Solitary fibrous tumor:A case report of this multifaceted tumor

BACKGROUND Solitary fibrous tumor(SFT)is a remarkably uncommon mesenchymal tumor.STAT6 level and a combination of clinical,pathological,and molecular features are required to arrive at a proper diagnosis.CASE SUMMARY In this report,we present an intriguing case involving a 43-year-old woman who initially exhibited symptoms of a bleeding retroperitoneal tumor,initially resembling a gastrointestinal stromal tumor,but later confirmed as an SFT.However,a year later,what was initially believed to be a recurrence of her SFT was instead identified as a desmoid tumor.CONCLUSION Distinguishing SFT from other tumors was pivotal.Correcting misdiagnoses of tumor type initially and of recurrence later was necessary for appropriate treatment of the correct desmoid type.

Application of ultrasound in aggressive angiomyxoma: Eight case reports and review of literature

Aggressive angiomyxoma （AAM） is a rare tumour that often occurs in soft tissues of the female genital tract. Eight cases of AAM are reported in this article, and the clinical features and ultrasound and magnetic resonance imaging （MRI） results of the eight cases are reviewed and summarized. The main complaints of all the patients were palpable and painless masses in the vulva or scrotum. The lesions were mainly located in the vulva, pelvis, and perineal region, with a large scope of involvement. The sonographic features of AAM were characteristic. On sonography, all of the masses were of irregular shape and showed hypoechogenicity, with a heterogeneous inner echotexture. Intratumoural and peritumoural blood fows were detected by colour Doppler imaging. On real-time ultrasonic imaging, prominent deformation of the lesions was observed bycompressing the masses with the probe. Some special imaging features were also revealed, including a la-minated or swirled appearance of inner echogenicity, and a fnger-like or tongue-like growth pattern. On MRI imaging, the lesions showed intermediate-intensity signals and intermediate to high-intensity signals on TI-weighted and T2-weighted sequences. A rapid and uneven enhancement pattern was demonstrated. After the comparison of sonographic features with MRIand pathological findings, we found the relevance of the ultrasonographic characteristics with MRI and his-tological features of AAM. Ultrasound can be a valuable imaging method for the preoperative diagnosis, eva-luation of scope, and follow-up of AAM.

Nodular fasciitis in the mesentery, a differential diagnosis of peritoneal carcinomatosis

Nodular fasciitis is a benign proliferative lesion composed of fibroblast-like cells that affects various sites in the body.We describe a patient with nodular fasciitis in the mesentery,encountered during laparotomy for the treatment of ascending colon cancer.The nodular fasciitis in our patient resembled peritoneal dissemination of malignancy on macroscopic observation.Because the treatment options change with concomitant peritoneal dissemination of gastrointestinal tract malignancy,recognition of this rare condition and preparation for unexpected nodular lesions are crucial.

Clinicopathologic features of pleomorphic hyalinizing angiectatic tumor of soft parts

Background Pleomorphic hyalinizing angiectatic tumor （PHAT） of soft parts is a rare soft tissue tumor, which is generally considered low-grade. To distinguish the tumor from other soft tissue lesions, we analyzed the clinicopathologic and ultrastructural features, immunophenotypes, and flow cytometric DNA ploidy of PHAT in 9 cases. Methods PHAT specimens were collected from 9 patients with PHAT from 1990 to 2004. Each specimen was cut into pieces and stained with hematoxylin-eosin, phosphotungstic acid-hematoxylin, Prussian blue, and Masson trichrome, respectively. Immunohistochemical stains for vimentin, S-100 protein, CD34, CD31, CD99, VEGF, desmin, CDl17, α-SMA, and MIB-1 were performed with the Envision system. Flow cytometry was used in four specimens, two of which were observed by electron microscopy. Results In the 9 cases, the PHAT occurred at the lower extremity in 2 patients, inguinal in 2, waist in 1, forearm in 1, buttock in 1, foot in 1, and the chest wall in 1. All the lesions presented in the superficial subcutaneous tissues. Follow-up data were available in 7 of the patients, among whom 2 （28.6%） had recurrence after primary therapy. Microscopically, typical PHAT was characterized by sheet-like proliferation of spindle or pleomorphic cells and clusters of thin-walled hyalinized cstatic vessels. In some areas of the tumor, hemosiderin-laden spindle cells, numerous small single vessels, and myxoid extracellular matrix could be identified, indicating an ＂atypical PHAT＂. Mitotic figures were rare in all the cases In 5 of the 9 patients （55.6%）, the tumor was typical PHAT; and in the other 4 （44.4%）, typical and atypical PHAT coexisted. Immunohistochemically, the neoplastic cells were positive for vimentin, CD34, CD99, and VEGF, but negative for S-100 protein, desmin, SMA, and CD31. In all the cases, the MIB-1 proliferative activity of the neoplastic cells was lower than 2%. Ultrastructural analysis did not reveal any evidence of specific differentiation. Aneuploidy was not detected by flow cytometry. Conclusions Histologically, typical PHAT is characterized by spindle and pleomorphic cells associated with an angiectatic vasculature. The neoplastic cells often express vimentin and CD34, and may be positive for CD99 and VEGF. Ultrastructurally, the tumor usually has no specific differentiation. The low MIB-1 index and the absence of aneuploidy in PHAT indicate a non-malignancy. However, we consider the tumor as a borderline neoplasm because of its aggressive behaviour, and suggest wide local resection with tumor-free margin for the treatment of the disease.