Guess what: Chronic 13q14.3+/CD5-/CD23+ lymphocytic leukemia in blood and t(11;14)(q13;q32)+/CD5+/CD23- mantle cell lymphoma in lymph nodes!

Composite Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma and Mantle Cell Lymphoma; Small Cell Variant: A Real Diagnostic Challenge. Case Presentation and Review of Literature

Patient: Male, 57-year-old

Final Diagnosis: CLL/SLL and MCL composit lymphoma

Symptoms: Abdominal pain

Medication:—

Clinical Procedure: BM examination

Specialty: Hematology

Composite mantle cell lymphoma and chronic lymphocytic leukemia/small lymphocytic lymphoma

BACKGROUND

Composite mantle cell lymphoma (MCL) and chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) is rare, as less than 20 cases have been reported so far. However, this entity may be under-diagnosed because the two lymphomas are very similar in morphology and immunophenotype. Previous cases were mostly diagnosed with immunohistochemistry, but flow cytometry may play an important role in the detection of two tumors in the same specimen, thus achieving an accurate diagnosis. By definition, a composite lymphoma is two demarcated lymphomas occurring at the same anatomic site. Therefore, immunohistochemistry is still needed to identify the topographic relation of these two tumors. Our reported case illustrates the pitfalls in the diagnostic process and we recommend two standard panels with new markers for an accurate diagnosis of this composite lymphoma.

METHOD

FACSCanto II is used with antibodies, including CD5, CD10, CD19, CD20, CD22, CD23, CD43, CD79b, CD200, kappa, and lambda. Immunohistochemical stains include PAX-5/CD5 dual stain, Cyclin D1, SOX11, and LEF-1.

RESULTS

CLL/SLL is positive for CD5, CD19, CD23, CD43, and CD200, with dim expression of CD20, CD22, CD79b, and kappa. MCL is positive for CD5, CD19, CD20, CD22, CD79b, kappa, and negative for CD23, CD43, and CD200. Immunohistochemical stains show that PAX-5/CD5 stains the entire tumor population. Cyclin D1 and SOX11 only stain the central portion that represents MCL and LEF-1 stains the periphery that represents CLL/SLL.

CONCLUSIONS

We recommend the use of the above panels for flow cytometry and immunohistochemistry, respectively. LEF-1 is specific for CLL/SLL; and CD200 is helpful to distinguish CLL/SLL from MCL. © 2017 International Clinical Cytometry Society.

Composite mantle cell lymphoma and chronic lymphocytic leukemia/small lymphocytic lymphoma: a clinicopathologic and molecular study

Mantle cell lymphoma (MCL) and chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) share many features and both arise from CD5+ B-cells; their distinction is critical as MCL is a more aggressive neoplasm. Rarely, cases of composite MCL and CLL/SLL have been reported. Little is known about the nature of these cases and, in particular, the clonal relationship of the 2 lymphomas. Eleven composite MCL and CLL/SLL cases were identified. The clinical, morphologic and immunophenotypic features of the MCL and CLL/SLL were characterized. IGH (immunoglobulin heavy chain) gene analysis was performed on microdissected MCL and CLL/SLL components to assess their clonal relationship. Ten patients had lymphadenopathy, and 7 patients had bone marrow involvement. The MCL component had the following growth patterns: in situ (n = 1), mantle zone (n = 3), nodular and diffuse (n = 3), diffuse (n = 3), and interstitial in the bone marrow (the only patient without lymphadenopathy) (n = 1); 6 MCLs had blastoid or pleomorphic and 5 small lymphocytic features. The CLL/SLL component was nodular (n = 9) or diffuse (n = 2). All MCL were CD5(+) and cyclin D1(+) with t(11;14) translocation. All CLL/SLL were CD5(+), CD23(+) and negative for cyclin D1 or t(11;14). IGH gene analysis showed that the MCL and CLL/SLL components displayed different sized fragments, indicating that the MCL and CLL/SLL are likely derived from different neoplastic B-cell clones. The lack of a clonal relationship between the MCL and CLL/SLL components suggests that MCL and CLL/SLL components represent distinct disease processes and do not share a common progenitor B-cell.

