Objective:To investigate the clinicopathological and molecular genetic characteristics of intracranial mesenchymal tumors with FET::CREB fusion transcript.Methods:The clinical and imaging data of 6 cases of intracranial mesenchymal tumors with FET::CREB fusion from December 2018 to December 2023 were collected at the First Affiliated Hospital of Zhengzhou University. Their histological features, immunophenotype and molecular characteristics were analyzed.Results:Among the 6 patients, 4 were males and 2 were females, and the median age was 20 years. The clinical symptoms were increased intracranial pressure in 5 cases and epilepsy in 1 case. The lesion sites were cerebellum (2 cases), frontal lobe (2 cases), parietal lobe (1 case), and cranioorbital communication (1 case). The radiological features mainly showed solid or cystic components, with obvious annular enhancement on MRI. The histopathological features showed a wide spectrum of morphology, clear boundaries and fibrous pseudocapsule. The tumor cells were arranged in a lamellar or nodular pattern, and some in cord or loose network. The tumor cells were spindle, oval, epithelioid or stellate. The stroma was collagenous or mucin-rich, and accompanied by abundant lymphocytes and plasma cells infiltration. By immunohistochemical staining, desmin, CD99 and EMA were expressed in 6 cases, CD68 in 1 case, MUC4 in 1 case, synaptophysin in 2 cases, and ALK in 1 case. The Ki-67 proliferation index was between 1%-15%. Molecular analysis showed EWSR1::ATF1 fusion in 3 cases, EWSR1::CREB1 fusion in 2 cases, and EWSR1::CREM fusion in 1 case.Conclusions:Intracranial mesenchymal tumors with FET::CREB fusion are relatively rare and typically occur in children and younger adults. These tumors have a broad morphological spectrum and often express desmin, CD99 and EMA. The molecular characteristics are the gene fusions of FET family (mainly EWSR1, FUS) with CREB family transcription factors (ATF1, CREB1 or CREM). It is necessary to distinguish these tumors from meningiomas and solitary fibrous tumors, and the combination of immunohistochemical staining and molecular genetic testing can effectively help identify these tumors.

Objective:To investigate the clinicopathological and molecular genetic characteristics of intracranial mesenchymal tumors with FET::CREB fusion transcript.Methods:The clinical and imaging data of 6 cases of intracranial mesenchymal tumors with FET::CREB fusion from December 2018 to December 2023 were collected at the First Affiliated Hospital of Zhengzhou University. Their histological features, immunophenotype and molecular characteristics were analyzed.Results:Among the 6 patients, 4 were males and 2 were females, and the median age was 20 years. The clinical symptoms were increased intracranial pressure in 5 cases and epilepsy in 1 case. The lesion sites were cerebellum (2 cases), frontal lobe (2 cases), parietal lobe (1 case), and cranioorbital communication (1 case). The radiological features mainly showed solid or cystic components, with obvious annular enhancement on MRI. The histopathological features showed a wide spectrum of morphology, clear boundaries and fibrous pseudocapsule. The tumor cells were arranged in a lamellar or nodular pattern, and some in cord or loose network. The tumor cells were spindle, oval, epithelioid or stellate. The stroma was collagenous or mucin-rich, and accompanied by abundant lymphocytes and plasma cells infiltration. By immunohistochemical staining, desmin, CD99 and EMA were expressed in 6 cases, CD68 in 1 case, MUC4 in 1 case, synaptophysin in 2 cases, and ALK in 1 case. The Ki-67 proliferation index was between 1%-15%. Molecular analysis showed EWSR1::ATF1 fusion in 3 cases, EWSR1::CREB1 fusion in 2 cases, and EWSR1::CREM fusion in 1 case.Conclusions:Intracranial mesenchymal tumors with FET::CREB fusion are relatively rare and typically occur in children and younger adults. These tumors have a broad morphological spectrum and often express desmin, CD99 and EMA. The molecular characteristics are the gene fusions of FET family (mainly EWSR1, FUS) with CREB family transcription factors (ATF1, CREB1 or CREM). It is necessary to distinguish these tumors from meningiomas and solitary fibrous tumors, and the combination of immunohistochemical staining and molecular genetic testing can effectively help identify these tumors.

