Linfoma de células B primario de mama en una paciente con sida. Presentación de un caso y revisión de la literatura / Primary B-cell lymphoma of the breast in an AIDS patient. Case report and literature review

Los LNH constituyen la segunda neoplasia más frecuente en pacientes con VIH. Estas neoplasias están ligadas a la inmunodeficiencia, suelen ser de período de latencia prolongado y más frecuentes en hombres. Más del 95% de estas neoplasias son de fenotipo B, de alto grado de malignidad, extranodales y representan la causa de muerte en un 12% al 16% de los casos. El linfoma no Hodgkin primitivo de mama (LPM) es una entidad infrecuente, que representa el 2,2% de todos los linfomas extranodales y el 0,5% de todas las neoplasias malignas de la mama. Se presenta una mujer con sida y linfoma primario de mama. (AU)

NHL is the second most common neoplasm in patients with HIV. It is linked to immunodeficiency, tends to have a long latency period and is more common in men. More than 95% of these neoplasms are of phenotype B, high-grade, extranodal and are the cause of death in 12% to 16% of cases. Primitive non-Hodgkin lymphoma of the breast is a rare entity, accounting for 2.2% of all extranodal lymphomas and 0.5% of all breast malignancies. A woman with AIDS and primary breast lymphoma is presented. (AU)

Follicular lymphoma with a predominantly diffuse growth pattern with 1p36 deletion: a clinicopathologic analysis of eight cases / 中华病理学杂志

Objective: To investigate the clinical and pathologic features and diagnosis of follicular lymphoma (FL) with a predominantly diffuse growth pattern (DFL) with 1p36 deletion. Methods: Eight cases of DFL with 1p36 deletion diagnosed at Department of Pathology, Beijing Friendship Hospital, Capital Medical University (n=5) and the Affiliated Cancer Hospital of Zhengzhou University, Henan Cancer Hospital (n=3) from January 2017 to January 2023 were included. Their clinicopathologic features and follow-up data were analyzed. Immunohistochemistry and fluorescence in situ hybridization (FISH) were performed. Results: There were five males and three females, with a median age of 67 years, and inguinal lymphadenopathy was found as the main symptom. Histologically, similar morphologic features were sheared among all cases, with effaced nodal structure and characterized by proliferation of centrocytes in a diffuse pattern, with or without follicular components. The germinal center-related markers such as CD10 and/or bcl-6 were expressed in the tumor cells, and 1p36 deletion but not bcl-2 translocation was appreciable in these cases. Conclusions: DFL with 1p36 deletion is a rare subtype of FL, with some overlaps with other types of FL or indolent B-cell lymphomas in their pathologic features. An accurate diagnosis requires comprehensive considerations based on their clinical, pathologic, immunohistochemical, and molecular features.

Analysis of 9 cases of pediatric-type follicular lymphoma / 中华儿科杂志

Objective: To summarize the pathological diagnosis, clinical features, treatment methods and outcomes of pediatric-type follicular lymphoma (PTFL). Methods: Clinical data including the pathology, clinical features, treatment methods, and follow-up results of 9 PTFL patients admitted to Henan Cancer Hospital from February 2017 to February 2023 were analyzed retrospectively. Results: The age of onset in 9 children was 6 to 18 years, all the patients were males. The clinical manifestation was local painless lymph node enlargement in the head and neck, with a stage of Ⅰ-Ⅱ. The histomorphological characteristics of PTFL were similar to those of classic follicular lymphoma (FL). The germinal center of most follicles were enlarged, the mantle zone disappeared, centroblasts were easily visible, and the histological grade were mostly grade Ⅲ, which may be accompanied by the "starry sky" phenomenon. Monoclonal peaks can be seen in B cell clonal rearrangements (BCR). Immunohistochemistry (IHC) showed CD20 positive, CD10 positive, Bcl-6 positive, Bcl-2 negative, C-myc negative, and Ki-67 was 70%-95%. Fluorescence in situ hybridization (FISH) test was negative for t (14, 18), Bcl-2 translocation, and C-myc translocation. Six cases underwent surgical resection, and 3 cases underwent surgical resection combined with chemotherapy. Up to February 2023, with a follow-up time of 45 to 72 months, all children survived without any recurrence and were in a complete remission state. Conclusions: PTFL is mainly characterized by adolescent male onset, with early clinical manifestations and pathological manifestations of high-level histological status, high proliferation index, and lack of t (14; 18)/Bcl-2 translocation and Bcl-2 expression. It is mainly treated by localized surgical excision and has a good prognosis.

