Multifocal in situ mantle cell neoplasia of the ileocecal region: a case report with simultaneous nodal and extranodal involvement.

In situ mantle cell neoplasia (ISMCN) is a rare entity of disputed clinical significance. We report an additional case, unusual by its presentation in the large intestine and its multifocal involvement of several nodal and extranodal sites. The diagnosis was made in a 46-year-old male patient from a surgical specimen resected for cecal adenocarcinoma. Gross examination showed multiple small polypoid lesions surrounding the ileocecal valve, corresponding to lymphoid aggregates with hyperplastic follicles. Numerous cyclin D1/SOX11+ lymphoid cells, harboring the t(11;14)(q13;q32) translocation, were present in the inner layers of mantle zones. The same lesions were found in the ileum, the appendix, and the regional lymph nodes. The final diagnosis was multifocal ISMCN of the ileocecal region, with both nodal and extra-nodal involvement. A simple surveillance was decided. Our observation expands the clinical spectrum of the disease and underlines the necessity to closely examine even normal-appearing reactive lymphoid tissues.

Improving precise counting of mitotic cells in mantle cell lymphoma using phosphohistone H3 (PHH3) antibody.

AIMS: Mantle cell lymphoma (MCL) has a highly heterogeneous clinical course ranging from indolent, to aggressive and rapidly progressive disease. Proliferation is a strong predictor for disease outcome. In routine clinical practice, Ki-67 expression is used as a measure of proliferation. However, several studies have documented a high degree of inter-laboratory and inter-observer variation with Ki-67 immunohistochemistry. Phosphorylation of histone H3 occurs specifically during mitosis and hence serves as a specific marker for cells in mitosis. METHODS AND RESULTS: We investigated phosphohistone H3 (PHH3) immunohistochemistry as a proliferation maker in 28 tissue biopsies of MCL and compared the PHH3 results (as evaluated by direct microscopic visualisation and image analysis-aided scoring) with morphological subtyping, mitotic counts and Ki-67 index. We found PHH3-mitotic count was about sixfold higher than H&E-mitotic count (mitoses in 10 high power fields). Furthermore, PHH3-mitotic count in aggressive morphological variants of MCL was significantly higher than in usual MCL. The PHH3-mitotic count showed a strong linear correlation with PHH3-mitotic index (percentage positive cells). CONCLUSIONS: We found PHH3 immunohistochemistry, a reliable mitosis-specific marker, in MCL. Performing precise counts and evaluating precise proliferation indices is easier with PHH3 immunohistochemistry. This contrasts with the conventional estimation of Ki-67 percentages by 'eye-balling'.

Orbital soft tissue composite lymphoma presenting as recurrence of a nodal lymphoma with mantle and follicular cell components: A case report, literature review and guideline for the treatment of patients.

Composite lymphoma with mantle and follicular cell components is a challenging diagnosis. Flow cytometry, immunohistochemistry and molecular genetics are required to distinguish the two components, as often the more aggressive one is predominant and masks the other. A 58-year-old man with history of nodal composite lymphoma presented with right exophthalmos and diplopia. A head CT scan showed an orbital tumor. A biopsy of the tumor revealed a mantle cell lymphoma predominating over a follicular lymphoma. Immunoglobulin heavy chain and light chain rearrangements analysis by PCR proved that both components of the orbital tumor were recurrences of the same nodal composite lymphoma diagnosed two years earlier. The nodal lymphoma was composed of a follicular lymphoma and an in situ mantle cell neoplasia. Consensus view is that dominant lymphoma should be treated when needed but taking into account if the mantle cell lymphoma is an in situ neoplasia and if it expresses CD5 and SOX11.

Mantle Cell Lymphoma Involving Skin: A Clinicopathologic Study of 37 Cases.

