Primary synovial sarcoma of lung: a clinicopathological analysis of 12 cases / 中华病理学杂志

Objective: To investigate the clinicopathological features, immunophenotype, molecular features and differential diagnosis of primary synovial sarcoma of the lung (PSSL). Methods: Twelve cases of PSSL were collected at Henan Provincial People's Hospital, during May 2010 and April 2021, and their clinicopathological parameters were summarized. SS18-SSX, H3K27Me3, and SOX2 were added to the original immunomarkers to evaluate their diagnostic value for PSSL. Results: The age of 12 patients when diagnosed ranged from 32 to 75 years (mean of 50 years). There were 7 males and 5 females, 2 left lung cases and 10 right lung cases. Of the 6 patients who underwent surgical resection, five cases were confined to lung tissue (T1), one case had mediastinal invasion (T3), two cases had regional lymph node metastasis (N1), and none had distal metastasis. Microscopically, 11 cases showed monophasic spindle cell type and one case showed biphasic type composed of mainly epithelial cells consisting of cuboidal to columnar cells with glandular and cribriform structures. It was difficult to make the diagnosis by using the biopsy specimens. Immunohistochemistry (IHC) showed CKpan expression in 8 of 12 cases; EMA expression in 11 of 12 case; TLE1 expression in 8 of 12 cases; S-100 protein expression in two of 12 cases; various expression of bcl-2 and vimentin in 12 cases, but no expression of SOX10 and CD34 in all the cases. The Ki-67 index was 15%-30%. The expression of SS18-SSX fusion antibody was diffusely and strongly positive in all 12 cases. SOX2 was partially or diffusely expressed in 8 of 12 cases, with strong expression in the epithelial component. H3K27Me3 was absent in 3 of 12 cases. SS18 gene translocation was confirmed by fluorescence in situ hybridization (FISH) test in all 12 samples. Six cases underwent surgery and postoperative chemotherapy, while the other six cases had chemotherapy alone. Ten patients were followed up after 9-114 months, with an average of 41 months and a median of 26 months. Five patients survived and five died of the disease within two years. Conclusions: PSSL is rare and has a broad morphological spectrum. IHC and molecular tests are needed for definitive diagnosis. Compared with current commonly used IHC markers, SS18-SSX fusion antibody has better sensitivity to PSSL, which could be used as an alternative for FISH, reverse transcription-polymerase chain reaction or next generation sequencing in the diagnosis of PSSL.

Clinicopathological features of mature T/NK cell lymphoma with aberrant CD20 or CD79α expression / 中华病理学杂志

Objective: To investigate the clinicopathological characteristics and prognosis of mature T/NK cell lymphomas with aberrant CD20 or CD79α expression. Methods: A retrospective analysis of 641 cases of mature T/NK cell lymphoma diagnosed from January 2014 to December 2020 was performed, and 14 cases of CD20-positive and one case of CD79α-positive mature T/NK-cell lymphoma were identified. Histological examination, immunohistochemical characterization, in situ hybridization for Epstein-Barr virus encoded early RNA (EBER), and PCR testing for immunoglobulin and T cell receptor (TCR) gene rearrangements were performed. Clinicopathological characteristics of these lymphomas were analyzed. Results: There were 13 males and 2 females, with a median age of 56 years. There were 8 cases of peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS), 3 cases of extranodal NK/T-cell lymphoma, nasal type (ENKTCL), 2 cases of monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL) and 2 cases of angioimmunoblastic T-cell lymphoma (AITL). Twelve cases were stage Ⅲ or Ⅳ lymphomas. The prognosis was overall poor. The histology, immunophenotype and TCR gene rearrangement were not significantly different from the corresponding types of lymphoma. Ki-67 proliferation index was over 70% in all cases. The expression of CD20 or CD79α was weak and heterogeneous. All 15 case of Ig gene rearrangement were polyclonal. Conclusions: Mature T/NK cell lymphoma with abnormal expression of CD20 or CD79α is rare, commonly found in advanced stage, and associated with poor prognosis. The expression of CD20 or CD79α in these cases is weaker than the corresponding mature T/NK cell lymphomas, while its proliferation index is higher. Histomorphology, extensive immunoprofiling and molecular detection are required for accurate diagnosis.