Intravascular large B-cell lymphoma: The Great Imitator

Intravascular large B-cell lymphoma (IVLBCL) is a rare subtype of diffuse large B-cell lymphoma with an estimated incidence of less than one per million. Unlike other hematopoietic malignancies, lymphadenopathy and hepatosplenomegaly are uncommon, and patients typically present with nonspecific symptoms. IVLBCL presents a diagnostic challenge and patients are usually diagnosed late in the disease course, if at all, and the prognosis is poor. The differential diagnosis is broad, and physicians often pursue multiple diagnostic possibilities during patient workup. We present a case of IVLBCL discovered at autopsy in an 80-year-old male who presented with history and symptoms pointing to the tick-borne illness ehrlichiosis.

Splenic diffuse red-pulp small B-cell lymphoma associated with hepatitis B virus: a report of two cases / Linfoma esplênico difuso da polpa vermelha, de linfócitos B pequenos, associado ao vírus da hepatite B: relato de dois casos

ABSTRACT CONTEXT: Splenic diffuse red-pulp small B-cell lymphoma is a rare disease, representing less than 1% of all non-Hodgkin lymphomas (NHL). This entity is characterized by involvement of bone marrow sinusoids and peripheral blood. The majority of cases are at an advanced stage when diagnosed. Its pathogenesis is still poorly understood. CASE REPORTS: We report on two patients with chronic non-replicating hepatitis B virus (HBV) who developed splenic diffuse red-pulp small B-cell lymphoma. Both of them were in stage IV at diagnosis and evolved with aggressive disease. Both of them achieved a complete response through chemotherapy, but one of them died due to infectious complications during bone marrow transplantation. The other decided not to undergo transplantation and continues not to show any evidence of disease today (three years after treatment). Some studies have shown a possible association between B-cell NHL and HBV. Nonetheless, the mechanism through which this oncogenic virus interacts with B-cell NHL is still poorly understood. HBV is lymphotropic and may insert into the host's genome, thus causing overexpression of oncogenes and downregulation of tumor suppressor genes. Therefore, chronic stimulation by HBV can increase B-cell proliferation, which promotes monoclonal expansion of these cells and results in malignancy. CONCLUSION: HBV may be implicated in the pathogenesis of this lymphoma, although no direct association between these two entities could be proved in the present study. Further investigations are necessary.

RESUMO CONTEXTO: Linfoma esplênico difuso da polpa vermelha, de linfócitos B pequenos, é uma doença rara, representando menos do que 1% de todos os linfomas não Hodgkin. Essa entidade é caracterizada por envolvimento de sinusoides da medula óssea e sangue periférico. A maioria dos casos está em estádio avançado ao diagnóstico. Sua patogênese ainda é pouco compreendida. RELATOS DE CASOS: Reportamos dois pacientes com vírus da hepatite B (HBV) crônica não replicante que desenvolveram linfoma esplênico difuso da polpa vermelha, de linfócitos B pequenos. Ambos estavam em estádio IV ao diagnóstico e evoluíram com doença agressiva. Ambos alcançaram resposta completa com a quimioterapia, porém um deles evoluiu a óbito por intercorrências infecciosas durante o transplante de medula óssea e o outro optou por não realizar o transplante e encontra-se sem evidência de doença até os dias atuais (três anos após tratamento). Alguns estudos demonstraram a possível associação entre linfomas não Hodgkin B e HBV. Entretanto, o mecanismo pelo qual esse vírus oncogênico interage com linfoma não Hodgkin B ainda é pouco compreendido. HBV é linfotrópico e pode se inserir no genoma do receptor, causando superexpressão de oncogenes e downregulation de genes supressores tumorais. Portanto, o estímulo crônico pelo HBV pode aumentar a proliferação de células B, promovendo expansão monoclonal dessas células, resultando em malignidade. CONCLUSÃO: HBV pode estar implicado na patogênese desse linfoma, entretanto, uma associação direta entre essas duas entidades não pôde ser provada no presente estudo e investigações adicionais são necessárias.

