Twice-daily fractionation of external irradiation with brachytherapy in bulky carcinoma of the cervix. Phase I/II study of the Radiation Therapy Oncology Group 88-05.
BACKGROUND
Hyperfractionated radiation therapy (HFX), which may permit higher total doses of radiation therapy without increased toxic effects to normal tissues, has been used with pelvic tumors, but its combination with brachytherapy has not been well studied.


METHODS
A prospective Phase I/II trial was designed to study HFX with brachytherapy in patients with bulky Stage IB and IIA, IIB, III, and IVA carcinomas of the cervix. HFX doses of 1.2 Gy were administered to the whole pelvis twice daily at 4-6 hour intervals, 5 days per week; the total dose to the whole pelvis was 24-48 Gy. External pelvic irradiation was followed by one or two intracavitary applications to deliver the total minimum dose of 85 Gy at point A and 65 Gy to the lateral pelvic nodes.


RESULTS
Eighty-one patients were enrolled in this protocol; 14% had Stage IB, 43% stage II, 38% stage III, and 4% stage IVA carcinomas. Seventy-one patients were evaluable for HFX and brachytherapy; 38 patients received one intracavitary application, and 33 received two applications. Four patients had Grade 3 acute reactions. The cumulative rates of Grade 3-4 late toxicities were 1.9% at 1 year, and 6.3% at 2 and 3 years. Of 80 patients evaluated for response, 80% had complete disappearance of disease. Comparisons with historical rates of late toxicity with standard fractionation (STD) revealed similar results in spite of higher total doses with HFX. Comparisons between historical STD and HFX also revealed equivalent rates of pelvic tumor control, Grade 3-4 toxicity, and survival at 3 years.


CONCLUSIONS
Results suggest that combined with brachytherapy, HFX at total parametrial doses 10% above those used with STD was tolerated and at least as effective as STD. Further study with higher doses and extended fields is indicated. Comparisons of long term (5-plus years) survival and late-effects rates with STD versus HFX are planned.
Komaki
R
R
Department of Radiotherapy, University of Texas M. D. Anderson Cancer Center, Houston 77030.
Pajak
T F
TF
Marcial
V A
VA
Rotman
M
M
Grigsby
P W
PW
Leibel
S A
SA
Eifel
P J
PJ
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy; D005260:Female; D006801:Humans; D008875:Middle Aged; D011446:Prospective Studies; D011879:Radiotherapy Dosage; D002583:Uterine Cervical Neoplasms / Q000401:mortality / Q000532:radiotherapy*