[IgD expression in various immunoarchitectural patterns of nodular lymphocyte predominant Hodgkin lymphoma in children]. / Ekspressiya IgD pri razlichnykh immunoarkhitekturnykh patternakh nodulyarnoi limfomy Khodzhkina s limfotsitarnym preobladaniem u detei.

BACKGROUND: Nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) consist of lymphocyte predominant cell or LP-cell. Despite their origin from active germinal centers, in some cases LP-cells express IgD, which is characteristic of naive B-lymphocytes of the mantle zone. Due to the rarity of NLPHL, assessing the frequency of IgD-positive cases is difficult. This marker can serve not only for differential diagnosis with other diseases, but also indicate the possible heterogeneity of NLPHL, which is currently represented by six immunoarchitectural patterns. OBJECTIVE: To determine the frequency of IgD-positive cases of NLPHL in children with subsequent assessment of the association with types of immunoarchitectural patterns. MATERIAL AND METHODS: The study included 52 cases of NLPHL, which were divided to typical and atypical patterns. Differences between two groups were compared using Fisher's exact tests. RESULTS: IgD expression was found in LP-cells in 26 of 52 cases (50%) and was positively correlated with atypical types (typical - 5/23, 21.7% vs atypical - 21/29, 72.4%, p=0.0003), among which pattern C was most common. CONCLUSION: Due to the high incidence of IgD-positive cases in NLPHL, this marker may be useful in differential diagnosis with histologic mimics. At the same time, positive IgD status was associated with atypical patterns, which may likely determine the different biology of neoplastic cells within the same form.

[Melanotic neuroectodermal tumor of infancy. Clinical case of large fontanel tumor and literature review]. / Melanoticheskaya neiroektodermal'naya opukhol' mladentsev. Klinicheskii sluchai opukholi v oblasti bol'shogo rodnichka i obzor literatury.

Melanotic neuroectodermal tumor of infancy (MNTI) is a neonatal tumor with progressive growth and high recurrence rate. Aggressive growth and localization of tumor often lead to significant cosmetic defects of cranial and facial bones. The authors report MNTI in a 6-month-old boy with lesion of the large fontanel. Total resection was followed by recurrence after 3 weeks. Repeated resection with subsequent radiotherapy was performed. The follow-up period was 6 months after repeated resection. There was no tumor growth throughout this period. Considering this case and world experience, we can conclude that treatment strategy for MNTI is still unclear.