Primary bone lymphoma

Diffuse large B-cell lymphoma with clear cell morphology - a close mimic of clear cell carcinoma: A case report

RATIONALE

In this case, the tumor cells were epithelioid, with translucent cytoplasm, well-defined cell borders, moderate size, rounded or ovoid nuclei, and small nucleoli visible. Based on this morphological feature, we first considered clear cell carcinoma, but the epithelial-related immunohistochemical results don't support the diagnosis. Ultimately, based on lymphoma-associated immunohistochemical results and gene rearrangement assays, the final diagnosis of a clear cell variant of DLBCL. Therefore, clinicians and pathologists are reminded that DLBCL with clear cell morphology is rare.

PATIENT CONCERNS

A case of a 44-year-old patient who presented with a 1-year's history of an oral tumor that had recently increased in size. Computed tomography (CT) showed an osteolytic lesion with soft tissue density in the right body of mandible with bone destruction in the cortical plates on both buccal and lingual sides.Test results: Immunohistochemistry include vimentin, LCA, CD10, CD20, CD38, B-cell lymphoma (Bcl)-2, multiple myeloma oncogene (MUC)-1, CD79a were strongly expressed, while the tissue was negative for the rest of epithelium and other mesenchymal antibodies. Detection of Ig and TCR gene arrangements showing the presence of B-cell monoclonal rearrangement (DH7-JH) in the tumor.

DIAGNOSIS

The final diagnosis was germinal center B cell-like (GCB) diffuse large B lymphoma of clear cell type.

INTERVENTIONS

The patient was treated with chemotherapy.

OUTCOMES

The patient was undergoing chemotherapy and has been followed up for over 1 year.

LESSONS

Diffuse large B-cell lymphoma with clear cell morphology is a rare tumor, and its diagnosis mainly relies on pathological findings, immunohistochemistry, gene rearrangement.

Neoplastic and Non-neoplastic Bone Lesions of the Knee

Numerous anatomical variants are described around the knee, many of which look like bony lesions, so it is important to know them to avoid unnecessary complementary tests and inadequate management. Likewise, several alterations in relation to normal development can also simulate bone lesions.However, numerous pathologic processes frequently affect the knee, including traumatic, inflammatory, infectious, and tumor pathology. Many of these entities show typical radiologic features that facilitate their diagnosis. In other cases, a correct differential diagnosis is necessary for proper clinical management.Despite the availability of increasingly advanced imaging techniques, plain radiography is still the technique of choice in the initial study of many of these pathologies. This article reviews the radiologic characteristics of tumor and nontumor lesions that may appear around the knee to make a correct diagnosis and avoid unnecessary complementary radiologic examinations and inadequate clinical management.

Follicular Lymphoma Presenting With Symptomatic Bone Involvement: A Clinicopathologic and Molecular Analysis of 16 Cases

Primary bone lymphoma (PBL) is rare and mostly represented by diffuse large B-cell lymphomas (DLBCL). Follicular lymphoma (FL), albeit commonly disseminating to the bone marrow, rarely presents primarily as bone lesions. Here, we studied 16 patients (12 men:4 women, median age 60 years) who presented with bone pain and/or skeletal radiologic abnormalities revealing bone FL. Lesions were multifocal in 11 patients (spine ± appendicular skeleton), and unifocal in 5 patients (femoral, tibial, or vertebral). An infiltrate of centrocytes and centroblasts (CD20+ CD5- CD10+ BCL2+ BCL6+) with abundant reactive T cells and an increased reticulin fibrosis massively replaced the marrow spaces between preserved bone trabeculae. The pattern was diffuse ± nodular, often with paratrabecular reinforcement and/or peripheral paratrabecular extension. Ki-67 was usually <15%. Two cases had necrosis. BCL2 rearrangement was demonstrated in 14 of 14 evaluable cases (with concomitant BCL6 rearrangement in one). High-throughput sequencing revealed BCL2, KMT2D, and TNFRSF14 to be the most frequently mutated genes. After staging, 5 qualified for PBL (3 limited stage) and 11 had stage IV systemic FL. All patients received rituximab ± polychemotherapy as firstline treatment, and 7 received local therapy (6 radiotherapy and 2 surgery). Three patients experienced transformation to DLBCL. At the last follow-up (15/16, median 48 months), 11 patients achieved complete remission, including all cases with PBL and most patients with limited extraosseous disease (3-year progression-free survival 71%). One patient died of unrelated cause (3-year overall survival 91%). FL may manifest as a localized or polyostotic bone disease. A minority represent PBL, whereas most reveal systemic disease.

