[Clinical features and prognostic analysis of colorectal extranodal NK/T cell lymphoma].

Objective: To investigate the clinical manifestations, endoscopic characteristics, and prognostic factors of patients with colorectal extranodal NK/T cell lymphoma. Methods: The clinical data of 52 patients with colorectal extranodal NK/T cell lymphoma admitted to the First Affiliated Hospital of Zhengzhou University from January 2013 to January 2023 were retrospectively analyzed. Their clinical manifestations and endoscopic characteristics were summarized, and the prognostic factors were analyzed by Cox regression model. Results: Among the 52 patients with colorectal extranodal NK/T cell lymphoma, there were 35 males and 17 females, with a male-to-female ratio of 2.06∶1. Among the general symptoms, abdominal pain was the most common (39 cases), and B symptoms occurred in 47 patients, among which fever was the most common lymphoma B symptom (42 cases), and gastrointestinal perforation was the most common complication (18 cases). Forty-three patients underwent colonoscopy, and the main manifestations under endoscopy were the ulceration type (24 cases). The ulcers were irregular at the edges and often covered with moss at the bottom. The median survival time was 4.3 months. Multivariate Cox regression analysis showed that hemocytic syndrome (HR=8.50,95% CI: 1.679-8.328,P=0.001), serum albumin (HR=3.59,95% CI: 1.017-6.551, P=0.048), and with or without chemotherapy (HR=0.31, 95% CI: 0.246-1.061, P=0.025) were independent factors influencing the overall survival of patients with colorectal extranodal NK/T cell lymphoma. Conclusions: Colorectal extranodal NK/T cell lymphoma is a rare disease with a very poor prognosis. When patients present with abdominal pain and lymphoma B symptoms, and when ulcers with irregular edges and moss covering the bottom are found under endoscopy, the disease should be considered, and endoscopic biopsy should be taken in time for pathological diagnosis. The prognosis of patients with hemophagocytic syndrome and hypoproteinemia is poor. This disease should be treated with chemotherapy and surgery, and on this basis, hemophagocytic syndrome and hypoproteinemia should be treated to improve the prognosis of patients.

[Follicular lymphoma with a predominantly diffuse growth pattern with 1p36 deletion: a clinicopathologic analysis of eight cases].

Objective: To investigate the clinical and pathologic features and diagnosis of follicular lymphoma (FL) with a predominantly diffuse growth pattern (DFL) with 1p36 deletion. Methods: Eight cases of DFL with 1p36 deletion diagnosed at Department of Pathology, Beijing Friendship Hospital, Capital Medical University (n=5) and the Affiliated Cancer Hospital of Zhengzhou University, Henan Cancer Hospital (n=3) from January 2017 to January 2023 were included. Their clinicopathologic features and follow-up data were analyzed. Immunohistochemistry and fluorescence in situ hybridization (FISH) were performed. Results: There were five males and three females, with a median age of 67 years, and inguinal lymphadenopathy was found as the main symptom. Histologically, similar morphologic features were sheared among all cases, with effaced nodal structure and characterized by proliferation of centrocytes in a diffuse pattern, with or without follicular components. The germinal center-related markers such as CD10 and/or bcl-6 were expressed in the tumor cells, and 1p36 deletion but not bcl-2 translocation was appreciable in these cases. Conclusions: DFL with 1p36 deletion is a rare subtype of FL, with some overlaps with other types of FL or indolent B-cell lymphomas in their pathologic features. An accurate diagnosis requires comprehensive considerations based on their clinical, pathologic, immunohistochemical, and molecular features.

[Clinicopathological features of primary mucosal CD30-positive T-cell lymphoproliferative disorders].

Objective: To investigate the clinicopathological features and differential diagnosis of primary mucosal CD30-positive T-cell lymphoproliferative disorders (pmCD30+TLPD). Methods: Eight cases of pmCD30+TLPD diagnosed from 2013 to 2023 at the Department of Pathology, Beijing Friendship Hospital Affiliated to Capital Medical University and Beijing Ludaopei Hospital were retrospectively collected. The immunophenotype, EBV infection status and T-cell receptor (TCR) clonability of tumor cells were examined. The clinicopathological features were analyzed and related literatures were reviewed. Results: There were 5 females and 3 males, aged 28 to 73 years, without B symptoms, lack of trauma and autoimmune diseases. Seven cases occurred in oral mucosa and one in anal canal mucosa. Submucosal nodules with ulcerations were presented in all cases except one, which only submucosal nodule. Morphologically, there was different distribution of allotypic lymphocytes in inflammatory background. Four cases showed "kidney-shaped", "embryonic" and "horseshoe-shaped" cells, and one case resembled Hodgkin and Reed/Sternberg (HRS) cells. Allotypic lymphocytes expressed CD3 (7/8), CD4+/CD8-(7/8) and CD4-/CD8-(1/8). CD30 was uniformly strongly positive while ALK and CD56 were negative. In situ hybridization of EBER was negative in five cases (5/5). Clonal TCR gene rearrangement was positive in two cases. Four patients did not receive radiotherapy or chemotherapy. All the seven patients survived without disease except one died due to concurrent leukopenia. Conclusions: pmCD30+TLPD had a broad morphological spectrum and could be easily confused with primary cutaneous CD30+TLPD and systemic ALK-negative anaplastic large cell lymphoma involving mucosa, which may lead to misdiagnosis. Although the majority of the cases had a favorable prognosis, a few cases relapsed or progressed to lymphoma.

[Clinicopathological and molecular genetic features of confined placental mosaicism].

