Second Re-irradiation: Clinical Examples of Worthwhile Treatment

Introduction: Improved treatment approaches have resulted in longer survival of patients with certain types of incurable cancer, without eliminating the need for symptom palliation and supportive measures. In this context, re-irradiation is an increasingly important option. Little data exists about a second or repeat re-irradiation. Methods: From a single institution database, patients who received a second re-irradiation with cumulative equivalent doses (equivalent dose in 2-Gy fractions (EQD2) for late effects, alpha/beta-value 3 Gy) of more than 90 Gy and survived for more than six months were identified. Illustrative clinical examples were provided. Results: The examples describe the treatment of sacral bone metastases, recurrent rectal cancer, and pelvic lymph node metastases. The maximum cumulative EQD2 was 142 Gy. Symptomatic responses were obtained without clinically relevant side effects. Conclusion: These three cases illustrate that a second re-irradiation has the potential to provide worthwhile palliative effects without causing overt late toxicity during the remaining life time. In patients who tolerated previous radiotherapy well, further re-irradiation may contribute to the ever-increasing armamentarium of options that increase the survival of patients with incurable cancer and try to prolong the time period where independent living is possible.