Evolution of epidermoid cyst into dermoid cyst: Embryological explanation and radiological-pathological correlation.

Intracranial dermoid and epidermoid cysts are usually considered to be two different entities in the radiological and surgical literature. Epidermoid cysts are classically off midline in location, isointense to cerebrospinal fluid on T1 and T2-weighted images and have restricted diffusion, whereas dermoid cysts are classically midline in location, have T1-hyperintense regions due to the presence of fat and show facilitated diffusion. We report a case of radiological epidermoid cyst in baseline imaging, which evolved into a radiological dermoid cyst over time, and explain this unique occurrence with a review of the embryology and histopathogenesis of these cysts.

Quistes epidermoides de cabeza y cuello / Epidermoid cysts of the head and neck

Los quistes epidermoides localizados en cabeza y cuello son poco comunes y pueden ser difíciles de diagnosticar. Se describen los casos de cuatro pacientes con quistes epidermoides de cabeza y cuello, dos con localización en la región sublingual y extensión suprahioidea, otro localizado en la pared orofaríngea posterolateral y otro en la región submaxilar y submentoniana. Fueron tratados con éxito mediante abordajes transorales y transcervical, respectivamente. Se realizó una revisión de la bibliografía y se describieron las características anatómicas, clínicas e histológicas y el tratamiento de estas infrecuentes lesiones. (AU)

Epidermoid cysts of the head and neck are rare and can be difficult to diagnose. Two cases of patients with epidermoid cysts of the floor of the mouth with suprahyoid extension, other located at posterolateral oropharynx wall andother located at the submandibular and submental space with extention to midline are described. They were successfully treated by a transoral and transcervical approach respectively. A review of the literature was performed, and the anatomical, clinical and histological aspects and treatment of these uncommon tumors were reported. (AU)

Congenital neck masses.

Congenital neck lesions reflect abnormal embryogenesis in head and neck development. A thorough knowledge of embryology and anatomy is critical in the diagnosis and treatment of these lesions. The appropriate diagnosis of these lesions is necessary to provide appropriate treatment and long-term follow up, because some of these lesions may undergo malignant transformation or be harbingers of malignant disease.

Immunohistochemical characterization of the epidermoid formation in the middle ear.

OBJECTIVE: To study the incidence, size, and origin of epidermoid formations after accurately characterizing them by cytokeratin immunohistochemical analysis. STUDY DESIGN: A strategy of screening sections for possible epidermoid formations in the entire eardrum area in paraffin-embedded, serially sectioned developing temporal bones was used. Unstained adjacent sections were subjected to immunohistochemical staining, to provide accurately identified epidermoid formations for a study of their appearance and size in relation to age. METHODS: The immunohistochemical expression patterns for epidermoid cytokeratins of several antibodies at different gestational ages were determined. Then, epithelial structures suspected as epidermoid formations were characterized as epidermoid with age-appropriate antibodies in 36 paraffin-embedded temporal bones from 19 cases with an age range of 6 gestational weeks to 15 months postpartum using a novel method of antigen retrieval by heating sections in a 70 degrees C water bath. RESULTS: Each of 22 temporal bones ranging in age from 16 weeks gestation to 8 months postpartum contained one or more, often numerous, epidermoid formations. Sizes of epidermoid formations increased significantly with increasing age. The formations were found anywhere in the annular lateral wall region of middle ear, but the majority were in the anterosuperior region. A further study of the interface between annular external canal epidermis and middle ear epithelium in a larger group suggested that epidermoid formations arise at approximately 16 gestational weeks from the external canal epidermis. CONCLUSION: The findings indicate that epidermoid tissue in the middle ear normally originates from external canal epidermis at approximately the 16th gestational week and grows before disappearing.

Acrosyndactyly with epidermoid inclusion cysts: evidence for the extrinsic theory.

A case of acrosyndactyly was treated with routine syndactyly release and full-thickness skin grafts. Two epidermoid inclusion cysts were found within the syndactylyzed index and middle fingers. This association is discussed along with the mechanism that best explains this unusual occurrence.