Mantle cell lymphoma as a component of composite lymphoma: clinicopathologic parameters and biologic implications

Composite lymphoma is a rare circumstance in which 2 or more distinct types of lymphoma occur in a single anatomical location. Although composite lymphoma has been increasingly identified with the advent of molecular genetic techniques, this topic has only rarely been a specific focus of the medical scientific literature. In this review, we focus on mantle cell lymphoma occurring as a major pathologic component of composite lymphoma and emphasize the clinicopathologic features of these tumors and associated biologic implications. To date, 26 cases of composite lymphoma including a component of mantle cell lymphoma have been previously published. Issues of clonal relatedness between the individual lymphoma components and emerging biologic implications as well as potential diagnostic pitfalls are evaluated.

Treatment of synchronous mantle cell lymphoma and small lymphocytic lymphoma with bendamustine and rituximab

Herein, we describe a case of a female patient in whom B cell chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL) were diagnosed simultaneously. She presented with anemia, thrombocytopenia and splenomegaly. Flow cytometry demonstrated two immunophenotypically distinct CD5-positive monoclonal B cell populations. Peripheral blood fluorescence in situ hybridization (FISH) was positive for IGH/CCND1, consistent with t(11;14) translocation. She received 6 cycles of bendamustine 70 mg/m(2)/day for 2 days and rituximab on the first day every 4 weeks along with granulocyte-colony stimulating factor. She had an excellent response, and repeat computed tomography after her third cycle of chemotherapy revealed no organomegaly or lymphadenopathy. Her peripheral blood lymphocytosis also resolved. Bone marrow examination revealed no detectable flow-cytometric evidence of MCL or CLL. Repeat cytogenetic and FISH analysis were also normal. The patient remains in complete remission 20 months after her initial diagnosis and is receiving maintenance rituximab 375 mg/m(2) weekly for 4 weeks every 6 months for 2 years.

Cytogenetics of lymphomas

Cytogenetic analysis is now a routine part of the diagnosis and management of a significant number of lymphoid malignancies. Whilst conventional cytogenetics remains the most comprehensive method for assessing chromosome abnormalities, the technical difficulties associated with conventional cytogenetics in most lymphomas has resulted in increased use of fluorescence in situ hybridisation (FISH) to identify specific abnormalities that are useful in either the diagnosis or management of these disorders. The finding of one of the Burkitt's translocations is of major importance in the diagnosis of Burkitt's and Burkitt's-like lymphomas, whereas the t(14;18), although seen in most follicular lymphomas (FL), is not usually required to make a diagnosis. Thus, whilst cytogenetics may be of interest in FL, it is not an essential part of the diagnostic work-up. Conventional cytogenetics may be useful for identifying markers of resistance to Helicobacter pylori therapy in MALT lymphomas. In disorders such as Hodgkin lymphoma, hairy cell leukaemia and lymphoplasmacytoid lymphoma, although many cytogenetic abnormalities have been observed, no consistent or specific abnormalities have been identified and so, at this point in our knowledge of the genetics of these disorders, cytogenetics cannot be considered a useful test for either diagnosis or prognosis. In contrast, the diagnosis of mantle cell lymphoma is now dependent upon the identification of the 11;14 translocation that results in cyclin D1 up-regulation. It is widely acknowledged that FISH is the most consistently useful test to identify the juxtaposition of the CCND1 and IGH genes in mantle cell lymphoma and is regarded as the 'gold standard'. FISH also has a role in identifying genetic abnormalities of prognostic significance in chronic lymphocytic leukaemia. Given the wealth of genetic and cytogenetic abnormalities that are continuing to be found in chronic lymphoid malignancies, it will be some time before the optimal use of both conventional cytogenetics and FISH is established in the diagnosis and management of lymphomas.