Objective: To investigate the clinicopathological and genetic features of confined placental mosaicism (CPM) and its effect on fetal intrauterine growth. Methods: Fourteen CPM cases of Haidian Maternal and Children Health Hospital were collected from May 2018 to March 2022. Clinicopathological examination on placental specimens and molecular genetic analysis were performed. Results: The age of the parturient women ranged from 27 to 34 years, with an average age of (30.0±3.54) years. The gestational weeks ranged from 35+1 to 41+2 weeks. There were 4 premature births and 10 term births, among which 6 were female and 8 were male fetuses. Nine cases (9/14) had adverse pregnancy outcomes, including 7 cases of fetal growth restriction. The weight of CPM placenta decreased, with 6 cases below the 10th percentile of weight standards and 5 cases between the 10th and 25th percentile. All 14 CPM placental specimens showed morphological changes of perfusion dysfunction to varying degrees, with mainly placental-maternal vascular malperfusion followed by placental-fetal vascular malperfusion. The mosaic chromosomes in different CPM cases varied, with 16-trisomy/monosomy mosaicism being the most common followed by 7-trisomy and 21-trisomy/monosomy mosaicism. The mosaic proportion was unequal in different parts of the same CPM placenta, with the mosaic proportion of umbilical cord, fetal membranes, fetal surface, maternal surface, and edge ranging from 1% to 70%. Conclusions: The mosaic chromosomes in different CPM cases vary, and the mosaic proportion is unequal in different parts of the same CPM placenta. The pathological morphology is mainly manifested as perfusion dysfunction, which can lead to adverse pregnancy outcomes such as fetal growth restriction and preterm birth.

[Progressively transformed germinal center-like follicular T-cell lymphoma:a clinicopathological analysis of 14 cases].

Objective: To investigate the clinicopathologic features of progressively transformed germinal center-like follicular T-cell lymphoma (PTGC-like FTCL). Methods: The clinicopathologic data of 14 PTGC-like FTCL cases that were diagnosed at the Beijing Friendship Hospital Affiliated to the Capital Medical University from January 2017 to January 2022 were retrospectively collected. Clinicopathological features, immunophenotype, and Epstein-Barr virus (EBV) infection status were analyzed in these cases. Polymerase chain reaction (PCR) was performed to detect the clonal gene rearrangements of T cell receptor (TCR) and the immunoglobulin (Ig) in 10 and 8 cases, respectively. Results: The male to female ratio was 5∶2. The median age was 61 years (range 32-70 years). All patients had lymphadenopathy at the time of diagnosis. By using the Ann Arbor system staging, seven cases were classified as stage Ⅰ-Ⅱ, and seven cases as stage Ⅲ-Ⅳ. Seven cases had B symptoms, four cases had splenomegaly, and two cases had skin rash and pruritus. Previously, three cases were diagnosed as classic Hodgkin's lymphoma, three cases as small B-cell lymphoma, two cases as atypical lymphoid hyperplasia unable to exclude angioimmunoblastic T-cell lymphoma (AITL), one case as EBV-associated lymphoproliferative disorder, and one case as peripheral T-cell lymphoma (PTCL) associated with the proliferation of B cells. All the 14 cases showed that the large nodules were composed of mature CD20+, IgD+B lymphocytes admixed with small aggregates of neoplastic cells with pale to clear cytoplasm. Moreover, hyperplastic germinal centers (GCs) and Hodgkin/Reed-Sternberg-like (HRS-like) cells were seen within these nodules in two and five cases, respectively. The neoplastic cells expressed CD3 (14/14), CD4 (14/14), PD1 (14/14), ICOS (14/14), CD10 (9/14), bcl-6 (12/14), CXCL13 (10/14), and CD30 (10/14). The HRS-like cells in five cases expressed CD20 (2/5), PAX5 (5/5), CD30 (5/5), CD15 (2/5), LCA (0/5), OCT2 (5/5) and BOB1 (2/5). Moreover, neoplastic T cells formed rosettes around HRS-like cells. EBV-encoded RNA (EBER) in situ hybridization showed scattered, small, positive bystander B lymphocytes in 8/14 cases, including 3/5 cases containing HRS-like cells. All tested cases (including five with HRS-like cells) showed monoclonal TCR gene rearrangement and polyclonal Ig gene rearrangement. Conclusions: PTGC-like FTCL is a rare tumor originated from T-follicular helper cells. It could be distinguished from angioimmunoblastic T-cell lymphoma by the formation of follicular structure, and lack of follicular dendritic cell proliferation outside the follicles and the polymorphous inflammatory background. In addition, it should be differentiated from lymphocyte-rich classical Hodgkin's lymphoma and low-grade B cell lymphoma.

[Clinicopathological features of fibrin-associated diffuse large B-cell lymphoma: a report of six cases].

