Abstract 18: Therapeutic potential of cold physical plasma in palliative cancer care: Introduction and perspectives

Abstract

Abstract Background: Patients suffering from advanced head and neck tumors frequently suffer from superinfected chronic wounds caused by necrotic tissue due to progressive tumor growth, weak systemic and local immunologic response and various accompanying illnesses. Because of wound vulnerability, local antiseptic wound care of microbial-contaminated tumor areas is frequently complicated by bleeding, pain and patient dissatisfaction. Plasma medicine in cancer is of palliative benefit in these cases and among the fastest growing of the current applications of cold atmospheric pressure physical plasma (CAP). Since several plasma medical devices have received approval for treatment of infected skin and ulcerations by the relevant agencies, limited clinical tests have begun on humans and palliative treatment of cancer patients with contaminated ulcers. This report as part of a large-scale study program illustrates one recent impressive application of CAP to a patient suffering from advanced head and neck cancer. Materials and Methods: After curably intended surgical cancer treatment of a well-differentiated squamous cell carcinoma of the left cheek January 2015, the 51-year-old patient noticed a rapidly progressive swelling on the left neck in June. CT scan indicated a large contrast enhancing mass, which was suspected to be tumor recurrence. Operative findings revealed inoperability due to infiltrating the vascular wall of the external carotid. After a palliative intended combined radio-chemotherapy, the tumor was characterized by progressive growth with exulceration. Due to the vulnerability of the extended bacterially contaminated wound and the underlying carotid artery, wound care was difficult. Since October 2015, a supportive palliative cancer treatment using CAP has been started with the patient's written consent. The exulcerative tumor growth region received treatment with the kINPenMED (Neoplas GmbH, Greifswald, Germany) by scanning the surface for 5 minutes in a meandering manner. Plasma treatment continued to be performed every 3 days. Wound care was implemented in conjunction with an antiseptic wound dressing. Results: The superinfected necrotic tumor areas appeared to be clean of cell detritus and bacteria. Microbiological examination revealed a reduction of bacterial colonization which led to decrease of wound odor, too. Due to the decrease of inflammation, vulnerability and pain have been reduced significantly. Upon CAP therapy a partial tumor response with tumor mass reduction was observed. The ulcerated tumor area has been reduced to one-quarter of its original size. The underlying carotid artery is still intact and ultrasound investigation revealed a regular blood flow. Histologic examinations revealed an increased amount of apoptic tumor cells and a local increase of immune defense. Furthermore, a desmoplastic reaction of the conjunctive tissue represented by a higher proliferation rate of fibroblasts could be depicted. No plasma-relevant systemic side effects have occurred. Conclusion: By sufficient reduction of bacterial colonization, decrease of inflammation, wound vulnerability and pain, CAP constitutes an innovative and valuable treatment option in palliative cancer care. Local tumor mass reduction is an unexpected and promising response during CAP treatment and has to be further examined. Plasma-unique synergies between reactive species, charges and electric fields must be more fully explored and understood. The impressive demonstration of medical efficacy of CAP in cancer ulcerations supports optimism for trials of plasma medical devices with the intention of an adaptive cancer treatment protocol. Citation Format: Christian Seebauer, Thomas von Woedtke, Klaus-Dieter Weltmann, Vandana Miller, Masaru Hori, Hans-Robert Metelmann. Therapeutic potential of cold physical plasma in palliative cancer care: Introduction and perspectives [abstract]. In: Proceedings of the AACR-AHNS Head and Neck Cancer Conference: Optimizing Survival and Quality of Life through Basic, Clinical, and Translational Research; April 23-25, 2017; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2017;23(23_Suppl):Abstract nr 18.