Solitary fibrous tumor of the kidney: a case report

Abstract

We describe a case report of a rare cancer affecting the kidney of 63 years of age patient who underwent imaging studies from ultrasound, computed tomography, and magnetic resonance imaging, due to complaints: left back pain and urinary obstruction. Sonographic and radiological features of the mass found suggested the diagnosis of a malignant tumor of parenchymal origin. The pathological and immunohistochemical studies of the resected anatomical specimen, however, diagnosed a rare benign variant of solitary fibrous tumor originating in the inferior pole of the left kidney.

Complex treatment after pathohistological and immunohistochemical analysis in synchronous neoplasms - anorectal achromatic malignant melanoma and gastric extrapleural solitary fibrous tumor

“…In SFT with different organ localization, no histological and IНС difference is reported [54,[62][63][64][65]. CD34 antigen, which is a transmembrane glycoprotein, helps in the diagnosis of SFT [43,44], as it is highly positive in 90% -95% of patients [45,[47][48][49][50]52,[66][67][68][69][70][71][72][73][74][75][76]. In the presented clinical case, strong diffuse expression to CD34 was reported (Figures 5A and 5B).…”

“…Macroscopically, most of the SFT are encapsulated and rounded, sometimes lobulated with a homogeneous density. The tumor may be large, with a yellowish-brown cut surface, and in the presence of fatty differentiation (lipomatous variant), myxoid and hemorrhagic changes may be observed [48][49][50][51][52][53]. Tumor necrosis and capsular invasion are criteria for aggressive and malignant tumors (10% of cases) [48,51,52].…”

“…Some SFTs may contain in separate areas mature adipose tissue and/or multinucleated giant stromal cells, overlapping with the so-called lipomatous hemangiopericytomas and giant cell angiofibromas [47]. The malignant variant of SFT usually consists of hypercellular lesions showing at least focal-moderate cytological atypia, tumor necrosis, multiple mitoses/more than 4 mitoses of the field with an increase of 10 and capsular invasion [48,51,52]. Rare myxoid SFTs can create a problem with the differential diagnosis (DD) of much more aggressive neoplasms or soft tissue tumors with other differentiation.…”