[Contribution of whole-body MRI to the initial assessment of myxoid liposarcoma]. / Apport de l'IRM corps entier au bilan initial du liposarcome myxoïde.

INTRODUCTION: Myxoid liposarcoma is a soft tissue sarcoma associated with multifocal metastases at diagnosis. These metastases are asymptomatic and occult on CT and FDG-PET and can alter the therapeutic management and prognosis. In this context, we evaluated the contribution of whole-body MRI to the initial workup of patients with myxoid liposarcoma. METHOD: This retrospective study was conducted between January 2015 and December 2020 at the Oscar Lambret Center. We enrolled 22 patients who were diagnosed with myxoid liposarcoma and underwent whole-body MRI at diagnosis. The number of metastases at diagnosis, their location, and the visibility of these lesions on CT were evaluated. Associations between clinical features, presence of metastasis, and their impact on management were assessed. RESULTS: Sixteen patients (72.7%) had non-metastatic disease at the initial diagnosis, and 15 of these patients were managed using local treatment. Six patients (27.3%) had metastases at multiple locations and received chemotherapy. The main locations were the bones (n=5) and lungs (n=3). In five patients with metastases, whole-body MRI demonstrated additional lesions that were not visible on CT (bone and soft tissue lesions). Only the presence of a round cell contingent (P=0.009) was found as a criterion associated with the presence of metastases. CONCLUSION: The patients' young age, absence of reliable prognostic factors at diagnosis, asymptomatic nature of the lesions, and the benefits of early and targeted therapeutic management encourage the use of whole-body MRI as part of the initial work-up as it seems to provide a better initial staging compared with conventional imaging.

Prognostic impact of tumor size reduction assessed by magnetic resonance imaging after radiochemotherapy in patients with locally advanced cervical cancer.

Objective: Pelvic magnetic resonance imaging (MRI) is a key exam used for the initial assessment of loco-regional involvement of cervical cancer. In patients with locally advanced cervical cancer, MRI is used to evaluate the early response to radiochemotherapy before image-guided brachytherapy, the prognostic impact of which we aimed to study. Methods: Patients with locally advanced cervical cancer treated using concomitant radiochemotherapy followed by closure treatment between January 2010 and December 2015 were included in this study. Clinical, anatomopathological, radiological, therapeutic, and follow-up data were evaluated. Results: After applying the inclusion and exclusion criteria to the initially chosen 310 patients, 232 were included for evaluation (median follow-up period, 5.3 years). The median age was 50 years (range, 25-83 years), and the median tumor size was 47.5 mm (range, 0-105 mm). Based on the International Federation of Gynaecology and Obstetrics classification system, 9 patients were in stage IB2; 20, IB3; 2, IIA; 63, IIB; 4, IIIA; 7, IIIB; and 127, IIIC1 or higher. The re-evaluation MRI was performed at the median dose of 55.5 Gy, and median reduction in tumor size was 55.2% (range, -20-100%). There was a difference between the disease-free and overall survival rates of the patients with a tumor response greater or lesser than 50%. The risk of recurrence or death reduced by 39% in patients with a tumor size reduction >50%. The overall 5-year survival rate of patients with a response greater and lesser than 50% were 77.7% and 61.5%, respectively. The 5-year disease-free survival rate for these two groups of patients were 68.8% and 51.5%, respectively. Conclusion: Our study confirms the prognostic impact of tumor size reduction using MRI data obtained after radiochemotherapy in patients with locally advanced cervical cancer.