Presentation and management of intravascular large B-cell lymphoma. Lancet Oncol. 2009;10:895-902. [PMID: 19717091 DOI: 10.1016/s1470-2045(09)70140-8]

Rare intravascular large B-cell lymphoma (IVLBCL) can cause atypical intracerebral haemorrhage and mislead diagnostics

Intravascular large B-cell lymphoma (IVLBCL) is a rare type of non-Hodgkin's lymphoma. Common neurological symptoms are cognitive impairment and dementia. Only a few cases have been published reporting intracranial haemorrhage due to IVLBCL. We present a case of a female patient in her late 60s who presented with an atypical intracerebral haemorrhage as the first major complication of an IVLBCL. The patient's condition declined rapidly. She died several weeks later due to haemorrhagic shock. The definitive diagnosis was achieved postmortem. Due to aggressive disease progression, the diagnosis of IVLBCL is still challenging and can therefore lead to incorrect or delayed treatment, especially in cases of unusual manifestations like lobar intracranial haemorrhage.

THE UTILITY OF THE NORMAL THIN SECTION SKIN BIOPSY IN THE ASSESSMENT OF SYSTEMIC/EXTRACUTANEOUS DISEASE

BACKGROUND

Diseases reflective of multiorgan vascular injury of diverse etiology, peripheral nerve disease, dysautonomia syndromes and intravascular lymphoma malignancies may potentially exhibit abnormalities on a normal skin biopsy that may be instrumental in establishing a diagnosis.

MATERIALS AND METHODS

A retrospective review of our data base was conducted to uncover cases where a normal skin biopsy was performed to rule in or out certain systemic diseases such as complement driven thrombotic microvascular disease including atypical hemolytic uremic syndrome, post transplant thrombotic microangiopathy, and severe/critical COVID-19, systemic capillary leak syndrome, cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) intravascular B cell lymphoma, dysautonomia syndromes and mast cell activation syndrome. Immunohistochemical stains were conducted inclu C5b-9, CD56, MXA, B and T cell markers.

RESULTS

There were expected patterns critical in establishing diagnosis based on evaluating certain parameters including assessing for increased C5b-9 microvascular deposition from the deltoid area(atypical hemolytic uremic syndrome, post-transplant thrombotic microangiopathy, catastrophic antiphospholipid antibody syndrome and severe/critical COVID-19), enhanced type I interferon signaling (systemic capillary leak syndrome), ultrastructural arteriopathic changes (CADASIL),lower extremity reduced cutaneous autonomic innervation (small fiber neuropathy and POTS), abdominal, thigh and buttock skin for the presence of intravascular lymphocytes on biopsy(intravascular B cell lymphoma), distinct structural changes in elastic fibers supportive of pseudoxanthoma elasticum and a higher than normal density of mast cells in the absence of other inflammatory cell types (mast cell activation syndrome).

CONCLUSION

The skin is a critical window for understanding disease, a concept well exemplified by the myriad of diseases that can be suggested by the microscopic and or ultrastructural examination of clinically normal skin, hence establishing the normal skin biopsy as an important tool for understanding extracutaneous disease.

Clinicopathological characteristics, prognostic factors, and outcomes of elderly patients with lymphoma-associated hemophagocytic lymphohistiocytosis: A multicenter analysis

BACKGROUND

Lymphoma is the most common secondary cause of hemophagocytic lymphohistiocytosis (HLH) in adults. Lymphoma-associated HLH (LA-HLH) in the elderly population is not rare, however, little has been reported regarding clinicopathological characteristics, prognostic factors, and outcomes of LA-HLH in the elderly population.

METHODS

We retrospectively analyzed a multicenter cohort of elderly patients with LA-HLH. Clinicopathological features and treatment information were collected. The impacts of baseline characteristics and treatments on survival outcomes were analyzed.

