J. Fuentes

Incidental lipoma-like hibernoma arising from the adrenal gland: A well-differentiated liposarcoma mimicker

Hibernomas are uncommon benign lipomatous tumors which show differentiation toward brown fat. To our knowledge, only one case of adrenal hibernoma has been previously reported. We describe a 55-year-old woman showing an incidental, 1.7 cm-hibernoma associated with a 2.6 cm-cortical adenoma producing primary hyperaldosteronism (Conns syndrome), both in the left adrenal gland. The hibernoma was composed predominantly of univacuolated mature fat cells admixed with small vessels. Scattered areas composed of large multivacuolated pale cells with central or paracentral nuclei, mimicking lipoblasts, accounting for less than 30% of the tumor, were found. These cells lacked nuclear hyperchromasia or marked atypia, were S100-positive, and showed numerous mitochondria reactive with the anti-mitochondrial antibody. A diagnosis of lipoma-like hibernoma was made. Pathologists should be aware of this variant of hibernoma to avoid misdiagnosis and excessive treatment.

Incidental bladder lipoma: a case report and review of the literature.

ABSTRACT Conventional lipoma is the most common benign mesenchymal neoplasm in adults. However, bladder lipoma is a rare tumor. We report an incidental 0.5-cm, mucosal, bladder lipoma in a 75-year-old man, successfully treated with endoscopic excision. The tumor was found during the extension study of a high-grade urothelial carcinoma of the renal pelvis. A review of the published cases, including the present report, yielded a total of 16. Conclusions on this review are presented. The case is being reported because its rarity and to highlight the importance of complete workup to clarify associated disorders that may suggest extension of a malignant process. ÖZ Lipom erişkinlerde en sık rastlanan benign mezenkimal neoplazidir. Ancak, mesanede nadiren izlenir. Burada, 75 yaşında erkek hastanın mesanesinde saptanan ve endoskopik eksizyon ile tedavi edilen 0,5 cm çapında bir lipom sunulmaktadır. Tümör, renal pelvis yerleşimli yüksek dereceli ürotelyal karsinom nedeni ile yapılan tarama sırasında saptanmıştır. Literatürde olgumuzla birlikte yayınlanmış olan olgu sayısı 16’dır. Olgumuz, nadir olduğu için ve ayrıntılı ve tam bir taramanın malignitelerden ayırımının yapılabilmesi için önemli olduğunu vurgulamak amacı ile sunulmaktadır.