Small Cell Lymphoma Research Articles

A possible case of Erdheim–Chester Disease

Aim: To present the case of a 57-year-old male with progressive bilateral proptosis. Material and method: The patient presented with bilateral proptosis and strength deficiency on the upper limbs. During hospitalization, the progression was unfavorable; proptosis progressed, causing a severe loss of vision in the left eye (from 0.8 Snellen to NLP). Results: The imagistic investigation revealed bilateral infiltration of the orbits, infiltrative lesions to the mediastinum and the abdomen. The patient was referred to neurosurgery for further management. Surgical orbital decompression was performed with biopsy. The histopathological examination revealed non-Hodgkin small cell lymphoma. Conclusions: Assembling the clinical and paraclinical data we have suspected the possible diagnosis of Erdheim-Chester disease, however, positive diagnosis has not been achieved.

Overview of idelalisib for pharmacists

AbstractIdelalisib is a potent oral selective inhibitor of phosphatidylinositol 3‐kinase p110δ. It is approved in Australia for the treatment of relapsed chronic lymphocytic leukaemia and small cell lymphocytic lymphoma in combination with rituximab or ofatumumab in patients for whom chemoimmunotherapy is not considered suitable. Idelalisib is reimbursed by the Australian Government for use in combination with rituximab. It is also approved and reimbursed for use as monotherapy in patients with follicular lymphoma refractory to at least two prior systemic therapies including rituximab and an alkylating agent. Idelalisib has demonstrated significant benefits in progression‐free survival and overall survival in these patient populations; however, patients receiving idelalisib require monitoring and education due to significant toxicities, particularly diarrhoea, infections and hepatotoxicity. There is also the potential for drug interactions resulting in toxicity or subtherapeutic treatment levels.

Splenic B-Cell Lymphoma/Leukemia, Unclassifiable in Japan

IntroductionSplenic B-cell lymphoma/leukemia, unclassifiable is defined as being unable to be classified as any other B-cell neoplasm infiltrating the spleen (World Health Organization Classification of Tumors of Haematopoietic and Lymphoid Tissue 2017). In splenic B-cell lymphoma/leukemia, unclassifiable, splenic diffuse red pulp small cell lymphoma (SDRPL) and hairy cell leukemia variant (HCL-v) are provisionally defined. The incidence of these diseases is rare. It has been reported that they account for 9% of splenic B-cell lymphomas (Haematologica 2010;95:1122-1129). There are no reports of histopathological examinations or BRAF mutations (V600E) in Japan. It has been shown that BRAF mutations (V600E) are found in all patients with Hairy cell leukemia-classical (HCL-c) (N Engl J Med. 2011 364: 2305-2315). This study aimed to clarify the pathological features of splenic B-cell lymphoma/leukemia, unclassifiable.MethodsWe analyzed 5 cases of suspected splenic B-cell lymphoma/leukemia, unclassifiable in terms of splenectomy. Five cases include 0 cases of SDRPL, 2 cases of HCL-v, and 3 cases of splenic B-cell lymphoma/leukemia, unclassifiable not applicable to either case. We analyzed patients undergoing splenectomy who were pathologically diagnosed at the Kurume University Pathology Course between July 2012 and May 2017. Splenic B-cell lymphoma/leukemia, unclassifiable was suspected in 5 cases. From the findings of peripheral blood, bone marrow, and BRAF mutation (V600E) analyses, 2 patients were diagnosed with HCL-v. The other 3 patients were diagnosed with splenic B-cell lymphoma/leukemia, unclassifiable. Pathological examinations were performed in these cases.Marker expression analysis of the B-cell line was performed using immunohistochemical (IHC) staining and flow cytometry (FCM). IHC staining was performed on formalin-fixed paraffin-embedded samples. For FCM analysis, we confirmed the clonality of B cells and analyzed their expression. A positive judgment was made at 30% or greater. For BRAF mutation (V600E) analysis, deoxyribonucleic acid was extracted from formalin-fixed paraffin-embedded samples and performed using the Sanger sequencing method.ResultsThe results of the analysis are shown in Table 1. HCL-v cases included 1 man and 1 woman, and the age was 62-71 years old. Splenic B-cell lymphoma/leukemia, unclassifiable cases included 2 men and 1 woman, and the age was 56-66 years. Splenic B-cell lymphoma/leukemia, unclassifiable cases involved bone marrow infiltration of B-cell lymphoma in 2 cases. In 3 cases of splenic B-cell lymphoma/leukemia, unclassifiable, there were no cases in which hairy cells were recognized in the peripheral blood. In all cases of splenic B-cell lymphoma/leukemia, unclassifiable, BRAF mutations (V600E) were not observed.All cases of splenic B-cell lymphoma/leukemia, unclassifiable and HCL-v tested positive for cluster of differentiation (CD)20, CD19, and B-cell lymphoma (Bcl-2) and tested negative for CD103 and CD10. All HCL-v cases and 2 of 3 cases of splenic B-cell lymphoma/leukemia, unclassifiable tested positive for cyclin D3. One case of splenic B-cell lymphoma/leukemia, unclassifiable tested positive for CD5, but negative for lymphoid enhancer-binding factor 1 (LEF1), cyclin D1, and Sox11. All other cases tested negative for CD5, LEF1, cyclin D1, and Sox11. One of two cases of HCL-v and 2 of 3 cases of splenic B-cell lymphoma/leukemia, unclassifiable tested positive for CD11c. All HCL-v cases tested negative and 1 of 3 cases of splenic B-cell lymphoma/leukemia, unclassifiable tested positive for Bcl-6. IHC staining was performed because FCM was not performed in 1 case of HCL-v. There was no obvious bias in κ and λ. One patient with HCL-v who underwent FCM was κ-positive. Splenic B-cell lymphoma/leukemia, unclassifiable was κ-positive in all cases.ConclusionsIn this analysis, splenic B-cell lymphoma/leukemia, unclassifiable did not involve BRAF mutations (V600E) in all cases. It has been reported that cyclin D3 is highly expressed in SDRPL. Splenic B-cell lymphoma/leukemia, unclassifiable and HCL-v confirmed the same tendency (Blood. 2017; 129:1042-1045). Further molecular biological analysis for splenic B-cell lymphoma/leukemia, unclassifiable is desired. DisclosuresNo relevant conflicts of interest to declare.