Linfoma cutáneo primario de células B centrofolicular: un desafío diagnóstico / Primary cutaneous follicular B-cell lymphoma: a diagnostic challenge

El linfoma cutáneo primario de células B (LCPCB) centrofolicular corresponde a una proliferación neoplásica infrecuente e indolente de células del centro germinal confinadas a la piel. Se reporta y revisa un caso de LCPCB centrofolicular. Paciente femenino de 76 años, con antecedentes de hipertensión arterial y resistencia a la insulina. Consultó por aumento de volumen frontal de dos años de evolución. Al examen físico destacaba un nódulo único en región frontal derecha. La ecografía de partes blandas fue compatible con quiste epidérmico. La histopatología demostró en dermis profunda, tejido adiposo subcutáneo y tejido muscular estriado una proliferación linfoide sólida dispuesta en patrón nodular y difuso. A la inmunohistoquímica (IHQ), los linfocitos fueron CD20 y BCL-6 positivo, con un Ki-67 de 60% y BCL-2, CD3, CD5 y CD10 negativo. El estudio de diseminación tumoral resultó negativo. El LCPCB centrofolicular concentra el 60% de todos los LCPCB. Se presenta en promedio a los 51 años. Se ha descrito asociación con Borrelia burgdorferi, VIH, virus hepatitis C y virus Epstein-Barr. Clínicamente corresponde a un nódulo eritematoso y asintomático, localizado preferentemente en cabeza, cuello y tronco. La IHQ es fundamental para diferenciarlo de otros tipos de LCPCB. Habitualmente, el tratamiento es con radioterapia o cirugía escisional. La supervivencia es de un 95% a 5 años. Se presenta este caso dado que el LCPCB centrofolicular corresponde a un tumor cutáneo infrecuente, con múltiples diagnósticos diferenciales, que requiere de un alto índice de sospecha para lograr un diagnóstico y tratamiento oportuno.

The primary cutaneous follicle center lymphoma (PCFCL) corresponds to an infrequent and indolent neoplastic proliferation of germinal center cells confined to the skin. A case of PCFCL is reported and revised. Results: A female patient, 76 years old, with arterial hypertension and insulin resistance. Sough attention for an increase in size of the frontal region over the course of two years. Upon physical examination, a single nodule was noted in the right frontal region. A soft tissue ultrasound identified results indicative of an epidermal cyst. The histopathology revealed a proliferation of solid lymphoid arrayed in a diffuse and nodular pattern in the deep dermis, subcutaneous adipose tissue, and striated muscular tissue. Immunohistochemistry (IHQ) revealed CD20 and BCL-6 positive lymphocytes, with 60% of Ki-67 and BCL-2, CD3, CD5, and CD10 negative. A study of tumor dissemination resulted negative. The PCFCL concentrates 60% of all primary cutaneous B cell lymphomas (PCBCL). It presents at an average of 51 years of age. It has been described association with Borrelia burgdorferi, HIV, hepatitis C virus and Epstein-Barr virus. Clinically it corresponds to an erythematous and asymptomatic nodule, found frequently on the head, neck and trunk. The IHQ is essential to differentiate it from other types of PCBCL. It is usually treated with radiotherapy or excisional surgery. Survival is 95% over 5 years. This case is presented because the PCFCL corresponds to an infrequent cutaneous tumor, with multiple differential diagnoses, requiring a high index of suspicion to achieve an opportune diagnostic and treatment.

Primary cutaneous follicle center lymphoma simulating basal-cell carcinoma on the nasal ala

Primary cutaneous B-cell lymphomas (PCBCLs) constitute 25% of all primary cutaneous lymphomas. They present in the skin with no evidence of systemic or extracutaneous disease at the time of diagnosis, after adequate staging. Primary cutaneous B-cell lymphomas differ significantly from their nodal counterparts in relation to both clinical behavior and prognosis. The distinction between primary and secondary B-cell lymphomas is essential for defining prognosis/course of action. Such distinction is also very difficult to make, since primary and secondary B-cell lymphomas are clinically and histologically indistinguishable. We report the case of a patient with primary cutaneous follicle center lymphoma who underwent surgical excision.

