Neurofibromatosis type 1 (NF1) is a neurocutaneous syndrome, due to heterozygous pathogenic variants in NF1 gene. The main clinical manifestations are multiple café au lait spots, axillary and inguinal freckling, cutaneous and plexiform neurofibromas, optic glioma, Lisch nodules and osseous lesions, such as sphenoid and tibial dysplasia. Vasculopathy is another feature of NF1; it consists of stenosis, aneurysms, and arteriovenous malformations, frequently involving renal arteries. We report on a 9-year-old girl with a novel mutation in NF1 gene and renal artery aneurysm, treated by coil embolization and complicated with hypertension. Vasculopathy is a complication of NF1, affecting from 0.4 to 6.4% of patients with NF1. Among the vascular abnormalities, renal artery aneurysm is a rare manifestation, with only a few cases regarding adult patients and no pediatric reports described in current literature. The finding of a vascular abnormality in a specific site requires the evaluation of the entire vascular system because multiple vessels could be involved at the same time.

Hemolytic anemia could be caused by several conditions, depending on intrinsic or extrinsic defects of the erythrocyte. The latter group includes mechanical intravascular hemolysis, generally related to malfunctioning prosthetic heart valves or, rarely, heart valves repair. We describe a case of a child with Down syndrome, who developed hemolytic anemia after mitral valve repair. We observed that this condition is a rare complication in pediatrics, with only 7 cases reported in literature. Mechanical hemolysis should always be considered in the differential diagnosis of a new-onset hemolytic anemia, especially in patients with valvular heart disease, undergoing cardiac surgery.

A baby presented with a large right adrenal mass, multiple hepatic lesions and diffuse bone marrow infiltration when she was just over 1 month old. After needle biopsy and a histologic definition of neuroblastoma, she underwent chemotherapy and a subsequent complete resection. Three years after diagnosis, a large left adrenal localized mass was detected. The patient underwent complete surgical excision, and a diagnosis of poorly differentiated neuroblastoma with multiple lymph nodes involvement was defined. Adjuvant chemotherapy was initiated. To our knowledge, it is the first case report of metachronous bilateral adrenal neuroblastomas harboring completely different genetic expression profiles.

Primary soft-tissue lymphoma (PSTL) is a rare extranodal non-Hodgkin lymphoma, characterized by a mass growing within soft-tissue, which is connective tissue, adipose tissue, and skeletal muscle. Here, we describe a case of biphenotypic lymphoblastic lymphoma arising from soft tissue of the popliteal fossa in an 11-year-old boy. A pediatric review about PSTL revealed that anaplastic large cell lymphoma is the most common histological type and a biphenotypic lymphoblastic lymphoma has not yet been reported in childhood. Lymphoma should always be considered in patients presenting with a soft-tissue mass, and a comprehensive immunohistochemical evaluation, including B-cell, T-cell, and myeloid markers, is needed to make a correct diagnosis and establish the most suitable treatment.

Anaplastic large cell lymphoma (ALCL) is a histological subtype of non-Hodgkin lymphoma, largely characterized by anaplastic lymphoma kinase (ALK) positivity, resulting from the chromosomal translocation t(2;5). We report a pediatric case of ALK-positive ALCL with primary concomitant involvement of bone and central nervous system (CNS); thereafter, a literature review about pediatric primary bone and primary CNS ALCL was conducted. According to the analyzed data, our case is unique because it is characterized by the contemporary involvement of the spine and CNS. During and after chemotherapy, our patient was monitored by detecting minimal residual disease (MRD) through the analysis of fusion transcript nucleophosmin-ALK. MRD assessment, not only in bone marrow but also in peripheral blood, seems to be a very powerful tool for predicting the prognosis of pediatric ALCL patients, as already described in the literature. Moreover, as shown in our case, it could be used during the follow-up for early recognition of relapse.