Intensity-modulated radiation therapy versus three-dimensional conformal radiation therapy with concurrent nedaplatin-based chemotherapy after radical hysterectomy for uterine cervical cancer: comparison of outcomes, complications, and dose-volume histogram parameters

BACKGROUND The purpose of this study is to report our clinical outcomes using intensity-modulated radiation therapy (IMRT) for adjuvant treatment of cervical cancer, compared with three-dimensional conformal radiation therapy (3DCRT), in terms of tumor control, complications and dose-volume histogram (DVH) parameters. METHODS Between March 2008 and February 2014, 62 patients were treated with concurrent nedaplatin-based chemotherapy and whole-pelvic external beam radiation therapy (RT). Of these patients, 32 (52%) received 3DCRT and 30 (48%) received IMRT. RESULTS The median follow-up periods were 40 months (range 2-74 months). The 3-year overall survival rate (OS), locoregional control rate (LRC) and progression-free survival rate (PFS) were 92, 95 and 92% in the IMRT group, and 85, 82 and 70% in the 3DCRT group, respectively. A comparison of OS, LRC and PFS showed no significant differences between IMRT and 3DCRT. The 3-year cumulative incidences of grade 2 or higher chronic gastrointestinal (GI) complications were significantly lower with IMRT compared to 3DCRT (3% vs. 45%, p < .02) and in patients with V40 of the small bowel loops of ≤340 mL compared to those with >340 mL (3% vs. 45%, p < .001). Patients treated with IMRT had a higher incidence of grade 3 acute hematologic complications (p < .05). V40 and V45 of the small bowel loops or bowel bag were predictive for development of both acute and chronic GI complications. CONCLUSIONS Our results suggest that IMRT for adjuvant treatment of cervical cancer is useful for decreasing GI complications without worsening outcomes.