Classification of cysts with follicular germinative differentiation.

BACKGROUND: Cysts are very common in the routine of dermatopathology but follicular germinative (trichoblastic) differentiation in cysts is seen rarely. The presence of follicular germinative differentiation in a cyst alerts to consider the possibility of a basal cell carcinoma (BCC) arising in a cyst. METHODS: Five cystic lesions with zones of follicular germinative differentiation were collected. Hematoxylin and eosin sections were reassessed for architecture, types of follicular differentiation and stromal characteristics; immunohistochemical studies with Ber-EP4 were analyzed. Articles about follicular germinative differentiation in cystic lesions were reviewed. RESULTS: Cystic lesions with follicular germinative differentiation have been described in the literature under various names including trichoblastic infundibular cyst, cystic trichoblastoma, cystic panfolliculoma (CPF), dermoid cyst with basaloid proliferations, folliculosebaceous cystic hamartoma and BCC occurring in infundibular cysts. The lesions presented by us could be classified as three cystic trichoblastomas, one CPF and one cystic hamartoma with follicular germinative differentiation. CONCLUSIONS: Histopathologically, cystic trichoblastomas can be separated from CPFs. Some lesions defy classification and may be regarded as cystic follicular hamartomas. The presence of follicular papillae and bulb-like structures, advanced follicular differentiation like that of inner and outer root sheath exclude the differential diagnosis of BCC arising in a cyst.

Lymphoid polyps of the palatine tonsil.

Tonsillar lymphoid polyps are uncommon lesions that have rarely been studied. The authors describe the clinical, histopathologic, and immunohistochemical features of 6 tonsillar polyps in which lymphoid tissue represented more than 80% of the lesion. Presenting symptoms were tonsillar mass and/or dysphagia. No predisposing factor was detected. Microscopically, all polyps contained follicles with germinal centers, crypts lined by lymphoepithelium, and a small amount of fibrous tissue in the center of the lesion. B cells (CD20+), T cells (CD45RO+), plasma cells (kappa+ and lambda+) and vessels (lymphatic, D2-40+; blood, CD34+) presented distribution and architectural patterns as expected for lymphoid tissue of a palatine tonsil. Tonsillar lymphoid polyps are possibly hamartomas characterized by overgrowth of lymphoid elements, which maintain an architectural pattern and cellular composition similar to those of the palatine tonsil.

Medallion-like dermal dendrocyte hamartoma: a new clinically and histopathologically distinct lesion.

Dermal dendrocyte hamartomas are extremely rare; only two examples have been described with clinical features different from our cases and with incomplete immunohistochemical characterization. We report three female patients presenting a medallion-shaped, well-defined, slightly atrophic and asymptomatic congenital lesion. All 3 patients showed a fusiform-cell proliferation. Immunohistochemistry was positive for CD34, factor XIIIa, and fascin. Electron microscopy showed typical features of dermal dendrocytes. We believe that the lesions described represent a new, clinically and histopathologically distinct lesion originating in dermal dendrocytes. We propose to name it medallion-like dermal dendrocyte hamartoma.

Myoid hamartomas of the breast: report of 3 cases and review of the literature.

Hamartomas were first described by Albrecht in 1904, who defined them as tumor-like malformations in which there was abnormal blending of the normal components of an organ. The myoid hamartoma is a rare benign lesion of the breast and has an uncertain origin, possibly in the walls of the blood vessels, muscularis mammillae of the areolae, and mainly in myoepithelium. We report 3 cases of myoid hamartomas of the breast, with the clinical, radiologic, and histopathological findings, and review the literature. The 3 lesions showed normal breast ducts and lobules, entrapped by a muscular stroma and some foci of mature adipose tissue. The muscular origin of part of the stroma was confirmed by strong reactiveness with smooth-muscle actin.

Precocious puberty in children with tumours of the suprasellar and pineal areas: organic central precocious puberty.

UNLABELLED: During the past 11 y, 115 children younger than 8/9 y of age (female/male) with tumours of the suprasellar or pineal areas were followed in our clinic to study the incidence of precocious puberty. In addition, type of central lesion, clinical characteristics and gonadotropic secretion were studied in order to elucidate the different mechanisms of gonadal activation. A control group of 21 patients with idiopathic precocious puberty and a control group of 10 age-matched patients with suprasellar tumours without precocious puberty were also studied. Precocious puberty associated with organic central lesions was found at diagnosis in 30 patients (26%), in 9 out of 48 patients with glial cell tumours (18.7%), 6 out of 9 patients with germ cell tumours (66.6%), 11 out of 11 patients with hypothalamic hamartomas (100%) and in 4 out of 4 patients with subarachnoid cysts or arachnoidocele (100%). Precocious puberty was not found in any of 36 patients with craniopharyngioma. With the exception of one patient with pineal germinoma, all lesions were localized to the suprasellar area. In all patients with hypothalamic hamartoma, precocious puberty was diagnosed before 4 y of age, while in most patients with the other lesions, it was diagnosed after this age. Height SDS, weight increase and advancement of bone age were similar in both idiopathic and organic central precocious puberty. Maximal LH responses to GnRH in idiopathic and organic central precocious puberty were similar except for germ cell tumours. Patients with suprasellar tumours without precocious puberty had lower maximal LH (but not FSH) responses to GnRH, with the exception of germ cell tumours. In the latter, elevation of serum beta-hCG indicates that this gonadotropin was responsible for gonadal stimulation. In hypothalamic hamartomas, the prepubertal hiatus in the activity of the GnRH pulse generator was absent. The mechanism of this failure in the inactivation of GnRH is unknown. Data suggest that in glial cell tumours and in subarachnoid cysts, an unknown factor, probably secreted by the tumours, advances the tempo of GnRH maturation. Therefore, the aetiology of organic central precocious puberty is multiple and is directly related to location and type of lesion. CONCLUSION: This clinical information suggests that the onset of puberty is not the result of the disruption of a putative pulse generator inhibitory influence but the consequence of secretion of stimulatory substances by the lesions.

Hamartoma angiomatoso ecrino / Eccrine angiomatous hamartoma

Se presenta un paciente con hamartona angiomatoso ecrino, formación névica constituída por la asociación de alteraciones vasculares y sudoríparas ecrinas, de rara observación. No encontramos antecedentes bibliográficos argentinos, no llegando a 15 los casos de la bibliografía internacional. La clínica es de una placa o nódulos eritematosos o pigmentados, generalmente dolorosos, que a la fricción trasudan. Este detalle es diagnóstico. El tratamiento es quirúrgico o crioquirúrgico

Hamartoma angiomatoso ecrino / Eccrine angiomatous hamartoma

Se presenta un paciente con hamartona angiomatoso ecrino, formación névica constituída por la asociación de alteraciones vasculares y sudoríparas ecrinas, de rara observación. No encontramos antecedentes bibliográficos argentinos, no llegando a 15 los casos de la bibliografía internacional. La clínica es de una placa o nódulos eritematosos o pigmentados, generalmente dolorosos, que a la fricción trasudan. Este detalle es diagnóstico. El tratamiento es quirúrgico o crioquirúrgico