Immunohistochemical Profiling of Canine Intestinal T-Cell Lymphomas.

Human enteropathy-associated T-cell lymphoma (EATL) is classified into 2 distinct subgroups based on their phenotypes (type I and type II). Canine intestinal T-cell lymphoma can be morphologically classified into large and small cell lymphomas (LCL and SCL, respectively). Their association with human EATL or immunohistochemical and biological features has not been well characterized. In this study, the immunohistochemical profiles of 17 cases of LCL and 33 cases of SCL were evaluated with markers used for human EATL classification. Morphologically, LCL was characterized by sheet-like proliferation of large to moderately sized neoplastic lymphocytes, with scant clear cytoplasm and pleomorphic, irregularly shaped nuclei containing distinctive nucleoli and scattered chromatin. In contrast, SCL was characterized by the proliferation of monomorphic small neoplastic lymphocytes, accompanied by infiltration of nonneoplastic plasma cells. Interestingly, 8 cases demonstrated mixed LCL and SCL morphologies. Granular cytoplasmic expression of granzyme B was observed in most LCL and SCL cases. Membranous expression of CD56 was demonstrated in only 2 of 17 LCL and 0 of 33 SCL cases. Coexpression of CD20 by neoplastic T cells was observed in more SCL cases (16/33; 48%) than LCL cases (1/17; 6%). The CD56-positive cells in 2 cases were negative for CD20. Although canine LCL shares common features with human EATL type I, canine SCL cells and human EATL type II differ in their immunophenotype. Canine intestinal T-cell lymphoma had a homogeneous immunophenotype regardless of cell morphology. The findings of this study may indicate large cell transformation of SCL rather than 2 distinct entities.

