Primary extranodal diffuse large B-cell lymphomas: Many sites, many entities? Clinico-pathological, immunohistochemical and cytogenetic study of 106 cases

Transformed gastric mucosa-associated lymphoid tissue lymphoma originating in the colon and developing metachronously after Helicobacter pylori eradication: A case report

BACKGROUND

Helicobacter pylori (H. pylori) eradication treatment for primary gastric mucosa-associated lymphoid tissue (MALT) lymphoma has already been established. However, t (11;18) (q21;q21)/API2-MALT1 translocation-positive lesions are a type of primary gastric MALT lymphoma in which a response to eradication treatment is difficult to achieve. In addition, trisomy 18 may be associated with diffuse large B-cell lymphoma (DLBCL) transformation of gastric MALT lymphoma.

CASE SUMMARY

A 66-year-old man was diagnosed with MALT lymphoma in the ascending colon by colonoscopy and biopsy. Two years later, esophagogastroduodenoscopy revealed chronic atrophic gastritis that was positive for H. pylori, and eradication treatment was administered. Two years and nine months later (at the age of 70), a new ulcerative lesion suggestive of MALT lymphoma appeared in the gastric body, and six months later, a similar lesion was also found in the fundus. One year later (4 years and 3 months after H. pylori eradication), at the age of 72, the lesion in the gastric body had become deeper and had propagated. A biopsy revealed a pathological diagnosis of DLBCL. Both MALT lymphoma lesions in the ascending colon and DLBCL lesions in the stomach were positive for the t (11;18) (q21;q21)/API2-MALT1 translocation, and trisomy 18q21 was also detected. After 6 courses of R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone) chemotherapy, all of the above lesions disappeared [complete remission (CR)], and CR has been maintained for more than 3 years. In addition, both the colonic and gastric lesions were proven to have the same clonality.

CONCLUSION

Because the patient had a MALT1 translocation with trisomy 18q21, it was thought that this gastric MALT lymphoma developed independently of H. pylori infection and progressed.

Clinicopathological differences in MYC and BCL2 protein expression between primary extranodal and nodal diffuse large B-cell lymphoma

Diffuse large B-cell lymphoma (DLBCL) exhibits clinical, genetic, and immunohistochemical heterogeneity. However, the differences between primary extranodal or nodal DLBCL and double-expressor lymphoma (DEL), which is characterized by high MYC and BCL2 expression, remain unclear. This study aimed to elucidate the clinicopathological features, response to therapy, and clinical outcomes of primary extranodal (n=61) and nodal (n=128) DLBCL. Patients with primary nodal DLBCL had higher BCL2 expression than those with extranodal DLBCL (p=0.048), with high MYC expression and DEL as poor prognostic factors. Conversely, in patients with primary extranodal DLBCL, high BCL2 expression, low BCL6 expression, non-germinal center B-cell-like type, and DEL indicated poor prognosis. DEL was significantly associated with progression free survival and overall survival in patients with primary extranodal DLBCL (p=0.014 and p=0.021, respectively) but not in patients with primary nodal DLBCL (p=0.37 and p=0.084, respectively). Our findings highlight primary extranodal DEL as a strong adverse prognostic factor in DLBCL.

Extranodal diffuse large B-cell lymphoma presenting with extensive organ involvement

Extranodal involvement in diffuse large B-cell lymphoma (DLBCL) is defined as disease outside of the lymph nodes and occurs in up to one-third of patients, though multiorgan extranodal involvement is rare. Here, we describe a case of a patient presenting with widely metastatic lesions, including involvement of the lung, parotid gland, breast, pancreas, femur and multiple soft tissue masses, with initial concern for primary breast malignancy. Breast pathology and imaging were consistent with triple-expressor, double-hit stage IV high-grade B-cell lymphoma with extensive extranodal involvement. Extranodal involvement is a poor prognostic factor associated with high rates of treatment failure, and novel therapies targeting CD19 are currently being studied for relapsed and refractory DLBCL. Extranodal disease is a complex entity that can involve virtually any organ system and should be considered for new presentations of malignancy.

