Diffuse large B-cell lymphoma with spindle cell features

Signet ring cell-like diffuse large B-cell lymphoma involving the breast: a case report

BACKGROUND

Diffuse large B-cell lymphoma (DLBCL) with signet ring cell components is extremely rare. Here, we present a case of DLBCL with signet ring cell components involving the breast, which can be easily confused with invasive lobular carcinoma of the breast or metastatic signet ring cell carcinoma of gastrointestinal origin.

CASE PRESENTATION

A 66-year-old woman presented with a painless mass in her left breast. Enhanced magnetic resonance imaging (MRI) of the breast revealed a 42 × 29 × 28 mm mass in the left breast. Histological examination revealed a diffuse or scattered arrangement of round cells mixed with signet ring-like cells. Immunohistochemically, the neoplastic cells were positive for PAX-5, CD79a, CD20, Bcl-6, and MUM-1 but and negative for cytokeratin, ER, PR, E-cadherin, and P120. The Ki-67 proliferation index was approximately 70%. Fluorescence in situ hybridisation (FISH) demonstrated non-rearrangement of Bcl-2, Bcl-6, and c-MYC genes. Immunohistochemistry and FISH examination confirmed the diagnosis of DLBCL. Subsequently, immunofluorescence showed both IgM and IgG deposits in the signet ring-like lymphocytes. After confirming the diagnosis, the patient received four courses of CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisolone) chemotherapy in a specialist hospital and achieved partial remission; however, she unfortunately died of secondary pneumocystis pneumonia infection 3 months later.

CONCLUSION

Malignant lymphoma with signet ring cell morphology is quite uncommon, and this variant can be a diagnostic pitfall. We emphasise that pathologists should consider lymphoma in the differential diagnosis of malignant breast tumours.

Primary lymphoma of bone presenting as spindle cell neoplasm of the vertebral body: a case report and review of the literature

Spindle cell variant of lymphoma is a very rare but known disease entity that can mimic a sarcoma. Diagnosis can be even more challenging if the only site of the disease is in the bone. We report a case of primary lymphoma of bone with spindle cell morphology which was successfully treated with a combination of surgery, chemotherapy, and radiotherapy.

Histiocytic/Dendritic Cell Transformation of B-Cell Neoplasms: Pathologic Evidence of Lineage Conversion in Differentiated Hematolymphoid Malignancies

B-cell lymphomas, such as low-grade follicular lymphoma and chronic lymphocytic leukemia/small lymphocytic lymphoma, can transform to histiocytic/dendritic cell sarcoma (H/DS) in rare cases. The diagnosis of this unconventional neoplastic evolution relies on a combination of immunophenotypic analysis and genotypic studies. A genotype identical to that of the primary B-cell neoplasm in a secondary neoplasm with H/DS immunophenotype supports the lineage conversion to H/DS. Putative mechanisms for this unusual phenomenon include dedifferentiation, common immature progenitor, and transdifferentiation models, the latter of which is suggested by clinical laboratory data at the present time. Elucidation of the molecular mechanisms governing this lineage conversion may facilitate the understanding of carcinogenesis of not only hematopoietic but also nonhematolymphoid neoplasms. The clinical outcome of secondary H/DS is dismal, as observed in sporadic cases, and the optimal treatment remains to be determined.

A spindle cell variant of diffuse large B-cell lymphoma is characterized by T-cell/myofibrohistio-rich stromal alterations: analysis of 10 cases and a review of the literature

Spindle-shaped diffuse large B-cell lymphoma (Sp-DLBCL) has been recognized as a rare morphologic variant of DLBCL. However, the biological processes that contribute to the specific features of Sp-DLBCL remain poorly understood. In this study, a combined immunophenotypic and genetic analysis was performed in 10 Sp-DLBCL. First, we investigated several unique markers for anaplasia (CD30, ALK, CD68, and EBER-ISH), mesenchyma (SMA, desmin, and vimentin), and B-cell differentiation (CD10, BCL6, and MUM1). We also performed conventional cytogenetic and fluorescence in situ hybridization studies to look for common chromosomal break points (BCL2, BCL6, and MYC). We found that most Sp-DLBCLs were germinal center B cell-like and that none had any other specific phenotypes or any karyotypic abnormalities. Instead, T cells, CD68-positive macrophages and SMA-positive myofibroblasts were significantly increased in Sp-DLBCL when compared with conventional GCB origin DLBCL cases (n = 10) (P = 0.012, P < 0.001, and P < 0.0001, respectively). To further characterize Sp-DLBCL, we next compared the expression of fibroblast growth factor 2 (FGF2) and transforming growth factor-β1 (TGFβ1) between the two types of DLBCL. Finally, we confirmed that the number of FGF2- and TGFβ1-positive stromal cells was markedly increased in Sp-DLBCL and that the difference between these and conventional GCB origin DLBCLs was significant (P < 0.0001 and P = 0.0017, respectively). Thus, T-cell/myofibrohistio-rich stromal alterations in Sp-DLBCL, especially those mediated by TGFβ1 and FGF2, may play a role in the transition of lymphoma cells into those with spindle-shaped features.

