Intensive ongoing research in the field of anticancer treatment points the atmospheric non-thermal plasma (NTP) as a new potential mean to attack tumors from a distinct innovative approach. The antitumor effect of NTP has been now clearly shown in vivo on murine models with various cancer types (glioblastoma, melanoma, colon, pancreas, blader, ovary) [1]. Although the mechanism is far from being fully understood, the therapeutic effect is admitted. To date, the literature reports mainly induction of apoptosis, effect which is not restricted to cancer cells and probably mask other aspects of the NTP for cancer therapy. Our work focuses on “soft” application allowing highlighting interesting effects as recently shown [2] on blood vessel parameters: blood flow and tissue oxygenation. With this aim to avoid the deleterious impact of plasma on cells and tissues, various plasma conditions were established to allow a daily treatment without damage. Plasma Gun helium NTP used in our work not only leads to the production of reactive species, but also generates transient electric fields. In addition to previous results obtained on colon and pancreas carcinoma, recent results we obtained in the treatment of 4T1 breast carcinoma are in favor of a triggering effect, evidenced for the first time, and clearly indicate a tumor growth regulation. Taking into consideration the recent vessel normalization based-cancer treatment, the NTP effect should be further investigated in view of blood vessels structure and function (blood flow) as well as tumor hypoxia compensation to confirm a possible NTP-based adjuvant approach for cancer treatments. These results suggest a new way to consider the plasma and its therapeutic delivery in NTP-based tumor therapy in combination or not with chemotherapy and radiotherapy. In the presentation, after a short introduction on the biomedical applications of plasmas, we will first make a rapid survey of the developments in the field of plasma antitumor effect around the world and then concentrate on the different results obtained in the context the PLASMED/PLASMEDNORM projects in Orleans. Acknowledgements This work is supported by the APR Region Centre PLASMED and PLASMEDNORM and by ANR2010BLAN093001 PAMPA. TD is supported by the French Ministry of Research, DR by Région Centre and CNRS, and VS by Conseil Général du Loiret. References [1] Brulle L et al, 2012 PloSOne 7 e52653 [2] G. Collet et al, 2014 Plasma Sources Sci. Technol. 23 012005