Objective      To compare the long-term outcomes of whole lead block and partial lead block of the pelvic fields in the treatment of cervical cancer by external beam radiotherapy (EBRT) combined with californium-252 (252Cf) neutron intracavitary brachytherapy (ICBT).       Methods      From March 2007 to October 2008 and from May 2009 to December 2009

115 patients who had been diagnosed with stage ⅡA-ⅢB cervical squamous carcinoma by biopsy were enrolled and paired according to clinical stage

age

tumor size

and degree of anemia. They were divided into a whole lead block (WLB) group and a partial lead block (PLB) group during the whole pelvic field irradiation. For 252Cf ICBT

the total dose applied to point A was 40-42 Gy

9-11 Gy/f/w×4f. As for whole pelvis EBRT

anteroposterior (A-P) and posteroanterior (P-A) opposed fields were implemented. After 24-36 Gy irradiation

the pelvic field center was shielded with a 4 cm-thickness lead block in the WLB group

and the lead block was placed below S3 in the PLB group. The cumulative dose was 48-54 Gy. After EBRT

8-12 Gy irradiation should be boosted to the parametrial field if there was still parametrical invasion. McNemar test was employed to compare the severe acute complication (≥G2) incidence

overall survival rate

absolute disease-free survival rate

local control rate and severe late complication (radiation proctitis and radiation cystitis) (≥G2) incidence of the 2 groups. The mean follow-up time was 60.2 months.       Results      The incidences of acute gastrointestinal reaction

radiation proctitis

and radiation cystitis (≥G2) were higher in the WLB group than the PLB group (P0.05) though no significant difference was found. The overall survival rate

absolute disease-free survival rate

local control rate

pelvic lymph node recurrence rate and late complication incidence were higher in the WLB group thanin the PLB group. There were no statistically significant differences in the acute complication incidence

overall survival rate

absolute disease-free survival rate

local control rate

pelvic lymph node recurrence rate and late complication incidence between the 2 groups.       Conclusion      WLB of the pelvic fields has similiar efficiency as PLB in the treatment of cervical cancer by EBRT combined with 252Cf ICBT. So we recommend to employ the latter as much as possible.