Mantle cell lymphoma (MCL) rarely involves the skin and the histologic and immunohistochemical features of this neoplasm at this site are under described. In this study, we report 37 skin specimens involved by MCL, representing 1.4% of total MCL biopsy specimens in our institution. The median age at time of skin involvement was 66 years (range, 36 to 85 y) and there was a male predilection of 2.7 to 1. The most frequently involved site was the skin of extremities, in 59.3% of patients, and 30 (81.1%) patients had advanced stage (III/IV) disease. Eleven (29.7%) patients presented with skin lesions as the first manifestation of MCL and 26 (70.3%) patients presented as relapse or progression of previously documented MCL and despite therapy for systemic MCL. Multiple skin lesions were more common (81.8%) in the former group whereas a solitary skin lesion was more frequent (65.4%) in the relapse/progression group (P=0.01). Thirty (81.1%) patients had skin nodules. Microscopically, the epidermis was spared with a grenz zone in all cases. A diffuse pattern of involvement was the most common architectural pattern (66.7%). In 27 (72.9%) patients, the MCL was either blastoid or pleomorphic variant, in 9 (24.3%) patients classic variant, and the disease was not further classified in 1 (2.7%) patient. The Ki-67 proliferation rate was higher in aggressive variants as compared with classic variant MCL (median 90% vs. 20%, P <0.01). In patients who presented skin lesions as a manifestation of disease relapse or progression, 16 patients initially had classic variant MCL and in 10 of the patients the MCL evolved over time (median interval: 4.1 y) to an aggressive variant at progression or relapse. The overall survival of patients with aggressive variant MCH was inferior to that of patients with classic variant MCL (median: 59 vs. 155.8 mo, P<0.05). In summary, MCL rarely involves the skin and correlates with relapse or progression of disease, aggressive morphologic features, and a poorer prognosis.

Mantle cell lymphoma of the cecum.

The authors have read with great interest the recently published article "Colon lymphomas: an analysis of our experience over the last 23 years" by Martín Domínguez V et al., a single center retrospective review of 29 patients diagnosed with colon lymphoma. The present report describes a case of mantle cell lymphoma (MCL) of the cecum that aims to improve the knowledge regarding this unusual clinical and endoscopic entity.

SOX11-negative Mantle Cell Lymphoma: Clinicopathologic and Prognostic Features of 75 Patients.

Studies have suggested that SOX11 expression has prognostic implications in patients with mantle cell lymphoma (MCL), but the data are controversial. In this study, we describe the clinicopathologic and prognostic features of 75 patients with SOX11-negative MCL. Compared with patients with SOX11-positive MCL, SOX11-negative MCL patients more frequently had leukemic non-nodal disease (21% vs. 4%, P=0.0001). SOX11-negative MCLs more often showed classic morphology (83% vs. 65%, P=0.005), were more often positive for CD23 (39% vs. 22%, P=0.02) and CD200 (60% vs. 9%, P=0.0001), and had a lower proliferation index (Ki67 23% vs. 33%, P=0.04). Overall survival (OS) was not significantly different between patients with SOX11-negative versus SOX11-positive MCL (P=0.63). High Ki67 index and blastoid/pleomorphic morphology were associated with shorter OS in both SOX11-negative (P<0.05) and SOX11-positive MCL groups (P<0.05). A high Mantle Cell Lymphoma International Prognostic Index (MIPI) predicted poorer prognosis in patients with SOX11-negative MCL (P<0.0001), but not SOX11-positive MCL (P=0.09). Nodal involvement and stage III/IV disease were associated with poorer outcome in patients with SOX11-positive MCL (P=0.03 and 0.04, respectively), but not SOX11-negative MCL (P=0.88 and 0.74, respectively). In summary, SOX11-negative MCL is characterized by more frequent leukemic non-nodal disease, classic morphology, more frequent expression of CD23 and CD200, and a lower Ki67 index. Prognostic factors in patients with SOX11-negative MCL include morphology, Ki67 index, and MIPI score.

Accuracy of diagnosing mantle cell lymphoma and identifying its variants on fine-needle aspiration biopsy.

