ABSTRACT
Objective:To investigate the clinical and MRI features of the mixed epithelial and stromal tumor family (MESTF) of the kidney.Methods:From January 2009 to September 2021, 42 patients with pathologically-proven MESTF from the First Medical Center of Chinese PLA General Hospital were collected in this retrospective study. Clinical information, MRI features, and pathological results were documented. According to the Bosniak classification (BC) version 2019, all MESTFs were divided into cystic MESTFs (36 cases) and solid-cystic MESTFs (6 cases). The R.E.N.A.L. nephrometry score (RNS), lesion size, laterality, location, margin, shape, growth pattern, presence of protruding into renal sinus, hemorrhage, and enhancement pattern were evaluated and documented. Based on BC versions 2005 and 2019, all the cystic MESTFs were assessed and divided into low (Ⅰ, Ⅱ, ⅡF) and high (Ⅲ, Ⅳ) grades. The independent sample t test or Mann-Whitney U test were performed to compare age, RNS, and lesion size between cystic MESTFs and solid-cystic MESTFs. Pearson χ 2 test, continuity-adjusted χ 2 test or Fisher exact probability test were utilized to evaluated the differences of clinical and MRI features and the distribution of low or high grades in two versions of BC. Results:Forty-two MESTFs were unilateral and solitary masses, 25 males and 17 females, with a mean age of (41±13) years old. Compared to solid-cystic MESTFs, cystic MESTFs were prone to demonstrate endophytic growth pattern (χ 2=17.77, P<0.001), and no significant differences in other clinical and MRI features were observed between cystic and solid-cystic MESTFs (all P>0.05). There were 7 low-grade and 29 high-grade tumors in the BC version 2005, respectively. Meanwhile, 24 low-grade and 12 high-grade tumors in the BC version 2019, respectively. The distribution of low or high-grade tumors in the two versions of BC had a statistically significant difference (χ 2=16.37, P<0.001). Conclusion:MESTFs demonstrated middle-age onset and no gender predilection. Cystic MESTFs are more likely to exhibit endophytic growth pattern with low-grade classification in BC system version 2019.
ABSTRACT
Mixed epithelial and stromal tumor (MEST) represents a recently described biphasic kidney neoplasm, which predominantly affects perimenopausal females. The authors report the case of a young male patient with a MEST exhibiting positivity for estrogen and progesterone receptors. Computed tomography/magnetic resonance imaging (CT/MRI) showed an expansive lesion affecting the right kidney. Grossly, a solid-cystic tumor was identified, which measured 5.7 × 3.5 × 2.4 cm. On microscopic examination, a biphasic tumor constituted by stromal and epithelial elements, without significant atypias, was identified. The stromal element was composed of spindle cells revealing positive immunoexpression for actin, desmin, vimentin, and estrogen receptors. The epithelial component exhibited a predominantly tubular pattern showing positive immunoreaction for cytokeratins. The diagnosis of MEST was then established.
O tumor epitelial e estromal misto (TESM) representa uma neoplasia renal bifásica descrita recentemente que afeta predominantemente mulheres na perimenopausa. Os autores relatam o caso de um paciente jovem, do sexo masculino, com TESM exibindo positividade para receptores de estrogênio e progesterona. A tomografia computadorizada/ressonância magnética (TC/RM) mostrou lesão expansiva no rim direito. Ao exame macroscópico, identificou-se tumor sólido-cístico medindo 5,7 × 3,5 × 2,4 cm. À microscopia, foi encontrado tumor bifásico constituído por elementos estromais e epiteliais, sem atipias significativas. O componente estromal era composto por células fusiformes, exibindo imunoexpressão positiva para actina, desmina, vimentina e receptores de estrogênio. Os elementos epiteliais mostraram padrão predominantemente tubular e exibiram imunorreação positiva para citoqueratinas. O diagnóstico de TESM foi então estabelecido.
ABSTRACT
Purpose To investigate the clinicopathological features of adolescent mixed epithelial and stromal tumor of the kidney ( MESTK) and improve recognization of this rare disease. Methods Clinicopathological and immunohistochemical characteristics of MESTK occured in 17-year-old girl were studied. Reviewed the related literatures, clinical and pathological characteristics of adoles-cent MESTK were analysed comprehensively. Results Congenital perineal spill was the main clinical manifestations. Microscopically, the tumor showed nodules and was composed of a mixture of epithelial and stromal elements. Glands were lined with columnar or cilia-ted columnar cells. Stromal cells surrounding glands seemed like ovaries and away from glands seemed like the differentiation of smooth muscle. Immunohistochemical staining revealed that the epithelial cells were positive for CK7 and vimentin. Stromal cells expressed desmin, smooth muscle actin ( SMA) , ER and PR. It was noteworthy that stromal cells away from glands expressed desmin. Conclu-sions As a kind of rare benign neoplasm of kidney, MESTK often occurs in perimenopausal women. But MESTK can also occur in ad-olescence, and has nothing to do with the use of hormone. Therefore, the renal tumor occurred in teenagers with biphasic differentiation should be differentiated from MESTK.
ABSTRACT
Objective To investigate the pathological features and differential diagnosis of mixed epithelial and stromal tumor of the kidney(MESTK). Methods Three patients with MESTK were studied by light microscopy and immunohistochemistry,and related literatures were reviewed. Results In the three patients,two were females and one was male,with the mean age of 20 years old.Examined grossly,the tumors were well circumscribed and typically composed of multiple cysts and solid areas.Microscopically,the tumors were composed of epithelial and spindle cells,both of the which were well differentiated with no atypia and mitosis of the nuclei.The immunohistochemical staining showed positive for the cytokeratin in the epithelial cells,and Vimentin,SMA,actin,PgR or ER and WT-1 in the spindle cells.No tumor recurrence and metastasis was found in all the three patients by 25 to 29 months of follow up. ConclusionMESTK is an uncommon mixed renal neoplasm with a favorable prognosis.