Comparison of the Effect of Chemoradiotherapy and Chemotherapy on the Survival of Patients with Primary Diffuse Large B-Cell Lymphoma of the Spine: A SEER-Based Study

OBJECTIVE

The role of radiotherapy in primary spinal diffuse large B-cell lymphoma (PB-DLBCL) remains controversial. This study explored the effects of chemoradiotherapy and chemotherapy alone on the survival of patients with PB-DLBCL and established an instructive nomogram.

METHODS

Survival analysis using the Kaplan-Meier method and log-rank test was performed for patients diagnosed with PB-DLBCL from 1983 to 2016, identified in the Surveillance Epidemiology and End Results database. The Cox regression model was used to analyze the effects of each variable on the overall survival (OS) and construct a nomogram for predicting OS in patients.

RESULTS

Overall, 873 patients with PB-DLBCL were included. The patients were divided into the 1983-2001 (227 [26%]) and 2002-2016 (646 [74%]) groups. The 5-and 10-year OS rates of patients with PB-DLBCL in the 2002-2016 group were 62.8% and 49.9%, respectively. The results of the multivariate Cox regression analysis in the 2002-2016 group showed that age, stage, marriage, and treatment strategy were independent prognostic factors. Kaplan-Meier analysis showed that the OS of patients who underwent chemoradiotherapy from 2002 to 2016 was significantly better than that of patients treated with chemotherapy alone. Further subgroup analysis of patients with different stages of DLBCL and at different ages showed that chemoradiotherapy had a better prognosis than chemotherapy alone in stages I-II and age >60 years, whereas the advantages of chemoradiotherapy were not reflected in stages III-IV and age <60 years.

CONCLUSIONS

Chemoradiotherapy improves the OS of patients with PB-DLBCL who are aged >60 years or have stage I-II disease. The nomograms established in this study can help clinicians determine prognosis and select treatment strategies.

Role of 18F-fluorodeoxyglucose PET/computed tomography in the diagnosis and treatment response assessment of primary bone lymphoma

OBJECTIVE

Primary bone lymphoma (PBL) is a rare type of extranodal lymphoma, and the clinical application value of 18F-fluorodeoxyglucose PET/computed tomography ( 18 F-FDG PET/CT) in PBL has not been fully evaluated. This study aimed to determine the imaging characteristics of PBL and investigate the value of 18 F-FDG PET/CT parameters.

METHODS

A total of 25 patients with PBL who underwent PET/CT examination before treatment were included in this study. The clinicopathological parameters and PET/CT parameters were analyzed.

RESULTS

Among the 25 patients, 7 patients had single lesions, 15 patients had nonsingle lesions (≥2) and 3 patients had diffuse distribution in the medullary cavity. The bone destruction types included osteolytic, osteogenic, normal density, mixed lytic and osteogenic. All patients showed increased FDG uptake, and the CT detection rate was 88%. Five patients underwent PET/CT assessment mid-treatment, and when assessed using the Deauville five-point scale, four patients were PET-negative and one patient was PET-positive. There were two PET-positive and three PET-negative patients when assessed using the Δ maximum standardized uptake value (SUV max ) method. Six patients underwent PET/CT imaging at the end of treatment. When assessed using the Deauville five-point scale, five patients (83%) were PET-negative and one patient (17%) was PET-positive. The same results were obtained when evaluated by the ΔSUV max method.

