Histopathologic and immunohistochemical features of sea urchin granulomas.

BACKGROUND: Paracentrotus lividus is the most common variety of sea urchin in the west coasts of Spain and has commercial value for the alimentary industry. Puncture with the spine of its rigid external skeleton may cause mechanical injury by skin penetration. It causes immediate local symptoms and, in some cases, a delayed reaction occurs in the site of injury, weeks to months later. In this case, persistent, firm, flesh-colored papules or nodules develop. MATERIAL AND METHODS: Twenty-four biopsies from 21 patients with the diagnosis of sea urchin granuloma were studied, as well the clinical data. Specimens were routinely processed and stained with hematoxylin-eosin and leucocyte common antigen, CD20, CD3, CD4, CD8, CD30, CD68, kappa and lambda. RESULTS: Patients presented with persistent, single or multiple, nodules or papules, usually located in the hands. They developed from 2 weeks to over 1 year after the injury. Histopathologically, granulomas were present in all but one case. Sarcoidal granulomas were more common than suppurative or necrobiotic granulomas. Immunohistochemistry showed a polymorphous lymphoid inflammatory infiltrate, with T leucocytes predominating in most cases. CONCLUSION: Histopathological examination of sea urchin granulomas shows a non-specific granulomatous inflammation, in most cases of sarcoidal type. Being aware of the triggering event is necessary for the correct diagnosis.

Clinicopathological and immnuohistochemical findings in a series of folliculosebaceous cystic hamartoma.

BACKGROUND: Folliculo-sebaceous cystic hamartoma (FSCH) is an uncommon skin condition presenting as a slow-growing papulo-nodular lesion, in or around the nose. Most cases are not clinically suspected and only histopathological examination allows the diagnosis. Pathological features include a dermal-located infundibulo-cystic structure with sebaceous glands radiating around, a stromal component encircling the epithelial structures, with clefts between the lesional epithelial and stromal parts, as well as between this and the adjacent dermis. RESULTS: We report eight patients with the diagnosis of FSCH (5 females and 3 males), with ages ranging from 35 to 77 years. Most cases (5 out of 8) were located in or around the nose and sizes were comprised between 0.6 and 1.2 cm. Lesions had grown for long periods of time, up to ten years in one case. Immunohistochemistry showed staining for p63 in the epithelial component of all lesions, while CD10 was only present in some sebocytes. CD34 and Factor XIIIa positive cells were present in the lesional stroma. Staining for androgen and alpha-estrogen receptors was also usually noticed. CONCLUSIONS: FCSH is a hamartomatous skin lesion, clinically indistinct but with well-defined histopathological features. Immunohistochemistry shows a profile very close to normal sebaceous glands.