Objective: To investigate the clinical, pathological and immunophenotypic features, molecular biology and prognosis of fibrin-associated large B-cell lymphoma (LBCL-FA) in various sites. Methods: Six cases of LBCL-FA diagnosed from April 2016 to November 2021 at the Beijing Friendship Hospital, Capital Medical University, Beijing, China and the First Affiliated Hospital, Wenzhou Medical University, Wenzhou, China were collected. The cases were divided into atrial myxoma and cyst-related groups. Clinical characteristics, pathological morphology, immunophenotype, Epstein Barr virus infection status, B-cell gene rearrangement and fluorescence in situ hybridization of MYC, bcl-2, bcl-6 were summarized. Results: The patients' mean age was 60 years. All of them were male. Three cases occurred in atrial myxoma background, while the others were in cyst-related background, including adrenal gland, abdominal cavity and subdura. All cases showed tumor cells located in pink fibrin clot. However, three cyst-related cases showed the cyst wall with obviously fibrosis and inflammatory cells. All cases tested were non germinal center B cell origin, positive for PD-L1, EBER and EBNA2, and were negative for MYC, bcl-2 and bcl-6 rearrangements, except one case with MYC, bcl-2 and bcl-6 amplification. All of the 5 cases showed monoclonal rearrangement of the Ig gene using PCR based analysis. The patients had detailed follow-ups of 9-120 months, were treated surgically without radiotherapy or chemotherapy, and had long-term disease-free survivals. Conclusions: LBCL-FA is a group of rare diseases occurring in various sites, with predilection in the context of atrial myxoma and cyst-related lesions. Cyst-related lesions with obvious chronic inflammatory background show more scarcity of lymphoid cells and obvious degeneration, which are easy to be missed or misdiagnosed. LBCL-FA overall has a good prognosis with the potential for cure by surgery alone and postoperative chemotherapy may not be necessary.

[Clinicopathological features and prognosis of cytotoxic T-cell lymphoma: analysis of 134 cases].

Objective: To investigate the clinicopathological features and prognosis of cytotoxic T-cell lymphoma (CTL). Methods: The clinicopathological data of 134 CTL patients in Beijing Friendship Hospital Affiliated to Capital Medical University, the 989 Hospital of PLA Joint Logistics Support force (formerly the 152 Hospital) and the Fourth Hospital of Hebei Medical University from 2008 to 2020 were retrospectively collected. Immunophenotype, Epstein-Barr virus infection status and T cell receptor (TCR) clonality of tumor cells were assessed, and clinicopathological features and prognosis of patients were analyzed. Results: Among the 134 CTL patients, the male to female ratio was 1.7∶1.0, the median age was 49.5 years (range 3-83 years), and 100 cases (74.6%) were under 60 years old. Forty-six point nine percent of the patients (53/113) had B symptoms. Most of the patients presented with systemic superficial lymphadenopathy. According to the Ann Arbor staging system, 36.8% (39/106) of the patients were in stage Ⅰ-Ⅱ, and 63.2% (67/106) in stage Ⅲ-Ⅳ. The rate of extranodal involvement was 51.6% (66/128). Spleen was involved in 24.2% (31/128) of the cases. Morphology showed diffuse growth of abnormal lymphocytes, infiltrating and destroying normal tissue structure. Immunohistochemical staining showed that tumor cells expressed T cell antigens (CD2, CD3, CD5, and CD7), and 72.0% (77/107) of them had decreased or lost expression of one or more antigens. According to the numbers of CD4 and CD8 expression in tumor cells, 70 cases (52.2%) were grouped into CD8+>CD4+group. The expression rates of TIA-1 and granzyme B were 99.2% (119/120) and 79.8% (95/119), respectively. CD20 abnormal expression rate was 27.6% (37/134) and CD56 was negative in all cases. The median Ki-67 proliferative index was 45.0% (range 5%-80%). In situ hybridization of small RNA encoded by Epstein-Barr virus was negative. Clonal TCR gene rearrangement analysis was performed on 49 cases and was positive in all cases. Ninety-one patients were followed up for a median of 36 months (range, 1 to 240 months), and 40 of the 91 patients (44.0%) died. The twenty-three patients were in complete remission (including 13 cases with localized single extranodal mass). The 3-year and 5-year overall survival rates were 53.5% and 49.4%, respectively. Univariate analysis showed that B symptom, spleen involvement, extranodal involvement, clinical stage, CD8+>CD4+phenotype, abnormal expression of CD20 and Ki-67 proliferation index (>60%) were associated with overall survival (P<0.05). The multivariate Cox regression analyses showed that spleen involvement and CD8+>CD4+ phenotype were independent prognostic factors for overall survival in CTL patients. Conclusions: CTL are more commonly found in adult males under 60 years old, often accompanied by B symptom, with a high proportion of extranodal involvement and more CD8 positive phenotypes. Spleen involvement and CD8+>CD4+phenotype are independent predictors of CTL overall survival. Some patients with localized extranodal CTL may have a good prognosis.

[Clinicopathological features of angioimmunoblastic T-cell lymphoma pattern â ].

