Increased Occurrence of Malignancy Before and after Chemoradiation for Anal Squamous Cell Carcinoma: A Multi-Institutional Analysis

Menée à l'aide de données multicentriques portant sur 647 patients atteints d'un cancer épidermoïde de l'anus traité par chimioradiothérapie (72 % de femmes ; âge médian : 61 ans), cette étude identifie des facteurs associés à l'incidence de tumeurs malignes multiples avant ou après le traitement puis évalue leur effet sur la survie

Résumé en anglais

Anal squamous cell carcinoma (ASCC) is a rare cancer with increased occurrence of multiple cancers before and after the ASCC diagnosis. However, there is limited data on this aspect. This multi-institutional analysis aimed to define the occurrence of malignancies before and after ASCC, time trends, impact on survival, and identify prognostic factors.Initial primary malignancy (IPM) was defined as a malignancy occurring before the ASCC. Second primary malignancy (SPM) was defined as a distinct primary cancer that developed after ASCC diagnosis. Retrospective multi-institutional chart review was done. Progression free survival (PFS), overall survival (OS) and prognostic factors were evaluated.647 patients with ASCC treated with curative intent were analyzed. Median age was 61.23 years with 72% as females. 150 patients (23.3%) had multiple malignancies with IPM in 16% and SPM in 8%. Patients without prior cancer had better 5-year PFS (81.2% vs 67.2%, p = .011) and OS (81% vs 69%, p = .008) compared to those with prior cancer. SPMs had a significant adverse impact on PFS (HR 4.22) and OS (HR 3.56). Females had better 5-year PFS (82% vs 70%, p = .016) as compared to males. The median time interval for developing ASCC (as SPM) after IPM was 9.32 years.ASCC patients have increased risk of multiple malignancies. Patients with prior cancer have inferior outcomes. SPM is a poor prognostic factor in patients without any prior cancer. SPM can develop years after treatment of primary ASCC.