Impact of dosimetric and clinical parameters on clinical side effects in cervix cancer patients treated with 3D pulse-dose-rate intracavitary brachytherapy.
OBJECTIVE
To assess the association between dosimetric/clinical parameters and gastrointestinal/urinary grade 2-4 side effects in cervix cancer patients treated with 3D pulse dose rate brachytherapy.


METHODS
Three hundred and fifty-two patients received brachytherapy associated with external-beam radiotherapy (EBRT) for 266 of them; 236 patients underwent surgery. The doses for the most exposed 2, and 0.1 cm(3) (D(2cc) and D(0.1cc)) volumes of the rectum and bladder as well as bladder ICRU point dose (D(ICRU)) were converted into isoeffective doses in 2-Gy fractions. The clinical parameters analyzed were: age, smoking habits, arteritis, diabetes, previous pelvic surgery, FIGO stage, nodal status, pathology, pelvic surgery, EBRT and chemotherapy. Side effects were prospectively assessed using the CTCAEv3.0. Cutoff dose levels were defined separately for patients treated with EBRT and brachytherapy (Group 1) and with preoperative brachytherapy (Group 2).


RESULTS
The median follow-up was 23.4months. In Group 1 a significant predictive value of rectum D(0.1cc) and D(2cc), bladder D(0.1cc) and D(ICRU) for gastrointestinal and urinary toxicity was found using as cutoff 83, 68, 109 and 68Gy(α)(/)(β)(3). In Group 2 a significant predictive value of bladder D(0.1cc), D(2cc) and D(ICRU) for urinary toxicity was found using as cutoff 141, 91 and 67Gy(α)(/)(β)(3), but not for the rectum D(0.1cc) and D(2cc); smoking had a significant predictive value on urinary toxicity.


CONCLUSIONS
For patients treated with brachytherapy and EBRT, rectum D(0.1cc) and D(2cc) and bladder D(0.1cc) and D(ICRU) had a predictive value for toxicity. For patients treated with preoperative brachytherapy, bladder D(0.1cc), D(2cc) and D(ICRU) and smoking had a predictive value for urinary toxicity.
Department of Radiotherapy, Centre Alexis-Vautrin, Vandoeuvre-les-Nancy, France; Nancy - Université, Université Paul Verlaine Metz, Université Paris Descartes, Nancy, France.
Mihai
M
Levitchi
Claire
C
Charra-Brunaud
Philippe
P
Quetin
Christine
C
Haie-Meder
Christine
C
Kerr
Bernard
B
Castelain
Martine
M
Delannes
Laurence
L
Thomas
Emmanuel
E
Desandes
Didier
D
Peiffert
D000328:Adult; D000368:Aged; D001918:Brachytherapy / Q000009:adverse effects / Q000379:methods; D005260:Female; D041981:Gastrointestinal Tract / Q000528:radiation effects; D006801:Humans; D021621:Imaging, Three-Dimensional; D053783:Magnetic Resonance Imaging, Interventional; D008875:Middle Aged; D015641:Radiography, Interventional; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D012007:Rectum / Q000528:radiation effects; D014057:Tomography, X-Ray Computed; D014551:Urinary Tract / Q000528:radiation effects; D002583:Uterine Cervical Neoplasms / Q000000981:diagnostic imaging / Q000532:radiotherapy*