Histo-morphologic Spectrum of Non-Hodgkin Lymphoma According to WHO Classification 2016: A Cross-Sectional Study

Background: Geographic variations with regard to incidence and histological subtypes are known to occur in Non-Hodgkin lymphoma (NHL). This study was aimed to see the incidence and subtypes of NHL in a group of Bangladeshi population.Methods: This cross sectional study was carried out in Armed Forces Institute of Pathology (AFIP) Bangladesh, from 1st April 2017 to 31st March 2018. All nodal and extranodal tissues which were morphologically diagnosed as NHL were included in the study and immunohistochemistry was done for sub-classification according to WHO classification 2016. Bone marrow trephine biopsy samples were excluded.Results: Total cases: 106, mean age: 48.5 years ± 18.5 (range 2Y 9 M –82 years), male-female ratio: 2.2:1. Total subject of B cell Lymphoma (BNHL): 83 (78.3%) and T cell lymphoma (TNHL): 23 (21.7%). Among BNHL, total subjects of diffuse large B cell lymphoma (DLBCL) 50 (60%), follicular lymphoma 9 (11%), marginal zone lymphoma 8 (10%), small cell lymphoma and mantle cell lymphoma 5 (6%) each, Burkitt lymphoma 4 (5%) and B cell lymphoblastic lymphoma 2 (1.89%) in number. Among TNHL peripheral T-cell lymphoma NOS 11 (48%), anaplastic large cell lymphoma (ALCL) 5 (22%), T cell lymphoblastic lymphoma 4 (17%), and angio-immunoblastic T cell lymphoma 3 (13%) in number. Among 5 ALCL, 4 ALK positive and 1 ALK negative. Number of primary extra-nodal NHL were 29 (27%) with most common involved organ system being GIT and most common histological subtype being DLBCL.Conclusion: Quite similar pattern of age range with mean age, male to female ratio, subtypes and extra nodal NHL distribution prevailing in our subcontinent is found in our population with subtle increased incidence of TNHL indicating the necessity of further large epidemiological study.Birdem Med J 2018; 8(3): 215-222

Etoposide – inhalable fraction. Determination method in workplace air

Etoposide at room temperature is a fine white to yellow-brown crystalline odorless powder. Etoposide is one of the most widely used cytotoxic drugs and has strong antitumour activity in cases of small-cell lung cancer, testicular cancer or lymphoma. Occupational exposure to etoposide (mainly via skin contact or via inhalation route) may occur among group of healthcare workers or workers employed in the production of this drug. Exposure to etoposide can cause suppression of bone marrow function and gastrointestinal symptoms such as nausea, vomiting, bronchospasm, inflammation of mucous membranes, hair loss and secondary leukemia. Agency for Research on Cancer (IARC) has classified etoposide as a compound probably carcinogenic to humans (Group 2.A) and in combination with cisplatin and bleomycin as carcinogenic to humans (Group 1). The aim of this study was to develop and validate a sensitive method for determining inhalable fraction of etoposide concentrations in workplace air in the range from 1/10 to 2 MAC values, in accordance with the requirements of Standard PN-EN 482. The study was performed using a liquid chromatograph with tandem mass detection (HPLC-MS/MS). All chromatographic analysis were perfomed with Supelcosil LC 18 150 × 3 mm analytical column, which was eluted with a mixture of methanol and water with 0.1% of formic acid. This method is based on collecting inhalable fraction of etoposide on glass fiber filter, extracting with a mixture of methanol: water with addition of formic acid (0.1%), and chromatographic determining of resulted solution with HPLC-MS/MS technique. The average extraction efficiency of etoposide from filters was 90%. The method is linear (r = 0.9985) within the investigated working range from 0.036 μg/ml to 1.44 μg/ml. The calculated limit of detection (LOD) and the limit of quantification (LOQ) were 0.0086 and 0.0026 μg/ml, respectively. The analytical method described in this paper, thanks to HPLC MS/MS technique, enables specific and selective determination of inhalable fraction of etoposide in workplace air in the presence of other compounds at concentrations from 0.0001 mg/m3 (1/20 proposed MAC value). The method is precise, accurate and it meets the criteria for measuring chemical agents listed in Standard No. EN 482. The method can be used for assessing occupational exposure to etoposide and associated risk to workers’ health. The developed method of determining etoposide has been recorded as an analytical procedure (see appendix).