Bone Marrow Flow Cytometry in Staging of Patients With B-cell Non-Hodgkin Lymphoma

BACKGROUND: Bone marrow biopsies are routinely performed for staging patients with B-cell non-Hodgkin lymphoma (NHL). In addition to histomorphological studies, ancillary tools may be needed for accurate diagnosis. We investigated the clinical utility of multiparameter flow cytometric examination of bone marrow aspirates. METHODS: A total of 248 bone marrow specimens from 232 patients diagnosed with B-cell NHL were examined. Monoclonal antibodies directed against CD19, CD20, CD10 (or CD5), and kappa and lambda immunoglobulins were used. Multi-stage sequential gating was performed to select specific cells of interest, and the results were compared with bone marrow histology. RESULTS: The concordance rate between histomorphology and flow cytometry was 91.5% (n=227). Eight cases (3.2%) were detected by flow cytometry alone and were missed by histomorphology analysis, and 6 of these 8 cases showed minimal bone marrow involvement (0.09-2.2%). The diagnosis in these cases included large cell lymphoma (n=3), mantle cell lymphoma (n=3), and mucosa-associated lymphoid tissue (MALT) lymphoma (n=2). Thirteen cases were histopathologically positive and immunophenotypically negative, and the diagnoses in these cases included diffuse large cell lymphoma (n=7), T-cell/histiocyte-rich large B-cell lymphoma (n=2), anaplastic lymphoma kinase (ALK)-positive large B-cell lymphoma (n=1), follicular lymphoma (n=1), MALT lymphoma (n=1), and unclassifiable lymphoma (n=1). CONCLUSIONS: Multi-color flow cytometry can be a useful method for assessing bone marrow in staging NHL and also plays a complementary role, especially in detecting small numbers of lymphoma cells.

Primary Intestinal Lymphoma: A Clinicopathological Study.

Introduction: Primary intestinal lymphoma (PIL) is defined as an extranodal lymphoma arising in the intestine. This study includes 11 PILs. Objectives: The objective of this study was to evaluate the clinicopathological characteristics of primary non-Hodgkin's lymphoma (NHL) in the small and large intestine. All cases were reclassified according to the World Health Organization classification of lymphoma in 2001. Immunohistochemistry (IHC) was used to confirm the histopathological diagnosis. Materials and Methods: Eleven cases of primary non-Hodgkin in the small and large intestine were studied retrospectively in a 5 year period. There were seven cases of resected intestinal specimens and four biopsy specimens. Five cases from ileum and two cases each from caecum and duodenum and one case each from jejunum and duodenum. Hematoxylin and eosin stained sections were studied with light microscopy and IHC for CD5, 20, 21 and cyclin D1 were done. Results: It is a retrospective study of 11 cases of intestinal lymphomas. Abdominal pain and abdominal lump were two main common presenting symptoms. NHLs were more common in the small intestine. PILs are common in adults (75% above 46 years) with male preponderance. All were NHLs and B-cell type. Five cases were diffuse large B-cell lymphoma and four cases each were mucosa-associated lymphatic tissue lymphoma and follicular lymphoma. One case was lymphomatoid polyposis or mantle cell lymphoma. Conclusion: PILs is rare and differs significantly from their gastric counterpart, not only in pathology but also with regard to clinical features, management and prognosis. Due to the lack of characteristic symptoms and a low incidence rate, PIL is misdiagnosed until serious complications occur, such as perforation and bleeding and hence needs to be accurately diagnosed.

Case for diagnosis

We report the case of a 81-year-old female patient who had a two-year history of violet-colored erythematous tumors on both legs. Histopathological and immunohistochemical examinations confirmed the diagnosis of primary cutaneous large B-cell lymphoma, leg type. This rare, cutaneous lymphoma affects predominantly elderly females. Clinically, patients present with tumoral lesions on one or both legs (worst prognosis). Diagnosis is based on clinical, histopathological and immunohistochemical findings. The strong expression of BCL2, BCL6, MUM-1 and CD20, and the positivity for Ki67 antigen confirm the diagnosis. R-CHOP chemotherapy regimen (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone) is the most widely accepted treatment.

