Mast Cell Sarcoma of the Retroperitoneum With Concurrent Systemic Mastocytosis and an Undisclosed Associated Hematologic Neoplasm: A Case Report.

Mastocytosis is a rare disorder affecting both children and adults by gathering of functionally defective mast cells in the body's tissues. The World Health Organization (WHO) classified mastocytosis into cutaneous mastocytosis, systemic mastocytosis (SM), and mast cell sarcoma (MCS). We hereby present a case of retroperitoneal MCS with concurrent systemic mastocytosis and an undisclosed associated hematological neoplasm (SM-undisclosed AHN). The diagnosis of MCS and SM was made after the second biopsy over retroperitoneal mass, lymph node, and ovary for rapidly progressive disease with the presentation of unexplained recurrent flushing, palpitation, and shock, in addition to abdominal pain. A clonal myeloid neoplasm was also suspected by the karyotype and hemogram data. Unfortunately, the patient succumbed to the disease quickly. Apart from this unique case, the previously reported cases of SM with MCS in the literature were also reviewed.

Targeted Next-generation Sequencing Reveals a Wide Morphologic and Immunophenotypic Spectrum of Monomorphic Epitheliotropic Intestinal T-Cell Lymphoma.

Primary intestinal T-cell lymphoma (PITL) is highly aggressive and includes celiac disease-related enteropathy-associated T-cell lymphoma (EATL), monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL), and primary intestinal peripheral T-cell lymphoma, not otherwise specified (ITCL-NOS). MEITL is the most common PITL in Asia, comprising of monomorphic medium-sized cells typically expressing CD8, CD56, and cytotoxic granules. Occasional cases with intermediate features between MEITL and ITCL-NOS are difficult to be classified and warrant further investigation. We collected 54 surgically resected PITLs from Taiwan, with 80% presenting with bowel perforation. The overall outcome was poor with a median survival of 7 months. Based on histopathology (monomorphic vs. pleomorphic) and immunophenotype, we classified these cases into 4 groups: MEITL with typical immunophenotype (n=34), MEITL with atypical immunophenotype (n=5), pleomorphic PITL with MEITL-like immunophenotype (n=6), and ITCL-NOS (n=9). There was no EATL in our cohort. Targeted next-generation sequencing of the first 3 groups showed highly prevalent loss-of-function mutations for SETD2 (85%, 80%, and 83%, respectively) and frequent activating mutations for STAT5B (64%, 60%, and 50%, respectively) and JAK3 (38%, 20%, and 50%, respectively). In contrast, ITCL-NOS cases had less frequent mutations of SETD2 (56%) and STAT5B (11%) and rare JAK3 mutations (11%). Our results suggest that there is a wider morphologic and immunophenotypic spectrum of MEITL as currently defined in the 2017 WHO classification. MEITL with atypical immunophenotype and PITL with MEITL-like immunophenotype shared clinicopathologic and molecular features similar to MEITL but distinct from ITCL-NOS, indicating that such cases may be considered as immunophenotypic or histopathologic variants of MEITL.

MMP-10 from M1 macrophages promotes pulmonary vascular remodeling and pulmonary arterial hypertension.

Pulmonary arterial hypertension (PAH) is characterized by muscularized pulmonary blood vessels, leading to right heart hypertrophy and cardiac failure. However, state-of-the-art therapeutics fail to target the ongoing remodeling process. Here, this study shows that matrix metalloproteinases (MMP)-1 and MMP-10 levels are increased in the medial layer of vessel wall, serum, and M1-polarized macrophages from patients with PAH and the lungs of monocrotaline- and hypoxia-induced PAH rodent models. MMP-10 regulates the malignant phenotype of pulmonary artery smooth muscle cells (PASMCs). The overexpression of active MMP-10 promotes PASMC proliferation and migration via upregulation of cyclin D1 and proliferating cell nuclear antigen, suggesting that MMP-10 produced by infiltrating macrophages contributes to vascular remodeling. Furthermore, inhibition of STAT1 inhibits hypoxia-induced MMP-10 but not MMP-1 expression in M1-polarized macrophages from patients with PAH. In conclusion, circulating MMP-10 could be used as a potential targeted therapy for PAH.

