Objective: To investigate the clinicopathological characteristics of malignant gastrointestinal neuroectodermal tumors (GNET), and to describe their clinical, histological, immunophenotypic, ultrastructural, and molecular features, diagnosis and differential diagnosis. Methods: Three cases of malignant GNET were collected at Xijing Hospital of the Fourth Military Medical University, from 2013 to 2022. All patients underwent surgical resection of the tumor. Histological, immunohistochemical (IHC), ultrastructural and molecular genetic analyses were performed, and the patients were followed up for six months, three years and five years. Results: There were two males and one female patients. The tumors were located in the ileum, descending colon, and rectum, respectively. Grossly, the tumors were solid, firm, and poorly circumscribed, measured in size from 2 to 4 cm in greatest dimension, and had a greyish-white cut surface. These tumors were histologically characterized by a sheet-like or nested population of oval to spindled cells or epithelioid cells with weakly eosinophilic or clear cytoplasm, small nucleoli and scattered mitoses. Electron microscopy showed neuroendocrine differentiation, and no evidence of melanogenesis. IHC staining showed that the tumor cells were diffusely positive for S-100 protein, SOX10, CD56, synaptophysin and vimentin. They were negative for melanocytic markers, HMB45 and Melan A. All three cases showed split EWSR1 signals consistent with a chromosomal translocation involving EWSR1. Next-generation sequencing in one case confirmed the presence of EWSR1-ATF1 fusion. These patients were followed up for 6 months, 3 years and 5 years, respectively, and all of them developed possible lung or liver metastases, and one of them died of multiple pulmonary metastases. Conclusion: Malignant GNET has distinctive morphological, IHC, and molecular genetic features and it should be differentiated from other malignancies of the gastrointestinal tract, especially clear cell sarcoma and melanoma.
Male ; Humans ; Female ; Biomarkers, Tumor/analysis* ; Gastrointestinal Neoplasms/pathology* ; S100 Proteins/analysis* ; Melanoma

Objective: To investigate the clinicopathological characteristics, immunophenotype, molecular genetics and differential diagnoses of fibrocartilaginous lipomas which consist of adipose tissue, fibrocartilage and fibrous elements. Methods: The clinicopathological features, immunohistochemical profiles and molecular profiles in six cases of fibrocartilaginous lipomas diagnosed at Foshan Traditional Chinese Medicine Hospital, Fudan University Shanghai Cancer Center, the Fifth Affiliated Hospital of Zhengzhou University and the Fourth Affiliated Hospital of Harbin Medical University from January 2017 to February 2022 were included. The follow-up information, diagnosis and differential diagnoses were evaluated. Results: There were three males and three females with a median age of 53 years (range 36-69 years) at presentation. Tumors were located in the extremities, the head and neck region and trunk; and presented as painless masses that were located in the subcutaneous tissue or deep soft tissue. Grossly, three cases were well defined with thin capsule, one case was well circumscribed without capsule, two cases were surrounded by some skeletal muscle. The tumors were composed of fatty tissue with intermingled gray-white area. The tumors ranged from 1.50-5.50 cm (mean 2.92 cm). Microscopically, the hallmark of these lesions was the complex admixture of mature adipocytes, fibrocartilage and fibrous element in varying proportions; the fibrocartilage arranged in a nodular, sheet pattern with some adipocytes inside. Tumor cells had a bland appearance without mitotic activity. Immunohistochemical analysis using antibodies to SMA, desmin, S-100, SOX9, HMGA2, RB1, CD34, adipopholin was performed in six cases; the fibrocartilage was positive for S-100 and SOX9, adipocytes were positive for S-100, adipopholin and HMGA2; CD34 was expressed in the fibroblastic cells, while desmin and SMA were negative. Loss of nuclear RB1 expression was not observed. Other genetic abnormalities had not been found yet in four cases. Follow-up information was available in six cases; there was no recurrence in five, and one patient only underwent biopsy of the mass. Conclusions: Fibrocartilaginous lipoma is a benign lipomatous tumor with mature adipocytes, fibrocartilage and fibrous elements. By immunohistochemistry, they show the expression of fat and cartilage markers. No specific molecular genetics changes have been identified so far. Familiarity with its clinicopathological features helps the distinction from its morphologic mimics.
Male ; Female ; Humans ; Adult ; Middle Aged ; Aged ; Desmin/analysis* ; China ; Lipoma/pathology* ; Fibroblasts/pathology* ; S100 Proteins/analysis* ; Diagnosis, Differential ; Fibrocartilage/pathology* ; Biomarkers, Tumor/analysis*