Clinico-Pathological, Cytogenetic and Molecular Profiles of Primary Cutaneous Diffuse Large B-Cell Lymphomas

We analyzed the clinico-pathological, cytogenetic and molecular features of 18 Primary Cutaneous Diffuse Large B-Cell Lymphoma (PCDLBCL), and 15 DLBCL secondarily localized to the skin (SCDLBCL), highlighting biologic similarities and differences between the two groups. PCDLBCL were sub classified after histopathological review as PCDLBCL-Leg type (PCDLBCL-LT, 10 cases) and the PCDLBCL-not otherwise specified (PCDLBCL, NOS, 8 cases). Immunohistochemistry for Hans' algorithm markers, BCL2, and MYC was performed. The molecular study included the determination of the cell of origin (COO) by Lymph2Cx assay on Nano string platform, FISH analysis of IgH, BCL2, BCL6, and MYC genes, as well as the mutation analysis of MYD88 gene. At immunohistochemistry, BCL2 and MYC hyper expression was more frequent in LT than in NOS cases and, according to Hans' algorithm, PCDLBCL LT were mostly of the non-GC type (8/10), whereas in PCDLBCL NOS the GC type prevailed (6/8). The determination of COO using Lymph2Cx supported and further confirmed these results. At FISH analysis, all but one LT cases versus 5 out of 8 PCDLBCL NOS showed at least one gene rearrangement among IgH, BCL2, MYC or BCL6. In addition, MYD88 mutations were more frequently present in LT than in NOS subtypes. Interestingly, MYD88- mutated patients were older, with a non-GC phenotype and had worse OS, compared to MYD88 WT cases. Overall, SCDLBCL did not show, at the genetic and expression level, different profiles than PCDLBCL, even if they bear a significantly worse prognosis. At survival analysis, the most important prognostic factors in PCDLBCL patients were age and MYD88 mutation, whereas relapse and high Ki67 expression were relevant in SCDLBCL patients. Our study comprehensively analyzed the clinico-pathological and molecular features of PCDLBCL LT, PCDLBCL-NOS, and SCDLBCL, underlining the differnces among them and the importance of properly identifying these entities at the time of diagnosis.

[Primary pancreatic lymphoma clinically mimicking carcinoma. An important differential diagnostic problem due to the different therapeutic implications]

Primary pancreatic lymphoma is very rare; the most commonly described subtype is diffuse large B-cell lymphoma. Although it is morphologically similar to lymphoproliferative lesions found in other locations, clinically it can mimic an epithelial neoplasm. The differential diagnosis is important due to the different therapeutic implications of each entity. We present a case of primary pancreatic lymphoma in a 77-year-old woman and describe its characteristic features.

High grade non-germinal centre-like diffuse large B-cell lymphoma double expressor presenting as a hydrocoele

A 72-year-old man was referred to our urology outpatient department with a left hemi-scrotal swelling increasing in size over a matter of weeks, initially suspicious for a left hydrocoele. Initial investigation with ultrasound (US) identified a heterogenous enlargement of the left testis and epididymis with a soft tissue mass extending through the inguinal canal. Subsequent CT detected this soft tissue mass to extend along the left gonadal vein to the level of the left renal vein. A biopsy of the retroperitoneal mass confirmed a diagnosis of diffuse large B-cell lymphoma. Immunohistochemical staining further categorised this lymphoma as double expressor but not double hit.Through multidisciplinary team involvement the patient was treated with combination steroids and chemotherapy. Given the scrotal involvement this was considered a sanctuary site for chemotherapy therefore the patient also received radiotherapy to the scrotum. He recovered well following his treatment. This case highlights how early specialist referral can identify rare variants of disease. Essential preoperative imaging with US prior to treating a presumed hydrocoele prevented inappropriate surgical excision. A multidisciplinary team approach improved the patient's outcome and is hoped to have improved his chances of recurrence-free survival.