Pituitary spindle cell oncocytoma presented as pituitary apoplexy.

Spindle cell oncocytoma is a rare nonfunctioning neoplasm of the adenohypophysis, and was first described in 2002 by Roncaroli et al. In 2007, spindle cell oncocytoma has been categorized as a separate entity by the World Health Organization (WHO) and is classified as a Grade 1 tumor of the central nervous system. Spindle cell oncocytoma of pituitary gland usually occurs in adults and accounts for 0.1-0.4% of all sellar region tumors. Clinically and radiologically, they are indistinguishable from nonfunctioning pituitary adenomas. From 2002 to 2018, approximately 46 cases of spindle cell oncocytoma of pituitary gland had been reported in the English literature and we would like to report a case of 28-year-old woman presented with pituitary apoplexy proved to be a case of spindle cell oncocytoma of pituitary gland which probably will be the 47th reported case.

Mycosis fungoides in Taiwan shows a relatively high frequency of large cell transformation and CD56 expression.

Mycosis fungoides (MF) is an indolent cutaneous T-cell lymphoma and may transform into large cell lymphoma in the disease course. The incidence of MF in Taiwan is lower as compared to that in the West. In this study we aimed to characterise the clinicopathological, immunohistochemical, and genetic features of transformed MF (t-MF) in Taiwan. We retrospectively collected MF cases from April 2004 to April 2015 from four medical centres in Taiwan, reviewed the clinical history and histopathology, and performed immunohistochemistry, in situ hybridisation for EBV (EBER), and fluorescence in situ hybridisation (FISH) for DUSP22/MUM1 gene translocation. Fifty-one specimens from 32 patients with MF were identified with a male to female ratio of 1.5:1 and a median age of 50.5 (range 16-82). Tumours from 11 patients (34%) underwent large cell transformation, with the median age at 61 (range 26-82). The tumour cells of t-MF expressed CD30 and MUM1 in 82% and 100% cases, respectively. CD56 was expressed in two (10%) of 21 MF cases and two (18%) of 11 t-MF cases, respectively; and all four CD56-positive cases were of a helper T-cell phenotype. All CD56 expressing MF and t-MF tumours tested for EBER were negative. FISH study showed rearranged DUSP22/IRF4 in one (9%) of 11 t-MF cases, but not in any of the 19 non-transformed MF specimens. Four patients with t-MF died of disease and six were alive with disease in a median follow-up time of 25 months (mean 44.7 months). Large cell transformation and aberrant CD56 expression were more frequent in patients with MF in Taiwan compared to those in the West. Larger case series and/or national studies are needed to clarify the significance and impact of large cell transformation on the prognosis of patients with MF.

Primary effusion lymphoma in Taiwan shows two distinctive clinicopathological subtypes with rare human immunodeficiency virus association.

AIMS: To investigate the clinicopathological and molecular features of primary effusion lymphoma (PEL) in Taiwan and the association with human immunodeficiency virus (HIV), human herpesvirus 8 (HHV8) and Epstein-Barr virus (EBV). METHODS AND RESULTS: We investigated retrospectively 26 cases with a median age of 76.5. Only one (4%) patient was infected with HIV. Cytologically, all lymphoma cells revealed typical immunoblastic to plasmablastic morphology. Immunohistochemically, HHV8 was positive in eight (32%) tumours and negative in 17 (68%) cases. All 23 tested cases examined were of the non-germinal-centre B cell phenotype. MYC proto-oncogene (MYC) and Epstein-Barr encoding mRNA (EBER) were positive in 43% (nine of 21) and 17% (four of 23) cases, respectively. Immunoglobulin heavy chain (IGH), B cell lymphoma (BCL)2, BCL6 and MYC were rearranged in 71%, 11%, 12% and 18% cases, respectively. By univariate analysis, the overall survival (OS) was associated statistically with MYC expression (P = 0.012) and BCL2 rearrangement (P = 0.035), but not with the others. By multivariate analysis, no factor was statistically significant. Compared to the HHV8-negative cases, the HHV8-positive cases were mainly of the plasmablastic immunophenotype expressing CD30 and CD138, and with a less frequent expression of pan-B cell markers. CONCLUSIONS: Apart from the phenotypical difference, our HHV8-positive neoplasms were not distinct from the HHV8-negative group. Literature review of 256 cases, including our cases, revealed that HHV8-positive cases were associated more frequently with HIV and EBV infection, with rare MYC rearrangement, and a poorer prognosis than HHV8-negative cases. We propose to name the HHV8-positive cases as 'classical' or 'type I PEL' and the HHV8-negative cases as 'type II PEL', stressing the similarities and the distinctive features between these two groups.