OBJECTIVETo investigate the diagnostic role of STAT6 immunohistochemistry in solitary fibrous tumors (SFT)/meningeal hemangiopericytomas (HPC).

METHODEvaluated the expression of STAT6, vimentin, CD34, EMA, PR, S-100, CD56, GFAP and Ki-67 in a cohort of 37 SFT/meningeal HPC, 30 meningiomas and 30 schwannomas by immunohistochemistry staining.

RESULTSAll SFT/meningeal HPC demonstrated nuclear positivity for STAT6, and the proportion of positive tumor cells ranged from 60% to 95%, with no significant difference cases.Vimentin was strongly positive in all cases. CD34, EMA and PR positivity was found in 32 cases, 1 case and 4 cases, respectively.S-100 protein, CD56 and GFAP were negative; Ki-67 labeling index was 1%-8%. However, the meningiomas and schwannomas were negative for STAT6.

CONCLUSIONSSTAT6 is a relatively specific biomarker for SFT/meningeal HPC, and may be used in the diagnosis and differential diagnosis of SFT/meningeal HPC, especially for the atypical cases, and allows the precise pathologic diagnosis of SFT/meningeal HPC.

Antigens, CD ; analysis ; Antigens, CD34 ; analysis ; Antigens, Differentiation, T-Lymphocyte ; analysis ; Biomarkers, Tumor ; analysis ; Diagnosis, Differential ; Glial Fibrillary Acidic Protein ; analysis ; Hemangiopericytoma ; chemistry ; diagnosis ; Humans ; Immunohistochemistry ; Ki-67 Antigen ; analysis ; Meningeal Neoplasms ; chemistry ; diagnosis ; Meningioma ; chemistry ; diagnosis ; Neurilemmoma ; chemistry ; diagnosis ; S100 Proteins ; analysis ; STAT6 Transcription Factor ; analysis ; Solitary Fibrous Tumors ; chemistry ; diagnosis ; Vimentin ; analysis

Granular cell tumors (GCTs) are soft tissue tumors, which are thought to be derived from Schwann cells. Although most GCTs are reported to arise in tongue and oral cavity (30-50%), they can appear on any anatomic sites, even visceral organs. Herein, we report 5 cases of GCTs on unusual anatomic locations, such as palm, arm, thigh, finger, and vulvar area. Complete surgical excision is preferred treatment of choice to prevent recurrence. These cases emphasize that GCTs not involving oral cavity are more prevalent than expected, and the diagnosis should be histopathologically confirmed.
Adult ; Aged ; Biopsy ; Child ; Female ; Granular Cell Tumor/metabolism/*pathology/surgery ; Hand ; Humans ; Immunohistochemistry ; Middle Aged ; Mohs Surgery ; Neoplasm Recurrence, Local/*prevention & control ; S100 Proteins/analysis/metabolism ; Treatment Outcome

OBJECTIVETo explore the role of S100A4 in the epithelial-mesenchymal transition (EMT) in esophageal squamous cell carcinoma and its possible molecular mechanism.