Objective: To investigate the clinicopathological features of angioimmunoblastic T-cell lymphoma pattern Ⅰ (AITL Pattern Ⅰ). Methods: The clinicopathological data of 11 AITL Pattern Ⅰ cases that were diagnosed at the Beijing Friendship Hospital Affiliated to Capital Medical University (10 cases) and Beijing Lu Daopei Hospital (1 cases) from January 2019 to October 2021 were retrospectively collected. Immunophenotype, Epstein-Barr virus infection status and T cell receptor (TCR) clonality of the tumor cells were tested, and clinicopathological features of cases were analyzed. Results: Among the 11 AITL Pattern Ⅰ cases, the male to female ratio was 1.2∶1.0. The median age was 59 years (range 47-78 years). Seven cases had B symptoms, while eleven cases presented with systemic lymphadenopathy. According to Ann Arbor system staging, two cases were classified as stage Ⅰ-Ⅱ, and 9 cases as stage Ⅲ-Ⅳ. Hepatosplenomegaly was present in two cases (2/11), three cases (3/11) had skin rash and pruritus, and two cases (2/11) had pleural effusion. Previously, 6 cases (6/11) were diagnosed as reactive hyperplasia, 1 case (1/11) as EBV-associated lymphoproliferative disorder, and 4 cases (4/11) as hyperplasia of lymphoid tissue, which was unable to exclude lymphoma. Histologically, all the 11 cases showed hyperplastic follicles in the paracortical regions with well-formed germinal centers. The hyperplastic follicles showed ill-defined borders and attenuated mantle zones in 7 cases. Mantle zones completely disappeared in 4 cases. The follicles were surrounded by a thin layer of atypical lymphocytes with bright or faintly stained cytoplasm. In 2 cases, the clear cells were located between the germinal centers and the thin residual mantle cell layers, showing a circular growth pattern. The cells were medium in size, with irregular karyotype, coarse chromatin and indistinct nucleoli. Immunohistochemically, CD21 staining showed that the meshworks of follicular dendritic cells(FDC)were mainly confined to the follicles. There was a subtle expansion of the meshworks of FDC in 4 cases with ill-defined borders. The atypical cells surrounding the follicles expressed CD3 (11/11), CD4 (11/11), PD-1 (11/11), CXCL13 (6/11), ICOS (10/11) and CD10 (7/11). PD-1 staining showed a strong perifollicular pattern, and a small number of positive cells were scattered around the high endothelial veins in the interfollicular region. CXCL13, ICOS and CD10 showed similar distribution patterns. EBV-encoded small RNA probe (EBER) in situ hybridization showed that EBER positive B lymphocytes were scattered in the interfollicular region (5-20/HPF) in all cases. T cell receptor gene rearrangement was monoclonal in all cases. Conclusions: Diagnosing AITL Pattern Ⅰ may be challenging and requires comprehensive analysis of clinical manifestations, histological morphology, immunophenotype and gene rearrangement results.

[Singleton placentas with abnormal shape: a clinicopathological analysis of 130 cases].

Objective: To investigate the pathological characteristics of singleton placenta with abnormal shape and its influence on the outcome of maternal-fetal pregnancy. Methods: The clinicopathological data of singleton placentas with abnormal shape from January 2014 to December 2020 in the Department of Pathology, Haidian Maternal and Children Health Hospital were analyzed retrospectively. Results: There were 130 singleton placentas with abnormal shape in this cohort, including 48 succenturiate placentas, 12 bilobed placentas, 50 marginate placentas, 13 circumvallate placentas, 3 annular placentas, 2 membranous placentas and 2 fenestrated placentas. Gestational age ranged from 29+5 to 40+4 weeks. There were 51 cases of premature rupture of membranes, 11 cases of placenta previa, 5 cases of placental abruption, 15 cases of placental adhesion/implantation and 27 cases of postpartum hemorrhage. There were 46 preterm fetuses,28 fetuses with fetal growth restriction, 22 fetuses with intrauterine distress, and 1 fetus with intrauterine death. Grossly, the placental lobules of succenturiate placentas had apparent size difference, while two lobules of bilobate placenta were more consistent. The chorionic plate size was smaller than the bottom plate of circumvallate placenta, the folded fetal membrane in the rim of placenta was thickened (termed marginate placenta if there was no thickening). The membranous placenta was characterized by a thin, large membrane-like shape. Annular placenta showed characteristic hollow cylinder, ring or horseshoe-shape. Fenestrated placenta was characterized by tissue defects near central area. Microscopically, functional/morphologic changes were the main manifestations of inadequate maternal-fetal perfusion, including villous infarction, distal villous dysplasia and excessive villous maturation. Conclusions: The abnormal shaped singleton placentas showed variable extent of inadequate maternal-fetal perfusion, which may lead to adverse pregnancy outcomes such as premature delivery, fetal growth restriction, intrauterine distress or fetal death.

[Autopsies and placental examinations of perinatal fetal deaths: a clinicopathological analysis of 105 cases].

Objective: To summarize the clinicopathological factors related to perinatal fetal death and to evaluate importance of fetal autopsy and placental pathology. Methods: The clinicopathological data of 105 perinatal fetal deaths in Beijing Haidian Maternal and Child Health Hospital from November 2012 to December 2020 were retrospectively analyzed. Relevant literature was also reviewed. Results: The maternal age of the deceased fetuses ranged from 22 to 43 years with the average (31.35±4.04 years), and the gestational weeks were 28-40+6 weeks. Among them, 101 were singleton cases and 4 twin cases. 103 fetuses died in uterus and 2 died during delivery. Relevant factors analysis of the 105 perinatal fetal deaths showed that 86 cases (81.9%, 86/105) were related to umbilical cord/placental abnormality, 10 cases (9.5%, 10/105) uterine infection, 6 cases (5.7%, 6/105) fetal factors, 1 case was fetal maternal blood transfusion syndrome, 1 case twin blood transfusion syndrome, and 1 case died of complete uterine rupture. Among the 86 cases related to umbilical cord/placental abnormality, the diagnosis was most often based on the gross examination of placenta. The most common cause of death was umbilical cord torsion with thin root, followed by placental abruption, tight umbilical cord winding, vascular rupture and umbilical cord true knot. The morphology of placenta revealed mainly functional changes. Among the 10 cases related to intrauterine infections, the placenta generally showed lobular placental edema. The morphological characteristics of ascending infection were mainly acute chorioamnionitis, and the morphological characteristics of blood-borne infection were mainly acute or chronic villitis, as well as villous interstitial inflammation. Identification of viral inclusions suggested viral etiology, while the final diagnosis was relied on laboratory testing. Among the 6 cases related to fetal abnormality, the diagnostic value of placenta was limited and the diagnosis could be made with fetal autopsy. Conclusion: The causes of perinatal fetal death are complex, diverse, and often the synergistic result of multiple factors. Fetal autopsy and placental pathology are the key technical means to identify the cause of death and deserve more attention and utilization.

