzumab monotherapy ( P =0.02). Monitoring HER2 ECD levels during the course of the trial revealed significant time ( P =0.001) and time-treatment arm interactions ( P =0.0007). Under upfront trastuzumab alone, the HER2 ECD levels remained stable until just before disease progression. In patients responding to combination treatment HER2 ECD levels decreased to > 20%. Conclusions Plasma HER2 ECD levels in patients with metastatic breast cancer reflect HER2 disease status. This robust biomarker might help identifying patients without visceral disease profiting from a sequential treatment’s modality. Monitoring HER2 ECD levels during trastuzumab monotherapy could help defining the optimal time to introduce chemotherapy.

Plasma HER2ECD a promising test for patient prognosis and prediction of response in HER2 positive breast cancer: Results of a randomized study - SAKK 22/99

Background The HER2 extracellular domain shed in blood (HER2 ECD ) is reported to rise and fall in parallel with HER2+ breast cancer behavior. In this study, we evaluated the clinical relevance of plasma HER2 ECD values in patients with metastatic breast cancer treated in the SAKK22/99 trial comparing trastuzumab monotherapy followed by trastuzumab-chemotherapy combination at progression versus upfront combination therapy. Methods Quantitative assessment of plasma HER2 ECD was performed in 133 patients at baseline; after 2-24 hours; at 3 weeks; at first response evaluation (8-9 weeks); and at tumor progression. Associations with tumor characteristics, disease course and trial treatment were evaluated. Results Baseline HER2 ECD levels were stable within 24 hours after the first trastuzumab injection. These plasma values correlated positively with the HER2 gene ratio (r s =0.39, P <0.001) and HER2 protein expression levels (r s =0.36, P <0.001) but not with ER/PR status of the primary tumor. HER2 ECD baseline levels were positively associated with the presence of visceral disease ( P =0.05) and poor patients’ outcome (Cox-regression: P =0.009). Patients with high baseline levels ( > 35ng/ml) had the worst overall survival ( P =0.03) if treated with upfront combination therapy. Conversely, patients with low HER2 ECD baseline values (<15ng/ml) had longer time to progression on combined trastuzumab-chemotherapy when first treated with trastuzumab monotherapy ( P =0.02). Monitoring HER2 ECD levels during the course of the trial revealed significant time ( P =0.001) and time-treatment arm interactions ( P =0.0007). Under upfront trastuzumab alone, the HER2 ECD levels remained stable until just before disease progression. In patients responding to combination treatment HER2 ECD levels decreased to > 20%. Conclusions Plasma HER2 ECD levels in patients with metastatic breast cancer reflect HER2 disease status. This robust biomarker might help identifying patients without visceral disease profiting from a sequential treatment’s modality. Monitoring HER2 ECD levels during trastuzumab monotherapy could help defining the optimal time to introduce chemotherapy.

Plasma HER2ECD a promising test for patient prognosis and prediction of response in HER2 positive breast cancer: Results of a randomized study - SAKK 22/99.

Background: The HER2 extracellular domain shed in blood (HER2ECD) is reported to rise and fall in parallel with HER2+ breast cancer behavior. In this study, we evaluated the clinical relevance of plasma HER2ECD values in patients with metastatic breast cancer treated in the SAKK22/99 trial comparing trastuzumab monotherapy followed by trastuzumab-chemotherapy combination at progression versus upfront combination therapy. Methods : Quantitative assessment of plasma HER2ECD was performed in 133 patients at baseline; after 2-24 hours; at 3 weeks; at first response evaluation (8-9 weeks); and at tumor progression. Associations with tumor characteristics, disease course and trial treatment were evaluated.Results: Baseline HER2ECD levels were stable within 24 hours after the first trastuzumab injection. These plasma values correlated positively with the HER2 gene ratio (rs=0.39, P<0.001) and HER2 protein expression levels (rs=0.36, P<0.001) but not with ER/PR status of the primary tumor. HER2ECD baseline levels were positively associated with the presence of visceral disease (P=0.05) and poor patients’ outcome (Cox-regression: P=0.009). Patients with high baseline levels (>35ng/ml) had the worst overall survival (P=0.03) if treated with upfront combination therapy. Conversely, patients with low HER2ECD baseline values (<15ng/ml) had longer time to progression on combined trastuzumab-chemotherapy when first treated with trastuzumab monotherapy (P=0.02). Monitoring HER2ECD levels during the course of the trial revealed significant time (P=0.001) and time-treatment arm interactions (P=0.0007). Under upfront trastuzumab alone, the HER2ECD levels remained stable until just before disease progression. In patients responding to combination treatment HER2ECD levels decreased to >20%. Conclusions: Plasma HER2ECD levels in patients with metastatic breast cancer reflect HER2 disease status. This robust biomarker might help identifying patients without visceral disease profiting from a sequential treatment’s modality. Monitoring HER2ECD levels during trastuzumab monotherapy could help defining the optimal time to introduce chemotherapy.