BACKGROUND: Mantle cell lymphoma (MCL) is an incurable B-cell lymphoma portending an aggressive clinical course; the blastoid and pleomorphic morphological variants have an even worse prognosis. In addition, patients with classic morphology and a high proliferation index (HPI), also have reduced survival. Although variants have been defined, to the authors' knowledge the ability to detect these subtypes by fine-needle aspiration biopsy (FNAB) has not been described. METHODS: MCL cases diagnosed by lymph node FNAB with concurrent core needle biopsy were reviewed from 146 patients, accounting for 172 specimen pairs. FNAB and core needle biopsy diagnoses were compared to determine concordance rates. Flow cytometric immunophenotype and Ki-67 rates were evaluated. RESULTS: The classic subtype was diagnosed in 58% of cases (99 of 172 pairs) and variant morphology was diagnosed in 42% of cases (73 of 172 pairs) by histology. Twenty-nine patients presented with variant morphology whereas 28 underwent transformation. A nontraditional immunophenotype including loss of CD5 or FMC-7 and expression of CD23 and CD10 was found in 44% of variants (29 of 66 variants) and 19% of classic subtypes (18 of 94 classic subtypes) (P = .0008). Ki-67 rates averaged from 56% to 76% for blastoid and pleomorphic cases, 53% to 55% for MCL-HPI cases, and 17% to 19% for classic cases. The sensitivity and specificity to detect MCL variants by FNAB were 74% and 93%, respectively. CONCLUSIONS: The accuracy of diagnosing MCL is high when adequate samples for cytomorphology and flow cytometry are obtained. Subtyping variants by cytomorphology alone has challenges, but overall demonstrates high sensitivity and specificity. The performance of Ki-67 on cytology specimens is useful for detecting MCL with HPI.

[Clinicopathologic features and prognosis of mantle cell lymphoma: an analysis of 349 cases].

Objective: To investigate clinicopathologic features and prognostic factors of mantle cell lymphoma(MCL). Methods: The clinical data of 349 MCL patients diagnosed at Beijing Friendship Hospital from January 2004 to January 2016 were retrospectively collected. Corresponding histological sections were reviewed. Additional studies included immunohistochemical staining using the MaxVision two-step method, IgH/CCND1 fusion gene detection by fluorescent in situ hybridization (FISH), and correlative statistical analysis. Results: Of 349 patients with MCL, the median patient age was 61 years (range: 25-83 years, M∶F=2.7∶1.0) and the age of 243 patients ranged from 51 to 70 years (69.6%). Those with B symptoms accounted for 22.4% (70/313). Most of the patients presented with superficial lymphadenopathy and the clinical stage Ⅲ-Ⅳ accounted for 76.1% (235/309). Extranodal involvement was seen in 47.9% (148/309), among which the gastrointestinal tract accounted for 31.8% (47/148) and splenic involvement accounted for 15.4% (47/305). Three hundred and nine (88.5%) cases were of classical type and 40 (11.5%) cases were of aggressive variant type, and all were composed of proliferating lymphoid cells. All the tumors were positive for CD20 and cyclin D1, and 98.6% (344/349) tumors were weakly positive or positive for CD5. FISH test was positive in 12 cases that were CD5 negative and with cyclin D1 partial expression.Two hundred and forty-three (69.6%) patients had a median follow-up of 26 months (range: 3-108 months). The 3- and 5-year overall survival rates for patients were 63.0% and 34.8%, respectively. Single factor analysis showed that age of >60 years, splenic involvement, aggressive variant type, incompletely overlapping type [Based on the degree of overlap ≥90% and <90% between the follicular dendritic cell (FDC) meshwork and tumor cells, the tumors were divided into the completely overlapped type and incompletely overlapped type] and Ki-67 index >40% had poor prognosis (P<0.05). Multiple factor Cox proportional risk regression analysis after removing the aggressive variant type showed that age, splenic involvement, the degree of overlap between the FDC meshwork and tumor cells and Ki-67 index were independent prognostic factors for overall survival rate of MCL patients (P<0.05). Conclusions: MCL is more commonly found among middle-aged and elderly men. Patient age, splenic involvement, degree of overlap between FDC meshwork and tumor cells and Ki-67 index are the independent prognostic indicators for MCL.

Association of SOX11 gene expression withclinical features and prognosis of mantle cell lymphoma.