[Clinicopathological features and prognosis of high-grade B-cell lymphoma with MYC and bcl-2 and/or bcl-6 rearrangements].

Objective: To investigate the clinicopathological characteristics and prognosis of high-grade B-cell lymphoma (HGBL) involving combined rearrangements of MYC, bcl-2 and bcl-6. Methods: A total of 1 138 cases of large B cell lymphoma (LBL) that were treated at the Ruijin Hospital Affiliated to Shanghai Jiaotong University School of Medicine from January 2017 to September 2020 were analyzed using fluorescence in situ hybridization (FISH) with probes against MYC, bcl-2 and bcl-6. The clinical and pathological data of the 45 patients with HGBL that had rearrangements of MYC and bcl-2 and/or bcl-6 were collected and retrospectively analyzed. Results: Among the 1 138 LBL, 45 (4.0%) cases had combined rearrangements of MYC, bcl-2 and/or bcl-6 that included 6 HGBL cases with MYC, bcl-2 and bcl-6 rearrangements, 14 HGBL cases with MYC and bcl-2 rearrangements, and 25 HGBL cases with MYC and bcl-6 rearrangements. Of these 45 patients, 29 patients were male, and 16 patients were female, aged 29 to 83 years. HGBL with MYC, bcl-2 and bcl-6 rearrangements and HGBL with MYC and bcl-2 rearrangement were reclassified as the germinal center B-cell (GCB) subtype using the Hans algorithm. HGBL with MYC and bcl-6 rearrangement were reclassified as the GCB subtype (68.0%) and the non-GCB subtype (32.0%). The vast majority of HGBL cases had a high Ki-67 proliferation index. Most HGBL patients had advanced stage disease with a high IPI score and an increased LDH level. Also, some patients had clinical features including elevated plasma ß2-microglobulin levels, B symptoms, and bone marrow involvement. The IPI scores and LDH levels were significantly different between the HGBL cases with MYC, bcl-2 and bcl-6 rearrangements and the HGBL cases with MYC and bcl-6 rearrangements (P<0.05). Compared with the HGBL cases with MYC, bcl-2 and bcl-6 rearrangements, the HGBL cases with MYC and bcl-2 or bcl-6 rearrangements had a lower incidence of bone marrow involvement (P<0.05). There were no significant differences in the prognosis among HGBL cases with MYC, bcl-2 and bcl-6 rearrangements, the cases with MYC and bcl-2 rearrangements, and the cases with MYC and bcl-6 rearrangements (P>0.05). Conclusions: HGBL with MYC, bcl-2 and/or bcl-6 rearrangements are rare types of B-cell lymphoma with high degree of malignancy and have a short overall survival. To reduce misdiagnosis and improve diagnostic accuracy, it is necessary to assess the patients' clinical features and conduct histopathological, immunohistochemical and FISH analyses.

[Translocations of MYC, bcl-2 and bcl-6 genes and Epstein-Barr virus infection in primary cardiac large B-cell lymphoma].

Objective: To investigate the translocations of MYC, bcl-2 and bcl-6 genes, the Epstein-Barr virus (EBV) status and the clinicopathological features of primary cardiac large B cell lymphoma (LBCL). Methods: Seven cases of primary cardiac LBCL were collected at Beijing Friendship Hospital, Capital Medical University, China from February 2013 to May 2019. The clinical feature, pathological morphology and immunophenotype were analyzed. The detections of EBV and gene rearrangements of MYC, bcl-2 and bcl-6 were conducted. The 2017 WHO classification of tumors of haematopoietic and lymphoid tissues was used to classify the tumors. Results: Four patients with right atrial lesions showed diffuse infiltration of medium size lymphoid cells with small vascular hyperplasia, without evidence of EBV infection. Without detectable gene rearrangements of MYC and bcl-2, 2 of the patients showed bcl-6 gene break-apart. The diagnosis was revised from diffuse LBCL to high-grade B-cell lymphoma, not otherwise specified (HGBL-NOS). There was a case of CD5+ diffuse LBCL involving the right atrium and ventricle and 2 cases of fibrin-associated diffuse LBCL located at left atrium without gene rearrangements of MYC, bcl-2 and bcl-6. However, EBER and EBNA2 were highly expressed in fibrin-associated diffuse LBCL. The patients were followed up for 10-71 months. Four cases of HGBL-NOS and a case of CD5+ diffuse LBCL received R-CHOP with/without autologous stem cell transplantation. All but two patients survived. Two cases of fibrin-associated diffuse LBCL were disease free without adjuvant chemotherapy and radiotherapy. Conclusions: Primary cardiac LBCL is heterogeneous, including at least HGBL-NOS. Primary cardiac HGBL-NOS most frequently occurs in the right atrium. Tumor cells of primary cardiac LBCL have the morphological characteristics similar to Burkitt lymphoma, lacking MYC and bcl-2 gene rearrangements, but usually show bcl-6 gene disruption. Fibrin-associated diffuse LBCL has a good prognosis and postoperative chemotherapy seems unnecessary.

[Clinicopathological features and prognosis of the skeletal-muscle cytotoxic T-cell lymphoma].

