[Prognostic factors for head and neck cancer reirradiation: A systematic review]

To specify the effectiveness of head and neck cancer reirradiation and make a synthesis of prognostic factors established by published series of patients.

Original series of external reirradiation of head and neck cancer with at least ten patients were sought in Medline database.

Exclusive reirradiation with or without concurrent chemotherapy offers 11 months of median overall survival, versus 6 months for chemotherapy alone, and 20 to 40% of the patients are still alive two years after treatment. Postoperative reirradiation allows 3 years overall survival from 40 to 60%. However, side effects of grade 3 or more arise in more than half of patients. Patient-related good prognostic factors are male, young age, good performance status without comorbidities. Those related to the disease are low rT and rN stage, poor differentiation, other than squamous cell carcinomas and a nasopharyngeal, oropharyngeal or laryngeal location. Concerning the treatment, surgical resection, a dose higher than 50 to 60Gy in a smaller-irradiated volume, an interval between the two treatments of more than 2 years and the use of an innovating technology are the most commonly highlighted prognostic factors. Concurrent chemotherapy is often associated with higher toxicity rates, without improving overall survival, unless using cisplatin for selected patients.

Head and neck cancer reirradiation achieves long-term survival outcomes. However, regarding to its associated side effects, patients need to be carefully selected based on prognostic factors.