Until now, no long-term results of any study support this suggestion. We believe that only the complete 24-h treatment schedule guarantees that PDR brachytherapy will preserve all the radiobiologic advantages of LDR brachytherapy. In our experience, there exist no logistical or practical problems with the 24-h treatment schedule of PDR brachytherapy administered for 3–6 days. If we compare our results from PDR-iBT in head and neck AZD2281 cancer, mostly administered as postoperative brachytherapy, with the results from LDR brachytherapy , , , ,  and ,
we see prevailing similarities in the results. The reported local control rates depend on the tumor size have values between 78% and 93% for T1/T2 tumors and 57% for T3/T4 tumors , , , , , , ,  and . Local control rates in our study also correlate with tumor size and reach 86% after 5 years and 83% after 10 years for all patients. In this context, it is necessary to mention the limitations of the Kaplan–Meier method for local control estimates because competing events such as deaths from other causes can modify
the results. Nonetheless, it is obvious that BYL719 mw such excellent local control rates have been achievable only in the era of modern image-guided brachytherapy, with optimal interleaving of brachytherapy and nonmutilating surgery. In this context, our results are also congruent with excellent results of Al-Mamgani et al. (32). Recently, there has also been a sharp increase in the use of HDR brachytherapy for the treatment of head and neck tumors. Data relating to HDR brachytherapy in the treatment of head and neck cancer have been largely retrospective , , , , , , , , , ,  and , but there exists one randomized
study (65) with a relatively small number of patients. Unfortunately, in the randomized study, only 59 patients were analyzed and therefore no valid conclusions can be drawn. The retrospective results Benzatropine seem to indicate that the results of HDR brachytherapy may be similar to the results of LDR and PDR brachytherapy. The most feared serious side effects are soft tissue and bone necrosis. The probability for this complication depends in particular on the total dose, dose rate, intersource spacing, implant volume, quality index, and volume gradient ratio , , ,  and . Osteoradionecrosis also correlate with the distance between the sources and the bone. The risk of soft tissue necrosis in LDR brachytherapy varies between 20% and 30%—most of these lesions heal spontaneously and necrosis of bone may occur in about 10–20% of the patients. For example, Lapeyre et al. (35) reported late complications in 34 of 82 patients (43%), 8 of them (9.8%) were in Grade 3. Beitler et al. (33) reported a high rate of late side effects—with severe or moderate late sequelae being seen in 12 of 23 patients (52.2%). Similarly, in a series reported by Mendenhall et al. (36), 7 of 15 patients (46.