Objective To explore the clinicopathological features ,diagnosis and differential diagnosis of pleuropulmonary blasto-ma(PPB) .Methods A case of PPB was reported by light microscopic observation ,immunohistochemistry and molecular pathology study with review of related literature .Results A 45-year-old female was admitted to the hospital because of cough and dyspnea . Chest radiogram revealed a solid mass in the left lung .Grossly ,the tumor was described as a firm lesion with lumina or multicystic components and well-circumscribed margins .Microscopically ,the tumor was composed of sheets of malignant primitive small cells and fascicles of embryonal rhabdomyosarcoma-like cells with foci hyalinized stroma .Beneath the benign epithelium ,the primitive mesenchymal cells showed as mixed blastematous and sarcomatous characteristics that plump spindle shaped cells presented poor differention with abundant eosinophilic cytoplasms and brisk mitotic activities .Immunohistochemically ,vimentin and MyoD-1 were positive in malignant small cells but some epithelial markers are negative .Meanwhile ,K-RAS extron 3 mutation was detected by high resolution melting analysis(HRMA) .Conclusion Pleuropulmonary blastoma(PPB) is a rare malignant tumor with unique clinicopathological features .It should be distinguished from some mimics such as pulmonary blastoma and embryonal rhabdomyo-sarcoma .

Background and purpose: Extraskeletal myxoid chondrosarcoma (EMC) is a malignancy of uncertain differentiation tumor characterized by a multinodular structure and abundant myxoid matrix. Its preferred sites were the deep soft tissues of the extremities. The aim of this study was to investigate the clinicopathologic characteristics, diagnosis and differential diagnosis of EMC. Methods: Seven cases of EMC were analyzed for clinicopathological and immunohistochemical features with review of the related literature. Results: It occurred predominantly in females (male/female=2︰5). Five cases were located in low extremities and two in upper limb girdles, more commonly near the joint. Grossly, the masses showed as grey, lobular and somewhat transparent with a relatively well-deifned margin. Microscopically, the small ovary or plump spindle-shaped cells arranged in strand and cord patterns and lobular architecture which separated by delicate fibrous networks with an abundant myxoid but hypovascular background. And the tumors were immunoreactive for vimentin, and partly for S-100 and EMA, meanwhile, negative for CK. Conclusion:EMC is a rare soft tissue sarcoma with distinctive histopathological features. It should be distinguished from some mimics especially those tumors with a myxoid stroma or chondroid differentiation, such as chordoma and chondrosarcoma.

Objective To investigate the clinicopathologic features, diagnosis and differential diagnosis of granulocytic sarcoma(GS)of the vulva. Methods One patient with GS of the vulva was analyzed on morphological characteristics,immunohistochemical stainings and clinical data with review of the literature. Results The patient was a 75-year-old lady. She was admitted to the hospital for a painless lump found in her left vulvar region. B-ultrasound revealed a solitary isoechoic mass at she left labia minora with an internal heterogeneous echo. Grossly, the tumor was described as a solid neoplasm with fish-fresh like cut surface and an ill-defined margin. Microscopically, the malignant cells grew in a diffuse sheet pattern and were small to medium in size,with scant cytoplasm.The nuclei were round or oval,and had finely dispersed chromatin. The mitotic rates were high.Immunohistochemically,the tumour cells expressed for myeloperoxidase(MPO),CD43, lysozyme and CD117. Conclusions GS of the vulva is extremely rare. In routine histopathology, it may be misdiagnosed as lymphoma, Ewing sarcoma and small cell carcinoma et al. Awareness of the morphology and precise diagnosis of GS of the vulva have significance for appropriate treatment and prognosis of the patients.

Objective: To investigate the clinicopathological characteristics, histogenesis, immunophenotypes, molecular genetic characteristics, diagnosis and differential diagnosis of calcifying fibrous tumors (CFT). Methods: A total of 32 cases of CFT (22 cases from Henan Provincial People′s Hospital and 10 cases from PLA Army Medical Center) diagnosed between June 2009 and February 2019 were reviewed. The clinical and pathologic data were analyzed. Results: There were 12 male and 20 female patients, aged from 15 to 63 years (mean 40.8 years). Eleven cases occurred in stomach, four cases in retroperitoneum, four cases in ovary, two cases in scrotum, two cases in mediastinum, two cases in head and neck, one case each in thoracic cavity, lung, adrenal gland, kidney, sigmoid colon, epididymis and mesosalpinx. All the tumors were solid masses with clear boundaries. The maximal dimension of the tumors ranged from 0.6 to 10.0 cm. Microscopically, there was hypocellular stromal sclerosis and wavy storiform coarse collagen with superimposed scattered or patchy lymphocytes and plasma cells; calcification or gravel formation were also detected. Immunohistochemistry showed that spindle cells were positive for vimentin and some were positive for CD34; and they were negative for calponin, SMA, desmin, S-100 protein, SOX10, STAT6, β-catenin, ALK, CD117, DOG1, CKpan, and EMA. No ALK rearrangement was detected by FISH in all cases. No C-KIT and PDGFRA mutation was detected in all the tested 11 cases of stomach, four cases of retroperitoneal and one case of sigmoid colon CFT. MDM2 was not amplified by FISH in all four tested cases of retroperitoneal CFT. Conclusions CFT is a rare benign tumor of fibroblastic cell origin. The diagnosis mainly depends on histomorphologic analysis and immunophenotyping. CFT should be differentiated from other benign and malignant spindle cell mesenchymal tumors.