Primary cardiac lymphoma with unusual presentation: A report of two cases.

Primary cardiac tumors are rare, with an incidence of 0.056% according to autopsy reports. The most common type is myxoma, while other types, including sarcoma, lipoma, papillary fibroelastoma, rhabdomyoma, fibroma, hemangioma, teratoma, lymphoma and mesothelioma also occur. Primary cardiac tumors usually cause embolization, pericardial effusion and arrhythmia, leading to heart failure. Only 10% of primary cardiac tumors are malignant, approximately 95% of which are sarcomas, while the remaining 5% are cardiac lymphomas and mesotheliomas. The present study reported a case of primary cardiac lymphoma (PCL) with bilateral renal involvement and a case of PCL with bilateral adrenal gland involvement. The prognosis of PCL is poor due to the low rate of early detection and treatment. The definitive diagnosis is dependent on pathology, and timely treatment with chemotherapy can be effective. The two cases developed life-threatening arrhythmia and responded to the initial chemotherapy. In the first case, complete remission was achieved after finalization of therapy. However, the second case refused further chemotherapy and succumbed to his condition after two months.

Dumbbell-Mimicked Mediastinal Angiomatosis.

Angiomatosis is a nonneoplastic proliferative vascular lesion, which occurs mostly in diverse soft tissues. We observed a rare case of mediastinal angiomatosis with intraspinal invasion that mimicked a dumbbell tumor in a 63-year-old man with a history of prostate adenocarcinoma. A roentgenogram of the chest showed that the patient had left pleural effusion and a left paraspinal mass, computed tomography disclosed a low-density fusiform lesion over the left paraspinal region, and magnetic resonance imaging confirmed a large posterior mediastinal tumor with T4 intraspinal invasion. The tumor was completely excised through a laminectomy of the T3-5 spine, followed by thoracoscopic removal of the mediastinal part. The definitive diagnosis was angiomatosis. Surgical removal of such a dumbbell-mimicked tumor is mandatory because it may progress to spinal cord compression.

Primary extranodal natural killer/T-cell lymphoma of bronchus and lung: A case report and review of literature.

Primary pulmonary non-Hodgkin's lymphoma (NHL) is very rare. It represents less than 1% of all NHL, and 0.5-1% of all primary pulmonary malignancies. Almost all cases of primary pulmonary NHL originate from B-cell lineage. We present a case of a 53-year-old man with primary extranodal NK/T-cell lymphoma of the bronchus and lung, presented progressive dyspnea caused by right lower lung consolidation, and pleural effusion. Initial chest computed tomography suggested advanced lung cancer. Bronchofiberscopy showed a polypoid tumor on which a biopsy was performed. Histologically, the diffusely infiltrative atypical cells were positive for cytoplasmic CD3, CD56, granzyme B, and negative for cytokeratin, CD20 immunostains, suggesting NK/T cell lineages. In situ hybridization for Epstein-Barr virus encoded ribonucleic acid (EBER) was positive. Herein, we discuss the clinicopathological features of this case and review the literature on primary extranodal NK/T-cell lymphoma of the lung. Compared with other patients, who died after the first cycle of chemotherapy and/or within three months, our patient had longer survival under aggressive chemotherapy and auto-peripheral blood stem cell transplantation.

EBV-associated Burkitt lymphoma in Taiwan is not age-related.