Objective: To investigate the clinicopathological features and prognosis of skeletal-muscle cytotoxic T-cell lymphoma (CTL). Methods: The clinical data of 14 cases of skeletal muscle CTL and 47 cases of non-skeletal muscle extranodal CTL patients in Beijing Friendship Hospital Affiliated to Capital Medical University and the 989 Hospital of the joint logistics support force of the people's Liberation Army (the former 152 hospital) from 2008 to 2019 were collected retrospectively. Immunophenotype, EBV infection status and T-cell receptor (TCR) clonality of tumor cells were evaluated. The clinicopathological features and prognosis of the two groups were compared. Results: Skeletal-muscle CTL accounted for 23.0% (14/61) of extranodal CTL in the same period. The median age of the patients was 42.3 years (range 11-76 years), including six males and eight females. The main clinical manifestations were painless masses. Two patients (2/14) had B symptoms. The tumors occurred in the cheek (7 cases), the tongue (4 cases), the lower lip (3 cases) and the left upper arm (2 cases), and in two cases had two sites. Ten cases were of stage ⅠE and four cases stage ⅡE. Compared with non-skeletal-muscle extranodal CTL, many patients of skeletal-muscle CTL did not have B symptoms, the clinical stage was lower, and the tumor mainly involved the oral cavity (cheek, tongue and lip, P<0.05). Morphologically, the tumor showed diffuse infiltration of heterotypic lymphocytes in skeletal muscle. Immunohistochemistry showed that in 11/14 cases, there were reduced or loss of expression of some the T cell antigens (CD2, CD3, CD5, CD7). TIA-1, Gr B and CD8 (CD8+>CD4+) were expressed in all cases, and CD56 was negative. The median Ki-67 proliferation index was 35.0% (range 5%-60%). EBER in situ hybridization was negative in all cases. The results of TCR clonality analysis showed clonal TCR gene rearrangement were detected in eight cases. The median follow-up time was 40 months (range 10-67 months). Ten patients were tumor free; the 5-year survival rate of skeletal-muscle CTL was 100%. Compared with non-skeletal-muscle extranodal CTL (5-year overall survival rate was 35.9%), the difference was statistically significant (χ²=8.277, P=0.004). Conclusions: Skeletal-muscle CTL mostly occurs in the skeletal muscle of cheek and mouth. Tumor cells show morphologic characteristics of muscle invasion and myositis-like feature. It also shows CD8+>CD4+immunophenotype, cytotoxic molecular pattern and is associated with low clinical stage and good prognosis.

[Clinicopathological characteristics of pediatric-type follicular lymphomas: an analysis of 37 cases].

Objective: To study the clinicopathologic features, immunophenotype and prognosis of pediatric-type follicular lymphoma (PTFL). Methods: Thirty-seven cases of PTFL at the Beijing Friendship Hospital, Capital Medical University, from January 2012 to March 2018 were analyzed using light microscopy, immunohistochemistry, and polymerase chain reaction (PCR), and 13 cases were also examined using fluorescence in situ hybridization (FISH). Results: The male to female ratio was 35∶2. The median age was 16 years. Thirty-one patients were clinical stage Ⅰ and 6 were stage Ⅱ, displaying enlargement of lymph node in the head and neck regions. Follow-up information was available in 32 patients. Only two patients received low-dose chemotherapy, and none of these patients had relapse or disease progression at the latest follow-up (ranging from 16 to 79 months; median, 37 months). Morphologically, the lymph node architecture was partially or totally effaced by expansile follicles lacking polarization, with a prominent "starry sky" appearance. The cytologic composition was dominated by monotonous medium to large-sized blastoid cells with round to oval nuclei, finely clumped chromatin, small nucleoli, and scant cytoplasm. Immunophenotypically, all cases were positive for CD20, CD10, and bcl-6, but negative for bcl-2, MUM1 and C-MYC. Tumor cells were restricted to the follicles. The Ki-67 immunohistochemistry demonstrated a high proliferation (50% to 90%). Moreover, the tumor cells in the examined 28 cases were negative for CD43, CD5 and CD23. PCR analysis revealed monoclonal Ig gene rearrangements in all specimens. Thirteen cases being subjected to the FISH testing lacked bcl-2 and bcl-6 translocations. Conclusion: PTFL is different from conventional follicular lymphoma in their distinct morphology, immunophenotypic and molecular features, and behaves like an highly indolent or benign tumor.

[miRNA-96-5p inhibits the proliferation and migration of gastric cancer cells by targeting FoxQ1].

Objective: To investigate the role of microRNA-96-5p in the proliferation and invasion of gastric cancer cells and its molecular mechanism. Methods: From June 2015 to January 2017, 53 resected specimens were collected. The transcriptional levels of microRNA-96-5p and forkhead box Q1 (FoxQ1) in gastric cancer tissues and the matched para-cancerous tissues were quantified by quantitative real-time PCR (qRT-PCR). The expression of FoxQ1 protein was also detected by immunohistochemistry (IHC). The relationship between microRNA-96-5p expression and the clinicopathological features of gastric cancer and its correlation with FoxQ1 expression were analyzed. The expressions of miRNA-96-5p in gastric cancer tissue and adjacent normal tissue were detected by qRT-PCR. miRNA-96-5p mimics was transfected to BGC-823 gastric cancer cells. The effects of miRNA-96-5p on cell proliferation and invasion were detected by cell counting kit-8 (CCK-8) assay and Transwell assay, respectively. The protein expressions of FoxQ1, E-cadherin and vimentin were determined by western blot. The relationship between FoxQ1 and miRNA-96-5p expressed in BGC-823 cells was detected by dual-luciferase reporter assay. Results: The median expression of miRNA-96-5p in gastric cancer tissue was 1.05, significantly lower than 3.23 of para-cancerous tissues (P<0.05). The positive rate of FoxQ1 expression in gastric cancer tissue was 71.7%, significantly higher than 28.3% of para-cancerous tissues (P<0.05). The expression of FoxQ1 was negatively corelated with the level of miRNA-96-5p (r=-0.613, P=0.006). The expression of miRNA-96-5p in gastric cancer cell BGC-823 was significantly decreased compared with normal gastric epithelial cell (0.96±0.08 vs 2.84±0.15, P<0.05). The results of CCK-8 assay and Transwell assay showed that overexpression of miRNA-96-5p significantly reduced the proliferation and invasion abilities of gastric cancer cells (P<0.05). Overexpression of miRNA-96-5p decreased the protein level of FoxQ1. Moreover, it upregulated the expression of E-cadherin and downregulated the expression of vimentin. The result of dual-luciferase-3'-UTR reporter assay confirmed that miRNA-96-5p binds to the 3'UTR of FoxQ1. Conclusion: miRNA-96-5p may suppress the proliferation, migration and epithelial-mesenchymal transition (EMT) of gastric cancer cell by down-regulation of FoxQ1.

