Preliminary report of pulsed dose rate brachytherapy in head-and-neck cancer

To assess the feasibility and acute/delayed toxicity of pulsed-dose-rate brachytherapy (PDR BT) in head-and-neck tumors.

45 head and neck cancer patients underwent interstitial or contact PDR BT at a dose of 10.2-70 Gy (median, 70 Gy) and 0.6 or 1.0 Gy/pulse/h. 42 patients were administered BT as part of their curative treatment; 32 of them had sole BT. Three reirradiated patients with recurrent tumor had palliative BT.

PDR BT was well tolerated. Intense bleeding was the only complication associated with catheter removal from the tongue and bucca. 44 patients who completed BT experienced acute mucositis. Grade 3 toxicity of skin and oral mucosa occurred in three (6.8%) and six patients (13.6%), respectively. At a median follow-up of 22 months (range, 2-67 months), late serious toxicity (grade 4, for soft tissue and bone) was seen in seven patients (15.9%). Among the parameters analyzed, only dental care performed before BT had a significant impact on mucosal side effects. Acute severe mucositis was observed in 23% of patients without dental care compared to 0% of those with dental care (p=0.044). Late severe mucositis occurred in 17.7% and 26.9% of the respective patients (p=0.035), overall in 23%. The larger the volume encompassed by the reference isodose, the more late (p=0.004) mucosal reactions were observed.

PDR BT continued over a few days is a feasible and safe approach in head-and-neck tumors; however, it is accompanied by some toxicity. Dental care should precede isotope application.