CONCLUSION

PET/CT plays a substantial role in the diagnosis and treatment efficacy evaluation of PBL, and it should be recognized by clinicians and radiologists. Changes in metabolic parameters such as SUV, metabolic tumor volume and total lesion glycolysis have considerable potential for application in PBL diagnostics and treatment efficacy evaluation.

Primary Bone Lymphoma: A Review of the Literature with Emphasis on Histopathology and Histogenesis

Primary bone lymphoma (PBL) is a rare neoplasm of malignant lymphoid cells presenting with one or more bone lesions without nodal or other extranodal involvement. It accounts for approximately 1% of all lymphomas and 7% of malignant primary bone tumors. Diffuse large B-cell lymphoma (DLBCL), not otherwise specified (NOS) represents the predominant histological type and constitutes over 80% of all cases. PBL may occur at all ages with a typical diagnosis age of 45–60 years and a slight male predominance. Local bone pain, soft tissue edema, palpable mass and pathological fracture are the most common clinical features. Diagnosis of the disease, which is frequently delayed due to its non-specific clinical presentation, is based on the combination of clinical examination and imaging studies and confirmed by combined histopathological and immunohistochemical examination. PBL can develop in any part of the skeleton, although it occurs most commonly in the femur, humerus, tibia, spine and pelvis. The imaging appearance of PBL is highly variable and unspecific. In terms of the cell-of-origin, most cases of primary bone DLBCL (PB-DLBCL), NOS belong to the germinal center B-cell-like subtype and specifically originate from germinal center centrocytes. PB-DLBCL, NOS has been considered a distinct clinical entity based on its particular prognosis, histogenesis, gene expression and mutational profile and miRNA signature. PBL carries a favorable prognosis, especially when treated with combined chemoradiotherapy.

Nomogram-Based Prediction of Overall and Cancer-Specific Survival in Patients with Primary Bone Diffuse Large B-Cell Lymphoma: A Population-Based Study

Background

Primary bone diffuse large B-cell lymphoma (PD-DLBCL) accounts for more than 80% of primary bone lymphoma. We created two nomograms to predict overall survival (OS) and cancer-specific survival (CSS) in patients with PD-DLBCL for this rare disease.

Methods

In total, 891 patients diagnosed with PB-DLBCL between 2007 and 2016 were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. Univariate and multivariate Cox analyses were performed to explore independent prognostic factors and create nomograms for OS and CSS. The area under the curve (AUC), the calibration curve, decision curve analysis (DCA), and Kaplan-Meier (K-M) curve analysis were used to evaluate the nomograms.

Results

Four variables were identified as independent prognostic factors for OS, and three variables were identified as independent prognostic factors for CSS. The receiver operating characteristic (ROC) curves demonstrated the strong discriminatory power of the nomograms. The calibration and DCA curves showed that the nomograms had a satisfactory ability to predict OS and CSS. The K-M curves showed that age, gender, primary site, chemotherapy, and tumor stage affected patient survival.

Conclusions

In patients with PD-DLBCL, age, race, primary site, and chemotherapy affected OS, while age, race, and chemotherapy affected CSS. The two nomograms created based on the aforementioned variables provided more accurate individual survival predictions for PD-DLBCL patients and can help physicians make appropriate clinical decisions.

Burkitt's lymphoma of medial part of clavicle: Case report of unusual localization

INTRODUCTION

Burkitt lymphoma is a form of non-Hodgkin's lymphoma in which cancer starts in immune cells called B-cells. Recognized as a fast-growing human tumor, it is considered as a medical emergency requiring immediate diagnostic and therapeutic intervention. However, intensive chemotherapy can achieve long-term survival in more than half the people with Burkitt lymphoma.

CASE REPORT

We report a case of Burkitt's lymphoma of medial part of clavicle was diagnosed in a 60 years year-old man and review the literature concerning the clinical features, radiological appearance, histopathological findings and treatment options.