OBJECTIVE: To study the expression of SOX11 in the patients with mantle cell lymphoma (MCL) and explore the clinical values of SOX11 in MCL. PATIENTS AND METHODS: In the paraffin-embedded MCL tissues of 75 patients diagnosed in the Department of Hematology, Shanxi Tumor Hospital, were performed the immunohistochemical labeling of Ki67 and SOX11 by the EnVision method. Meanwhile, the expression of SOX11 mRNA was also detected by reverse transcriptase-polymerase chain reaction (RT-PCR), and the association of SOX11 with such prognostic indexes as pathological typing, staging, immunophenotyping, and MIPI was analyzed using the statistical method. RESULTS: The immunohistochemistry showed that 97% of cases expressed SOX11 positive, and the RT-PCR results showed that the expression of SOX11 mRNA in the MCL patients was significantly higher than those with reactive hyperplasia lymphoid [3.097 (1.311, 6.216) and 1.058 (0.302, 2.623, respectively (p<0.05). Higher expression of SOX11 mRNA was positively correlated with some good prognostic factors such as ECOG<2, no bone marrow involvement and low-risk according to the International Prognostic Index (IPI). The comparison of the survival curves between group SOX11 mRNA

[Clinicopathologic characteristics and prognositic indicators of tonsillar mantle cell lymphoma].

Objective: To investigate clinicopathological features and prognosis of tonsillar mantle cell lymphoma(TMCL). Methods: Clinical data of 25 patients with TMCL at Beijing Friendship Hospital, Capital Medical University from 2002 to 2016 were included. All the cases were reviewed microscopically. Various immunohistochemical stains were performed using the MaxVision two-step method. IgH/CCND1 gene fusion was detected by fluorescent in situ hybridization(FISH). Additionally, randomly selected 40 cases of non-tonsil MCL of the same period were compared. Results: Among all mantle cell lymphomas (MCL), TMCL accounted for 5.6%(25/449). The median age of the patients was 60 years(range: 44-82 years) with a M∶F ratio of 5.3 to 1.0. The main symptoms were sore throat and foreign body sensation and patients usually presented with enlargement or mass of tonsil. At the early stage of the disease, 18 cases(72.0%) were clinically misdiagnosed as tonsillitis. Lymph node involvement was present in 76.0%(19/25) of the patients. There were 4 cases(16.0%)with current splenic involvement, 11 cases(44.0%) with pharyngeal focal recidivism, and 3 cases(12.0%) with involvement of other non-lymphoid organs. Morphologically, tonsillar architectures were effaced at various degrees. Eighteen MCL cases showed classical type and 7 cases were blastoid variant. All tumors were positive for CD20 and cyclin D1. 92.0%(23/25) tumors showed weakly positive or positive expression for CD5. FISH test that IgH/CCND1 gene fusion was positive in two CD5 negative classical cases. 18 patients(72.0%) had a median follow-up time of 26 months(range: 6-81 months). The difference of survival rate between stage Ⅰ-Ⅱ and stage Ⅲ-Ⅳ patients was not statistically significant(P>0.05). Compared with NTMCL, TMCL was found to have higher proportion of stage Ⅰ-Ⅱ disease (χ(2)=12.789, P<0.01), lower the proportion of non-lymphatic organ involvement (χ(2)=8.125, P<0.01), and better prognosis (χ(2)=4.351, P=0.037). Conclusion: The incidence of TMCL is low and prone to be misdiagnosed as tonsillitis. Patients with TMCL are more likely at stage Ⅰ-Ⅱ at presentation and the prognosis is better than that of NTMCL.

Mantle cell lymphoma with a novel t(11;12)(q13;p11.2): a proposed alternative mechanism of CCND1 up-regulation.

Mantle cell lymphoma (MCL) is typically characterized by t(11;14), which places the IGH@ enhancer elements upstream of CCND1. This fusion results in up-regulation of CCND1 and consequently its protein product cyclin D1. Recent studies have shown that in MCL, mutations or translocations occurring within the 3' untranslated region (UTR) of the CCND1 gene can result in a truncated mRNA transcript that is more stable and associated with more aggressive disease. We identified a case of MCL showing cyclin D1 overexpression by immunohistochemistry and a t(11;12)(q13;p11.2) by conventional cytogenetic studies. Next-generation genomic sequencing indicated a chromosomal break through the CCND1 3'-UTR and fusion with a non-coding region of chromosome 12. We suggest that, in the absence of the typical CCND1/IGH@ fusion, this rearrangement promotes MCL pathogenesis by eliminating miRNA interaction elements within the 3'-UTR of the CCND1 mRNA transcript consequently resulting in CCND1 overexpression.

Reproducibility of SOX-11 detection in decalcified bone marrow tissue in mantle cell lymphoma patients.

