RESUMO
OBJECTIVE: To examine the outcome of patients receiving interstitial pulsed-dose-rate brachytherapy (PDR-BT) after pelvic radiation therapy for treatment of an anal squamous cell carcinoma. METHODS AND MATERIALS: Twenty-one patients were identified: 13, six, and two with stages I, II, and III tumors, respectively. After receiving received pelvic irradiation +/- concurrent chemotherapy, patients were delivered a PDR-BT boost to the residual tumor, with intention to deliver a minimal total dose of 60 Gy. The greatest dimension of residual tumor at the time of brachytherapy procedure was 12.5 mm (range: 0-20 mm). Brachytherapy implantation was performed according to the Paris system, only one plane implant being used. RESULTS: Median dose delivered through BT was 20 Gy (range: 10-30 Gy). Median number of pulses was 48 (range: 20-80 pulses). Median treated volume was 9 cm(3) (range: 5-16 cm(3)). Median dose per pulse was 40 cGy (range: 37.5-50 cGy). No Grade 3 or more acute toxicity was reported. No Grade 3 or more delayed toxicity was seen among 18 patients with more than 6 months follow-up. Median followup was 47 months (range: 6-73 months). Twenty patients (95%) were alive at last follow-up. Tumor relapses were experienced in four patients (19%), including local relapse in three patients (14%). CONCLUSION: With almost 4 years median followup, this study confirms previous data suggesting that PDR-BT is effective and safe in this indication. Local control rate and toxicity were in the range of what was seen with continuous low-dose-rate BT.
Assuntos
Neoplasias do Ânus/radioterapia , Braquiterapia/métodos , Carcinoma de Células Escamosas/radioterapia , Recidiva Local de Neoplasia/radioterapia , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Ânus/tratamento farmacológico , Neoplasias do Ânus/patologia , Braquiterapia/efeitos adversos , Carcinoma de Células Escamosas/tratamento farmacológico , Quimiorradioterapia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Dosagem Radioterapêutica , Estudos RetrospectivosRESUMO
The end of the production of 192 iridium wires terminates low dose rate brachytherapy and requires to move towards pulsed-dose rate or high-dose rate brachytherapy. In the case of gynecological cancers, technical alternatives exist, and many teams have already taken the step of pulsed-dose rate for scientific reasons. Using a projector source is indeed a prerequisite for 3D brachytherapy, which gradually installs as a standard treatment in the treatment of cervical cancers. For other centers, this change implies beyond investments in equipment and training, organizational consequences to ensure quality.