Three or four fractions of 4-5 Gy per week in postoperative high-dose-rate brachytherapy for endometrial carcinoma.
OBJECTIVE
To evaluate the results of high-dose-rate brachytherapy (HDRBT) using a schedule of three or four fractions per week, when possible, in 89 patients on local control and toxicity in postoperative treatment of endometrial carcinoma. The effect of the overall HDRBT treatment time (OTT) on toxicity was also evaluated.


METHODS
Fédération Internationale de Gynécologie Obstétrique Stage: 24 IB, 45 IC, 4 IIA, 6 IIB, 4 IIIA, 2 IIIB, and 4 IIIC. Radiotherapy: Group 1-67 of 89 patients received external beam irradiation (EBI; 44-50 Gy) plus HDRBT (3 fractions of 4-6 Gy); Group 2-22 of 89 patients received HDRBT alone (6 fractions of 4-5 Gy). OTT: Group 1-HDRBT was completed in a median of 5 days in 32 patients and in >5 days in 35; Group 2-HDRBT was completed in <15 days in 11 patients and in ≥16 days in 11. Toxicity was evaluated using Radiation Therapy Oncology Group scores and the bioequivalent dose (BED) study was performed in vaginal mucosa surface. Statistics included Student's t test, chi-square test, and receiving operator curves.


RESULTS
With a mean follow-up of 31 months (range, 6-70), 1 of 89 patients had vaginal relapse. Early toxicity appeared in 8 of 89 (9%) patients and was resolved. Late toxicity appeared in 13/89 (14%): vaginal nine Grade 1, three Grade 2, one Grade 4; bladder two Grade 2; rectal three Grade 1, one Grade 2. No differences were found in relation to OTT in Groups 1 and 2. Mean BED was 88.48 Gy in Group 1 and 165.28 Gy in Group 2. Cases with Grade 2 late vaginal toxicity received >75 Gy after EBI and >165 Gy in Group 2.


CONCLUSIONS
Three fractions of 4-5 Gy in 3-5 days after EBI or 6 fractions in <15 days in patients receiving HDRBT alone was a safe treatment in relation to toxicity and local control. Vaginal surface BED less than 75 Gy after EBI and less than 160 Gy in HDRBT alone may be safe to avoid G2 toxicity.
Rovirosa
Angeles
A
Radiation Oncology Department, Hospital Clinic, Institut d'Investicació Biomédica Agustí Pi i Sunyer, Barcelona, Spain. rovirosa@clinic.ub.es
Ascaso
Carlos
C
Sánchez-Reyes
Alberto
A
Herreros
Antonio
A
Abellana
Rosa
R
Pahisa
Jaume
J
Lejarcegui
Jose Antonio
JA
Biete
Albert
A
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy / Q000009:adverse effects / Q000379:methods*; D019583:Dose Fractionation, Radiation; D016889:Endometrial Neoplasms / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D009367:Neoplasm Staging / Q000379:methods; D011832:Radiation Injuries / Q000473:pathology; D012189:Retrospective Studies; D013997:Time Factors; D001743:Urinary Bladder / Q000528:radiation effects; D014621:Vagina / Q000528:radiation effects; D014625:Vaginal Neoplasms / Q000556:secondary