Mantle cell lymphoma (MCL) usually harbors the t(11;14)(q13;q32) with overexpression of CCND1 mRNA and transcription of the cyclin D1 nuclear protein. Regardless of CCND1 status, most MCLs also express the SOX11 nuclear protein, which is thus helpful in the diagnosis of the rare CCND1-negative MCLs. Recently, SOX11 has been reported to be often negative in MCLs clinically resembling marginal zone lymphoma and recently defined as "leukemic non-nodal" MCL in the incoming revision of the WHO classification of lymphoid tumors, for which the bone marrow biopsy is commonly the first diagnostic approach. Due to the less aggressive clinical behavior of the latter MCLs, the reliable determination of the SOX11 antigen in decalcified tissue is mandatory. To this end, since little data are available in the literature, four commercially available anti-SOX11 antibodies (two polyclonal and two monoclonal) were tested on 21 positive staging bone marrow (BM) biopsies from cyclin D1/SOX11-positive MCL patients (17 fixed in B5, 4 in 10% buffered formalin) and on 9 positive BM biopsies from leukemic non-nodal MCL patients. The results were compared for specificity, sensitivity, staining strength and degree of an additional staining on myeloid precursors, also evaluating possible impact of the different fixatives used. Non-mantle cell lymphomas were also tested to address specificity. All reagents showed high sensitivity but the monoclonal code CMC38221001 provided the highest specificity and the lowest degree of non-lymphoid staining on myeloid cells. Formalin fixation generally improved the performance of most antibodies when compared to B5 fixation.

Assessing Metabolic Changes in Response to mTOR Inhibition in a Mantle Cell Lymphoma Xenograft Model Using AcidoCEST MRI.

AcidoCEST magnetic resonance imaging (MRI) has previously been shown to measure tumor extracellular pH (pHe) with excellent accuracy and precision. This study investigated the ability of acidoCEST MRI to monitor changes in tumor pHe in response to therapy. To perform this study, we used the Granta 519 human mantle cell lymphoma cell line, which is an aggressive B-cell malignancy that demonstrates activation of the phosphatidylinositol-3-kinase/Akt/mammalian target of rapamycin (mTOR) pathway. We performed in vitro and in vivo studies using the Granta 519 cell line to investigate the efficacy and associated changes induced by the mTOR inhibitor, everolimus (RAD001). AcidoCEST MRI studies showed a statistically significant increase in tumor pHe of 0.10 pH unit within 1 day of initiating treatment, which foreshadowed a decrease in tumor growth of the Granta 519 xenograft model. AcidoCEST MRI then measured a decrease in tumor pHe 7 days after initiating treatment, which foreshadowed a return to normal tumor growth rate. Therefore, this study is a strong example that acidoCEST MRI can be used to measure tumor pHe that may serve as a marker for therapeutic efficacy of anticancer therapies.

Large-scale identification of membrane proteins based on analysis of trypsin-protected transmembrane segments.

Integral membrane proteins are generally under-represented in routine proteomic analyses, mostly because of their relatively low abundance, hydrophobicity and lack of trypsin-cleavage sites. To increase the coverage of membrane proteomes, various strategies have been developed, targeting mostly the extra-membrane segments of membrane proteins. We focused our attention to the rather overlooked hydrophobic transmembrane segments. Such peptides can be isolated after carbonate stripping and protease "shaving" of membranes isolated by simple centrifugation procedure. The treated membranes with embedded hydrophobic peptides can then be solubilized in organic solvents, re-digested with CNBr, delipidated and subjected to LC-MS/MS analysis. We modified the original "hppK" method, and applied it for the analysis of human lymphoma cells. We identified 1224 proteins of which two-thirds were IMPs with 1-16 transmembrane segments. This method allowed us to identify 13 "missing proteins" - proteins with no previous evidence on protein level. BIOLOGICAL SIGNIFICANCE: Integral membrane proteins execute numerous essential functions and represent substantial part of eukaryotic proteomes. Our knowledge of their function and expression is, however, limited. Novel approaches extending our knowledge of membrane proteome are therefore highly desired. As we demonstrate here, a non-conventional method which targets rather overlooked hydrophobic transmembrane segments of integral membrane proteins has wide potential to provide the missing information on the membrane proteome. We show that it can deliver identification and potentially also quantification of hundreds of integral membrane proteins including the so called "missing proteins".

