Long-term follow-up in patients treated with curative electrochemotherapy for cancer in the oral cavity and oropharynx

Abstract

Conclusion: ECT can be a safe curative mono modality treatment, especially in tongue cancer. The future role for ECT in head and neck cancer needs to be further investigated. Introduction: Electrochemotherapy (ECT) is a cancer treatment modality that uses electroporation to increase the intracellular accumulation of hydrophilic chemotherapeutic drugs, especially bleomycin. Objectives: To report the 5-year local tumor control, safety of treatment and survival after ECT, and the 1-year quality-of-life (QoL) data. Materials and methods: Nineteen patients with primary head and neck cancer were included and treated with ECT with curative intent. All except one patient had squamous cell carcinoma (SCC). Radiotherapy (RT) was performed in all patients with SCC and tumor infiltration ≥5 mm. The EORTC H&N 35 questionnaire was used at baseline and 12 months after treatment. The Wilcoxon signed rank test and McNemar’s test were used for paired data and Mann Whitney U-test and Fishers exact test were used for independent data (sub-group comparison). Results: There were no local recurrences in the follow-up period. Thirteen patients were treated with adjuvant RT. The six patients that were treated with ECT alone were tumor-free and alive 5 years after treatment. There was one serious adverse event reported; aspiration after treatment of a tongue base tumor. The tumor-specific 5-year survival was 75%. The QoL outcome 1 year after ECT showed a significant increase in problems with senses (taste, smell), speech, mouth opening and xerostomia. The QoL outcome also showed worse outcome in the smoking patients regarding speech, in the patients receiving adjuvant RT regarding mouth dryness and swallowing and in the patients with non-tongue oral cavity cancer regarding need for painkillers.

Keywords:

• Electrochemotherapy
• bleomycin
• head and neck cancer
• squamous cell carcinoma
• quality-of-life
• local control
• survival

Acknowledgments

This study, supported by the Örebro County Council, was approved by the Medical Products Agency (10) in Sweden and by the Regional Board for Ethical Evaluation in Uppsala.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.