[Clinicopathological features of long-term tumor-free survival of patients with untreated primary tonsillar diffuse large B-cell lymphoma].

Objective: To investigate the clinicopathological features of long-term tumor-free survival in patients with untreated primary diffuse large B-cell lymphoma (DLBCL) of the tonsil. Methods: The study included 80 consultation cases of primary tonsillar DLBCL from April 2006 to July 2017 in the Department of Pathology, Beijing Friendship Hospital, Capital Medical University. The patients were divided into two groups: experimental groups of 10 untreated patients with long-term tumor-free survival, and 70 patients who had been treated (control group). The clinical data, histopathological features, immunohistochemical staining, and molecular biology test results of the patients were analyzed retrospectively. Results: Patients who had long-term tumor-free survival with untreated primary diffuse large B-cell lymphoma had the disease mostly confined to the tonsil. Biopsy showed that the tonsil structure was only partially effaced and the lesions were relatively "fresh". EBER and FISH test for t (14;18) results were negative. Gene rearrangement detection showed monoclonality. There was statistically significant difference between the age, bcl-2 expression, CMYC protein expression and co-expression of CMYC and bcl-2 between the untreated group and the treated group(P<0.05). Patient gender, tumor site, histological type and clinical stage showed no difference between the untreated group and the treated group (P>0.05); The median overall survival of the untreated group and treated group was 81 months and 20 months, respectively, and the difference was not statistically significant (P>0.05).In patients younger than 40 years of age, the untreated group had a statistically significant difference in primary site and CMYC protein expression compared with the treated group (P<0.05), and there was no statistical significance in other aspects. Conclusions: Long-term tumor-free survival patients with untreated tonsillar primary DLBCL have relatively unique clinical characteristics. There is no significant difference in the prognosis between the untreated and treated groups, indicating radiotherapy and chemotherapy may not be required and therefore, avoiding related side effects.

[Paediatric nodal marginal zone lymphoma: a clinicopathological study of seven cases].

Objective: To investigate the pathological features and clinical manifestation of pediatric nodal marginal zone lymphoma(NMZL). Methods: Histological morphology and immunophenotype of 7 cases of pediatric NMZL were retrospectively reviewed at Beijing Friendship Hospital Affiliated to Medical University between January 2008 to October 2018. Clonal rearrangement analysis was performed. Clinical information including patient follow-up data were analyzed. Results: All 7 patients were male with a median age of 15 years aged from 10 to 26 years. All patients presented with only lymph node enlargement without B symptoms, including cervical lymph node (5 cases), preauricular lymph node (1 case) and retroauricular lymph node (1 case). Histologically, all cases showed irregular large follicles on the edges with widened marginal areas and intervesicular areas, and lesional cells were uniform with progressive transformation of germinal center centers along with a small amount of intrinsic lymphoid tissue. All 7 cases showed diffuse CD20 positivity both follicle and interfollicular region along with 30%-40% positivity in the interfollicular region (pathological region). Markers of other B-cell lymphomas werenot expressed. All 7 cases were positive for immunoglobulin(Ig) gene rearrangement. None of the patients showed no recurrence up on after follow-up for an average of 13 months. Conclusions: Pediatric NMZL is a rare type of lymphoma that has a unique morphology and occurs almost exclusively in male children and young adults and often in head and neck lymph nodes. It has an excellent prognosis. Therefore, awareness of the disease with accurate diagnosis is important.

[Primary testicular NK/T cell lymphoma: a clinicopathologic analysis of six cases].

Objective: To evaluate the clinicopathological features, diagnosis and management of primary testicular NK/T cell lymphoma (NKTCL). Methods: Six cases of primary testicular NKTCL at Beijing Friendship Hospital, Capital Medical University from January 2007 to December 2016 were retrospectively analyzed for the morphology, immunephenotype and outcome, and relevant literature was reviewed. Results: The median age of patients at diagnosis was 45 years(range 32-65 years). All patients presented with testicular masses as initial symptoms (6/6), five cases (5/6) were on the right. The lesions were confined to the testis. All patients were classified as Ann Arbor stage Ⅰ but the tumors exhibited aggressive clinical behavior. Two patients died of the disease within two months, three (3/6) had clinical remission, and one (1/6) was lost to follow-up. Morphologically, the lymphoma cells showed a diffuse growth pattern that largely effaced the interstitial tissues, and surrounded seminiferous tubules in all cases. There was also a prominent angioinvasive pattern, with focal necrosis and karyorrhexis(4/6). Cytologically, the medium-sized neoplastic cells showed scanty to moderate amount of cytoplasm and irregular folded nuclei. The immunophenotype was similar to that of nasal NKTCL: the neoplastic cells were positive for cytoplasmic CD3, CD56, cytotoxic molecules and EBV-encoded small RNA, the loss of CD5 antigen was seen in all cases. Conclusions: Primary testicular NKTCL is extremely rare, highly aggressive and is associated with a poor prognosis. There is no unified standard of treatment. Thus, at the time of diagnosis of testicular lymphoma, NKTCL should be included in the differential diagnosis.

