Clinical outcomes of definitive chemoradiation followed by intracavitary pulsed-dose rate image-guided adaptive brachytherapy in locally advanced cervical cancer.

OBJECTIVE: To report the outcomes and late toxicities of patients with locally advanced cervical cancer treated with concomitant chemoradiation (CRT) followed by intracavitary image-guided adaptive brachytherapy (IGABT). METHODS: Data from consecutive patients with histologically proven stage IB-IVA cervical cancer treated with curative intent in a single institution were analyzed. After pelvic +/- para-aortic external-beam radiation therapy, they received pulsed-dose rate IGABT following GEC-ESTRO recommendations. RESULTS: Two hundred and twenty-five patients were enrolled. Sixty-five percent were stage≥IIB according to FIGO classification. Ninety-five percent received CRT. Mean D90 to HR and IR-CTV were 80.4+/-10.3Gy and 67.7+/-6.1Gy. After a median follow-up of 38.8months, 3-year local control and overall survival rates were 86.4% and 76.1%, respectively. A trend for a detrimental effect of tumor stage on local control rates was observed with 3-year local control rates of 100% for stages IB1 and IIA, 90.5 for IB2, 85.8% for IIB, 50% for IIIA, 77.1 for IIIB, and 66.7% for IVA tumors (p=0.06). Local control rates at 3years were 95.6% in the group of patients with D90 of HR-CTV≥85Gy, 88.8% in those with D90 between 80 and 85Gy, and 80% when D90<80Gy (p=0.018). Eighteen severe late gastrointestinal and urinary effects affecting 14 patients were reported corresponding with a crude incidence of 6.6%. CONCLUSIONS: CRT followed by IGABT provides high local control rates with limited toxicity. Reaching high doses is mandatory to achieve local control and interstitial brachytherapy is necessary in advanced diseases.

Image-guided adaptive brachytherapy in cervical cancer: Patterns of relapse by brachytherapy planning parameters.

PURPOSE: Cervical cancer patients with a bulky high-risk clinical target volume (HR-CTV) get the largest benefit of dose escalation in terms of local control. However, the expected survival benefit could be lessened by a higher metastatic risk. We examined the patterns of relapse according to major prognostic factors: the HR-CTV volume and to the D90 HR-CTV. METHODS AND MATERIALS: The clinical records of patients treated with pulsed-dose-rate image-guided adaptive brachytherapy after concurrent pelvic chemoradiation were reviewed. All patients had an optimal workup before treatment comprising a 18-fluorodeoxyglucose positron emission tomography/computed tomography and a para-aortic lymph node dissection. Patients with initial extrapelvic disease were excluded. RESULTS: A total of 109 patients fulfilled inclusion criteria. Median followup was 39 months. An HR-CTV volume ≥40 cm(3) was associated with a poorer local failure-free survival. There was a strong inverse correlation between the HR-CTV volume and the D90 of the HR-CTV (correlation coefficient r = -0.696; p < 0.001) with increasing HR-CTV volume being associated with a decreasing D90 HR-CTV. A D90 HR-CTV <85 Gy and an HR-CTV volume ≥40 cm(3) were significant univariate factors for experiencing nonlocal failure (p = 0.002 and 0.035, respectively), even after exclusion of local relapses. CONCLUSION: A lower ability to reach the target D90 HR-CTV planning and an HR-CTV volume ≥ 40 cm(3) correlated with a high propensity of relapsing at distance, these factors being interrelated. Next step of treatment personalization should design strategies integrating this risk, which is now the main cause of failure.