DISCUSSION

Clinical course of Burkitt lymphoma is aggressive and rapid, commonly occurs in children and young adults with frequent involvement of Bone Marrow, associated with impaired immunity and is rapidly fatal if left untreated, early diagnosis can be life saving for Burkitt lymphoma. As per the literature available this is the second case of Burkitt's lymphoma presenting primarily in medial part of clavicle.

A rare presentation of primary lymphoma of bone with aneurysmal bone cyst-like changes

Primary lymphoma of bone occurs rarely in children with variable imaging findings ranging from a lytic lesion to an aggressive permeative lesion. We detail a case report with review of literature of a 14-year-old boy with a rare presentation of primary lymphoma of bone with aneurysmal bone cyst-like changes. The lesion was surgically excised as management for aneurysmal bone cyst but histopathological examination of the excised tissue revealed a non-Hodgkin's type of lymphoma. This unique type of aneurysmal bone cyst-like presentation has not been well characterised until now in the imaging spectrum of primary lymphoma of bone. Clinicians need to be aware of this uncommon presentation for early intervention and appropriate management of this malignancy in children.

Primary bone lymphoma: Clinical presentation and therapeutic considerations

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Primary lymphoma of bone is a rare entity with unspecific symptoms.

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Typical radiology is a large soft-tissue tumor around non-destructed bone.

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Treatment is based on systemic chemotherapy.

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Chemotherapy seems to produce a better outcome than radiotherapy alone.

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Positiv factors: age<60 y, solitary lesion, low LDH, favourable ECOG and IPI scores.

Background

Primary lymphoma of bone (PBL) is a rare entity. Due to unspecific clinical signs and equivocal radiographs diagnosis may be delayed. This retrospective report of 109 PBL cases demonstrates typical aspects of the lesion. Treatment and prognostic factors are evaluated.

Methods

Retrospectively patient records were reviewed. All patients were followed for evidence of local or distant recurrence. Overall survival (OS) was used as clinical outcome.

Results

The median age of the 109 patients was 62.8 years. The most common symptoms were pain (76%), swelling (29%), neurologic symptoms and pathological fracture (16% each). Mean duration of symptoms was 8 months (0–197 months).

19% of patients had indolent NHL subtypes, 72% aggressive NHL subtypes and 7% cases Hodgkin disease. Cyclophosphamid, doxorubicin, vincristine and prednisone (CHOP) or CHOP plus rituximab (RCHOP) were given in 88 (81%) of patients. Radiotherapy was delivered in 67 (61%) of cases. 51 (47%) patients received both. Surgical interventions were restricted to cases with complications as fractures.

The 5-year OS was 66%. The 5-year OS was 66%. In the subgroup of 78 patients with aggressive NHL subtype there was a highly significant benefit for chemotherapy or chemotherapy and radiation in comparison to no treatment or radiation alone. Raised LDH, age, IPI and ECOG performance were prognostic factors. In multivariate analysis, age and raised LDH levels only kept significance.

Conclusions

In our series of primary bone lymphoma, chemotherapy resulted in a better outcome than Radiotherapy alone. Long-term survival is based on the stage of the disease, favoring younger (<60 years) patients with solitary bone lesions, low level of LDH and favourable ECOG performance status and IPI scores.

Primary lymphoma of the distal radius of a child: imaging features

Primary lymphoma of bone (PLB) is a rare entity, defined as a lymphoma confined to the bone without evidence of systemic involvement. The disease commonly affects middle-aged to elderly population and it accounts for less than 1% of all malignant lymphomas. We present a case of a 10-year-old child affected by PLB of the forearm and the frontal bone. Characteristic imaging features of PLB and the main differential diagnosis were discussed.

