Infantile myofibromatosis: a series of 28 cases.

BACKGROUND: Infantile myofibromatosis (IM) is a rare disorder of fibroblastic/myofibroblastic proliferation in children. OBJECTIVES: We sought to document common and unusual characteristics of patients with IM. METHODS: This was a retrospective study of 28 children diagnosed with histopathologically confirmed IM between 1992 and 2012. Epidemiologic, clinical, and treatment data were reviewed. RESULTS: IM was more frequent in boys (60.8%). Skin lesions were congenital in 64.3% of cases. The solitary form accounted for 50% of cases. Most nodules were painless, arising in cutaneous or subcutaneous tissue. The multicentric form accounted for 39% of cases; the skin, subcutaneous tissue, or muscle was involved in 97.8% of cases, and the bones in 50% of cases. The generalized form had a mortality rate of 33% (one-third of cases). Multicentric and generalized forms regressed spontaneously; severe local complications were observed, and late recurrent nodules developed in a few cases. LIMITATIONS: The retrospective review and the ascertainment of patients (from the departments of obstetrics and pediatrics) may have introduced bias in the analysis of severity of the different forms of IM. CONCLUSION: The diagnosis of IM must be confirmed histopathologically because the clinical presentation can be misleading. The prognosis is usually good, although local morbidity can occur. The generalized and multicentric forms merit long-term follow-up.

Cutaneous B-cell lymphoblastic lymphoma in children: a rare diagnosis.

BACKGROUND: Lymphoblastic lymphoma (LBL) is a rare malignant neoplasm usually occurring in the mediastinum of children and adolescents. The B-cell immunophenotype of LBL (B-LBL) accounts for less than 20% of all cases and may involve extramediastinal areas, such as the skin. Although highly aggressive, LBL is potentially curable if diagnosed early. OBJECTIVE: We sought to describe the clinical and histopathologic features of B-LBL in children presenting with cutaneous lesions, and to highlight the specific features of this rare and serious disease. METHODS: Seven children with a confirmed diagnosis of cutaneous B-LBL were identified by retrospective chart review. The clinical and histopathologic features were documented, analyzed, and compared with cases previously published in the literature. RESULTS: Six children developed nodules on the head, and one child presented with lesions on the back and abdomen. Histopathology showed a diffuse dermal and subcutaneous monomorphous infiltrate made up of atypical cells with an immature B-cell phenotype. The average duration of the lesions before diagnosis was 3.2 months. A staging workup revealed extracutaneous disease in 5 patients, including bone-marrow involvement in 4 children. LIMITATIONS: This was a retrospective study with a small number of patients. CONCLUSION: The cutaneous lesions of B-LBL typically manifest as rapidly growing erythematous firm nodules located on the head. Awareness of these clinical features is important for the diagnosis to be reached rapidly and treatment started without delay.