Session Item

Retrospective evaluation of the outcomes and late gastrointestinal (GI) and genitourinal (GU) toxicity regarding to dose reduction in curative chemoradiation of cervical cancer.

Between October 2002 and March 2017, 390 patients with FIGO stage IB2-IVA cervical cancer were treated with 45 or 50.4 Gy conventional three-dimensional conformal external beam radiation therapy (EBRT) and intracavitary high-dose-rate brachytherapy (BT) with doses either 3x7 Gy or 4x7 Gy. The predictors of treatment outcome were evaluated with Cox-regression, while logistic regression was used to determine the effect of the dose on late GI and GU toxicity.

The median follow-up time was 54 months (range 2-204 months). The 10-year overall survival (OS), disease-free survival (DFS), locoregional relapse-free survival (LRFS) and metastases-free survival (MFS) were 39.4%, 39.5%, 40.3% and 40.4%, respectively. Patients with bulky primary tumour (>4 cm) and positive lymph node (pelvic with or without paraaortic) status treated with 50.4 Gy EBRT and 4x7 Gy BT showed better outcomes compared with the group of patients received 3x7 Gy BT: LRFS was 55.1% and 53.8% (p=0.0485), DFS was 52.8% vs. 47.9% (p=0.0026) and OS was 62.3% vs. 46.1% (p=0.0199) in 4x7 Gy versus 3x7 Gy BT groups.

Cumulative grade 0 GI toxicity occurred in 65.1%, grade 1 in 13.3%, grade 2 in 12.4%, grade 3 in 7.6% and grade 4 in 1.6% of the patients. Small bowel resection was performed in 23 patients (5.8%) due to grade 3-4 toxicity. 7.9% of the survivors (36 patients) still have late grade 1-2 GI toxicity.

Referring to late GU toxicity, 79.3% of the patients reported grade 0 toxicity, 8.1% of the patients had grade 1, 11.0% had grade 2 and 1.6% had grade 3 events. Grade 4 GU toxicity was not registered. Persistent grade 1-2 incontinence still occurs in 11% (32 patients) and one patient had grade 3 incontinence.

Neither the dose of the EBRT, BT nor the equivalent dose at fractionation of 2 Gy took effect on the rate of the late GI and GU toxicity.

Treating with higher dose of brachytherapy resulted in significantly better outcomes only in the group of patients with bulky primary tumour and node positive cervical cancer, however our results did not show correlation between the dose of the radiotherapy and late toxicity.