A Case of Extranodal Metastasis of Primary Bone Lymphoma in the Lower Extremity

Primary bone lymphoma is a rare disease, accounting for less than 5% of all extranodal lymphoma. Although the femur is cited as being the most common site, primary bone lymphoma is rare, accounting for less than 1% of all non-Hodgkin's lymphoma. Herein we present a case of diffuse B-cell-type malignant lymphoma manifested as a large soft-tissue mass of the leg, via metastasis of primary non-Hodgkin's lymphoma of the femur, which went untreated. We highlight the advantages of various imaging modalities used throughout the process of diagnosis and treatment because accurate and early diagnosis are essential. This case gives us a unique opportunity to witness the rapid progression of metastasis and an atypical location.

Non-Hodgkin's lymphoma and atypical neck pain: A case report

Neck pain is a common reason for seeking medical attention. It affects at least 15% of the labor force and up to 40% of individuals whose occupation is hazardous. On the other hand, primary bone lymphoma is a very rare disease (less than 1% of all malignant bone tumors), and the relationship between the 2 has rarely been mentioned. We report the case of a patient who had a 1-month history of neck pain. The main symptom was pain on palpation of C2-C6 cervical spinous processes and contracture of the trapezius muscle that did not cease with conventional treatment. Imaging studies indicated an abnormality. He underwent surgery and the results of vertebral biopsy were compatible with diffuse large B-cell lymphoma. He was treated with radiotherapy with a good outcome.

ALK positive Anaplastic Large Cell Lymphoma of the Thoracic Spine

Primary bone lymphoma (PBL) is an uncommon extra nodal disease that represents about 1-3% of lymphoma cases. Imaging findings are variable and non-specific. Computed tomography may demonstrate lytic lesions with sequestra and periosteal reaction. On magnetic resonance imaging, lesions are T1WI hypointense and T2WI hyperintense, related to peritumoral edema or bone marrow replacement. Rarely lesions may have associated fibrosis and show a more hypointense signal pattern on T2WI. After administration of contrast, PBL tends to enhance avidly. We present a case of a 24 years old African American female patient with history of back pain. Initial imaging examinations showed lesions involving the T12 and T11 vertebral bodies with initial negative biopsy results. One month later, the patient returned with worsening back pain, and the follow up studies depicted collapse of the T12 vertebral body. A diagnosis of anaplastic large cell lymphoma in T12 was made. A brief review of the literature, imaging and pathological findings, and treatment options are also discussed.

Clinical characteristics and prognostic factors of bone lymphomas: focus on the clinical significance of multifocal bone involvement by primary bone large B-cell lymphomas

Background

Malignant bone lymphoma can be classified as primary (PBL) or secondary (SBL) bone lymphoma. However, the clinico-pathological characteristics and prognostic factors of PBL versus SBL have not yet been well defined. Whether lymphoma with multifocal bone involvement should be considered as stage IV PBL or SBL still remain controversial throughout the literature.

Methods

In this study, we retrospectively reviewed 127 patients with bone lymphoma diagnosed from1998 to 2013 at the Moffitt Cancer Center. Patients were classified as PBL (81 cases) and SBL (46 cases) using the 2013 WHO Classification of Bone/Soft Tissue Tumors and PBL patients were further subdivided into: 1) PBL with unifocal bone disease (uPBL, 46 cases), 2) PBL with multifocal bone involvement (mPBL, 35 cases). Patient characteristics, survival, and prognostic factors were analyzed.

Results

Diffuse large B-cell lymphoma (DLBCL) was the most common histological subtype in all three groups (37/46 of uPBL, 23/35 of mPBL, 23/46 of SBL). B symptoms, lymph node involvement, and bone marrow involvement were found to be more common in mPB-DLBCL and SB-DLBCL groups than in the uPB-DLBCL group. Femur was found to be the most common affected site in uPB-DLBCL patients, while spine was most commonly involved in the other two groups. Survival analysis indicated that uPBL-DLBCL patients had a significantly better progression-free survival (PFS) and overall survival (OS) than those in the other two groups (P < 0.05). We also found by univariate analysis that multifocality, and stage IV were significantly poor prognostic factors for both PFS and OS in PBL patients. Using multivariate analysis, multifocality remained an independent prognostic factor for both PFS and OS (P = 0.0117, RR: 3.789, 95% CI: 1.275-11.256).

