RESUMEN
CONTEXT.: Clinical, dermoscopic, and histologic diagnostic criteria may overlap in cases with scarring and nonscarring alopecia, making diagnosis difficult for clinicians and pathologists. New histopathologic discoveries indicate that the cutaneous adnexal structural and homeostatic unit made up of the pilosebaceous unit, eccrine sweat gland coils (ESGCs), and dermal white adipose tissue may have a role in hair follicle renewal. OBJECTIVE.: To verify the presence of adipose tissue in the dermis at the level of the isthmus, infiltrating the bundles of the arrector pili muscle in biopsies from the scalp of 3 scarring alopecias: frontal fibrosing alopecia (FFA), fibrosing alopecia in a pattern distribution (FAPD), and lichen planopilaris (LPP). DESIGN.: We performed a retrospective and descriptive survey of 71 female scalp biopsies from 2016 to 2022 diagnosed at the Dermatopathology Laboratory at Fluminense Federal University of Rio de Janeiro. Two pathologists reviewed and diagnosed the cases, correlating pathologic features with clinical and dermoscopic findings. RESULTS.: The histopathologic findings of adipose tissue infiltration in the dermis at the level of the isthmus and in the bundles of the arrector pili muscle and the displacement of ESGCs were more frequently identified in FFA, followed by FAPD and less frequently found in LPP. CONCLUSIONS.: According to our research, adipose tissue infiltration in the dermis at the level of the isthmus and in the bundles of the arrector pili muscle and the displacement of ESGCs were observed in 3 scarring alopecias (FFA, FAPD, and LPP) and seems to be involved in the development of scarring alopecia.
Asunto(s)
Tejido Adiposo , Alopecia , Cicatriz , Glándulas Ecrinas , Fibrosis , Liquen Plano , Humanos , Alopecia/patología , Femenino , Liquen Plano/patología , Liquen Plano/diagnóstico , Estudios Retrospectivos , Cicatriz/patología , Tejido Adiposo/patología , Glándulas Ecrinas/patología , Fibrosis/patología , Persona de Mediana Edad , Adulto , Cuero Cabelludo/patología , Folículo Piloso/patología , Anciano , BiopsiaRESUMEN
PURPOSE: Collision sellar lesions represent the coexistence of distinct histopathological lesions found in the sella turcica. They are uncommon entities and have mainly been reported as pituitary adenoma (PA) associated to Rathke cleft cyst (RCC). Pre- and perioperative diagnosis is difficult, since most of the cases appear clinically, radiologically, and macroscopically as solitary cystic sellar lesion. METHODS: A retrospective study of histological reports from patients operated for PA from 2013 to 2018 in a single neurosurgery reference center was performed. Patients who also exhibited RCC in the histological sections were included. Clinical and biochemical data were collected from medical files. MRI scans and histopathological slides were also reviewed. RESULTS: Among 554 PA, five patients (0.9%) presented the association of PA and RCC. At diagnosis, patients had median age of 60 years (33-78) with, at least, one pituitary dysfunction, and visual field loss and/or headache. There was a female predominance (n = 3). All patients had nonfunctioning PA. MRI studies showed a predominantly cystic lesion and were unable to distinguish both lesions. The definitive diagnosis was made by histopathology. CONCLUSION: The association of PA and RCC is extremely rare. On MRI, they appear as a solid-cystic or cystic sellar tumors. RCC can rupture causing granulomatous reaction with cholesterol crystal formation, which can be mistaken for craniopharyngiomas during surgery. Therefore, collision sellar lesion must be included in the differential diagnosis of cystic sellar lesions. The definitive diagnosis is made by histological study.