Objective:To study the clinicopathological features and prognosis of nodal lymphoplasmacytic lymphoma/Waldenstrom′s macroglobulinemia (n-LPL/WM).Methods:A total of 19 cases of n-LPL/WM were collected from May 2009 to January 2020 at First Affiliated Hospital of Zhengzhou University. The clinicopathologic features, immunophenotype, Ig gene rearrangement (BIOMED-2), MYD88 L265P mutation status (by Sanger sequencing) and follow-up data (by telephone) were analyzed.Results:There were 15 males and 4 females with a median age of 61 years (range 43 to 82 years). There were 14 WM and five LPL. The most common symptoms were weakness, fatigue (9/19) and B symptoms (11/19). Majority of the patients (16/18) presented with systemic multiple lymphadenopathies. Eighteen patients presented at advanced stages (Ⅲ/Ⅳ stage). Serum M protein status was IgM (15 cases), IgG (1 case), IgA (1 case) and no-secretory type (2 cases). Seventeen patients had bone marrow involvement. Morphologically, all 19 cases were divided into two groups: typical group (9 cases) or atypical group (10 cases). In the typical group, the structures of the lymph nodes were preserved; the neoplastic cells were predominantly plasmacytoid lymphocytes or mixed small lymphocytes, plasmacytoid lymphocytes and plasma cells, without proliferation of FDC network and follicular implantation. In the atypical group, the tumor showed effaced nodal architecture (5 cases), mainly proliferation of small lymphocytes (6 cases), FDC proliferation and/or follicular implantation (6 cases), marginal zone B cell differentiation (4 cases) and diffuse amyloidosis (1 case). Hemosiderin deposition (19 cases), infiltration of fatty tissue (19 cases) and interstitial sclerosis (9 cases) were commonly seen in both groups. Immunohistochemically, the neoplastic B cells expressed CD20 and CD79α, and the neoplastic plasma cells were positive for CD38, CD138 and MUM-1; eight cases showed light chain restriction; of the seven detected cases, five expressed IgM and the other two expressed IgG and IgA respectively; four cases expressed CD23 weakly, Ki-67 index was 10%-30%. MYD88 L265P mutation was seen in 18/18 cases. There was no significant difference in clinicopathologic features and prognosis between the two groups ( P>0.05). The median follow-up time was 61 months, 11 patients were alive, while eight died; the 5-year survival rate was 21.1%. Conclusions:n-LPL/WM is rare, but patients usually present in advanced stages. It is easily confused with other small B-cell lymphomas with plasma cell differentiation, especially basing on morphologic features alone; thus the accurate diagnosis of n-LPL/WM requires a combination of clinical features, serum M protein, immunohistochemistry, bone marrow morphology,flow cytometry and MYD88 L265P mutation status etc. The prognosis of n-LPL/WM may be not very good, and further studies with more cases are needed.

Objective:To study the clinicopathologic and genetic features of Waldeyer′s ring peripheral T-cell lymphoma with follicular helper T cell immunophenotypes (wPTCL-TFH), with comparison to the nodal peripheral T-cell lymphoma with TFH immunophenotypes (nPTCL-TFH) and angioimmunoblastic T-cell lymphoma (AITL), as to know this rare tumor better.Methods:The clinical data, histopathology features, EBV positivity, T cell clonality and IDH2 R172 gene mutation in 8 cases of wPTCL-TFH were collected at the First Affiliated Hospital of Zhengzhou University from December 2015 to April 2019, and analyzed by immunohistochemistry, in situ hybridization, TCR gene rearrangement (BIOMED-2) and Sanger sequencing.Follow-up data were obtained by telephone. Results:There were 6 males and 2 females with a median age of 62.5 years (age ranging from 30 to 75 years). All patients had neither fever nor skin manifestations, but were all found mucosa thickened or mass of waldeyer′s ring with multiple lymph nodes enlarged by PET-CT/CT scans. Five of the 7 patients were at advanced stages (Ⅲ/Ⅳ stage). Microscopically, the mucosa was infiltrated diffusely and characteristically by numerous small-medium sized lymphocytes, lacking polymorphous inflammatory background and extra-follicular expansion of follicular dendritic cell networks (FDC networks). The clear T cells presented in 5 cases. Ulcers on mucosal surfaces (6 cases) and local-extensive loss of intramucosal glands (7 cases) were commonly noted. Granulomas composed of epithelioid histiocytes were observed in 2 cases. Immunohistochemically, all the tumor cells expressed CD4 and at least 2 types of follicular helper of T cell (TFH) markers: PD-1 (8/8), bcl-6 (8/8), CXCL13 (7/8) and CD10 (1/8). Most of the cases (6 cases) expressed CD30. EBV positive appeared in 4 cases. All 8 cases were T cell monoclonal. IDH2 R172 were wild-type in 6 cases. One patient died at the follow-up time on 18 months; the other 7 survived (the follow-up time varied from 3 to 10 months). Conclusions:wPTCL-TFH is rare, and its clinicopathological features are similar to nPTCL-TFH which may be the manifestation of the same disease at different stage, and partly overlapped with AITL. The differential diagnosis from PTCL-NOS is necessary and comprehensive analyses of clinical, morphological, immunohistochemical and genetic features can help make a correct diagnosis.