RESULTS

A total of 173 elderly patients with LA-HLH were included. Compared with young patients, elderly patients showed different clinical and laboratory features. Regarding lymphoma subtypes, B-cell lymphoma was more common in elderly patients (elderly 61.3% vs. young 32.3%, p < 0.001) while T/NK-cell lymphoma was more common in young patients (65.3% vs. 35.3%, p < 0.001). The median survival of elderly patients with LA-HLH was only 92 days. The prior use of HLH therapy or etoposide-containing HLH therapy was not associated with improved overall survival. T/NK-cell subtype, a lower platelet count (≤53 × 109/L), a lower albumin level (≤32.1 g/L), a higher LDH level (>1407 U/L), and a higher creatinine level (>96.8 μmol/L) were independent predictors of decreased overall survival and 60-day survival. A prognostic index was established and demonstrated to be robust in predicting the overall survival and 60-day survival of elderly patients with LA-HLH.

CONCLUSIONS

LA-HLH in elderly patients displayed heterogeneous clinicopathological features and survival outcomes. Treatments need to be optimized to improve the outcomes of elderly patients with LA-HLH.

Generalized Telangiectasia as a Hallmark of Intravascular Lymphoma: A Case Report and Literature Review

A 55-year-old woman had remarkably generalized telangiectasia. Large atypical lymphoid cells were found within the lumen of small vessels, and CD20 was positive in her third skin biopsy. She was diagnosed with intravascular large B-cell lymphoma (IVLBCL) and went into remission of the skin manifestations after seven courses of R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone) and four courses of intravenous high-dose methotrexate (HD MTX). To our knowledge, this is the first case report of IVLBCL with generalized telangiectasia in China. From a review of the literature, we found that generalized telangiectasia is a remarkable manifestation of intravascular lymphoma, and the differential diagnosis of intravascular lymphoma and panniculitis or vasculitis is very important. When the diagnosis is confusing, multiple skin biopsies are useful.

Plasma circulating tumour DNA is a better source for diagnosis and mutational analysis of IVLBCL than tissue DNA

Diagnosis of intravascular large B-cell lymphoma (IVLBCL) is a challenge due to its heterogeneous clinical presentation and lack of specific markers. This retrospective study investigated the utility of circulating tumour DNA (ctDNA) sequencing for diagnosing IVLBCL and analysing its mutation landscape. A cohort of 34 IVLBCL patients enrolled and underwent plasma ctDNA targeted sequencing. The median plasma ctDNA concentration was 135.0 ng/mL, significantly higher than that in diffuse large B-cell lymphoma (DLBCL) controls. Correlations were found between ctDNA concentration and disease severity indicators, LDH and SF. Mutation analysis revealed frequent mutations in B-cell receptor and NF-κB signalling pathways, including MYD88 (56%), CD79B (44%), TNFAIP3 (38%) and IRF4 (29%). CNS involvement was significantly related with BCL6 and CD58 mutation. Patients with complicated hemophagocytic lymphohistiocytosis had significantly higher mutation rates in B2M. Comparison with DLBCL subtypes showed distinctive mutation profiles in IVLBCL. Moreover, plasma ctDNA detected more mutations with higher variant allele fraction than tissue DNA, suggesting its superiority in sensitivity and accessibility. Dynamic monitoring of ctDNA during treatment correlated with therapeutic responses. This study revealed the role of ctDNA in IVLBCL diagnosis, mutation analysis, and treatment monitoring, offering a promising avenue for improving patient diagnosis in this rare lymphoma subtype.