Prognostic Value of Ki-67 Index, Cytology, and Growth Pattern in Mantle-Cell Lymphoma: Results From Randomized Trials of the European Mantle Cell Lymphoma Network.

PURPOSE: Mantle-cell lymphoma (MCL) is a rather aggressive B-cell malignancy whose considerable variability of individual outcome is associated with clinical characteristics (Mantle Cell Lymphoma International Prognostic Index [MIPI]). The Ki-67 index is a strong independent prognostic factor; however, the biologic MIPI (MIPI-b) distinguishes only two groups, which does not appropriately depict the clinical heterogeneity. By using the cohort from the European MCL Younger and MCL Elderly trials, we aimed to evaluate the additional prognostic impact of cytology and growth pattern and to improve risk stratification with the Ki-67 index and MIPI. PATIENTS AND METHODS: Diagnostic tumor biopsies were reviewed by the European Mantle Cell Lymphoma Pathology Panel to determine Ki-67 index by using published guidelines, cytology, and growth pattern. We evaluated prognostic effects for overall survival (OS) by Cox regression. For the cohort used for MIPI-b development (German Low-Grade Lymphoma Study Group [GLSG] 1996 and GLSG2000), we checked whether the equally weighted combination of Ki-67 index (dichotomized at the validated 30% cutoff) and MIPI risk groups was adequate and compared the prognostic power of this modified combination to MIPI and MIPI-b for the MCL Younger/MCL Elderly cohort. RESULTS: The Ki-67 index was assessed in 508 of 832 patients (median age, 62 years). Blastoid cytology was associated with inferior OS independently of MIPI but not independently of the Ki-67 index. Growth pattern was not independently prognostic. The modified combination of the Ki-67 index and MIPI separated four groups with 5-year OS: 85%, 72%, 43%, and 17% (P < .001) and was more discriminative than MIPI and MIPI-b. CONCLUSION: Using the Ki-67 index is superior to using cytology and growth pattern as prognostic factors in MCL. The modified combination of the Ki-67 index and MIPI showed a refined risk stratification, reflecting their strong complementary prognostic effects while integrating the most relevant prognostic factors available in clinical routine.

Synchronous mantle cell lymphoma and prostate adenocarcinoma-is it just a coincidence?

Introduction: Synchronous occurrence of lymphomas and other cancers, mostly carcinomas are well established. The most of cases describe chronic lymphocytic leukemia as the leading lymphoproliferative disease with the tendency towards secondary malignancies development. Mantle cell lymphoma (MCL) has been described in only 2 cases to co-occur with prostate adenocarcinoma (PAC). There are scarce data about the connection between MCL and urology cancers. We presented the first case of synchronous occurrence of MCL and PAC in the same patient in Serbia. Case report: A 64-year-old male initially presented with fatigue, splenomegaly, and bicytopenia. The bone marrow biopsy specimen revealed extensive infiltration with MCL. During lymphoma staging procedure prostate enlargement (57 mm) was accidentally found by multislice- computed tomography (MSCT). The serum prostate specific antigen (PSA) was elevated (52 ng/mL; normal values ≤ 4 ng/mL). Transrectal ultrasound biopsy revealed PAC. High Gleason score determined high-risk locally advanced PAC. The patient underwent treatment with chemotherapy and hormone therapy due to the existence of double malignancies. Cyclophosphamide, doxorubicin, vincristine, prednisone (CHOP) was applied for MCL, and luteinizing hormonereleasing hormone (LHRH) agonist, triptorelin, for PAC. Partial response was obtained for MCL, and stable disease for PAC. In a 1.5-year observation period the patient was still disease progression free for both of malignancies. Conclusion: This case points aut that elderly males are in need for careful observation during the staging procedure for lymphoma. The literature data suggest that MCL patients are in increased risk for urologic malignancies development. However, the etiologic connection between these two entities, except male gender and older age, remains unclear.

Coexistence of hepatoma with mantle cell lymphoma in a hepatitis B carrier.