Objective: To investigate the clinicopathological characteristics, therapy and prognosis of patients with pulmonary mucoepidermoid carcinoma. Methods: The clinical data of 87 patients diagnosed as pulmonary mucoepidermoid carcinoma at The First Affiliated Hospital of Zhengzhou University from April 2011 to May 2016 were retrospectively analyzed. The clinicopathological features were summarized and the prognoses were analyzed. Results: Among the 87 patients with lung mucoepidermoid carcinoma, 53 were male and 34 were female, the gender ratio between men and women was 1.56∶1.The ages of patients were from 16 to 79 years and the median age was 52.5 years. Seventeen cases were diagnosed as stage Ⅰ, 28 cases were stage Ⅱ, 26 cases were stage Ⅲ, 16 cases were stage Ⅳ.Thirty-six patients were examined by immunohistochemistry, of which 29 cases were cytokeratin (CK) 5/6 positive, 29 cases were CK7 positive, 10 cases were CK positive, 28 cases were p63 positive, 14 cases were p40 positive, 17 cases were thyroid transcription factor-1 (TTF-1) positive, 11 cases were NapsinA positive, 2 cases were epithelial membrane antigen (EMA) positive, 4 cases were CK8/18 positive, 3 cases were surfactant proteins A (SPA) positive, 1 case was CAM5.2 positive and 1 case was CK14 positive. Among the 87 patients, 34 cases were treated by operation alone, 23 cases were treated by operation combined with chemotherapy, 5 cases were treated by radiotherapy combined with chemotherapy, 14 cases were treated by chemotherapy alone, 2 cases were treated by particle implantation combined with chemotherapy, 2 cases were treated by local radiofrequency hyperthermia combined with chemotherapy, and 7 cases without special treatment.Five patients with brain metastasis were treated with cerebral radiotherapy combined with sequential chemotherapy. The 1-year, 2-year and 5-year survival rates of 87 patients were 90.7%, 81.6% and 46.3%, respectively. The median survival time was 60 months. The prognoses of patients with lung mucoepidermoid carcinoma were related with the clinical stage, smoking and operative therapy (all P<0.05). Conclusions The age distribution of patients with pulmonary mucoepidermoid is a wide range, the incidence of male is higher than that of female. The diagnosis of pulmonary mucoepidermoid carcinoma mainly relies on the morphological diagnosis and the immunohistochemical detection is non-specific. The prognoses of patients with lung mucoepidermoid carcinoma are related with clinical stage, smoking and operative therapy. For patients who are inoperable and with single distant metastasis, local radiotherapy, other local treatment and chemotherapy can significantly improve their prognoses.

Objective: To explore the characteristics of clinical pathology, diagnosis, and prognosis of primary renal lymphoma (PRL).Methods: The clinical features, pathological features, immune phenotypes, treatment, and prognosis of 22 patients were retrospectively analyzed. Results: The PRL patients' ages ranged from 2 to 72 years (mean, 54.3 years), of which 13 patients were older than 50 years (59.1%). All of the 22 patients were diagnosed with non-Hodgkin's lymphoma (NHL), including 20 cases of B-cell lymphoma and 2 cases of T-cell lymphoma. Seven patients were still alive and survived for 6-50 months, but the other 15 were dead and survived for only 5-35 months. Conclusion: PRL is uncommon. Clinical manifestations and imaging performance specificity are not obvious. and easily misdiagnosed. Histopathology is still the golden standard for the final diagnosis of this entity. The kidney is most easily involved followed by the bladder. B-cell NHL is the common subtype, and the most common type is the diffuse large B-cell lymphoma. Up to now,no standard regime could be performed for PRL patients. At present, comprehensive therapy, including surgery and chemotherapy, is recommended. For patients with locally advanced or highly aggressive status, therapeutic effect with chemotherapy alone is usually satisfied.