This study retrospectively investigated 54 cases of sporadic Burkitt lymphoma in Taiwan with histopathology review, immunohistochemistry, Epstein-Barr virus (EBV) in situ hybridization (EBER) and fluorescence in situ hybridization (FISH). The great majority revealed typical immunophenotype and 89% (47/53) cases expressed myc protein. EBER was positive in 20% (11/54) of cases, more frequently with nodal presentation, but not significantly associated with age (pediatric vs. adult), abdominal vs. extra-abdominal presentation or overall survival (OS). MYC and IGH were rearranged in 94% (46/49) and 85% (41/48) of cases, respectively. The concordance rate between myc expression and MYC translocation was 83% (40/48). By univariate analysis, OS was statistically associated with age, with or without chemotherapy, central nervous system (CNS) involvement, CNS prophylaxis and leukemic transformation, but not gender, nodal vs. extranodal involvement, stage, immunohistochemistry, EBER, myc expression, MYC translocation or radiotherapy. By multivariate analysis, CNS involvement at presentation and administration of chemotherapy were statistically associated with OS.

Primary Intestinal Diffuse Large B-cell Lymphoma in Taiwan Showed a Relative Higher Rate of Perforation and EBV Association.

We retrospectively investigated 59 surgically resected primary intestinal diffuse large B-cell lymphomas (PI-DLBCL) including 31 males and 28 females with a median age of 66. Eleven (19%) tumors were perforated at presentation; 8 (14%) were multicentric. Ileum (n=24; 43%) and ileocecum (n=17; 30%) were most frequently involved. Twenty-one (36%) patients did not receive chemotherapy or radiotherapy including 6 with perforation and died in 0.2 to 7 months. The 1-, 2-, and 5-year overall survival rates were 68.4%, 56.5%, and 50.0%, respectively. Seven (12%) of 59 cases were positive for Epstein-Barr virus (EBV) by in situ hybridization. IGH, BCL2, BCL6, and MYC foci were rearranged in 22%, 3%, 17%, and 7% cases, respectively, with 14% exhibiting gain/amplification at the MYC locus. Perforation (P=0.009), high ECOG PS (≥2) (P=0.018), and no adjuvant chemotherapy (P<0.001) were poor prognostic factors but not immunophenotype including co-expression of bcl-2 and myc, EBV status, or chromosomal aberrations. Perforation and chemotherapy remained significant by multivariate analysis. PI-DLBCL in Taiwan carried a relatively higher rate of perforation, lower frequency of germinal center B-cell phenotype, and higher EBV association as compared with studies from other geographic areas. Furthermore, perforation was a poor prognostic factor.

Extranodal natural killer/T-cell lymphoma, nasal type in Taiwan: a relatively higher frequency of T-cell lineage and poor survival for extranasal tumors.

Extranodal natural killer (NK)/T-cell lymphoma, nasal type, is a predominantly extranodal lymphoma associated with Epstein-Barr virus occurring most frequently in the upper aerodigestive tract. There are limited reports on cellular origin and prognostic factors. We retrospectively investigated 73 cases with a median age of 54 years and a male-female ratio of 2.0:1. The upper aerodigestive tract (nasal group) was the most common site of involvement (51 cases; 70%). The other organs (n = 22; extranasal group) included the skin (12 cases; 16%) and gastrointestinal tract (5; 7%). Of the 70 cases with complete staging, 71% had stage I/II disease. All cases were positive for Epstein-Barr virus by in situ hybridization. Using immunohistochemistry and clonality assay for T-cell receptor gene rearrangement, these tumors were classified into NK (n = 39; 53%), T (n = 13; 18%), and indeterminate lineage (n = 21; 29%). The only clinicopathological difference among these 3 groups was rare CD5 expression in the NK-cell group. Nasal tumors were more frequently of NK-cell origin, and extranasal tumors were equally of either T- or NK-cell origin. The 5-year overall survival rate was 35.6%. The overall survival time was shorter in the extranasal group, although there was no statistical difference in age, sex, and histologic or immunophenotypic features between the 2 groups. Excluding the cases with indeterminate lineage, 75% of cases were of NK lineage; and 25%, T lineage. Extranasal tumors were more aggressive than their nasal counterparts. A prospective national study is warranted for a better understanding of the clinicopathological and genetic features of this uncommon tumor and the prognostic factors.

