ABSTRACT
BACKGROUND: Mycosis fungoides (MF) has usually an indolent course. However, some patients develop a more aggressive disease and few prognostic parameters have been identified. Isolated cases of pustular MF (pMF) suggest an unfavourable prognosis. OBJECTIVES: We aim to describe the clinico-pathological characteristics and prognostic value of pMF. METHODS: We retrospectively collected data of all cases of MF with histological pustules diagnosed from 2009 to 2020. The outcomes and clinico-pathological characteristics of pMF at diagnosis (pMFD) were compared to those of a cohort of non-pustular MF (NpMF). RESULTS: 33 pMF (including 22 pMFD) and 86 NpMF cases were included. The median age at diagnosis of pMF was 61 years [IQR=50-75]. The median follow-up of pMFD was 32 months [IQR=14-49]. Clinically, 33% of pMF had pustules. Large-cell transformation (LCT) occurred in 17 cases. pMFD were at a significantly more advanced-stage and more showed LCT at diagnosis than NpMF (50% vs 7%, p<0.001 and 23% vs 0%, p<0.001, respectively). In multivariate Cox analysis, the presence of histological pustule at diagnostic was associated with shorter OS in all patients (HR=13.90, CI95%[2.43-79]; p=0.003), and in early-stage patients (HR=11.09, CI95%[1.56-78.82]; p=0.02). In multivariate Fine and Gray model analysis, pMFD was associated with a higher cumulative incidence of LCT (SHR=13.90, CI95% [2.43-79]; p=0.003) in all patients. Median OS after the occurrence of histological pustules during follow-up of all pMF patients was 37 months, with a five-year OS of 25% (CI95% [0.06-0.5]). CONCLUSION: pMF often follows an aggressive course, with a high risk of LCT and shorter survival, even for early-stage patients. Histological pustules at diagnostic of MF might represent an independent poor prognostic factor, to be confirmed by further studies. Because pustules are not always clinically identified, histological pustules should be mentioned in pathology reports of MF and prompt discussion of a closer follow-up.
Subject(s)
Antifungal Agents , Axilla , Paracoccidioidomycosis , Humans , Antifungal Agents/therapeutic use , Antifungal Agents/administration & dosage , Paracoccidioides/isolation & purification , Paracoccidioidomycosis/diagnosis , Paracoccidioidomycosis/drug therapy , Skin/pathology , Skin/microbiologyABSTRACT
Malignant peripheral nerve sheath tumors (MPNSTs) are the leading cause of death in patients with neurofibromatosis type 1. They can result from premalignant neurofibromas, including neurofibromas with atypia and atypical neurofibromatous neoplasms of uncertain biologic potential. Some phenotypic characteristics have been described as associated with their development. The aim of this study was to outline our use of whole-body positron emission tomography with 18F-fluorodeoxyglucose/magnetic resonance imaging in adults with neurofibromatosis type 1, especially in the screening of asymptomatic individuals with a higher risk of developing an MPNST, and to study its impact on neurofibroma classification (malignant vs premalignant) and MPNST staging over time. Individuals with neurofibromatosis type 1 who underwent a positron emission tomography with 18F-fluorodeoxyglucose/magnetic resonance imaging between 2017 and 2021 were included, analyzing separately the screened population. Maximum standard uptake value and diffusion-weighted imaging were assessed. Biopsy/surgery confirmed the diagnosis. In all, 345 positron emission tomography with 18F-fluorodeoxyglucose/magnetic resonance imaging were performed in 241 patients, including 149 asymptomatic (62%) but at-risk patients. Eight MPNSTs in 8 screened individuals (5%), 6 neurofibromas with atypia in 4 individuals (3%), and 29 atypical neurofibromatous neoplasms of uncertain biologic potential in 23 individuals (15%) were diagnosed. Over time, the proportion of grade 3 MPNST and the malignant/premalignant ratio in screened individuals significantly decreased (P = .03 and P < .001, respectively). This study emphasizes the diagnostic and screening performances of whole-body positron emission tomography with 18F-fluorodeoxyglucose/magnetic resonance imaging in adults with neurofibromatosis type 1.