METHODSThree chemically synthesized S100A4 siRNA sequences were transiently transfected into esophageal carcinoma EC9706 cells. EC9706 cells transfected with negative siRNA, lipofectamine 2000, and vacant EC9706 cells were used as control. Fluorescence quantitative RT-PCR and Western blot were used to detect the inhibition rate of S100A4 siRNA. S100A4 siRNA2 with the best inhibition rate was chosen to transiently transfect into EC9706 cells under the same conditions. The EC9706 cells transfected with negative siRNA, lipofectamine 2000 and vacant EC9706 cells were also used as control. Fluorescence quantitative RT-PCR and Western blot were used to detect the mRNA and protein expressions of E-cadherin, vimentin and snail. The morphology of EC9706 cells was observed under an inverted microscope. Boyden chamber and scratch test were used to detect the invasion and migration ability of EC9706 cells, and CCK8 assay was used to detect the proliferation ability of EC9706 cells. EC9706 cells transfected with S100A4 siRNA2 were further transfected with snail eukaryotic expression vector. The EC9706 cells transfected with S100A4 siRNA, EC9706 cells transfected with snail eukaryotic expression vector and vacant EC9706 cells were used as control. The above indexes of all the groups were observed, too.

RESULTSThe S100A4 mRNA and protein expression levels of the S100A4 siRNA2 group were 0.417 ± 0.041 and 0.337 ± 0.039, the transmembrane cell number was 61.608 ± 8.937, the scratch healing distance was (0.216 ± 0.064) mm, the A value was 0.623 ± 0.084, the E-cadherin mRNA and protein levels were 0.619 ± 0.032 and 0.495 ± 0.034, the vimentin mRNA and protein levels were 0.514 ± 0.032 and 0.427 ± 0.028, the snail mRNA and protein levels were 0.573 ± 0.029 and 0.429 ± 0.041. These data were significantly different with the liposome group, the negative control group and the blank group (P < 0.05 for all). After the S100A4 siRNA2 treatment for 24 h, the appearance of EC9706 cells changed to epithelial cell morphology. The transmembrane cell number and the scratch healing distance of the S100A4 siRNA2+snail eukaryotic expression vector group were (69.382 ± 9.666) cells and (0.274 ± 0.029) mm, the A value was 0.823 ± 0.101, the snail mRNA and protein levels were 0.704 ± 0.037 and 0.625 ± 0.031, the vimentin mRNA and protein levels were 0.712 ± 0.046 and 0.609 ± 0.038, and these data were significantly higher than those of the Sl00A4 siRNA2 group (P < 0.05 for all). The E-cadherin mRNA and protein levels of the S100A4 siRNA2+eukaryotic expression vector group were 0.437 ± 0.038 and 0.381 ± 0.031, significantly lower than those of the S100A4 siRNA2 group (P < 0.05 for all). However, snail had no effect on the morphology of EC9706 cells.

CONCLUSIONSS100A4 may be involved in the EMT process of esophageal squamous-cell carcinoma by regulating the expression of snail and then plays a role in the invasion and metastasis of esophageal carcinoma.

Cadherins ; analysis ; Carcinoma, Squamous Cell ; metabolism ; pathology ; physiopathology ; Cell Line, Tumor ; Epithelial Cells ; Epithelial-Mesenchymal Transition ; Esophageal Neoplasms ; metabolism ; pathology ; physiopathology ; Humans ; Indicators and Reagents ; Lipids ; RNA, Messenger ; analysis ; RNA, Small Interfering ; analysis ; physiology ; S100 Calcium-Binding Protein A4 ; S100 Proteins ; antagonists & inhibitors ; genetics ; physiology ; Snail Family Transcription Factors ; Transcription Factors ; analysis ; genetics ; Transfection ; Vimentin ; analysis ; genetics

OBJECTIVETo study the clinicopathologic features and differential diagnosis of adenoid cystic carcinoma in the esophagus.

METHODSTen cases of primary adenoid cystic carcinoma of the esophagus were retrieved from the archival file. The clinicopathologic and immunohistochemical features were studied. The differential diagnosis was analyzed.

