Abstract
BACKGROUND: Non-thermal plasma (NTP) refers to an ionized gas composed of ions, electrons and other reactive agents. The anticancer properties of NTP have been proven in vitro and in vivo. The 10-year local recurrence risk (LRR) in breast cancer patients after breast conservation therapy (i.e., lumpectomy, typically followed by radiation therapy) is still as high as 15-20%. NTP could be used to further treat the tumor bed to reduce the LRR. METHODS: Our primary objective is to determine the safe and tolerable dose of NTP treatment following breast cancer lumpectomy. Our secondary objectives are to assess the safety and tolerability of NTP and to assess the cosmetic effects of NTP treatment in patients with breast cancer. Our exploratory objective is to assess the impact of NTP treatment on cancerous and normal tissues. Patients are followed for up to 3 months after NTP treatment. The patients are divided into 3 groups: group A (n = 3): NTP treatment of part of the tumor bed ex vivo. Group B (n = 3): NTP treatment of part of the tumor bed in situ (all treated tissues are removed for analysis). Group C (n = 6-24): dose escalation per "3 + 3 Design" up to a maximum dose level of 3. NTP treatment of part of the tumor bed in situ (the treated parts of the tumor bed will not be excised, except for a small portion for analysis). DISCUSSION: The safety and tolerability of treatment will be evaluated by means of dose-limiting toxicity, adverse event (AE) and serious adverse event reports; physical examinations; and laboratory safety evaluations. AEs will be coded according to CTCAE v5.0. The results will be tabulated to examine their frequency, grade, and relationship to the study treatment. The results of laboratory assessments will be evaluated similarly. The number of patients with cosmetic alterations linked to NTP treatment and the type of alteration will be assessed through quality of life questionnaires (questions about breast appearance and texture) and through photo collection. This is the first clinical trial to study the safety and tolerability of NTP in an all-breast cancer patient cohort. TRIAL REGISTRATION: Name of the registry: ClinicalTrials.gov. TRIAL REGISTRATION NUMBER: NCT06222788. Date of registration: 01/15/2024. URL of trial registry record: https://clinicaltrials.gov/study/NCT06222788 .