Primary hepatic lymphoma with spindle cell components: a case report

Diffuse large B-cell lymphoma (DLBCL) with spindle cell components is extremely rare and often misdiagnosed as carcinoma or sarcoma. Here, we present a case of primary DLBCL with spindle cell components arising in the liver, for which a preoperative diagnosis by needle biopsies was unsuccessful. The patient was a 70-year-old man with a continuous cough. Thoracic computed tomography incidentally detected a mass of 5 cm in diameter in his liver. The initial and second needle biopsies from the liver mass were pathologically diagnosed as suspicious for sarcomatoid hepatocellular carcinoma. He underwent an extended left hepatectomy. Histological examination revealed a diffuse or epithelioid arrangement of round and polygonal cells, mixed with the fascicles of spindle-shaped cells. Immunohistochemically, all the morphological types of tumor cells showed positive reactions for a lymphocytic marker (CD45RB) and B-cell markers (CD20 and CD79a). Double-immunostaining revealed that the spindle-shaped tumor cells expressed CD20, but never expressed alpha-smooth muscle actin. Malignant lymphoma with a spindle cell morphology is quite uncommon, and this variant can be a diagnostic pitfall, especially in tiny biopsy specimens. We emphasize that pathologists should be reminded of lymphoma as a differential diagnosis of spindle cell tumors.

Sarcomatoid variant of B-cell lymphoma of the uterine cervix

Malignant lymphomas with a prominent spindle-cell or sarcomatoid pattern are unusual tumors typically of T- or null-cell phenotypes. We encountered a case of a 32-year-old woman who presented with a 3-week history of excessive menstrual bleeding, left lower-quadrant pain, and weight loss. A mass involving the uterine cervix and right parametrium was detected on pelvic examination and imaging studies. A diagnosis of diffuse large B-cell lymphoma with a spindle-cell pattern was made with immunohistochemical and gene rearrangement studies on endocervical curettage and parametrial core biopsy specimens. After chemotherapy and radiation therapy, the patient was in clinical and radiological remission 10 months after diagnosis. To our knowledge, this is the first sarcomatoid B-cell lymphoma presenting in the uterine cervix. Awareness of the spindle-cell pattern of diffuse large B-cell lymphoma and its possible presentation in extranodal sites such as the uterine cervix should prevent potential misdiagnosis.

Diffuse large B-cell lymphoma: one or more entities? Present controversies and possible tools for its subclassification

Diffuse large B-cell lymphoma (DLBCL) is the commonest type of lymphoid tumour world-wide. This category was included both in the REAL and WHO Classification aiming to lump together all malignant lymphomas characterized by the large size of the neoplastic cells, B-cell derivation, aggressive clinical presentation, and the need for highly effective chemotherapy regimens. These tumours are detected as primary or secondary forms both at the nodal and extranodal levels, in immunocompetent hosts as well as in patients with different types of immunosuppression. They display a significant variability in terms of cell morphology and clinical findings, which justifies the identification of variants and subtypes. Among the latter, the primary mediastinal one does actually correspond to a distinct clinicopathological entity. Immunophenotypic, tissue microarray and molecular studies underline the extreme heterogeneity of DLBCLs and suggest a subclassification of the tumour, based on the identification of different pathogenic pathways, which might have much greater relevance than pure morphology for precise prognostic previsions and adoption of ad hoc therapies. The more recent acquisitions on the pathobiology of DLBCLs are reviewed in the light of the authors' experience, aiming to contribute to the existing debate on the topic.

Histological and immunohistochemical characterization of extranodal diffuse large-cell lymphomas with prominent spindle cell features

AIMS

To describe five cases of diffuse large-cell lymphoma with prominent spindle cell components involving skin, nasal-ocular mucosa, and soft tissue. Because of the spindle cell morphology, such cases must be differentiated from true sarcomas arising in or metastasizing to soft tissue, skin, bone, lymph node, or other organs and sites.

METHODS AND RESULTS

Formalin-fixed paraffin-embedded archival tissue from five consultation cases of diffuse large-cell lymphoma with prominent spindle cell features involving the skin, nasal-ocular mucosa, and soft tissue in three male and two female patients was studied by histology and immunohistochemistry. Clinicopathological findings were also reviewed for all the patients. By morphology, initial evaluation of the cases suggested spindle cell sarcoma in two cases, inflammatory pseudotumour in one case, large-cell lymphoma in another case, and one case was considered suspicious for malignant lymphoma. Immunohistochemistry demonstrated a B-cell lineage in four of the spindle cell lesions, with a diagnosis of primary cutaneous CD30+ anaplastic large cell lymphoma made for the fifth case. Four of five cases also showed actin reactivity.

CONCLUSIONS

Although extremely rare, lymphomas with prominent spindle cell morphology can be encountered in daily surgical pathology practice, and should be included in the differential diagnosis of spindle cell lesions in skin and soft tissue. The observed actin reactivity in four of the five spindle cell lymphomas may lead to a misdiagnosis of leiomyosarcoma if lymphoid markers are not included in the immunohistochemical panel.