A new prognostic index (CLIPI) for advanced cutaneous lymphoma enables precise patient risk stratification

Advanced mycosis fungoides (MF) and Sézary syndrome (SS) have a poor overall survival (OS) of <5yrs. Studies have found the current staging (IA-IVB) is inadequate for risk stratification. The PROCLIPI (Prospective Cutaneous Lymphoma International Prognostic Index) study was launched in 2015 at 46 international expert MF/SS centers, prospectively collecting predefined datasets in patients with newly diagnosed MF/SS, to determine a cutaneous lymphoma IPI (CLIPI). 552 patients with advanced stage MF/SS were recruited. The 5-year OS for stage IIB was 50.0%, IIIA=64.8%, IIIB=43.9%, IVA1=50.8%, IVA2=25.9%, and IVB=36.9%. Factors at diagnosis associated with a significantly worse survival were N3 status (P<0.001), age>60yrs (P<0.001), raised serum lactate dehydrogenase (P=0.005), and large-cell transformation in skin (P=0.006). Modelling these 4 independent risk-factors into a CLIPI found that there was a worse OS in high vs low-risk (P<0.001), high vs intermediate-risk (P=0.002) and intermediate vs low-risk (P=0.010). Five-year OS were 63.3%, 44.7%, and 18.3% in the low-, intermediate-, and high-risk groups. In this advanced stage cohort there was a low 5-year survival and increasing stage wasn't associated with worsening survival. The use of CLIPI to stratify patients into risk groups, has the potential to improve outcomes and aid optimal treatment selection. This trial was registered at www.ClinicalTrials.gov as #NCT02848274.