Feline large-cell lymphoma following previous treatment for small-cell gastrointestinal lymphoma: incidence, clinical signs, clinicopathologic data, treatment of a secondary malignancy, response and survival.

Lymphoma is a common and clinically important malignancy in cats. Development of a second malignancy has been reported previously in 7-14% of cats with small-cell gastrointestinal (GI) lymphoma. The aim of our study was to describe the incidence, clinical signs, clinicopathologic data, response to therapy and outcomes in cats diagnosed with large-cell lymphoma following treatment for small-cell GI lymphoma. Medical records from a single referral specialty hospital were reviewed for all cats with lymphoma diagnosed between 2008 and 2017. The cases with a diagnosis of small-cell GI lymphoma followed by a diagnosis of any large-cell lymphoma and complete outcome data were selected for further review. Seven hundred and forty cats with a diagnosis of lymphoma were identified. Twelve cats (12/121) treated for small-cell GI lymphoma followed by a diagnosis of any anatomic form of large cell lymphoma were identified. Nine cats met the study inclusion criteria and were used in analyses. Mean event-free survival time from small-cell GI lymphoma diagnosis until diagnosis of large-cell lymphoma was 543 days, with a median survival time of 615 days. Mean event-free survival time from large-cell lymphoma to death was 55 days, with a median survival time of 24.5 days. Hematocrit, albumin and total protein were significantly decreased when cats developed large-cell lymphoma compared with their values at the time of small-cell lymphoma diagnosis. Large-cell lymphoma occurred in 9.9% (12/121) of cats treated for small-cell GI lymphoma. Feline practitioners should include large-cell lymphoma on their list of differential diagnoses in cats diagnosed with small-cell GI lymphoma developing weight loss, anemia, hypoalbuminemia and hypoproteinemia.

Pathological features of intestinal T-cell lymphoma in Shiba dogs in Japan.

Intestinal T-cell lymphoma is being more frequently diagnosed in dogs owing to the wide availability of endoscopy and clonality analysis in veterinary medicine. However, no epidemiological study on intestinal T-cell lymphoma has been previously performed, and hence, information about dog breed, age and sex distributions of intestinal T-cell lymphoma has largely remained unclear. In this study, breed predisposition to canine intestinal T-cell lymphoma was determined by calculating odds ratios and 95% confidential intervals. Of the 43 breeds identified, 7 appeared to have an increased risk of developing intestinal T-cell lymphoma, including Shiba dogs, German shepherds, Cairn terriers, Boston terriers, Papillons, Pugs and Maltese. Immunohistochemistry of representative Shiba cases revealed ubiquitous cytotoxic immunophenotype in both large and small cell lymphomas. Interestingly, CD20 co-expression was observed in 11% of cases. It could potentially be aberrant expression of CD20 or neoplastic transformation of a normal subset of CD20-positive T-cells. A comparison of mean age between representative breeds revealed that Shiba dogs were slightly younger than Miniature Dachshunds (P < .05). However, there was no difference in survival between the 2 breeds. As Shiba dogs are predisposed to chronic enteropathy, there may be underlying inflammatory process contributing to lymphomagenesis of intestinal T-cell lymphoma in this breed. Our findings provide insights into the underlying pathogenesis of breed-specific canine intestinal T-cell lymphoma.

Unilateral localized conjunctival amyloidosis in a patient with a history of contralateral orbit/eyelid lymphoma

Amyloidosis is a disorder characterized by the deposition of insoluble abnormal proteins in the extracellular space. It may occur as a localized lesion or as a systemic disease involving multiple organs and systems. Localized conjunctival amyloidosis is rare and is less frequently associated with systemic involvement. Although amyloidosis itself is a benign lesion involvement of multiple organs and systems is associated with poor prognosis. Diagnosis of amyloidosis is made on biopsy specimens with Congo red staining for the appearance of apple-green birefringence under polarized light microscopy. Liquid chromatography tandem-mass spectrometry (LC-MS/MS) is much more sensitive in diagnosing amyloidosis and can determine the type of amyloid deposit. Here we reported a case of conjunctival amyloidosis in a 52 year-old male patient who was presented with left lower eyelid swelling to our medical center. He has a complicated past medical history of anti-phospholipid antibody syndrome, Buerger's disease (thromboangitis obliterans), and small cell lymphoma (SLL) of the right orbit/eyelid. The patient received radiation to the right orbit to treat SLL with therapy completed one and a half years prior to presentation. Physical examination revealed a firm, raised yellowish colored lesion in the left lower conjunctiva. The conjunctival lesion was biopsied, and tissue sections were examined with Congo red stains and LC-MS/MS analysis. The biopsy showed amyloid deposits without evidence of malignancy, and the type of proteins in the deposit was immunoglobulin light chain (AL) of kappa type. A complete work up was taken for possible systemic involvement of amyloidosis and results were all negative. To our knowledge, this is the first case of localized conjunctival amyloidosis with a history of contralateral orbit/eyelid SLL.