The coexistence of hepatocellular carcinoma (HCC) and non-Hodgkin's lymphoma (NHL) in the liver is rare. Reports show that these patients have cirrhotic livers or hepatitis virus infections before they develop HCC and NHL. We present a patient with hepatitis B virus infection who was transferred to our hospital with a newly detected liver mass; abdominal computed tomography examination showed one hypodense mass of 7 cm in diameter and multiple mesenteric and mediastinal lymph nodes. A liver tumor biopsy showed a hepatoma, and the pathologic findings from an inguinal lymph node excision showed mantle cell lymphoma. An immunohistochemical stain confirmed that the atypical lymphoid cells within the HCC were positive for the CD20, CD5 and cyclin D1 antigens. Taking these findings into account, the hepatic tumor was determined to be a HCC infiltrated by mantle cell lymphoma.

Ki-67 Labeling Indices in 'Classic' versus 'Blastoid' Mantle Cell Lymphomas--Proposed Cutoff Values for Routine Diagnostic Workup.

BACKGROUND: Mantle-cell lymphoma (MCL) is a unique entity of peripheral B-cell lymphoma that has a discrete morphologic, immunologic, and genetic phenotype, with more common 'classic' and less frequent 'blastoid' and 'pleomorphic' variants, associated with an aggressive clinical course. The aim of this study was to analyze proliferation (Ki-67) indices of 'classic' (c-MCL) and 'blastoid' (b-MCL) variants of a cohort of MCL and to suggest cut off values for the Ki-67 proliferation index in these two subsets. MATERIALS AND METHODS: MCL cases diagnosed over 4 1/2 years at Section of Histopathology, Department of Pathology and Laboratory Medicine, Aga Khan University Hospital, Karachi were retrieved and reviewed. Ki-67 labelling was scored and analysed. RESULTS: A total of 90 of cases of MCL were scrutinized. Mean age±SD was 60.2±12.5 years and the male to female ratio was 4:1, with 67 (75%) cases of c-MCL and 23 (25%) cases of b-MCL. Most samples were lymph node biopsies (n=68), whereas the remainder were from various extranodal sites The mean Ki-67 proliferation index was 29.5%±14.4% in classic variants and 64.4±15.2% for the blastoid variant, the difference being statistically significant (p=0.029). CONCLUSIONS: It was concluded that differential cut-off values of Ki-67 labeling may be used in more objective way to reliably classify MCL into classic or blastoid variants by diagnostic pathologists. We propose a <40 proliferative index to be suggestive of c-MCL and one of >50 for the blastoid variant.

Detection of t(12;14)(p13;q32) in a patient with IGH-CCND1 negative mantle cell lymphoma resembling ultra-high risk chronic lymphocytic leukemia.

T(12;14)(p13;q32) is a rare recurrent chromosomal translocation, which has only been identified in a small subgroup of mantle cell lymphoma (MCL) without typical t(11;14)(q13;q32). This rearrangement causes aberrant over-expression of cyclin D2 (CCND2), which disrupts the normal cell cycle. Here we report a subtle case of MCL with t(12;14)(p13;q32) that was initially misdiagnosed as ultra-high risk chronic lymphocytic leukemia (CLL). A 60-year-old male patient presented with obvious leukocytosis and progressive weakness. Morphology of peripheral blood and immunophenotyping by flow cytometry pointed to a diagnosis of chronic lymphocytic leukemia. Fluorescence in situ hybridization (FISH) using IGH-CCND1 probe was negative for CCND1 abnormality, but demonstrated IGH breakapart signals. The initial diagnosis of CLL was established and the patient was treated with six courses of immunochemotherpy with fludarabine, cyclophosphamide and rituximab (FCR). Complete remission (CR) was achieved at the end of treatment, but disease relapsed quickly. The patient was transferred to our hospital, flow cytometry using additional markers showed that the clonal cells were CD200+(dim), CD148+(strong), and chromosome analysis revealed a complex karyotype, 47, XY, t(12;14)(p13;q32), +12, del(9p21), which indicated over-expression of CCND2, and immunostaining showed strong positivity of SOX11 further confirming the characteristics of CCND1-negtive MCL. The final diagnosis was revised to rare subtype of MCL with CCND2 translocation and intensive regimens were employed. This confusable MCL case illustrates the importance of cytogenetic analysis and clinicopathologic diagnosis of this rare category of MCL.