[Cut-off value of Ki-67 labeling index in the pathologic grading of follicular lymphoma].

Objective: To determine the cut-off values of Ki-67 labeling index (LI) in the histological grading of follicular lymphoma (FL). Methods: Clinicopathological data of 350 FL patients diagnosed at Beijing Friendship Hospital from June 2014 to January 2016 were analyzed retrospectively by quantitative evaluation and statistical analysis of Ki-67 LI. Results: Of the 350 patients with FL, the male and female ratio was 1.1 and the average age was (50.2±14.0) years with a median age of 51 years (range 4 to 82 years). The tumors were graded as grade Ⅰ-Ⅱ in 215 cases (61.4%), grade Ⅲ A in 105 cases (30.0%), and grade Ⅲ B in 30 cases (8.6%). The average Ki-67 values were (22.8%±8.3%) for the FL low (grade Ⅰ-Ⅱ) and (50.4%±10.7%) for high grade (Ⅲ A and Ⅲ B) and were statistically significant by Mann Whitney U test (P<0.01). Receiver operated characteristic curve analysis showed that the best diagnostic cut-off value of low grade FL was 35% (sensitivity of 96.3% and specificity of 93.3%) with the largest area under curve (AUC=0.990, P<0.01, 95%CI for 0.982-0.998). According to the analysis of four lattice diagnostic tests, Ki-67 LI >40% was an important factor (χ2=230.733, P<0.01) in predicting high grade FL. When the cut-off value of Ki-67 LI was set at 40%, high grade LF could be diagnosed with the greatest sensitivity (98.1%) and specificity (87.7%). Moreover, a significant correlation between the Ki-67 LI and the pathological grade of FL (r=0.836, P<0.01) was observed. Conclusions: Ki-67 LI of below a cut-off value of 35% is a reliable indicator of low grade FL.Ki-67 over 40% is consistent with high grade FL. These Ki-67 cut-off values may serveas an important auxiliary indicator in the grading of FL.

[Clinicopathologic features and prognosis of gastrointestinal mantle cell lymphoma].

Objective: To investigate the clinicopathologic features and prognosis of gastrointestinal mantle cell lymphoma (GI-MCL). Methods: Clinical data of 38 GI-MCL patients diagnosed at Beijing Friendship Hospital from January 2002 to January 2016 were retrospectively reviewed morphologically and immunophenotypically. IgH/CCND1 gene fusion was assessed by fluorescent in situ hybridization (FISH). For comparison, 60 cases of non-GI-MCL were randomly selected to extract the differences inclinicopathological features and patient survival between the two groups. Results: Of 38 patients with GI-MCL, the median age was 62 years (range: 35-78 years, 23 males and 15 females), of which patients of 60 years of age or older accounted for 55.3%. Patients with clinical course of less than 6 months accounted for 81.1%(30/37). The main symptoms included abdominal pain, diarrhea, anorexia and hematochezia. Those with B symptoms accounted for 32.4%(12/37). The tumor most often involved lleocecal region (57.9%, 22/38), followed by rectum (36.8%, 14/38) and sigmoid colon (28.9%, 11/37), and the stomach accounted for 18.4%(14/38). Endoscopic polypoid lesions were found in 33 cases (86.8%, 33/38), of which 22 cases (66.7%, 22/33) were multiple. Five cases (13.2%, 5/38) presented with local protuberant neoplasm. According to Ann Arbor staging, 3 cases (7.9%, 3/38) were at stage Ⅰ, 4 cases (10.5%, 4/38) were at stage Ⅱ, and 31 cases (81.6%, 31/38) were at stage Ⅳ. The number of patients with tumor involvement of abdominal and retroperitoneal lymph nodes accounted for 45.7%(16/35), including 41.7%(15/36) involving the superficial lymph node, 17.1%(6/35) involving extranodal sites, and 23.5%(8/34) having splenomegaly. All of the 38 cases were classic MCL, and the tumor was composed of uniform lymphoid cells and effacing normal mucosal structure. All tumors were positive for CD20 and CD5. 97.4% (37/38) tumors were positive for cyclin D1, and 92.0% (23/25) tumors were positive for SOX11. FISH test was positive in 1 case of cyclin D1 negative tumor. Twenty-eight patients (73.7%) had a median follow-up of 25.0 months (range: 3-79 months). The 3-year survival rate for stage Ⅰ-Ⅱ and stage Ⅲ-Ⅳ of patients were 80.0% and 69.1%, respectively (P> 0.05). The 3-year survival rate for GI-MCL and non-GI-MCL patients were 71.7% and 72.5%, respectively (P>0.05). Single factor analysis showed that age of >60 years and splenomegaly were correlated with a worse overall survival rate (P<0.05). Conclusions: Gastrointestinal malaise is the most common presenting symptom in GI-MCL patients. GI-MCL more commonly involves colorectum with more frequent multiple polypoid lesions. Patients of age >60 years and with splenomegaly have poor prognosis. There is no difference in the prognosis between GI-MCL and non-GI-MCL patients.