Pulsed dose rate brachytherapy in head and neck cancers. Feasibility study of a French cooperative group.
OBJECTIVE
To prospectively evaluate the feasibility of pulsed dose rate (PDR) brachytherapy to mimic the continuous low dose rate (cLDR) iridium wire technique in head and neck carcinomas.


METHODS
A series of 30 patients were included from June 1995 to May 1998. The primaries were located in the oral cavity (four T1, seven T2 and two T3), the velotonsillar arch (eight T1 and eight T2) and the posterior wall (one T3). Thirteen were irradiated by exclusive brachytherapy (dose, > or =45 Gy). The PDR delivered 0.5 Gy/pulse, one pulse/h, day and night, to mimic cLDR irradiation.


RESULTS
The implantation was feasible for all the patients, usually easy and of good quality. The mean duration/pulse was 13 min, with a mean source activity of 171 mCi. Patient tolerance was poor in nine cases. Sixteen patients could receive the whole PDR treatment with a total ranging from 30 to 120 pulses without any problem. Seven had short breakdowns (< or =6 h). Seven had definitive breakdowns, but could end the irradiation by manual afterloading of iridium 192 wires. The radioprotection was better (or complete), except for one patient. Most of the breakdowns were related to kinking or flattering of the tube.


CONCLUSIONS
PDR is feasible in head and neck carcinomas, but necessitates improvement of the quality and control of the plastic tubes.
Peiffert
D
D
Centre Alexis Vautrin, Ave. de Bourgogne, 54511 Cedex, Vantoeuvre-lès-Nancy, France.
Castelain
B
B
Thomas
L
L
Ardiet
J M
JM
Baillet
F
F
Mazeron
J J
JJ
D001918:Brachytherapy / Q000009:adverse effects / Q000379:methods*; D002294:Carcinoma, Squamous Cell / Q000532:radiotherapy*; D004307:Dose-Response Relationship, Radiation; D005240:Feasibility Studies; D006258:Head and Neck Neoplasms / Q000532:radiotherapy*; D006801:Humans; D007496:Iridium Radioisotopes / Q000627:therapeutic use; D011446:Prospective Studies; D011879:Radiotherapy Dosage
D007496:Iridium Radioisotopes