Transperineal high-dose-rate interstitial radiation therapy in the management of gynecologic malignancies.
BACKGROUND
High-dose-rate interstitial radiation therapy is a newly introduced modality, and its role in the management of gynecologic malignancies remains to be studied. Clinical experience in high-dose-rate interstitial radiation therapy was retrospectively investigated.


METHODS
Eight patients with primary and nine with recurrent gynecologic malignancies underwent high-dose-rate interstitial radiation therapy with/without external-beam irradiation. Fractional dose of the high-dose-rate interstitial radiation therapy ranged between 4 and 6 Gy with total doses of 15-54 Gy. Interstitial irradiation was performed twice daily with an interval of > 6 h.


RESULTS
2-year local control rate was 75% for primary treatment and 47% for treatment of recurrence (p = 0.46). Maximum tumor size had a statistically significant impact on local control (p < 0.002). Grade 2 and 4 late complications were seen in five patients, and the incidence was significantly higher in patients with a larger volume enclosed by the prescribed fractional dose of high-dose-rate interstitial radiation therapy. The incidence of grade 2 and 4 complications at 18 months was 78% and 0% with a volume > 100 cm(3) and < or = 100 cm(3), respectively (p < 0.04).


CONCLUSIONS
Although high-dose-rate interstitial radiation therapy is a promising modality, it must be applied cautiously to patients with bulky tumors because of the high incidence of serious complications.
Itami
Jun
J
Department of Radiation Therapy and Oncology, International Medical Center of Japan, Tokyo, Japan. jitami@imcj.hosp.go.jp
Hara
Ryusuke
R
Kozuka
Takuyou
T
Yamashita
Hideomi
H
Nakajima
Kaori
K
Shibata
Kouji
K
Abe
Yoshihisa
Y
Fuse
Masashi
M
Ito
Masashi
M
D000230:Adenocarcinoma / Q000401:mortality / Q000532:radiotherapy*; D000368:Aged; D001918:Brachytherapy / Q000009:adverse effects; D002294:Carcinoma, Squamous Cell / Q000401:mortality / Q000532:radiotherapy*; D002296:Carcinosarcoma / Q000401:mortality / Q000532:radiotherapy*; D003627:Data Interpretation, Statistical; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000532:radiotherapy; D010051:Ovarian Neoplasms / Q000401:mortality / Q000532:radiotherapy*; D010502:Perineum; D011879:Radiotherapy Dosage; D012189:Retrospective Studies; D016019:Survival Analysis; D013997:Time Factors; D002583:Uterine Cervical Neoplasms / Q000401:mortality / Q000532:radiotherapy*; D014625:Vaginal Neoplasms / Q000401:mortality / Q000532:radiotherapy*