Case report of a metachronous multiple tumor: Mantle cell lymphoma in the orbital region associated with epithelial malignancies at other sites / Tumor múltiplo metacrônico: linfoma do manto na região orbital associado a neoplasias malignas epiteliais em outros sítios - relato de caso

Here we report the case of a 73-year-old man who was diagnosed with metachronous, multiple primary tumors with non-Hodgkin B-cell mantle cell lymphoma involving the orbit on the basis of biopsy and immunohistochemistry in 2012. The patient had been diagnosed with non-Hodgkin small cell lymphoma and basal cell skin carcinoma in 2010 and intestinal adenocarcinoma with metastasis to the regional lymph nodes in 2011, thus representing a typical case of metachronous, multiple primary tumors. Mantle cell lymphoma is a rare disease and its prognosis is quite poor, particularly when it is associated with other metachronous malignancies. Therefore, physicians should consider mantle cell lymphoma as a differential diagnosis for neoplasms of the orbit.

Relatamos um caso de linfoma não-Hodgkin de células B subtipo células do manto acometendo região orbital, com o diagnóstico confirmado pela biópsia e testes imuno-histoquímicos em 2012. O paciente apresentava história de linfoma não-Hodgkin de pequenas células em 2010, carcinoma basocelular de pele no mesmo ano e adenocarcinoma intestinal com metástase para linfonodos regionais em 2011; caracterizando um caso de tumor primário múltiplo metacrônico. O linfoma de células do manto é uma doença rara, ainda mais quando associado a outras neoplasias metacrônicas, apresentando prognóstico bastante reservado. Dessa forma, deve estar entre os diagnósticos diferenciais de neoplasias da órbita.

Primary cutaneous centrofollicular lymphoma with a good response to radiotherapy / Linfoma centrofolicular cutaneo primario com boa resposta a radioterapia

Primary cutaneous lymphomas have different clinical behavior and prognosis than systemic lymphomas of similar histological subtype. About 30% of non-Hodgkin lymphomas involve extranodal tissues, the skin being the second most affected body organ after the gastrointestinal tract (approximately 18%). According to the EORTC (European Organization for Research and Treatment of Cancer) classification, the lymphoma centrofollicular is indolent, since the lesions increase in size slowly over the years and spread to extracutaneous sites is uncommon. Based on this, radiotherapy has been considered the treatment of choice by many studies. We present the case of a patient who had cutaneous centrofollicular scalp lymphoma for 1 year and showed good response to radiotherapy.

Os linfomas cutâneos primários têm comportamento clínico e prognóstico diferente dos linfomas sistêmicos de subtipo histológico semelhante. Cerca de 30% dos linfomas não-Hodgkin acometem tecidos extranodais, sendo a pele o segundo órgão mais envolvido após o trato gastrointestinal (aproximadamente 18%). De acordo com a classificação EORTC (European Organization for Research and Treatment of Cancer), o linfoma centrofolicular cutâneo é indolente, uma vez que as lesões aumentam de tamanho lentamente ao longo dos anos e a disseminação para sitios extracutâneos é incomum. Com base nisso, a radioterapia tem sido apontada como o tratamento de primeira escolha por muitos estudos. Apresentamos um caso de paciente com linfoma cutâneo centrofolicular no couro cabeludo há 1 ano e que apresentou boa resposta à radioterapia.

Lymphoma at King Hussein Medical Center: a histopathologic review

To determine the spectrum of various types of malignant lymphoma in children and adults at King Hussein Medical Center according to the World Health Organization classification 2001. A retrospective review of the histopathological subtypes of all primary lymphoma cases was conducted at Princess Iman Research and Laboratory Sciences Center at King Hussein Medical Center during the period between January 2004 and December 2008. A total of 485 patients were studied regarding: age, gender, and Lymphoma type using the World Health Organization classification of lymphoid neoplasms. Descriptive analysis using frequencies was used to describe the study variables. Two hundred seventy-four [56.5%] cases were males and 211 [43.5%] were females. Their ages ranged between two and ninety years. A total of 61 [12.6%] patients were children and 424 [87.4%] patients were > 14 years old. Of 485 patients included in the study, 342 patients [70.5%] had non-Hodgkin's lymphoma and 143[29.5%] had Hodgkin's lymphoma. Two hundred twenty nine [47.2%] of affected patients aged 50 years and above, non-Hodgkin's Lymphoma accounted for 206 patients [90%] of them. Of all pediatric lymphoma cases, Hodgkin's lymphoma accounted for 41% [25 cases] and Non-Hodgkin's Lymphoma 59% [36 cases]. Burkitt's lymphoma was the predominant lymphoma in children. In the adult NHL group, diffuse large B-cell lymphoma was the most common followed by follicular lymphoma. In the HL group, the nodular sclerosis variant was the most frequent [63.6%, 91 patient] followed by the mixed cellularity type [20.3%, 29 patient]. Distribution and patterns of lymphoma differs between children and adults. Diffuse large B-cell lymphoma is the most commonly encountered lymphoma in adults. Burkitt's lymphoma and Hodgkin's lymphoma are the predominant childhood lymphomas.

