HDR brachytherapy applied to cervical carcinoma with moderate lateral expansion: modified principles of treatment.
OBJECTIVE
In order to meet the deficiencies of endocavitary applications, a combined technique was introduced with the aim of achieving better target coverage for improvement of loco-regional tumour control. In high dose rate (HDR) endocavitary applications with tandem and ovoids, enlargement of the distance between the ovoids, shifting of dwell times and also optimization often fail to achieve sufficient expansion of the cervical parametrial area encompassed by the reference isodose.


METHODS
The Deventer method, whereby HDR endocavitary and HDR interstitial brachytherapy are applied in the same session, was applied for tumours with a lateral expansion of 25 mm or more from the axis of the cervical canal. For the addition of HDR interstitial brachytherapy, each ovoid was provided with a channel which allowed insertion of an afterloading needle into the cervix up to a fixed depth. The dose specifications and dosimetry in neighbouring organs are presented in detail.


RESULTS
Seventy-six combined applications were given to 41 patients. The follow-up averaged at 23 months, with a maximum of 59 months. No severe early or persistent late complications were observed. In stage IIB tumours, the most important evaluation of the merits of this technique, the disease-free 3-year survival determined with the Kaplan-Meier method was 75% (n=20).


CONCLUSIONS
The Deventer method of HDR endocavitary and HDR interstitial brachytherapy applied in the same session is a feasible method for enlargement of the reference isodose envelope in the cervical parametrial area. The 3-year disease-free survival in stage IIB patients and the low complication rates in all stages together, justify its continuation.
Kuipers
T
T
R.I.S.O., Institute for Radiotherapy and Curietherapy, H.J.P. Fesevurstraat 11, 7415 CM, The, Deventer, Netherlands.
Hoekstra
C J
CJ
van 't Riet
A
A
Mak
A C
AC
Vonk
E J
EJ
Elders
L H
LH
Koster
K
K
Pop
L A
LA
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007496:Iridium Radioisotopes / Q000627:therapeutic use; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology; D009367:Neoplasm Staging; D010020:Osteonecrosis / Q000209:etiology; D011350:Proctocolitis / Q000209:etiology; D011832:Radiation Injuries / Q000209:etiology; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods; D002583:Uterine Cervical Neoplasms / Q000473:pathology / Q000532:radiotherapy*
D007496:Iridium Radioisotopes