Support for patients with head-and-neck cancer was analyzed qualitatively through a semi-structured interview. The subjects were four patients with head-and-neck cancer who had completed radiotherapy after temporary discontinuation. The results were classified based on the categories by the analysis into ‘radiotherapy’, ‘adverse events’, ‘thoughts during temporary discontinuation of therapy’, ‘support for continuation of therapy’, and ‘after completion of therapy’. Hope for possible treatment and the will to live were the main factors supporting the patients to complete radiotherapy. For example, one patient had previously thought that it was all over if cancer was found in a lymph node, but was told that treatment was still possible. Nurses should provide support to patients by offering hope, even during temporary discontinuation of therapy due to adverse events, while understanding the underlying thoughts of patients about their therapy and life. A strong will of patients to recover and live, the presence and words of their families and of patients receiving similar therapy, the attitudes of nurses, and the words of physicians were all important in supporting patients to complete radiotherapy.