A rare case of adipocytic tumor in subscapular region: hibernoma

Abstract

Hibernoma is a rare lipomatous tumor of brown fat origin that emerges from remnants of fetal brown adipose tissue. They are encapsulated, yellow-tan colored, painless and benign soft tissue tumors, usually seen in adults and occur with large cells that have acidophilic, granular and vacuolar cytoplasm and centraly nuclei. Our case is a 33-year-old female who had swelling in the subscapular region. Imaging studies depicted a lesion compatible with lipoma. Macroscopic evaluation of the excision specimen revealed brown, tan-yellow colored and hemorrhagic cut surface compatible with fat tissue. In microscopic examination, a tumor composed of cells with vacuolar, granular and eosinophilic cytoplasm, centrally or peripherally localized small, round nuclei, were observed. These cells were stained with immunhistochemical S-100 and were evaluated to be comparable with lipocytes. With these findings, the patient was diagnosed as having hibernoma. We present this case for its rarity, and for the fact that it can be treated with simple excision, and should be kept in mind especially in the differential diagnosis of lesions with high vascularity

 

Keywords

• Hibernoma,adipocytic tumor,subscapulary region

Subskapular bölgede nadir bir adipositik tümör vakası: hibernoma

Abstract

Hibernoma, fetal kahverengi adipoz dokusunun kalıntılarından kaynak alan, kahverengi yağ dokusu kökenli, nadir bir lipomatöz tümördür. Bu tümörler genellikle yetişkinlerde görülen, asidofilik, granüler ve vakuolar sitoplazmalı ve merkezi çekirdekli büyük hücrelerden oluşan, sarı-ten renkli, ağrısız ve iyi huylu yumuşak doku tümörleridir. Olgumuz, subsapular bölgede şişlik şikayeti olan 33 yaşında kadın hasta. Uygulanan Görüntüleme çalışmaları lipom ile uyumlu bir lezyona işaret etmiştir. Eksizyon örneğinin makroskopik değerlendirilmesinde tümör yer yer kahverenkli ve yer yer sarı-ten renkli ve kesit yüzü hemorajik yağ dokusu ile uyumlu görünümdeydi. Mikroskobik incelemede, santral veya periferik yerleşimli küçük yuvarlak nükleuslu; köpüksü, granüllü ve eozinofilik sitoplazmalı hücrelerden oluşan bir tümör gözlendi. Bu hücreler immünhistokimyasal olarak S-100 ile boyandı ve lipositlerle benzer olarak değerlendirildi. Bu bulgularla hastaya hibernom tanısı konuldu. Bu vakayı nadir görülmesi ve basit eksizyonla tedavi edilebilmesi ve özellikle yüksek vaskülariteli lezyonların ayırıcı tanısında akılda tutulması açısından sunmaya karar verdik.

Keywords

• Hibernoma,adipozit tümör,subskapular bölge

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