Primary cutaneous NK/T-cell lymphoma, nasal type and CD56-positive peripheral T-cell lymphoma: a cellular lineage and clinicopathologic study of 60 patients from Asia.

Primary cutaneous, extranodal natural killer/T-cell lymphoma, nasal type (PC-ENKTL), is a rare Epstein-Barr virus (EBV)-associated neoplasm with poorly defined clinicopathologic features. We performed a multinational retrospective study of PC-ENKTL and CD56-positive EBV-negative peripheral T-cell lymphoma (PC-CD56+PTCL) in Asia in an attempt to elucidate their clinicopathologic features. Using immunohistochemistry for T-cell receptors (TCRs), in situ hybridization for EBV, and TCR gene rearrangement, we classified 60 tumors into 51 with PC-ENKTL (20 of NK-cell, 17 T-cell, and 14 indeterminate lineages) and 9 with PC-CD56+PTCL. Tumors of T-cell origin accounted for 46% of PC-ENKTLs with half of these cases being TCR-silent. As compared with T-lineage tumors, PC-ENKTLs of NK-cell lineage had more frequent involvement of regional lymph nodes and more frequently CD8-negative and CD56-positive. Cases of PC-ENKTL showed more frequent tumor necrosis, younger age, and a higher frequency of CD16 and CD30 expression than cases of PC-CD56+PTCL. CD56-positive T-lineage PC-ENKTL tumors (n=8) had more localized disease in the TNM (tumor-node-metastasis) staging and were more often of γδ T-cell origin compared with cases of PC-CD56+PTCL (n=9). PC-ENKTLs and PC-CD56+PTCLs were equally aggressive, with a 5-year overall survival rate of 25%. Tumor necrosis and CD16 expression may serve as useful surrogates for differentiating PC-ENKTL from PC-CD56+PTCL. A single lesion, an elevated lactate dehydrogenase level, and the presence of B symptoms were independent poor prognostic factors for PC-ENKTL in multivariate analysis. Further studies with more cases are warranted to delineate the clinicopathologic features and significance of EBV in these rare lymphomas.

Ciliated muconodular papillary tumor of the lung: a newly defined peripheral pulmonary tumor with conspicuous mucin pool mimicking colloid adenocarcinoma: a case report and review of literature.

We report the case of a 68-year-old man with a newly defined rare entity of a peripheral pulmonary tumor, consisting of a nodular papillary lesion with papillary structures containing ciliated columnar and goblet cells, as well as floating tumor cells in the mucin pool. The conspicuous mucin pool was observed to be mimicking colloid adenocarcinoma in a low-power view, particularly in a frozen section slide. We originally reported it as an adenocarcinoma during intraoperative consultation. Immunohistochemically, the tumor cells exhibited a similar immunophenotype to pulmonary adenocarcinoma, except for the presence of focal ciliated and basaloid cells, which we found using CK5/6 and P63 immunostaining. No KRAS or EGFR mutation was found. We revised the diagnosis to that of a ciliated muconodular papillary tumor (CMPT). Four years after a wedge resection, the patient remained free of tumors. Although the malignant potential of CMPT cannot be ignored, a wedge resection with a safe margin might be a treatment option for CMPT patients.

Cutaneous EBV-positive γδ T-cell lymphoma vs. extranodal NK/T-cell lymphoma: a case report and literature review.

