[Comparison of survival and chronic gastrointestinal toxicities in patients with locally advanced cervical cancer, treated by conventional or intensity-modulated radiation technique]

Purpose: To evaluate prospectively chronic gastrointestinal toxicity in patients with cervical cancer treated with conventional irradiation or with intensity-modulated irradiation (IMRT).

Patients and methods: Between June 2005 and September 2013, 109 patients underwent external radiotherapy followed by brachytherapy for cervical cancer at the "Institut de Cancérologie de Lorraine". Each patient receiving IMRT was paired with a patient receiving conventional radiotherapy on the following criteria: concomitant chemotherapy, additional nodal dose, treatment of para-aortic lymph node area, age. The toxicity collection was prospective using the RTOG scale. The main objective was to compare the incidence of gastrointestinal toxicity chronic between the two groups. In a second time, the influence of dosimetric parameters on chronic GI toxicity was investigated. Comparisons of acute toxicity, chronic genitourinary toxicities, overall survival, disease-free survival were secondary objectives.

Results: Sixty-six patients were able to be matched. Overall survival at 36 months was 71% in the conventional radiotherapy group against 73% in the IMRT group (P=0.54). There was no significant difference between the two groups in terms of digestive chronic toxicity (P=0.17), nor in terms acute gastrointestinal toxicities (P=0.6445) and genitourinary (P=0.5724). IMRT spared significantly small bowel (P=0.0006) and rectum (P=0.0046) from 30Gy dose, and bladder from 45Gy (P<0.001). The incidence of genitourinary toxicity was significantly different between the two groups (P=0.03) in favor of conventional radiotherapy.

Conclusion: Our study does not seem to show significant difference in the occurrence of chronic gastrointestinal toxicities between the two groups. Clinical efficacy seems comparable. Larger studies with longer follow-up period should be conducted.