Treatment of refractory diffuse large B-cell lymphoma by chidamide combined with autologous stem cell transplantation: a case report

Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin's lymphoma, with certain DLBCLs affecting specific anatomic sites, such as primary cutaneous DLBCL, leg type and intravascular large B-cell lymphoma. However, the occurrence of secondary cutaneous involvement in DLBCL while patients are undergoing regular chemotherapy is rare. In this study, we reported a case of refractory diffuse large B-cell lymphoma with cutaneous involvement that achieved complete remission for more than 4 years with epigenetic regulation of chidamide in combination with chemotherapy and autologous hematopoietic stem cell transplantation including a pretreatment regimen containing chidamide.

A Prognostic Model of Gastrointestinal Diffuse Large B Cell Lymphoma

Background

The digestive tract is the most common site of extranodal involvement in diffuse large B cell lymphoma (DLBCL) and its prognostic evaluation is different from that of ordinary DLBCL. Currently, for gastrointestinal lymphoma, in addition to the Ann Arbor staging system, the Lugano and the TNM staging systems are commonly used. However, there is no effective prognostic model to identify poor prognosis in patients with localized gastrointestinal diffuse large B cell lymphoma (GI-DLBCL).

Material/Methods

This study included 82 patients with GI-DLBCL that had a median follow-up of 75 months, and developed a model (HLAMA) with 5 variables: hemoglobin, age, lactate dehydrogenase (LDH), serum albumin, and the maximum intra-abdominal lesion diameter (MIALD). The specific indicators are: HGB <105 g/L (2 points); LDH ≥300 U/L; age ≥75 years, ALB <38 g/L, MIALD ≥4 cm (each scoring 1 point). We also developed a simplified model, which includes only 3 variables (HGB, LDH, and age).

Results

HLAMA model and the simplified model both demonstrated good ability to predict prognosis of patients with GI-DLBCL (P<0.001), performing better than the IPI score as it could distinguish low-risk groups in relatively elderly patients (60–75 years old).

Conclusions

This study established a prognostic model for diffuse large B cell lymphoma of the gastrointestinal tract. Both the HLAMA model and its simplified version are similar to the IPI score, but could be considered better as they can provide a simpler and more accurate prognostic assessment in patients with GI-DLBCL. For patients with localized GI-DLBCL, our model could distinguish high-risk patients.

Case Report: Concurrent Occurrence of Abdominal Double Expressor Lymphoma and Jejunum Follicular Lymphoma

Double expressor lymphoma (DEL), defined as overexpression of BCL2 and MYC, is an aggressive subtype of diffuse large B cell lymphoma (DLBCL). Here we report a case of a 64-year-old female diagnosed with abdominal DEL transformed from jejunum follicular lymphoma (FL). 18F-fluorodeoxyglucose (FDG)-positron emission tomography showed diffuse accumulation of FDG into the peritoneum and small bowel wall. Double balloon-assisted enteroscopy revealed whitish submucosal tumors in the proximal jejunum. Aggregation of atypical lymphocytes positive for CD20, CD79a, and BCL2 was seen in the jejunal biopsy samples. These atypical lymphocytes were monoclonal since cell surface expression of Ig light chains was limited to κ chain by flow-cytometry. Thus, immunohistochemical and flowcytometric analyses data were consistent with FL of the jejunum. Neoplastic lymphocytes obtained from ascites were positive for CD10, CD20, CD79a, BCL2, and BCL6. Fluorescence in situ hybridization (FISH) showed formation of BCL2/IgH fusion gene and extra copies of MYC, the former of which is a characteristic chromosomal abnormality of FL. These genetic alterations and protein expression profiles of ascitic fluid cells were consistent with those of DEL transformed from FL. Given that a significant population of patients with indolent FL of the gastrointestinal tract developed into aggressive DLBCL, it is likely that primary FL of the jejunum transformed into the abdominal aggressive DEL in this case. This case is unique in that concurrent occurrence of FL and DEL was confirmed by immunohistochemical and FISH analyses and that abdominal DEL transformed from jejunal FL was highly suspected.