Insulin-like Growth Factor II mRNA-binding Protein 3 is a Highly Sensitive Marker for Intravascular Large B-cell Lymphoma: Immunohistochemical Analysis of 152 Pathology Specimens From 88 Patients

Intravascular large B-cell lymphoma (IVLBCL) is a rare type of aggressive extranodal large B-cell lymphoma characterized by the selective growth of lymphoma cells within the lumina of blood vessels, particularly capillaries. IVLBCL lacks mass formation, and its diagnosis can be challenging. We analyzed the utility of insulin-like growth factor II mRNA-binding protein 3 (IMP3) immunohistochemistry for IVLBCL diagnosis in various organs. Double staining with paired box 5 (PAX5) was performed for validation. Overall, 152 pathological specimens (111 positive and 41 negative for IVLBCL) obtained from 88 patients with a diagnosis of IVLBCL were stained for IMP3 and IMP3/PAX5. As negative controls, 40 pathology specimens from 38 patients with no history of IVLBCL or other B-cell lymphomas were stained for IMP3, which comprised 31 benign pathological specimens from 29 patients in whom malignancy was suspected, 7 cases of appendicitis with intravascular and/or intralymphatic lymphoid proliferations, and 2 cases of intravascular natural killer/T-cell lymphoma. All mononuclear cells with cytoplasmic staining were considered positive for IMP3 expression, but expression restricted to germinal center B cells was excluded from evaluation. All 111 IVLBCL pathological specimens were positive for IMP3 and IMP3/PAX5. In addition, 11 of the 41 specimens originally diagnosed as IVLBCL-negative showed IMP3/PAX5 double-positive cells, raising the suspicion of IVLBCL. However, of the 40 negative control samples, IMP3-positive non-germinal center B cells were detected in only 2 samples ( P = 0.0131) and no intravascular IMP3-positive B cells suspicious for IVLBCL were identified. Altogether, IMP3 immunohistochemistry is a highly sensitive marker of IVLBCL and can be a helpful adjunct for IVLBCL diagnosis.

Whole-exome sequencing is feasible on a fresh-frozen skin sample of intravascular large B cell lymphoma

Intravascular large B-cell lymphoma (IVLBCL) is a rare aggressive extranodal non-Hodgkin lymphoma. The predominant, if not exclusive, growth of neoplastic cells within the lumina of small-sized vessels represents the hallmark of the disease. Diagnosis is challenging due to the absence of marked lymphadenopathy, the highly heterogeneous clinical presentation, and the rarity of the condition. Clinical presentation is characterized by variable combinations of nonspecific signs and symptoms (such as fever and weight loss), organ-specific focal manifestations due to altered perfusion, and hemophagocytic syndrome. The rarity of this entity and the paucity of neoplastic cells in biopsy samples hamper the study of recurrent molecular abnormalities. The purpose of this study was to explore the feasibility of a different approach to recover a sufficient amount of DNA of acceptable quality to perform next-generation sequencing studies. Here, we report the findings of whole-exome next-generation sequencing performed on a fresh-frozen cutaneous sample of IVLBCL, paired with the patient saliva used as germline DNA. To increase the cancer cell fraction, only the subcutaneous tissue was selected. With this approach, we obtained high-quality DNA and were able to identify oncogenic mutations specific for this entity and recapitulating its post-germinal center origin, even if the tumor fraction was low. Molecular studies performed on fresh-frozen cutaneous sample are feasible in IVLBCL, especially when analysis is restricted to the subcutaneous tissue. Wide adoption of this reproducible and cost-effective approach may foster further studies, which may be of help in supporting diagnosis, providing pathogenetic insights, and guiding treatment decisions.

Intravascular Large B-cell Lymphoma Presenting as Pulmonary Ground-glass Nodules That Progressed Slowly over Several Months with No Overt Symptoms

A 74-year-old man with no overt symptoms was referred for a chest computed tomography (CT) that revealed multiple bilaterally pulmonary ground-glass nodules (GGNs) with subtle changes in size over eight months. Surgical lung biopsies were performed in the left upper lobe. A pathologic study confirmed the intravascular large B-cell lymphoma (IVLBCL). This lesion was a nodule-like cluster of atypical cells, meaning that it had been localized for several months. Pulmonary IVLBCL may form focal lesions presenting as GGN on chest CT and progress slowly without apparent symptoms.