Plasma HER2ECD a promising test for patient prognosis and prediction of response in HER2 positive breast cancer: Results of a randomized study - SAKK 22/99

Background The HER2 extracellular domain shed in blood (HER2 ECD ) is reported to rise and fall in parallel with HER2+ breast cancer behavior. In this study, we evaluated the clinical relevance of plasma HER2 ECD values in patients with metastatic breast cancer treated in the SAKK22/99 trial comparing trastuzumab monotherapy followed by trastuzumab-chemotherapy combination at progression versus upfront combination therapy. Methods Quantitative assessment of plasma HER2 ECD was performed in 133 patients at baseline; after 2-24 hours; at 3 weeks; at first response evaluation (8-9 weeks); and at tumor progression. Associations with tumor characteristics, disease course and trial treatment were evaluated. Results Baseline HER2 ECD levels were stable within 24 hours after the first trastuzumab injection. These plasma values correlated positively with the HER2 gene ratio (r s =0.39, P <0.001) and HER2 protein expression levels (r s =0.36, P <0.001) but not with ER/PR status of the primary tumor. HER2 ECD baseline levels were positively associated with the presence of visceral disease ( P =0.05) and poor patients’ outcome (Cox-regression: P =0.009). Patients with high baseline levels ( > 35ng/ml) had the worst overall survival ( P =0.03) if treated with upfront combination therapy. Conversely, patients with low HER2 ECD baseline values (<15ng/ml) had longer time to progression on combined trastuzumab-chemotherapy when first treated with trastuzumab monotherapy ( P =0.02). Monitoring HER2 ECD levels during the course of the trial revealed significant time ( P =0.001) and time-treatment arm interactions ( P =0.0007). Under upfront trastuzumab alone, the HER2 ECD levels remained stable until just before disease progression. In patients responding to combination treatment HER2 ECD levels decreased to > 20%. Conclusions Plasma HER2 ECD levels in patients with metastatic breast cancer reflect HER2 disease status. This robust biomarker might help identifying patients without visceral disease profiting from a sequential treatment’s modality. Monitoring HER2 ECD levels during trastuzumab monotherapy could help defining the optimal time to introduce chemotherapy.

Complete Remission of Metastatic HER2+ Oesophagogastric Junctional Adenocarcinoma under long-term Trastuzumab Treatment

Metastatic gastric cancer (GC) and oesophagogastric junctional (OGJ) adenocarcinoma have a poor clinical outcome with a high worldwide burden of disease. A 65-year old male patient with microcytic anemia was diagnosed with stage IV OGJ adenocarcinoma with multiple liver metastases. Immunohistochemical analysis revealed a high expression of HER2 (3+). Palliative chemotherapy with FLOT (oxaliplatin, 5-fluorouracil, leucovorin and docetaxel) in combination with trastuzumab was initiated. Due to severe adverse events, the therapy was de-escalated to trastuzumab monotherapy after six months of treatment. Initial restaging revealed partial response after the combination therapy of FLOT with trastuzumab. After reduction to trastuzumab monotherapy, the disease remained stable for two years until radiological complete response was observed. Trastuzumab monotherapy was continued for another two years to maintain complete response. Eleven months after the discontinuation of the therapy, no recurrence of the disease was detected. In conclusion, complete response can be achieved under trastuzumab monotherapy in exceptional responders.

Long-term responders to trastuzumab monotherapy in first-line HER-2+ advanced breast cancer: characteristics and survival data

Background The impact of HER2-targeted therapy alone followed by the addition of chemotherapy at disease progression (PD) versus upfront combination was investigated by the SAKK 22/99 trial. The aim of this exploratory analysis of the SAKK 22/99 trial was to characterize the specific subset of patients deriving long-term benefit from trastuzumab monotherapy alone and to identify potential predictive factors of long-term response. Methods This is an unplanned post-hoc analysis of patients randomized to Arm A (trastuzumab monotherapy). Patients were divided in two groups: patients with durable clinical benefit from trastuzumab monotherapy and short-term responders without durable clinical benefit from trastuzumab monotherapy Univariate and multivariate analyses of clinical characteristics correlating with response duration was performed. Results Eighty six patients were randomized in arm A, 24 patients (28%) were long-term responders and 62 (72%) were short-term responders with a 5y-overall survival (OS) of 54% (95% CI 31–72) and of 18% (95%CI 10–30), respectively. Absence of ER expression, absence of PgR expression and presence of visceral disease emerged as possible negative predictive factors for durable clinical benefit. Conclusion Durable clinical benefit can be achieved with trastuzumab monotherapy in a subgroup of HER2-positive patients with advanced disease and it is predictive for longer OS. Further investigations of predictive biomarkers are necessary to better characterize this subgroup of patients and develop further de-escalating strategies. Trial registration NCT00004935; first posted 27.01.2003, retrospectively registered.