CD5 positive follicular lymphomas: A diagnostic dilemma in a resource restricted laboratory setting

Background: Follicular lymphoma is an indolent B Non Hodgkin lymphoma which has a characteristic follicular growth pattern and immunohistochemical expression. The neoplastic cells express CD20, CD10, BCL2 and are negative for CD5, CD23 and Cyclin D1. CD5 is a useful marker in the differentiation of various B cell lymphomas. Small cell lymphoma and mantle cell lymphoma express CD5. Some of the follicular lymphomas express CD5 which results in diagnostic confusion. Methods: 52 cases of lymphoma were diagnosed over a period of 2 years in a tertiary care centre in south India. Among these, 9 cases were diagnosed as follicular lymphoma based on the morphological abd immunohistochemical study. A panel of antibodies were chosen based on the morphological diagnosis.The panel used for small cell lymphomas include CD20, CD3, CD5 CD23, Cyclin D1, CD10, BCL2 and Ki67. Result: Of the nine cases of follicular lymphoma, three were CD5 positive. Two showed bone marrow involvement. There was no significant morphological difference between CD5 positive and CD5 negative follicular lymphoma. Conclusion: The expression of CD5 by follicular lymphomas could be problematic when the follicular lymphoma as such lacks its characteristic follicular pattern and there are no molecular studies available. Eventhough rare , follicular lymphoma is to be considered in the differential diagnosis of CD5 positive follicular lymphomas. DOI: 10.21276/APALM.1364

Merkel Cell Carcinoma Metastatic to Pleural Fluid: A Case Report.

Merkel cell carcinoma (MCC) is a rare aggressive neuroendocrine carcinoma of the skin that shows locoregional or distant metastasis. Metastasis of MCC to body cavity effusion is extremely rare; only three cases have been reported so far. Metastatic MCC in effusion cytology shows small blue round cells with fine stippled chromatin like other small blue round cell tumors such as small cell lung carcinoma or lymphoma. The diagnosis of metastatic MCC can grant patients good chances at recently advanced therapeutic options. Here, we present a case of metastatic MCC to pleural effusion with characteristic single file-like pattern.

Differences between chronic lymphocytic leukaemia and small lymphocytic lymphoma cells by proteomic profiling and SNP microarray analysis

The majority of malignant cells in chronic lymphocytic leukaemia (CLL) circulate in the peripheral blood whereas small lymphocytic lymphoma (SLL) cells reside in tissues. The aim of this study was to detect differences in chemokine receptor expression, DNA single nucleotide polymorphism (SNP) microarray analysis and proteomic profiling to help elucidate why the cells remain in their respective environments. We identified by flow cytometric studies of chemokine receptors and DNA SNP microarray analysis significant differences between cells from CLL and SLL patients. Proteomic analysis revealed two potential markers (m/z 3091 and 8707) to distinguish the two disorders. There was a significantly greater expression of leucocyte trafficking receptor CXCR3 (CD183) and migration and homing receptor CXCR4 (CD184), and significantly lower expression of cell adhesion molecule integrin α4 chain (CD49d), on CLL cells, compared with SLL cells. Conversely, SNP microarrays revealed greater numbers of copy-neutral loss of heterozygosity chromosomal aberrations, as well as gross chromosomal aberrations, in the SLL group, compared with the CLL group. These findings revealed that there was a significantly greater expression of trafficking, migration and homing receptors and significantly lower expression of adhesion molecules on CLL cells than on SLL cells, and that SLL may be a more progressive disease than CLL, with a more complex genotype.