RESULTSThe male-to-female ratio was 9: 1. The age of patients ranged from 59 to 76 years. There were 4 cases with tumor located in mid esophagus, 4 cases with tumor located in mid to lower esophagus and the remaining 2 cases in lower esophagus. Low-power histologic examination showed mainly expansive growth pattern, with cribriform, solid and focal tubular architectures identified. The tumor cells showed nuclear hyperchromasia. Both ductal and myoepithelial differentiation was demonstrated. The stroma showed myxoid degeneration in areas. Comedo-type necrosis was observed in 8 cases and moderate to severe squamous dysplasia was present in one case. Three cases showed focal areas of squamous cell carcinoma. Immunohistochemical study showed that the tumor cells were positive for p63 (10/10), CD117 (10/10) and S-100 protein (9/10). There was focal staining for calponin (2/10) and smooth muscle actin (2/10). The ductal structures expressed CK7 (10/10).

CONCLUSIONSAdenoid cystic carcinoma of the esophagus demonstrates unique morphologic features with expression of S-100 protein and consistent expression of CD117. The above characteristics help to distinguish this entity from basaloid squamous cell carcinoma, mucoepidermoid carcinoma and small cell carcinoma of the esophagus.

Aged ; Calcium-Binding Proteins ; analysis ; Carcinoma, Adenoid Cystic ; chemistry ; pathology ; Carcinoma, Small Cell ; chemistry ; pathology ; Carcinoma, Squamous Cell ; chemistry ; pathology ; Esophageal Neoplasms ; chemistry ; pathology ; Female ; Humans ; Immunohistochemistry ; Male ; Microfilament Proteins ; analysis ; Middle Aged ; S100 Proteins ; analysis

Spindle cell lipoma (SCL) is a benign lipomatous neoplasm typically located in the posterior neck and back of older males. It presents as a well-circumscribed mass in the buccal mucosa, tongue, floor of the mouth or hard palate. There are only two case reports of SCL in the gingiva and alveolar ridge. Here, we report a case of SCL in the mandibular mucogingival junction of a 68-year-old male. Clinical, histopathological and immunohistochemical findings are presented. Although oral SCL is rare, it should be considered in the differential diagnosis of spindle cell neoplasms occurring in the oral cavity.
Adipocytes ; pathology ; Aged ; Antigens, CD34 ; analysis ; Diagnosis, Differential ; Follow-Up Studies ; Gingival Neoplasms ; pathology ; Humans ; Lipoma ; pathology ; Male ; Mandible ; Proto-Oncogene Proteins c-bcl-2 ; analysis ; S100 Proteins ; analysis

OBJECTIVETo explore the clinicopathologic features, immunophenotype, differential diagnosis and gene mutation status of the Erdheim-Chester disease (ECD).

METHODSClinical and pathologic findings of 3 ECD cases were examined by gross, microscopic, immunohistochemical methods and BRAF V600E mutation. Related literatures were reviewed.

RESULTSTwo male patients and one female patient presented clinically with multiple skin nodules, bone pain and bony lesions by imaging study. Microscopically, the lesions were composed of spindle-shaped fibroblasts, foamy histiocytes and scattered Touton-type giant cells embedded in reactive fibrous tissue. Lymphocytes, plasma cells, and multinucleated giant cells were also found. Immunohistochemically, all histiocytes were positive for CD68, none of which expressed CD1a, although 2 cases focally expressed weak S-100 stain. In 2 cases,BRAF V600E mutation was detected.

CONCLUSIONSECD is a rare disease of xanthogranulomatous histiocytosis.Its diagnosis relies on pathological and immunohistochemical findings, but correlation with clinical information, especially radiographic findings should be performed.No effective treatment of the disease is currently available.

Antigens, CD ; analysis ; Antigens, CD1 ; analysis ; Antigens, Differentiation, Myelomonocytic ; analysis ; Diagnosis, Differential ; Erdheim-Chester Disease ; genetics ; immunology ; pathology ; Female ; Humans ; Male ; Mutation ; S100 Proteins ; analysis ; Treatment Outcome