Conclusion

Overall, our results suggest that mPBL is more similar to SBL in characteristics and survival rather than uPBL, and thus should be better classified and treated as SBL.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2407-14-900) contains supplementary material, which is available to authorized users.

Primary diffuse large B-cell lymphoma associated with chronic osteomyelitis of the knee

Diffuse large B-cell lymphoma (DLBCL) associated with chronic inflammation is a recently adopted category of DLBCL, which describes an aggressive B-cell lymphoma raised in the setting of non-immune chronic inflammation. Primary presentation of this subtype of DLBCL in bone is extremely rare. Here, we present the case of a 27 year old woman with DLBCL of the right distal femur, identified after a three-year history of chronic osteomyelitis. In this report, we describe the clinical and histopathologic features of this unusual presentation of DLBCL and discuss aspects relevant to diagnosis and treatment of this entity.

Unusual primary osseous Hodgkin's lymphoma: A case report

Hodgkin's lymphoma (HL) is one of the few adult malignancies that most frequently presents with a progressive, painless enlargement of the peripheral lymph nodes. A primary osseous presentation of HL, without lymph node involvement, is extremely rare. The present study describes a case of primary multifocal osseous HL in a 22-year-old female. The patient presented with pain in the lumbar-sacral-pelvic area and a prolonged fever. Pathological examination led to a diagnosis of primary multifocal osseous lymphoma, and the patient was subsequently prescribed a course of Adriamycin, bleomycin, vinblastine and dacarbazine (ABVD) chemotherapy. Following this, the patient recovered with no pain or fever, and computed tomography identified no further progression. The clinical, radiological and histological features of HL are similar to those of other medical conditions, such as tuberculosis and eosinophilic granuloma. Furthermore, in rare cases, HL may even occur in combination with multiple myeloma. This makes it difficult to diagnose the condition, which often leads to a delay in treatment. Clinicians should not ignore HL when it manifests in the unusual primary osseous form.

Primary bone lymphoplasmacytic lymphoma presenting with spinal cord compression: a case report

Primary bone lymphoma is a rare disease, and the main pathological type is diffuse large B-cell lymphoma. The occurrence of follicular, marginal zone and lymphoplasmacytic lymphomas is rare. Vertebras are also sites that can be affected, and spinal cord compression is reported in 14% of patients with vertebral involvement. However, there is no report on primary vertebral lymphoplasmacytic lymphoma with spinal cord compression. The present report presents one case of primary vertebral lymphoplasmacytic lymphoma with spinal cord compression and increased serum and urine λ light chain, without an elevated heavy chain of immunoglobulin.

Conflict of interest:None declared.

Prognostic factors and treatment efficacy in patients with primary diffuse large B-cell lymphoma of the bone: single institute experience over 11 years

OBJECTIVE

Primary bone lymphoma is a rare disorder, accounting for less than 1% of all cases of malignant lymphoma. Primary bony diffuse large B-cell lymphoma (PBDLBCL) is the most common histological type. In our study, a favorable response and lower risk of emergent surgery were observed following the administration of systemic chemotherapy with or without rituximab.

METHODS

Patients diagnosed with malignant lymphoma at our hospital between 2000 and 2011 were evaluated for PBDLBCL. Pertinent data, including the clinical presentation, histological type, treatment modalities, long-term outcome, survival curve and prognostic factors, were analyzed.

