Blastic Plasmocytoid Dendritic Cell Neoplasm (BPDCN): Clinical Features and Histopathology with a Therapeutic Overview.

Blastic Plasmacytoid Dendritic Cell Neoplasms (BPDCNs) are a rare, highly aggressive hematological malignant neoplasm that primarily involve the skin, bone marrow, lymph nodes and even extra-nodal sites. The rarity and relative poor description of cases in the literature make it necessary to review and further studies that deeply investigate this entity not only in a histopathological but also molecular field. In August-September 2023, we searched MEDLINE, PubMed and Scopus for randomized controlled trials (RCTs), narrative and systematic reviews, meta-analyses, observational studies (either longitudinal or retrospective), and case series published in English in the last 25 years using the keywords BPDCN, PDCs, Blastic NK-cell lymphoma, agranular CD4+ NK leukemia/lymphoma, agranular CD4+ CD56+ hematodermic neoplasm/tumor. Despite the progress made in recent years in the diagnosis and biological understanding of the disease, until 2018 there was no clear consensus regarding its treatment and the main therapeutic schemes used were based on chemotherapy regimens already used in the treatment of lymphomas, acute lymphoblastic leukemia (ALL) and/or acute myeloid leukemia (AML). In this narrative review, we address the definition and epidemiological features of BPDCN, provide the different theories on the etiopathogenesis with particular attention to the presumed cell of origin, discuss the main clinical manifestations that provide a sign of its presence, summarize the main histopathological and immunophenotypic characteristics with special attention to the most important markers, and finally, we provide some of the most effective information on the therapeutic treatment modalities of BPDCN.

Laminar Necrosis and Hypoxic Damage of the Placenta: A Case-Control Study.

The aim of this study is to verify the role of laminar necrosis (LN) in the diagnosis of hypoxic damage of the placenta. This is a retrospective case-control study in which 50 cases with laminar necrosis were compared with 100 gestational age-matched controls without laminar necrosis in a 1:2 ratio. The parameters analyzed were: the presence of other placental lesions, obstetric characteristics and neonatal outcome. For each of the 50 cases, the area affected by the lesion was detected, and the lesions were classified into three groups based on the morphology and time of onset of the lesion in order to understand whether these characteristics of the lesion had a clinical-pathology. The results showed that including the search for LN among placental lesions generally examined is useful to guide the pathologist in the diagnosis of placental dysfunction of hypoxic origin.

Preferentially Expressed Antigen in Melanoma (PRAME) and Human Malignant Melanoma: A Retrospective Study.

BACKGROUND: Preferentially expressed antigen in melanoma (PRAME) is a cancer testis antigen (CTA) identified in 1997 through analysis of the specificity of tumor-reactive T-cell clones derived from a patient with metastatic cutaneous melanoma. Although at first it seemed even more specific, various studies have shown that PRAME can also be expressed in the context of atypical lesions that do not correspond solely to the definition of malignant melanoma. METHODS: A systematic review of English articles was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. RESULTS: 126 records were identified in the literature search, of which 9 were duplicates. After screening for eligibility and inclusion criteria, 53 publications were included. CONCLUSIONS: The advent of a new marker such as PRAME is surely a step forward not only in the diagnostic approach, but also in the immunotherapeutic approach to MM. However, various studies have shown that PRAME can also be expressed in the context of atypical lesions apart from MM and, for this reason, the diagnostic sensitivity and specificity (hence accuracy) are clearly lower. Further studies with larger case series will be necessary to understand better what possibilities are offered in terms of diagnostic reliability by PRAME.