Prognostic Impact of Pretherapeutic FDG-PET in Localized Anal Cancer

Maëlle Le Thiec (1) , Aude Testard (2) , Ludovic Ferrer (3, 4) , Camille Guillerminet (5) , Olivier Morel (2) , Bruno Maucherat (1) , Daniela Rusu (1) , Sylvie Girault (2) , Marie Lacombe (2) , Hadji Hamidou (6) , Véronique Guérin Meyer (7) , Emmanuel Rio (8) , Sandrine Hiret (9) , Françoise Kraeber-Bodéré (3, 1) , Loïc Campion (10) , Caroline Rousseau (3, 1)

1 Service de médecine nucléaire [Saint-Herblain]
2 Département de Médecine Nucléaire [Angers]
3 CRCINA-ÉQUIPE 13 - Nuclear Oncology
4 Département de Physique Médicale [Saint-Herblain]
5 Département de Physique Médicale [Angers]
6 Service de la Radio-Oncologie [Angers]
7 Service Oncologie Médicale [Angers]
8 Service de la Radio-Oncologie [Saint-Herblain]
9 Centre René Gauducheau - ICO - Département d'oncologie médicale [Saint Herblain]
10 CRCINA-ÉQUIPE 11 - Integrative Oncogenomics of Multiple Myeloma Pathogenesis and Progression

Due to the heterogeneity of tumour mass segmentation methods and lack of consensus, our study evaluated the prognostic value of pretherapeutic positron emission tomography with fluorodeoxyglucose (FDG-PET) metabolic parameters using different segmentation methods in patients with localized anal squamous cell carcinoma (SCC). Eighty-one patients with FDG-PET before radiochemotherapy were retrospectively analyzed. Semiquantitative data were measured with three fixed thresholds (35%, 41% and 50% of Maximum Standardized Uptake Value (SUVmax)) and four segmentation methods based on iterative approaches (Black, Adaptive, Nestle and Fitting). Metabolic volumes of primary anal tumour (P-MTV) and total tumour load (T-MTV: P-MTV+ lymph node MTV) were calculated. The primary endpoint was event-free survival (EFS). Seven multivariate models were created to compare FDG-PET tumour volumes prognostic impact. For all segmentation thresholds, PET metabolic volume parameters were independent prognostic factor and T-MTV variable was consistently better associated with EFS than P-MTV. Patient's sex was an independent variable and significantly correlated with EFS. With fixed threshold segmentation methods, 35% of SUVmax threshold seemed better correlated with EFS and the best cutoff for discrimination between a low and high risk of event occurrence was 40 cm 3. Determination of T-MTV by FDG-PET using fixed threshold segmentation is useful for predicting EFS for primary anal SCC. If these data are confirmed in larger studies, FDG-PET could contribute to individualized patient therapies.

Mots clés: anal cancer; FDG-PET; prognosis; metabolic tumour volume

Domaines: Cancer

Maëlle Le Thiec, Aude Testard, Ludovic Ferrer, Camille Guillerminet, Olivier Morel, et al.. Prognostic Impact of Pretherapeutic FDG-PET in Localized Anal Cancer. Cancers, 2020, 12 (6), pp.1512. ⟨10.3390/cancers12061512⟩. ⟨inserm-02908736⟩