Endoscopic Cytology for the Diagnosis of Chronic Enteritis and Intestinal Lymphoma in Dogs.

Although cytology is a rapid diagnostic procedure in dogs, the cytologic criteria of endoscopic biopsies for chronic enteritis and intestinal lymphoma are not well defined. An immediate diagnosis using cytology would benefit patients by enabling prompt initiation of therapy. The objective of this study was to investigate the correlation between the results of endoscopic cytology and histopathology. In this study, 167 dogs with clinical signs of chronic gastrointestinal disease were included. On the basis of histopathology, the following diagnoses were determined: lymphocytic-plasmacytic enteritis in 93 dogs; eosinophilic enteritis in 5 dogs; small cell intestinal lymphoma in 45 dogs; and large cell intestinal lymphoma in 24 dogs. Two clinical pathologists retrospectively evaluated the endoscopic cytology of squash-smear preparations. The cytologic diagnoses of inflammation, small cell lymphoma, and large cell lymphoma were based on the severity of lymphocyte infiltration, the size of infiltrated lymphocytes, and eosinophil/mast cell infiltration. The clinical severity score was significantly increased along with the degree of lymphocyte infiltration evaluated by cytology. The cytologic diagnosis was in complete agreement with the histopathologic diagnosis in 136 of 167 (81.4%) cases. For the differentiation between enteritis and lymphoma, endoscopic cytology had a sensitivity of 98.6%, a specificity of 73.5%, a positive predictive value of 72.3%, and a negative predictive value of 98.6%. The log-rank test and Cox regression analysis showed that the results of cytology predicted the prognosis. These results suggest that endoscopic cytology is a useful technique to aid diagnosis of intestinal inflammation and lymphoma in dogs.

Characteristics of orbital lymphoma: a clinicopathological study of 26 cases.

Evaluation of the medical data of patients with orbital and adnexal lymphoma. Cohort study of all cases diagnosed with orbital or adnexal lymphoma at Meir Medical Center between 1993 and 2007. Twenty-six patients, with intraorbital or subconjunctival masses with orbital involvement, were examined and followed up between 1 and 8years. Examined data included: clinical presentation, age, gender, imaging, tumor location, surgical management, and pathological diagnosis. Presenting signs and symptoms included proptosis, eyelid lesions, tearing, chemosis, decreased visual acuity, ptosis, pain, squint, and optic nerve compression. In five cases, lymphoma was misdiagnosed on neuroimaging. Bone changes were seen in four patients. All cases were B cell lymphomas; with the majority (22 cases) of small B cell type; consisting of primary extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue and two cases of small cell lymphoma. One small cell lymphomas was of follicular type on a background of CLL, and the other was CLL/SLL type. Fourteen cases were primary orbital disease, and 12 cases were systemic disease. Macroscopic appearance of lymphoma at open biopsy was characteristic in most cases. Flow cytometry phenotyping gave rapid reliable diagnosis of the disease. Epiphora or chemosis in the presence of an orbital mass should alert the ophthalmologist to suspect lymphoma. Lymphoma may be easily misinterpreted on neuroimaging for other diseases. Bone changes seen on CT are more common than is generally perceived. Macroscopic appearance at open biopsy was characteristic.

Clinical, laboratory, and morphological characteristics of kidney damage in lymphoproliferative disorders