Modulation of IL-10/IL-10R expression by mafosfamide, a derivative of 4-hydroxycyclophosphamide, in a rat B-cell lymphoma

We have already shown that IL-10 plays an important role in immunosuppression and metastatic dissemination in the rat B-cell lymphoma L-TACB model. It was suggested that the up-regulation of IL-10 production and IL-10 receptor (IL-10R) expression would be part of the transition from primary tumor to metastatic phenotype and that IL-10, besides its immunosuppressive activity, may act as a growth factor for metastatic L-TACB cells. The treatment of L-TACB-bearing rats with a single low-dose cyclophosphamide decreased IL-10 production, reverted immunosuppression and induced the immunologic rejection of tumor metastasis without any effect on primary tumor growth. Our current aim was to investigate the effects of cyclophosphamide on the expression of IL-10 and IL-10R on primary and metastatic L-TACB cells. Considering that cyclophosphamide is a prodrug, we used mafosfamide, a compound that yields in vitro the same active metabolites as cyclophosphamide does in vivo. Mafosfamide induced down-regulation of IL-10 production and IL-10R expression on metastatic cells and, concomitantly, inhibited metastatic cell proliferation. We suggest that mafosfamide would inhibit the regulatory loop mediated by the IL-10/IL-10R system and, as a consequence, metastatic cell proliferation. These results may have a considerable impact on the design of new therapies for metastatic lymphomas.

Primary cardiac diffuse large B-cell lymphoma with activated B-cell-like phenotype.

Primary cardiac lymphoma (PCL) is a rare and fatal disorder. It may often mimic other common cardiac tumors like cardiac myxoma because of similarities in the clinical presentation. We report a case of PCL of diffuse large B-cell type, in a 38-year-old, immunocompetent male who presented with superior vena cava syndrome that was excised as a myxoma. Histology revealed a large cell population diffusely and strongly expressing CD45, CD20, MUM1/IRF4 and FOXP1 hinting at an activated B-cell (ABC)-like phenotype. After four cycles of Rituximab with CHOP (cyclophosphamide, hydroxydaunorubicin, Oncovin, and prednisolone) the tumor regressed completely but the patient had a relapse and subsequently succumbed to the disease confirming the aggressive nature. The aggressive behavior of PCL may be possibly linked to its ABC-like origin.

Polymerase chain reaction-Based clonality analysis of cutaneous B-cell lymphoproliferative processes

Introduction: The differential diagnosis of B-cell lymphoproliferative processes remains a challenge for pathologists, dermatologists and oncologists, despite advances in histology, immunohistochemistry and molecular biology. Objective: Evaluate aid and limitations of clonality analysis in the diagnosis of primary cutaneous B-cell lymphomas and B-cell pseudolymphomas. Methods: This study included 29 cases of B-cell lymphoproliferative processes classified as primary cutaneous B-cell lymphomas (13), B-cell pseudolymphomas (6) and inconclusive cases (10) using histology and immunohistochemistry. The clonality analysis was performed by polymerase chain reaction analysis of immunoglobulin light chain and heavy chain rearrangements. Results: DNA quality was shown to be generally poor; eight samples were inadequate for polymerase chain reaction analysis. The results showed monoclonality in eight of the primary cutaneous B-cell lymphomas and polyclonality in four of the B-cell pseudolymphomas. In addition, monoclonality was shown in two of the inconclusive cases by histology and immunohistochemistry, demonstrating the utility of polymerase chain reaction as an ancillary diagnostic tool for primary cutaneous B-cell lymphomas. Discussion: The low quality DNA extracted from these cases demanded the use of an IgH protocol that yielded small fragments and IgK. Both methods used together improved detection. Conclusion: Use of the two protocols, immunoglobulin heavy chain FR3-trad and immunoglobulin light chain-Kappa Biomed protocols for clonality analysis improved diagnostic accuracy.