[Angiomatoid fibrous histiocytoma in children: 6 cases]. / Histiocytome fibreux angiomatoïde de l'enfant : 6 cas.

BACKGROUND: Angiomatoid fibrous histiocytoma (AFH) is a soft-tissue tumour of uncertain differentiation most often arising in the extremities of children and young adults. AFH is a little-known neoplasm and its rarity may result in it being misdiagnosed as either a reactive lesion or a benign or higher-grade tumour. We report 6 cases of AFH in children and we review the clinicopathological and molecular features of this neoplasm published in the literature. PATIENTS AND METHODS: The children (aged 4 to 16 years) presented a single nodule involving the forearm (4/6), the trunk or the buttock, and all 5 nodules appeared spontaneously. Microscopic examination revealed well-circumscribed nodular lesions comprising a fibrous pseudo-capsule, haemorrhagic non-endothelial-lined pseudocystic spaces, and sheets of spindle and ovoid cells with dense surrounding lymphoplasmacytic infiltrate. Tumours were positive for desmin, CD68, CD99 and smooth-muscle actin markers. A fusion gene (EWSR1-ATF1) was found in the 3 cases in which molecular investigation was performed. DISCUSSION: In our series, a diagnosis of AFH had in no event been evoked after clinical examination and radiological investigation. The diagnosis was based in all cases on recognition of characteristic features during histological examination and it was confirmed in 3 cases by the recognition of fusion genes. Complete excision with wide margins allowed complete cure in all cases, supporting a good prognosis of AFH, although long-term follow-up is still mandatory to rule out relapse or metastases, which although rare, are responsible for fatal cases. To avoid unnecessary surgery in patients with AFH, an ultrasound core-needle biopsy should be performed as a first step in order to provide precise diagnosis enabling complete excision to be performed, with the margins being decided in multidisciplinary meetings involving teams specialised in soft-tissue tumours.

[Clinical features of Spitz naevus in children: a retrospective study of 196 cases]. / Caractéristiques du nævus de Spitz chez l'enfant. Étude rétrospective de 196 cas.

AIMS: To better define the characteristics of Spitz naevus (SN) in children, to determine whether it was clinically diagnosed and to examine the differential diagnoses made according to age. In addition, to determine whether atypical spitzoid tumors (AST) have a different presentation from other forms of SN. PATIENTS AND METHODS: A two-centre retrospective survey was made of histopathological reports written over a 4-year period in children aged under 18 years. The inclusion criterion was unequivocal diagnosis of SN or AST. Age, gender, site, size, course, excision methods, presumptive clinical diagnoses and the percentage of correct diagnosis were analyzed for four distinct age groups. RESULTS: One hundred and ninety-six patients were included, 186 with SN and 10 with AST. Mean age at diagnosis of SN was 9 years. Female predominance and predilection for the lower limbs were seen for all age groups. Facial involvement was less frequent and chiefly affected children aged under 11 years. Most SN lesions measured between 4 and 8mm. They were often confused with either pyogenic granuloma or juvenile xanthogranuloma, mainly before the age of 11 years. An accurate diagnosis was made in 29% of cases, chiefly in the 0 to 5 year-old age group. No cases of AST were clinically recognized, but it was diagnosed occasionally on histological grounds for very small tumours and in very young children. CONCLUSION: Clinical diagnosis of SN is not always straightforward and in this study, AST exhibited no special features allowing it to be distinguished from SN. These results underline the need for caution in the event of SN in children, regardless of age or lesion size.