[Comparative histological analysis of different materials used for urethroplasty in children with proximal forms of hypospadias: preputial skin vs buccal mucosa].

AIM: Buccal mucosa and preputial skin grafts are used for staged urethroplasty in proximal forms of hypospadias in children. Aim of our study was to carry out a comparative histological analysis of preputial skin and buccal mucosa. METHOD: s and materials: Histological analysis of urethral tissue samples from 10 patients with proximal forms of hypospadias was conducted. All patients were treated with staged Brackas technique using free grafts at the Russian Childrens Clinical Hospital from 2013 to 2016. Patients were divided into two groups. In Group I (n=5), preputial skin graft was used for urethroplasty, while in Group II (n=5) buccal mucosa was taken. A histological study of both materials with comparison to a native urethra was performed. RESULTS: In Group I, the histological analysis showed keratinizing multilayered squamous epithelium, large number of dilated sweat and sebaceous glands with signs of inflammation, and hair follicles. In Group II, histological analysis revealed the presence of the typical structure for mucosal tissue, including multilayered flat non-keratinizing epithelium, as well as full absence of sweat, sebaceous glands, and hair follicles. CONCLUSION: comparative histological analysis of neourethra has shown the absence of sweat and sebaceous glands, hair follicles, and areas of chronic inflammation in buccal mucosa vs preputial skin, showing that buccal mucosa is more similar to native urethra. Therefore, buccal mucosa is favored as the material for urethroplasty.

[Osteochondroma in children and adolescents].

Osteochondroma is called a benign cartilage-forming tumor arising from an aberrant subperiosteal cartilage. Multiple osteochondromas syndrome (MOS) is an autosomal dominant disease, the basis for which is mutations in the EXT (EXT1 or EXT2) genes. Osteochondroma is one of the most common benign bone tumors. According to the WHO data, it is detectable in 35% of benign bone tumors and 8% of all surgically removed bone tumors. A total of 491 cases of bone tumors were analyzed in the children and adolescents diagnosed at the Department of Pathoanatomy, Russian Children's Clinical Hospital, Moscow, in 2009 to 2014. All the patients with osteochondroma were divided into 2 groups: 1) sporadic cases (n = 63) and 2) tumors included in MOS (n = 33). Both groups showed a preponderance of boys (39 boys and 24 girls in Group 1 and 21 boys and 12 girls in Group 2). Clinical, radiological, and morphological criteria for the diagnosis and differential diagnosis of osteochondromas in children and adolescents are given.