Interaction between Radiation Therapy and Targeted Therapies in HER2-Positive Breast Cancer: Literature Review, Levels of Evidence for Safety and Recommendations for Optimal Treatment Sequence

Purpose: Over the past twenty years, anti-HER2 targeted therapies have proven to be a revolution in the management of human epidermal growth receptor 2 (HER2)-positive breast cancers. Anti-HER2 therapies administered alone or in combination with chemotherapy have been specifically studied. Unfortunately, the safety of anti-HER2 therapies in combination with radiation remains largely unknown. Thus, we propose a literature review of the risks and safety of combining radiotherapy with anti-HER2 therapies. We will focus on the benefit/risk rationale and try to understand the risk of toxicity in early-stage and advanced breast cancer. Methods: Research was carried out on the following databases: PubMed, EMBASE, ClinicalTrial.gov, Medline, and Web of Science for the terms “radiotherapy”, “radiation therapy”, “radiosurgery”, “local ablative therapy”, and “stereotactic”, combined with “trastuzumab”, “pertuzumab”, “trastuzumab emtansine”, “TDM-1”, “T-Dxd”, “trastuzumab deruxtecan”, “tucatinib”, “lapatinib”, “immune checkpoint inhibitors”, “atezolizumab”, “pembrolizumab”, “nivolumab”, “E75 vaccine”, “interferon”, “anti-IL-2”, “anti-IL 12”, and “ADC”. Results: Association of radiation and monoclonal antibodies such as trastuzumab and pertuzumab (with limited data) seems to be safe, with no excess risk of toxicity. Preliminary data with radiation and of antibody–drug conjugate of trastuzumab combined cytotoxic (trastuzumab emtansine, trastuzumab deruxtecan), given the underlying mechanism of action, suggest that one must be particularly cautious with the association. The safety of the combination of a tyrosine kinase inhibitor (lapatinib, tucatinib) and radiation remains under-studied. The available evidence suggests that checkpoint inhibitors can be safely administrated with radiation. Conclusions: HER2-targeting monoclonal antibodies and checkpoint inhibitors can be combined with radiation, apparently with no excess toxicities. Caution is required when associating radiation with TKI and antibody drugs, considering the limited evidence

Pathologic Response to Neoadjuvant Sequential Chemoradiation Therapy in Locally Advanced Breast Cancer: Preliminary, Translational Results from the French Neo-APBI-01 Trial

Background: Radiation therapy (RT), a novel approach to boost the anticancer immune response, has been progressively evaluated in the neoadjuvant setting in breast cancer (BC). Purpose: We aimed to evaluate immunity-related indicators of response to neoadjuvant chemoradiation therapy (NACRT) in BC for better treatment personalization. Patients and Methods: We analyzed data of the first 42 patients included in the randomized phase 2 Neo-APBI-01 trial comparing standard neoadjuvant chemotherapy (NACT) and NACRT regimen in locally advanced triple-negative (TN) and luminal B (LB) subtype BC. Clinicopathological parameters, blood counts and the derived parameters, total tumor-infiltrating lymphocytes (TILs) and their subpopulation, as well as TP53 mutation status, were assessed as predictors of response. Results: Twenty-one patients were equally assigned to each group. The pathologic complete response (pCR) was 33% and 38% in the NACT and NACRT groups, respectively, with a dose-response effect. Only one LB tumor reached pCR after NACRT. Numerous parameters associated with response were identified, which differed according to the assigned treatment. In the NACRT group, baseline hemoglobin of ≥13 g/dL and body mass index of <26 were strongly associated with pCR. Higher baseline neutrophils-to-lymphocytes ratio, total TILs, and T-effector cell counts were favorable for pCR. Conclusion: This preliminary analysis identified LB and low-TIL tumors as poor responders to the NACRT protocol, which delivered RT after several cycles of chemotherapy. These findings will allow for amending the selection of patients for the trial and help better design future trials of NACRT in BC

Radiation Therapy Delivery Challenges in Older Patients During Coronavirus Disease 2019 Pandemic

Purpose: The management of older patients in radiation therapy (RT) departments has been challenging in the context of the Coronavirus Disease 2019 (COVID-19) outbreak. We report our experience of RT adapted schedules or strategy changes in older patients during the COVID-19 pandemic. Methods and Materials: Patients aged ≥75 years were recruited during weekly chart rounds. All were potentially eligible for a specific intervention to reduce the frequency of patients’ visits to the hospital. The effect of deferring radiation and hypofractionation of RT schedules was assessed in terms of the number of courses initially planned and replanned during the lockdown. Results: Twenty patients were identified during the official lockdown in France (March 17 to May 11). Median age was 78 years (75-95 years). Most patients were male (n = 12, 60%) being treated in the postoperative setting (n = 17, 85%). RT was delayed in 11 cases (55%) with hormonal therapy prescribed in 10 cases (50%). Altered RT fractionation was proposed for 5 cases (25%); combinations of altered fractionation and deferral of radiation were applied in 3 cases (15%). The number of radiation courses initially planned and replanned according to the pandemic context: 563 and 197, respectively (−62%; P < .001). None presented recurrence when RT was initiated, and no patient developed symptomatic COVID-19 infection. Conclusions: In the context of the COVID-19 outbreak, individual risk-based radiation therapy seems to be safe. Systematic screening of patients for COVID-19 before starting radiation therapy is mandatory. In our department the oncogeriatrics expertise availability for daily practice was of great use during the pandemic. Other prospective studies are needed to validate such strategies in case of resurgence of similar outbreaks

How did we take care of our older cancer patients during the first COVID-19 wave? The French experience

International audienceBACKGROUND: The management of older cancer patients has been highly challenging for clinicians in a health-care system operating at maximum capacity during the COVID-19 pandemic. PATIENTS AND METHODS: We analyzed data from 9 different institutions. The primary endpoint was to assess the prevalence of adapted patient care during the pandemic for elderly cancer patients. The secondary endpoint was to assess the incidence of hospitalization and mortality due to COVID-19. All patients were older than 65years of age. RESULTS: We analyzed data from 332 outpatients’ case files between 9th of March and 30th of April 2020. The median age was 75years (range: 65-101) and 53% were male. Because of the COVID-19 pandemic, more than half of the outpatients received modified patient care, defined as postponement or cancellation of surgery, irradiation scheme adapted, systemic treatment or the use of telemedicine. Among patients with localized cancer, 60% had a change in management strategy due to the pandemic. Changes in management strategy were made for 53% of patients at the metastatic stage. GCSF was used , in 83% of patients, increasing considerably in the context of the pandemic. Sixty-nine percent of physicians used telemedicine. In the final analysis, only one patient was hospitalized for COVID-19 infection. No deaths due to COVID-19 were reported in elderly cancer patients during this time period. CONCLUSION: Our study is the first to assess modification of patient care in elderly cancer outpatients during an epidemic. With this unprecedented crisis, our objective is to protect our patients from infection via protective barrier measures and social distancing, but also to guarantee the continuity of cancer care without overexposing this fragile population. Physicians were able to adapt their practice and used new forms of management, like telemedicine