Kidney involvement in the onset of lymphoproliferative diseases (LPD) detected rarely, observed mainly at tumor progression or relapse. Objective : to determine the clinical and morphological features of kidney damage in the initial manifestation of LPD. Materials and methods : 19 patients with LPD and kidney damage were included in the study. The diagnosis of non-Hodgkin’s lymphomas was established according to 2008 WHO classification. Histological and immunohistochemical, immunofluorescent and electron microscopic studies of nephrobiopsy have been performed. Results . Patients were aged 46-83 years (median 63 years), of which 13 were men and 6 women. Chronic lymphocytic leukemia / small cell lymphocytic lymphoma was established in 12 patients, marginal zone lymphoma – in 4 pts, follicular lymphoma – in 1 patient, Waldenstrom's macroglobulinemia – in 1 patient and diffuse large B-cell lymphoma (DLBCL) in 1 patient. Proteinuria was observed in 18 patients, microhematuria – in 6 pts, arterial hypertension – in 8 pts, nephrotic syndrome – in 3 pts and renal failure in 18 patients. The mean creatinine level was 330.9 ± 52.3 µmol/L, the average glomerular filtration rate was 25.7 ± 12.9 ml/min. Monoclonal IgMκ secretion was detected in 6 patients, BJκ protein – in 9 pts, increased free light chain level – in 4 pts, cryoglobulin – in 4 pts (type II cryoglobulin in 3 of them, type I – in 1 patient). Morphological study of nephrobiopsy revealed tumor lymphoid infiltration of kidney interstitium in 10 (52.6 %) cases. Diffuse small cell lymphoid proliferation was detected in 1 patient, local infiltration – in 9 pts, in 3 of them in combination with glomerulonephritis, and in 4 cases with kidney carcinoma. Local large cell lymphoid proliferation was found in 1 patient with DLBCL. Amyloidosis was detected in 2 pts and thrombotic microangiopathy – in 2 patients. Glomerulopathy was revealed in 10 patients (52.6 %): mesangioproliferative glomerulonephritis (MPGN) – in 4, mesangiocapillary glomerulonephritis – in 3, fibrillar glomerulonephritis (FGN) – in 1, immunotactoid glomerulonephritis – in 1, and glomerulonephritis with minimal changes – in 1 patient. Conclusion . Kidney damage in the onset of lymphatic tumor does not always manifest with proteinuria, hematuria, nephrotic syndrome and renal failure. In most cases, secretion of BJ protein, free light chains, monoclonal immunoglobulin and cryoglobulin are detected. Morphological changes are heterogeneous, including lymphoid proliferation, various types of glomerulopathies, amyloidosis and thrombotic microangiopathy.

Characterization of a PCR-based lymphocyte clonality assay as a complementary tool for the diagnosis of feline lymphoma.

Differentiation between resident mature lymphocyte populations and small cell lymphoma cannot be made by cytological review alone and remains challenging in histopathological review. These cases warrant application of complementary tools like PCR-based immunoglobulin (IG) and T-cell receptor (TCR) clonality testing for confirmation. In this prospective study, diagnostic sensitivity and specificity of different primer sets for routine diagnosis of feline TCR gamma (TCRG) and complete IG heavy chain (IGH) gene rearrangements were assessed. Fine needle aspirates from 20 feline lymphoma cases and lymph node material from 10 cats without hematopoietic neoplasia were subjected to clonality testing. Feline lymphoma cell lines and previously confirmed patient material served as positive control. Detection limits for clonal populations within a polyclonal background was 90% for B-cells and 50% for T-cells. Diagnostic sensitivity and specificity of the clonality assay were 70% and 90%. Overall diagnostic accuracy was 77%, positive predictive value 93% and negative predictive value 60%.

Lymphome primitif de la voûte crânienne : cas clinique et revue de la littérature

Primitive lymphomas of the bone are exceptional tumors, representing 4% of all non-Hodgkin lymphomas. The location at the skull remains the rarest. We report the case of a 56 year old patient with lytic lesions in the skull of a small cell lymphoma B, treated with primary chemotherapy and intensity-modulated radiotherapy in arctherapy with a dose of 30Gy in 15 fractions. With a follow-up time of 18 months after the end of treatment, the patient has no sign of disease evolution.

Identification of Mucosa-Invading and Intravascular Bacteria in Feline Small Intestinal Lymphoma