Downregulation of USP18 reduces tumor-infiltrating activated dendritic cells in extranodal diffuse large B cell lymphoma patients

Extranodal diffuse large B cell lymphoma (EN DLBCL) often leads to poor outcomes, while the underlying mechanism remains unclear. As immune imbalance plays an important role in lymphoma pathogenesis, we hypothesized that immune genes might be involved in the development of EN DLBCL. Ninety-three differentially expressed immune genes (DEIGs) were identified from 1168 differentially expressed genes (DEGs) between tumor tissues of lymph node DLBCL (LN DLBCL) and EN DLBCL patients in TCGA database. Nine prognostic immune genes were further identified from DEIGs by univariate Cox regression analysis. A multivariate predictive model was established based on these prognostic immune genes. Patients were divided into high- and low-risk groups according to the median model-based risk score. Kaplan-Meier survival curves showed that patients in the high-risk group had a shorter survival time than those in the low-risk group (P < 0.001). Ubiquitin-specific peptidase 18 (USP18) was further recognized as the key immune gene in EN DLBCL on the basis of coexpression of differentially expressed transcription factors (DETFs) and prognostic immune genes. USP18 exhibited low expression in EN DLBCL, which was regulated by LIM homeobox 2 (LHX2) (R = 0.497, P < 0.001, positive). The potential pathway downstream of USP18 was the MAPK pathway, identified by gene set variation analysis (GSVA), gene set enrichment analysis (GSEA) and Pearson correlation analysis (R = 0.294, P < 0.05, positive). The "ssGSEA" algorithm and Pearson correlation analysis identified that activated dendritic cells (aDCs) were the cell type mostly associated with USP18 (R = 0.694, P < 0.001, positive), indicating that USP18 participated in DC-modulating immune responses. The correlations among key biomarkers were supported by multiomics database validation. Indeed, the USP18 protein was confirmed to be expressed at lower levels in tumor tissues in patients with EN DLBCL than in those with LN DLBCL by immunohistochemistry. In short, our study illustrated that the downregulation of USP18 was associated with reduced aDC number in the tumor tissues of EN DLBCL patients, indicating that targeting USP18 might serve as a promising therapy.

Optimized workflow for digitalized FISH analysis in pathology

BACKGROUND

Effective workflow management in a diagnostic pathology laboratory is critical to achieve rapid turnover while maintaining high quality. Fluorescence in situ hybridization analysis (FISH) is the preferred technique for detecting single chromosomal aberrations in diagnostic surgical pathology.

MATERIAL AND METHODS

FISH analysis applying a rapid hybridization protocol and using an automated whole-slide fluorescence scanning device (3DHISTECH, Sysmex, Switzerland) were implemented in our workflow. By analyzing 42 diagnostic cases, effects of two different scanning profiles on scanning time, and device memory usage were investigated. Manual signal counting (CaseViewer) and software based signal counting (FISHQuant) were compared.

RESULTS

The two scanning profiles, both including a Z-stack function, differed in their exposure time and digital gain. The "low profile" setting (LP) resulted in a significantly shorter scanning time and lower storage volume compared to the "high profile" (HP) setting, making the LP ideal for routine applications. Both signal counting methods (manual versus software based) provided similar cut-offs on a test-cohort of 13 samples.

CONCLUSION

Scanning FISH slides provides good picture quality, reduces the analysis time and allows easy picture archiving and facilitates remote diagnostics, allowing an effective workflow.

