1/6. Incidental stromal-predominant mixed epithelial-stromal tumors of the kidney: a mimic of intraparenchymal renal leiomyoma.CONTEXT: Mixed epithelial-stromal tumor of the kidney is a recently recognized benign renal tumor that usually occurs in adult women and typically forms a sizable lesion with solid and cystic areas. The recognized morphologic spectrum of this recently described entity is evolving. OBJECTIVE: To review the clinicopathologic features of 3 small mixed epithelial-stromal tumors of the kidney that were incidental findings in kidneys removed for other reasons. DESIGN: The clinical presentation and morphologic findings of the 3 cases were reviewed. A panel of immunohistochemical stains was performed. SETTING: Academic medical center. RESULTS: All 3 lesions contained predominantly fascicles of smooth muscle mimicking leiomyoma, but they also had cellular subpopulations of smaller, mullerian-appearing stromal cells. Tubules present within the lesion were most abundant at the periphery, suggesting that they might be entrapped. Although only the spindled smooth muscle cells were immunoreactive for muscle markers desmin and actin, both the spindled smooth muscle cells and the cellular mullerian-appearing stromal cells demonstrated diffuse nuclear labeling for estrogen and progesterone receptors. CONCLUSIONS: Mixed epithelial-stromal tumor of the kidney may present as an incidental stromal-predominant lesion within the kidney. Such lesions are easily confused with leiomyomas or stromal-predominant angiomyolipomas.- - - - - - - - - - ranking = 1keywords = stromal (Clic here for more details about this article) |
2/6. Unusual morphologic features of endometrial stromal tumors: a report of 2 cases.endometrial stromal tumors with typical morphology usually do not pose diagnostic problems. However, the finding of unusual morphologic features may be misleading in the final interpretation of these tumors. Herein, we described two endometrial stromal sarcomas discovered in hysterectomy specimens of women 31 and 75 years of age. Features typical of endometrial stromal neoplasia were present in both cases. Additionally, in 1 case, extensive fatty metaplasia as well as smooth and skeletal muscle metaplasia were found; and in the second case, focal bizarre nuclei, smooth muscle differentiation, and fibrous change were present. The differential diagnosis in the first case included cellular intravenous leiomyomatosis/lipoleiomyomatosis with skeletal muscle differentiation; and in the second case, a cellular smooth muscle tumor with bizarre nuclei was considered.- - - - - - - - - - ranking = 158.99148920369keywords = endometrial stromal, stromal (Clic here for more details about this article) |
3/6. Dedifferentiated mixed stromal-smooth muscle tumor of the uterus. Report of a case.So-called dedifferentiation in mesenchymal neoplasms of the uterus is very rare. Among conventional low-grade stromal tumors only three cases of dedifferentiation were reported, whereas in mixed stromal-smooth muscle tumors the dedifferentiation was yet not described. Here we present such a case of low-grade mixed stromal-smooth muscle tumor with dedifferentiation. The tumor occurred in 52-years-old postmenopausal patient. The high-grade component representing a dedifferentiation showed morphology of undifferentiated sarcoma with myxoid change. The low-grade component with morphology of mixed stromal-smooth muscle tumor was limited to a few peripheral areas of the lesion. Immunohistochemically, the low-grade component showed typical positivity for CD10, estrogen receptor, progesterone receptor, and focal reactivity for myoid markers, whereas the dedifferentiated component expressed only vimentin, CD10 and estrogen receptor. This case demonstrates that low-grade mixed stromal-smooth muscle tumor of the uterus can dedifferentiate like a pure stromal tumor. It shows that extensive sampling/histological search may be needed for recognition of a minor component in a dedifferentiated tumor.- - - - - - - - - - ranking = 0.66666666666667keywords = stromal (Clic here for more details about this article) |
4/6. Single-stage resection of a mixed endometrial stromal sarcoma and smooth muscle tumor with intracardiac and pulmonary extension.A case of mixed endometrial stromal sarcoma and smooth muscle cell tumor of the uterus with intravenous extension into the right heart and pulmonary artery is presented. The current literature and diagnostic and therapeutic strategies of pelvic tumors with intravenous extension are reviewed.- - - - - - - - - - ranking = 132.43735211418keywords = endometrial stromal, stromal (Clic here for more details about this article) |
5/6. Gastrointestinal stromal tumor: evidence for a smooth-muscle origin.A gastrointestinal stromal tumor, arising from the rectal ampulla of a 63-yr-old man, was investigated using conventional techniques as well as Western blot analysis of its cytoskeleton proteins. The expression of desmin, muscle-specific actins, vimentin, S-100 protein, chromogranin, neuron-specific enolase, and keratins was studied using the avidin-biotin technique. The tumor cells showed a positive reaction only to antivimentin antibody. Ultrastructural analysis failed to provide conclusive evidence for neural or muscular origin of the tumor. Western blot analysis of the tumor whole-protein extract allowed identification of the presence of gamma-smooth-muscle actin, thus suggesting an enteric smooth-muscle origin of the tumor. This result seems partially to support a parenchymal smooth-muscle origin for S-100 protein and desmin-negative gastrointestinal tumors.- - - - - - - - - - ranking = 0.33333333333333keywords = stromal (Clic here for more details about this article) |
6/6. Multiple plexiform tumorlets of the uterus.Plexiform tumorlet is a rare lesion usually found in the myometrium and is believed to be a variant of epithelioid leiomyoma. Multiple plexiform tumorlets may have an infiltrative pattern and mimic endometrial stromal sarcoma. Only five cases of multiple plexiform tumorlets of the uterus have been reported, to the best of our knowledge. We now present the sixth case.- - - - - - - - - - ranking = 26.487470422837keywords = endometrial stromal, stromal (Clic here for more details about this article) |