RESULTS

Twenty-four patients with a median age of 63 years were diagnosed with PBDLBCL. A complete response (CR) was achieved in 58.4% (n=14) of the patients. With treatment of the disease, nine of 10 patients with initially impending pathological bone fractures ultimately did not undergo surgery. The median follow-up duration was 48 months. Two patients experienced disease relapse. In a Kaplan-Meier analysis, the 5-year overall survival (OS) and disease-free survival (DFS) rates were 66.7% and 77.8%, respectively. In the univariate analyses, the significantly favorable prognostic factors for OS were an International Prognostic Index (IPI) score of <3, an age of ≤60 years, a performance status with an Eastern Cooperative Oncology (ECOG) score of <2, a CR and chemotherapy ≥6 cycles. For DFS, a CR was the only favorable factor. In the multivariate analysis, a CR was the only independent factor for both OS and DFS.

CONCLUSION

Our study confirms the good prognosis of this rare disorder. Once a CR is achieved, even elderly patients may exhibit long-term survival, possibly obviating the need for surgery for less severe bone lesions.

Case report and review of primary bone diffuse large B-cell lymphoma involving the calcaneus

Primary bone lymphoma from diffuse large B-cell lymphoma is a very rare condition, especially in the foot. In the present case report, a 23-year-old female patient presented with long-term pain along the lateral aspect of her right calcaneus. Ancillary magnetic resonance imaging revealed a radiolucent bone tumor in the calcaneus. Computed tomography-guided biopsy of the bone was completed and revealed chronic inflammation with hematopoietic elements. The patient continued to have pain and limitation in her daily activities after the biopsy. The patient underwent surgical excision and curettage by the senior author. Pathologic examination revealed that the lesion was consistent with diffuse, large, B-cell lymphoma, stage IAE. The lesion appeared to have been completely excised at surgery, and the patient underwent 3 cycles of chemotherapy and 15 radiotherapy sessions to the calcaneus. At the last follow-up visit, the patient had been disease free for 5 years. To our knowledge, this is the first case report of primary bone, diffuse, large B-cell lymphoma of the calcaneus to be treated with a combination of surgical excision, chemotherapy, and radiotherapy.

Unusual primary osseous Hodgkin lymphoma in rib with associated soft tissue mass: a case report and review of literature

VIRTUAL SLIDES

Hodgkin lymphoma (HL) typically presents as nodal lesion and may involve extranodal sites during the progression of the disease. Primary osseous HL without any lymph node association is extremely rare and only a few such cases have been described in the literature. We present a case of unusual primary HL in rib occurring in a middle-aged female patient. Computed tomography (CT) scan revealed an osteolytic lesion was located at the right second rib and was associated with a large soft tissue mass. There was no regional lymph node involvement. CT scan of neck and abdomen was performed and showed no pathologic findings, particularly no lymphadenopathy and organomegaly could be observed. Histologically, typical binucleated Reed-Sternberg (RS) cells and lacunar cells were scattered in the background of reactive inflammation with infiltration of lymphocytes, histiocytes and eosinophilic granulocytes. By immunohistochemistry, RS cells and lacunar cells were positive for CD15 and CD30 with typical membrane and paranuclear dot-like staining pattern. However, these cells were negative for Epstein-Barr virus detection by in situ hybridization. A diagnosis of primary osseous HL was made. The patient received systemic chemotherapy and local radiotherapy, and was on regular follow-up for 24 months. There was no sign of recurrence of tumor and lymph node or bone marrow involvement. Because there is a possibility of secondary bone involvement by systemic HL, strict histological analysis and thorough radiographic examination are suggested to be necessary for accurately diagnosing this tumor when it presents as a solitary bone lesion.

Small Round Cell Tumors of Bone

Diagnosing small round cell tumors (SCRTs) can be a difficult task for pathologists due to overlapping clinicopathologic features. This review highlights the clinical, radiographic, histologic, immunohistochemical, and genetic features of the most common SRCTs involving bone with an emphasis on differential diagnosis. SRCTs are a heterogeneous group of neoplasms characterized by poorly differentiated cells with small, blue, round nuclei and scant cytoplasm. They can occur as primary tumors in bone or soft tissue.