Renal metastases from esophageal cancer and retroperitoneal lymphoma detected via chromosome duplications identified by fluorescence in situ hybridization in urine exfoliated cells: First 2 case reports

RATIONALE

Renal-occupying lesions positive for urine fluorescence in situ hybridization (FISH) are usually considered urothelial carcinomas. Here, we describe 2 cases of renal metastases with chromosome duplications in urine exfoliated cells.

PATIENT SYMPTOMS

Patient 1, a 56-year-old male with a history of esophageal cancer, was admitted to our hospital on May 2017 after presenting with right back pain with microscopic hematuria for 1 month. Magnetic resonance imaging (MRI) showed right renal space-occupying lesions (5.4 cm × 4.6 cm) and multiple enlarged lymph nodes in the right renal hilum and retroperitoneum. The cystoscopy results were negative, and FISH analysis of urine exfoliated cells was positive, indicative of chromosome 3, 7, and 17 amplifications. Patient 2 was a 50-year-old male who was admitted to our hospital on May 2019 with no obvious cause of abdominal pain and abdominal distension (lasting for 7 days), with a serum creatinine level of 844 μmol/L. Patient 2 had no hematuria or fever, and MRI showed left renal inferior and medial space-occupying lesions, and multiple mesenteric nodules at the junction of the left adrenal gland, retroperitoneum, abdomen, and pelvis, which were partially fused. The tumor lesions were approximately 3.1 cm × 2.3 cm in size. The urine FISH results were positive, indicating chromosome 3, 7, and 17 amplifications.

DIAGNOSES

Both patients were diagnosed with renal tumors with unknown pathology.

INTERVENTIONS

Patient 1 underwent laparoscopic resection of the kidney and ureter, and sleeve cystectomy. The postoperative pathological diagnosis was metastatic keratinized squamous cell carcinoma, with squamous cell carcinoma in the right hilar lymph node. Histological FISH of the primary esophageal cancer and renal metastases were consistent with the urine FISH test results. Patient 2 underwent a biopsy of the left renal inferior and retroperitoneal areas, and was diagnosed with diffuse large B-cell lymphoma.

OUTCOMES

Patient 1 survived 6 months after urological surgery. After treating patient 2 with the R-CHOP regimen and kinase inhibitors, his renal function recovered significantly and the mass become undetectable.

LESSONS

Our results imply that FISH-positive renal occupying lesions should be considered as potential renal metastases with chromosome aberrations when making a differential diagnosis.

Hematologic malignancies of the gastrointestinal luminal tract

Hematologic malignancies include several lymphoproliferative and myeloproliferative disorders, many of which are frequently encountered in current health care settings. These malignancies frequently affect the gastrointestinal (GI) tract, either by secondary extranodal or extramedullary extension to the GI tract, or as a primary process arising in the GI tract. In fact, the GI tract may represent the most common extranodal site of involvement in many of them, such as lymphoma. Furthermore, in the current era of improved cancer treatment and advanced transplant procedures with increased survival, it has been quite common to encounter GI involvement by these malignancies through the disease course. Post-transplant lymphoproliferative disorder following kidney transplantation, for example, very commonly involves the GI tract. Other conditions that can involve the GI tract include multiple myeloma, plasmacytoma, myeloid sarcoma, mastocytosis, and Castleman disease. Imaging diagnosis of these malignancies can be challenging, since they are much less common than primary GI cancers and both share many common imaging features as well. However, certain imaging features, particularly in combination with a matching clinical scenario, play a pivotal role in diagnosing these conditions and directing further evaluation. In this article, we review common and rare hematologic malignancies of the GI tract and discuss their pathophysiologic, clinical, and imaging features.

Primary testicular diffuse large B-cell lymphoma: Case series

RATIONALE

Primary testicular lymphoma (PTL) is a rare type of extranodal non-Hodgkin's lymphoma (NHL). Although data of PTL in patients with diffuse large B-cell lymphoma (DLBCL) are accumulating, there are still patients respond poorly to prognosis.