Several pathologic characteristics are associated with an adverse clinical outcome in papillary thyroid carcinoma (PTC), including the histological variant. This study aimed to investigate immunohistochemical expression and BRAF mutation status based on the histological variant and evaluated potential markers of aggressive behavior of PTC in Korean patients. In all, 407 PTC cases were classified to each histological variant, and the 94 representative cases were subjected to immunohistochemistry and BRAF mutation analysis. The classic type, follicular variant (FV) and tall cell variant (TCV) represented 76.9%, 14.2% and 6%, respectively. TCV showed a larger tumor size (P = 0.009), frequent extrathyroidal extension (P = 0.022) and cervical lymph node (LN) metastasis (P = 0.018). TCV and FV showed the reduced expression of galectin-3 (P = 0.003) and HBME1 (P = 0.114). Regardless of histology, PTEN loss and diffuse S100A4 expression were associated with LN metastasis (P = 0.007, P = 0.013). All TCVs harbored BRAF V600E mutation, and FV harbored less BRAF V600E mutation (P = 0.043). Immunohistochemical evaluation showed characteristic patterns in histological variants. PTEN and S100A4 expression are suggested as indicators of regional lymph node metastasis.
Adult ; Aged ; Aged, 80 and over ; Asian Continental Ancestry Group/*genetics ; Carcinoma, Papillary/genetics/metabolism/*pathology ; DNA Mutational Analysis ; Exons ; Female ; Galectin 3/metabolism ; Humans ; Immunohistochemistry ; Lymphatic Metastasis ; Male ; Middle Aged ; Mutation ; PTEN Phosphohydrolase/metabolism ; Proto-Oncogene Proteins B-raf/*genetics/metabolism ; Republic of Korea ; S100 Proteins/metabolism ; Thyroid Neoplasms/genetics/metabolism/*pathology ; Tumor Markers, Biological/metabolism ; Young Adult

OBJECTIVETo detect the expression of S100A6 in gastric cancer, and to investigate the regulation mechanism of S100A6 in invasion and metastasis of gastric cancer.

METHODSExpression of S100A6 protein in gastric cancer specimens, tissue adjacent to cancer, liver and lymph node metastasis tissue specimens was detected by immunohistochemical staining in 166 patients with gastric cancer from January 1995 to December 2001. Their association with clinicopathological factors was analyzed. Chromatin Immunoprecipitation-chip was used to detect the downstream factors potentially regulated by S100A6 in gastric cancer cell lines KATO3. S100A6 gene was transfected into gastric cancer cell line AGS, and cell invasion experiment and real time Q-polymerase chain reaction(RT Q-PCR) were used to detect the cell invasive ability and the mRNA expression of invasion-related factors (CDK5 and FLJ12438) in transfection group, negative control group and blank control group, respectively.

RESULTSLow expression of S100A6 protein was found in cytoplasm of peritumoral tissues. In gastric cancer, liver and lymph node metastasis tissues, S100A6 protein expression was up-regulated in cytoplasm and (or) nuclei, especially in the tumor cells of invasive edge. The expression rates of gastric cancer, liver and lymph node metastasis tissues were 67.5%(112/166), 92.9%(26/28) and 100% (30/30) respectively. The high expression of S100A6 was associated with tumor local invasion, lymph node metastasis, cancer embolus, distant metastasis and TNM stages(all P<0.05). The transmembrane cell number was 31.3±5.5 in the S100A6 transfection group, significantly higher than that in negative control group (7.7±1.5) and blank control group (9.3±2.1)(both P<0.05), indicating an increase of cell invasion after S100A6 transfection. In transfection group, CDK5 mRNA expression was significantly higher than that in negative control group and blank control group(P<0.05). While FLJ1243 mRNA expression was similar among the three groups(P<0.05).

CONCLUSIONS100A6 may affect the malignant biological behavior of gastric cancer cells by regulating the expressions of down-stream invasion-associated factors, such as CDK5.

Cell Cycle Proteins ; metabolism ; Humans ; Lymphatic Metastasis ; Neoplasm Invasiveness ; Neoplasm Staging ; Oligonucleotide Array Sequence Analysis ; Real-Time Polymerase Chain Reaction ; Reverse Transcriptase Polymerase Chain Reaction ; S100 Calcium Binding Protein A6 ; S100 Proteins ; metabolism ; Stomach Neoplasms ; metabolism ; pathology ; Transfection ; Up-Regulation