Clinicopathological features and BRAF V600E and MYD88 L265P mutation status of nodal marginal zone lymphoma / 中华病理学杂志

Objective: To investigate the clinicopathological features as well as BRAF V600E and MYD88 L265P mutation status of nodal marginal zone B cell lymphoma (NMZL). Methods: Thirty-two cases of NMZL were diagnosed from September 2009 to February 2021 at the Henan Provincial People's Hospital and Peking University School of Basic Medical Sciences. The clinicopathologic characteristics were obtained and analyzed. BRAF V600E and MYD88 L265P mutation status were identified using PCR and Sanger sequencing, respectively. Results: There were 20 males and 12 females patients with a median age of 69 years (ranging 36-82 years). The most prevalent clinical manifestation was multiple lymph nodes enlargement in head and neck (22/32, 68.8%), followed by inguinal (12/32, 37.5%), axillary (11/32, 34.4%), mediastinum (5/32, 15.6%) and retroperitoneal lymph nodes (4/32, 12.5%). Most of the patients were in Ann Arbor stage Ⅰ/Ⅱ (21 cases). The morphologic features included diffuse (24/32, 75.0%), nodular (5/32, 15.6%), interfollicular (2/32,6.3%) and perifollicular (1/32,3.1%) types. The tumor cells showed monocyte-like, centrocyte-like, small lymphocyte-like and plasma cell-like differentiation. Immunophenotyping revealed diffuse expression of CD20 in all tumor cells, whereas CD43 (11/32, 34.4%), bcl-2 (20/32, 62.5%), MNDA (13/32, 40.6%) and CD5 (2/32, 6.3%) were partially expressed. Ki-67 proliferation index varied from 10% to 40%. BRAF V600E mutation was found in two cases (2/32, 6.3%), but MYD88 L265P mutation was not detected. Eighteen patients survived and three died at the end of follow-up period which ranged 6 to 110 months. Conclusions: The morphologic features of NMZL varies across individuals, it should be differentiated from various B-cell lymphomas; however immunological biomarkers with high specificity for NMZL are still lacking. No MYD88 L265P mutation is found in NMZL. Some cases may harbor BRAF V600E mutation and yet the prevalence remains indeterminate; further researches are warranted.

Calcifying fibrous tumor: a clinicopathological analysis of 32 cases / 中华病理学杂志

To investigate the clinicopathological characteristics, histogenesis, immunophenotypes, molecular genetic characteristics, diagnosis and differential diagnosis of calcifying fibrous tumors (CFT). 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. 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. 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.

Primary subcutaneous lymphomatous granuloma: a case report and review of literature / 临床与实验病理学杂志

Purpose To investigate the clinicopathological features of primary subcutaneous lymphomatoid granulomatosis (LYG). Methods A case of primary subcutaneous LYG was observed by analysis of the clinical, histological features, immunophenotype and molecular pathology with review of the related literature. Results The male patient, 78-year-old, inadvertently found a mass of right axillary for more than 10 days. The boundary of the mass was clear, it seemed to have a capsule, the cut surface was grayish yellow and grayish red, the texture was medium. A large amount of coagulative necrosis was observed in the center of the mass under microscope. The peripheral area showed a morphological change of panniculitis, accompanied by pleomorphic lymphoid infiltration, showed central and vascular destructive infiltration, pathological mitosis was occasionally observed. Immunophenotyping showed that atypical large lymphoid cells expressed CD45 RB, CD20, CD30, while CD3, CD15, CD56, TIA-1, Granzyme B, ALK, CD21, Langerin and CD1 a, S-100 and CK (AE1/AE3) were negative. The proliferation index of Ki-67 ranged from 50％ to 60％. EBER in situ hybridization showed that positive cells were> 20/HPF.Neither acid fast staining nor TB-DNA testing supported tuberculosis. Molecular pathology found clonal Ig K gene rearrangement, TCRB + TCRG gene rearrangement showed the absence of monoclonal proliferating T cell population. Conclusion The primary subcutaneous LYG is a rare tumor. which can be diagnosed by combination of morphology, immunophenotype and molecular pathology.