PATIENT CONCERNS

All patients had disease of the DLBCL subtype and those patients had primary involvement of the testis. In our studies, eleven patients had stage I/II disease, and 3 patients had advanced disease with B symptoms. Four patients exhibited a MYC+, BCL2+, and BCL6- expression pattern, 4 patients had a MYC+, BCL6+, and BCL2- expression pattern, and 3 patients had a MYC+, BCL2+, and BCL6+ expression pattern. Additionally, 43% (7/16) of PT-DLBCL patients had a germinal center B-cell-like (GCB) phenotype, while the others had a non-GCB phonotype.

DIAGNOSES

In our case, most patients presented with unilateral painless scrotal swelling and the enlargement of the testicles in the first examination. After hospitalization, all patients underwent preoperative imageological examination of the testis and epididymis and postoperative revealed that all patients were the diffuse infiltration of a large number of anomalous lymphocytes. In addition, no invasion of other sites was observed within 3 months after diagnosis.

INTERVENTIONS AND OUTCOMES

Underwent orchiectomy on the affected side was performed by urologists after all patients were diagnosed with PTL. Meanwhile, some patients received at least one course of chemotherapy, or received postoperative combined RT and chemotherapy. Because of it particularity, nineteen instances of lymph node region involvement were discovered in 12 patients since the operation.

LESSONS

PT-DLBCL has unique biological characteristics, and its treatment modalities are becoming increasingly standardized. In the future, systematic interventions need to be actively considered in the early stages of PTL.

Prognostic impact of abdominal lymph node involvement in diffuse large B-cell lymphoma

Objective

The prognostic value of site of nodal involvement in diffuse large B‐cell lymphomas (DLBCL) is mainly unknown. We aimed to determine the prognostic significance of nodal abdominal involvement in relation to tumour cell markers and clinical characteristics of 249 DLBCL patients in a retrospective single‐centre study.

Methods

Contrast‐enhanced computed tomography (CT) of the abdomen and thorax revealed pathologically enlarged abdominal lymph nodes in 156 patients, while in 93 patients there were no pathologically enlarged lymph nodes in the abdomen. In 81 cases, the diagnosis of DLBCL was verified by histopathological biopsy obtained from abdominal lymph node.

Results

Patients with abdominal nodal disease had inferior lymphoma‐specific survival (P = .04) and presented with higher age‐adjusted IPI (P < .001), lactate dehydrogenase (P < .001) and more often advanced stage (P < .001), bulky disease (P < .001), B symptoms (P < .001), and double expression of MYC and BCL2 (P = .02) compared to patients without nodal abdominal involvement, but less often extranodal involvement (P < .02). The worst outcome was observed in those where the abdominal nodal involvement was verified by histopathological biopsy.

Conclusion

Diffuse large B‐cell lymphomas patients with abdominal nodal disease had inferior outcome and more aggressive behaviour, reflected both in clinical and biological characteristics.

Colorectal diffuse large B-cell lymphoma: molecular subclassification and prognostic significance of immunoglobulin gene translocation