Primary cutaneous γδ T-cell lymphoma and extranodal natural killer (NK)/T-cell lymphoma (ENKTL), nasal type are two distinct lymphoma entities in the World Health Organization (WHO) classification. We report the case of an aggressive cutaneous lymphoma of γδ T-cell origin showing overlapping features of both lymphomas. A 78-year-old female presented with confluent erythematous plaques with ulcerations over her right thigh. Microscopically, section of the skin showed a diffuse dermal and subcutaneous lymphocytic infiltration with tumor necrosis and angioinvasion. The medium- to large-sized tumor cells expressed CD3, CD8, cytotoxic molecules and T-cell receptor (TCR)-γ but not CD4, CD20, CD30, CD56 or ßF1. In situ hybridization for Epstein-Barr virus-encoded mRNA (EBER) was diffusely positive. Polymerase chain reaction-based clonality assay showed a clonal TCR-γ chain gene rearrangement. The features compatible with γδ T-cell lymphoma include dermal and subcutaneous involvements, cytotoxic phenotype, expression of TCR-γ, as well as an aggressive course. On the other hand, the diffuse EBER positivity, angioinvasion, tumor necrosis and cytotoxic phenotype may also fit in the diagnosis of an ENKTL of T-cell lineage. We review the literature on EBER-positive γδ T-cell lymphoma and discuss the diagnostic dilemma using the current WHO classification system.

Uterine lipoleiomyosarcoma: report of 2 cases and review of the literature.

Uterine lipoleiomyosarcoma is a rare entity with only 6 case reports in the Pubmed database at the time of writing this article. We report 2 additional cases of uterine lipoleiomyosarcoma, characterized on microscopy by coexistence of leiomyosarcomatous and liposarcomatous components, with focal intermingling, without an intervening lipoleiomyomatous area. The liposarcomatous component in both of our cases had the morphology of myxoid liposarcoma. Both cases underwent postoperative chemotherapy. One of our cases had recurrence in the pelvis with microscopic features of myxoid liposarcoma. This patient died with multiple metastases 4.5 yr after hysterectomy, with the metastatic lesions being liposarcomas, without an evident leiomyosarcomatous component. Although lacking a treatment protocol because of the rarity of such cases, postoperative adjuvant therapy is mandatory.

Diagnostic pitfalls of nonsecretory myeloma manifesting as multiple foci of periosseous plasmacytomas.

Nonsecretory myeloma, which comprises 1-5% of all myelomas, is a variant of plasma cell myeloma. It is defined as symptomatic myeloma without detectable monoclonal immunoglobulin levels on serum or urine immunofixation electrophoresis. Here, we report two cases of nonsecretory plasma cell myeloma that manifested as multi-foci periosseous plasmacytomas. Due to the inability to detect monoclonal immunoglobulin on serum or urine immunofixation electrophoresis and the lack of evidence of clonal plasma cells in the bone marrow, it was difficult to establish an early, accurate diagnosis. Misdiagnosing or mislabeling symptomatic myeloma patients with plasmacytoma results in the delay of their systemic treatment. Therefore, comprehensive imaging studies, the detection of free light chains, and histopathological confirmation from different sites and time points are necessary.

Primary appendiceal precursor B lymphoblastic lymphoma with peculiar morphology mimicking diffuse large B cell lymphoma.

Precursor B lymphoblastic neoplasm usually presented as childhood leukemia. Most precursor lymphoblastic lymphoma are T-cell lineage and precursor B lymphoblastic lymphoma constitutes only about 10% of cases according to the WHO Classification of Tumours of Haematologic and Lymphoid Tissues. The most frequent sites of involvement in precursor B lymphoblastic lymphoma are the skin, soft tissue, bone and lymph nodes. Primary appendiceal involvement is an uncommon condition. We present an unusual case of primary appendiceal precursor B lymphoblastic lymphoma in an 11-year-old boy with peculiar histological morphology mimicking diffuse large B cell lymphoma. Histologically, the tumor was composed of diffusely infiltrated large cells from mucosa and extended to the subserosal area. The tumor cells were positive to CD79a, CD20, PAX5, BCL2, CD10, TdT, p53 but not to CD3, BCL6 and CD34 by immunohistochemical studies. The response to conventional treatment regimen for lymphoblastic lymphoma was not good, with early relapse within three months. Partial remission was achieved by adding rituximab. Unfortunately, the patient died in ten months due to uncontrolled relapsed disease with generalized lymphadenopathy and massive pleural effusion. The special morphologic changes and poor response to chemotherapy may be related to the overexpression of p53.