Persistent bacterial infections of the gastrointestinal mucosa are causally linked to gastric carcinoma and mucosa-associated lymphoid tissue (MALT) lymphoma in people and laboratory animals. We examined the relationship of mucosa-associated bacteria to alimentary lymphoma in cats. Intestinal biopsies from 50 cats with alimentary lymphoma (small cell, n = 33; large cell, n = 17) and 38 controls without lymphoma (normal to minimal change on histopathology, n = 18; lymphocytic-plasmacytic enteritis, n = 20) were evaluated. The number and spatial distribution of bacteria (ie, in luminal cellular debris, villus-associated mucus, adherent to epithelium, mucosal invasion, intravascular, or serosal) were determined by fluorescence in situ hybridization with the eubacterial probe EUB-338. Mucosa-invasive bacteria were more frequently observed in cats with large cell lymphoma (82%, P ≤ .001) than in cats with small cell lymphoma (18%), normal to minimal change on histopathology, and lymphocytic-plasmacytic enteritis (3%). Intravascular bacteria were observed solely in large cell lymphoma (29%), and serosal colonization was more common in cats with large cell lymphoma (57%) than with small cell lymphoma (11%, P ≤ .01), normal to minimal change (8%, P ≤ .01), and lymphocytic-plasmacytic enteritis (6%, P ≤ .001). The high frequency of invasive bacteria within blood vessels and serosa of cats with large cell lymphoma may account for the sepsis-related complications associated with large cell lymphoma and inform clinical management. Further studies are required to determine the role of intramucosal bacteria in the etiopathogenesis of feline alimentary lymphoma.

Differential expression of enhancer of zeste homolog 2 (EZH2) protein in small cell and aggressive B-cell non-Hodgkin lymphomas and differential regulation of EZH2 expression by p-ERK1/2 and MYC in aggressive B-cell lymphomas

AbstractEZH2, a member of the polycomb protein group, is an important methyltransferase that is overexpressed in various neoplasms. We found that in small cell B-cell lymphomas, EZH2 is expressed in <40% of neoplastic cells, with heterogenous signal intensity. In aggressive B-cell lymphomas, 70–100% of tumor cells were positive for EZH2 expression with high signal intensity, which correlated with a high proliferation rate. We investigated the potential signaling molecules that regulate EZH2 overexpression in aggressive B-cell lymphomas and found that 80% of cases of EZH2-positive diffuse large B-cell lymphoma show high p-ERK1/2 expression (average ~57% tumor cell positivity). In contrast, only a small percentage of tumor cells (~10%) show p-ERK1/2 expression in Burkitt lymphoma and double hit lymphoma. On average, 91 and 76% of neoplastic cells were positive for MYC expression in Burkitt lymphoma and double hit lymphoma, respectively, while only 20% neoplastic cells were positive for MYC expression in diffuse large B-cell lymphoma. None of the aggressive B-cell lymphomas showed significant p-STAT3 expression in EZH2-overexpressed cases. The correlation of EZH2 expression with aggressive behavior and proliferation rate in B-cell neoplasms suggests that this molecule may function as an oncogenic protein in these neoplasms, with possible regulation by different signaling cascades in different types of aggressive B-cell lymphomas: p-ERK-related signaling in diffuse large B-cell lymphoma, and MYC-related signaling in Burkitt lymphoma and double hit lymphoma. Furthermore, EZH2 and associated signaling cascades may serve as therapeutic targets for the treatment of aggressive B-cell lymphomas.

Characterization of the T-cell receptor gamma chain gene rearrangements as an adjunct tool in the diagnosis of T-cell lymphomas in the gastrointestinal tract of cats

Feline alimentary lymphoma is the most common hematopoietic neoplasia in cats. It affects mainly the small intestines and is most frequently of T-cell origin. Evaluation of a fine needle aspirate is often the first step in the diagnostic work-up. Differentiation between a resident mature lymphocyte population as encountered in inflammatory bowel disease and small cell lymphoma cannot be achieved by cytology alone. Even full thickness biopsies evaluated by histopathology can be inconclusive. These cases warrant the application of complementary tools like PCR-based T-cell receptor (TCR) clonality testing for confirmation.The aim of this study was to optimize the DNA extraction protocol for formalin fixed and paraffin embedded tissues (FFPE) and to establish a heteroduplex analysis to enhance resolution of the PCR fragments of the T-cell receptor gamma (TCRG) V-J gene. The new protocols resulted in improved quantity and quality of the extracted DNA. Heteroduplex analysis of the samples improved the resolution of the electrophoresis results so that rules for interpretation of the different patterns could be established. Application of this improved setup detected clonal rearrangements in at least one TCRG primer reaction in 31 of 36 of our feline intestinal lymphoma samples after DNA quality testing.