Primary colorectal diffuse large B-cell lymphoma (DLBCL) is rare, and its clinicopathological and genetic features are poorly understood. The aim of our study was to elucidate the frequency and prognostic significance of molecular subgroups in colorectal DLBCL. We examined 25 cases of colorectal lymphoma with DLBCL-like morphology and classified them into germinal center B-cell like (GCB)/non-GCB subgroups by immunohistochemistry (IHC) for CD10, bcl-6 and MUM1, or into double-expressor (DE)/non-DE subgroups by IHC for bcl-2 and c-myc. Translocations involving BCL2, BCL6, MYC, IGH, IGK, IGL, and MALT1 were also investigated using break-apart fluorescence in situ hybridization (FISH). The 25 cases were classified into two entities-DLBCL, not otherwise specified (NOS) (n = 23; 92%) and high grade B-cell lymphoma, double hit (n = 2; 8%)-according to the recent WHO classification. None of them showed histological evidence of Epstein-Barr virus infection or high-grade transformation from low grade B-cell lymphoma. Ten cases were GCB-type and four cases were DE-type, but these subtypes did not contribute to clinicopathological differences. Translocations involving BCL2, BCL6, MYC, IGH, IGK, IGL, and MALT1 were detected in 3 (12%), 3 (12%), 10 (40%), 14 (56%), 3 (12%), 3 (12%), and 0 (0%) of 25 cases, respectively. Of note, the presence of IGH translocation was significantly associated with better overall survival (P = .0053) and progression free survival (P = .0259). Similarly, the translocation involving at least one of the IGs (IGH, IGK, and/or IGL) was associated with more favorable prognosis in DLBCLs or even in DLBCL, NOS. This is the first report to reveal that a small subset of colorectal DLBCL corresponds to double-hit lymphoma. In addition, translocations involving at least one of the IGs may be a favorable prognostic factor in colorectal DLBCL. Testing the translocation involving rearrangement of IGs as well as MYC and BCL2/BCL6 may thus be useful for diagnosis and prognosis.

Diffuse large B-cell lymphoma variants: an update

Diffuse large B-cell lymphoma (DLBCL) is the most common type of lymphoma, representing approximately one-third of all cases worldwide. In the World Health Organization (WHO) classification of lymphomas, most cases of DLBCL are designated as not otherwise specified (NOS). About 20% of cases, however, are designated as specific variants of DLBCL. These variants, 13 in total, are specified on the basis of distinctive morphological or immunophenotypic findings or distinctive biological or clinical issues associated with their diagnoses. In this review we discuss the following variants: T-cell/histiocyte-rich large B-cell lymphoma; ALK-positive large B-cell lymphoma; plasmablastic lymphoma; intravascular large B-cell lymphoma; large B-cell lymphoma with IRF4 rearrangement; primary mediastinal large B-cell lymphoma; primary cutaneous diffuse large B-cell lymphoma, leg type; primary diffuse large B-cell lymphoma of the central nervous system; diffuse large B-cell lymphoma associated with chronic inflammation; lymphomatoid granulomatosis; primary effusion lymphoma; and HHV8-positive diffuse large B-cell lymphoma, NOS. Two additional variants recognised in the WHO classification, EBV-positive diffuse large B-cell lymphoma and EBV-positive mucocutaneous ulcer are discussed elsewhere in another review within this issue of Pathology. Although not recognised as a specific variant in the current WHO classification, primary testicular diffuse large B-cell lymphoma also has unique biological features and requires some modification of the standard treatment approach for patients with DLBCL. Therefore, we suggest that primary testicular diffuse large B-cell lymphoma also should be recognised as a specific variant of DLBCL in a future version of the WHO classification.

Gastric diffuse large B-cell lymphoma with bilateral adrenal metastasis

Extranodal adrenal involvement in non-Hodgkin's lymphoma is very rare, estimated to be around less than 0.2%. Most common sites involved are stomach, intestine and testis. It is very rare for adrenal tumours to present as primary adrenal insufficiency, with an incidence of around 1.2% in patients diagnosed with adrenal masses. Diffuse large B cell lymphoma (DLBL) originating from the stomach and metastasizing to bilateral adrenal glands is an extremely uncommon occurrence with only three cases found on review of the literature. We present a case of a 62-year-old African-American man who presented with nausea, vomiting, abdominal pain and hypotension, later being diagnosed as DLBL of the gastric antrum metastasized to bilateral adrenal glands. Initial laboratory workup revealed including hormonal analysis and cosyntropin test revealed adrenal insufficiency. The patient later died during the hospitalisation after developing respiratory failure, severe hypotension refractory to vasopressors and severe metabolic acidosis.