[Epidermoid cyst of the iris]. / Kyste épidermoïde de l'iris.

Epidermoid cyst of the iris is a primary cysts of the iris, and more precisely a congenital cyst of the iris stroma. The embryological origin of these tumours is controversial owing to the clinical and histological aspects. Because the possibility of complications, excision is often necessary and permits accurate histologic diagnosis.

Pilo-sebaceous cystic ectopy of the uterine cervix.

The infrequent finding of pilo-sebaceous cysts in an uterine cervix is presented. The different histopathogenetic hypothesis and Literature reports are critically reviewed. The histogenesis can be referred to ectodermic embryonal germs which come in the ectopic site following an abnormal cephalic migration. Also stressed is the possibility that neoplasms of the pilo-sebaceous structures could arise in the ectopic site and, thereafter, due to their rarity, might be under-diagnosed at the histology.

Epidermoid cysts of the liver.

To the four recorded cases of epidermoid cysts of the liver are added two cases recently seen in children. One was in a 4-yr-old girl and associated with biliary cirrhosis. The other was in a 5-mo-old boy. The former was treated by roux-en-y cystjejunostomy, the latter by enucleation. The origin of these cysts is unknown. One theory suggests derivation from accessory foregut buds. Because of their malignant potential, treatment should be by excision. Where this is impossible, roux-en-y cystjejunostomy offers satisfactory palliation.

Possible relationship between in utero diethylstilbestrol exposure and male fertility.

Seventeen men who were exposed in utero to diethylstilbestrol (DES), 12 non-DES-exposed volunteers, and 11 fertile control subjects were evaluated by physical examination, seminal fluid analysis, and sperm penetration assay (SPA). Fourteen of the 17 male subjects exposed to DES in utero and two of the 12 non-DES-exposed volunteers had SPAs of less than 14% and qualified as infertile by the criteria of this test. All 11 fertile control subjects had demonstrated SPA values in the fertile range. Thirteen of the 17 DES-exposed male subjects, four of the 12 non-DES-exposed volunteers, and four of the 11 fertile control subjects demonstrated at least one abnormality of the reproductive organs.

PIP: The association of in utero exposure to DES (diethylstilbestrol) and subsequent occurrence of clear cell carcinoma of the vagina and of lesion of the female reproductive tract is well known. Recent data have suggested that in utero DES exposure may also be harmful to male fetuses. This article presents the results of a study carried out on 17 male subjects exposed prenatally to DES, on 12 volunteers not exposed to DES, and on 11 husbands of pregnant women. All subjects were evaluated by physical examination, SFA (seminal fluid analysis), and SPA (sperm penetration assay). 14 out of 17 DES-exposed subjects and 2 out of 12 nonexposed volunteers has SPAs of less than 14%, which qualifies as infertile, while all 11 fertile control subjects had SPA values in the fertile range. 13 of the 17 DES-exposed subjects, 4 of the 12 nonexposed subjects, and 4 of the 11 control subjects had at least one abnormality of the reproductive organs, particularly varicocele and epididymal cysts. If one accepts SPA as a valid predictor of fertility than it seems possible that DES exposure may create a major fertility hazard for men.

Epithelial cysts of the neuraxis: presentation of three cases and a review of the origins and classification.

Benign, epithelial-lined cysts of the neuraxis may be asymptomatic or may behave as space-occupying lesions. Presentation of three such cysts, including an intramedullary epidermoid cyst, a lumbosacral subcutaneous enteric cyst that has an epithelium resembling ependyma, and a hypophyseal duct cyst, illustrates typical problems encountered. Review of their histogenesis and possible embryogenesis indicates that intracranial ependymal cysts and cysts of the sella turcica are not normally associated with other anomalies and frequently occur after middle age, whereas dermal and enteric cysts occur within the first two decades and are commonly associated with vertebral anomalies and other dysraphic syndromes. Enteric cysts may have a variable histologic appearance, including one resembling ependymal cysts. Recognition of the latter is important because of a possible associated dysraphic syndrome and the presence of an extraneuraxial component with the former but not the latter.