Effective management of a rare case of primary renal intravascular large B-cell lymphoma with modified R-CHOP regimen: A case report

Intravascular large B-cell lymphoma, known for its diverse organ involvement, presents significant diagnostic challenges, particularly when it affects the kidneys. This report highlights a rare case of primary renal intravascular large B-cell lymphoma in a 60-year-old male patient, who presented with persistent fever and renal dysfunction. The case underscores the intricacy of diagnosis and the efficacy of personalized treatment. Following the identification of primary renal intravascular large B-cell lymphoma, a modified R-CHOP regimen was administered, resulting in notable amelioration of symptoms and renal function following the initial treatment cycle. The patient achieved sustained complete remission without any complications after completing five subsequent R-CHOP cycles and two additional cycles of rituximab monotherapy, as confirmed by recent assessments. He is currently under regular follow-up for ongoing monitoring and improvement. This case adds to the limited yet expanding pool of knowledge concerning intravascular large B-cell lymphoma, emphasizing the necessity for personalized therapeutic strategies in atypical presentations. It also highlights the importance of early detection and customized intervention in managing rare lymphoma subtypes with unique organ involvement.

A Case of Weight Gain and Edema With Difficulty in Moving Legs Due to Intravascular Large B-cell Lymphoma Diagnosed by Skin Biopsy

We report a case of intravascular large B-cell lymphoma (IVL) with spinal cord involvement. A 76-year-old woman was referred to our department due to generalized edema and weight gain. She also had difficulty moving her legs. She had no superficial lymphadenopathy upon examination. Her laboratory tests showed a markedly elevated blood lactate dehydrogenase (LDH) level. Although heart failure or interstitial lung disease was initially suspected, she was diagnosed with IVL by skin biopsy. An MRI revealed spinal cord involvement. Post-hospitalization, she began rituximab-combined chemotherapy. In this case, we considered that the spinal cord involvement of the lymphoma caused the neurogenic bladder and leg weakness. IVL often infiltrates the central nervous system and presents with neurological symptoms, including neurogenic bladder. Therefore, imaging studies should be planned to search for the involvement of the central nervous system in lymphoma if accompanied by neurological symptoms. In addition, in patients with a markedly elevated LDH or soluble interleukin-2 receptor level without lymphadenopathy, IVL should be suspected, and consultation with hematologists should be considered.

Primary pulmonary intravascular large B‑cell lymphoma misdiagnosed as pneumonia: Four case reports and a literature review

Primary pulmonary intravascular large B-cell lymphoma (IVLBCL) is a rare, malignant extranodal lymphoma. It is difficult to diagnose clinically as it requires a combination of clinical and computed tomography (CT) evaluations, as well as laboratory and pathological examinations. In the present study, 4 cases of primary pulmonary IVLBCL were reviewed. The patients' ages ranged from 60 to 69 years old. Of the 4 patients, 3 developed progressive dyspnea on exertion and intermittent fever. Other symptoms included coughing, chest tightness and weight loss. Laboratory data indicated that all patients had anemia, thrombocytopenia, hypoxemia, a markedly high serum lactate dehydrogenase level, elevated erythrocyte sedimentation rate and increased C-reactive protein. CT demonstrated increased attenuation in bilateral lung parenchyma, especially in the upper lobes, with multiple ground-glass opacities associated with small nodules in these patients. Initially, all 4 patients were misdiagnosed with pneumonia. However, none of them responded to anti-inflammatory treatments. The pathologies of all patients were confirmed using lung biopsy. Only 1 patient received regular combination chemotherapy. Based on the observations of the present study, a standard regimen for lymphoma treatment may result in a notable clinical response.

Clinical Spectrum, Diagnosis, and Treatment Outcome in Individuals With Intravascular Large B-cell Lymphoma Affecting the Nervous System: A Case Series

We treated five patients, three females, and two males, with intravascular lymphoma that affected the central or peripheral nervous systems. We reviewed their clinical, laboratory, neuro-imaging, and pathological data and treatment outcomes. The median age of onset was 60 years, with a range of 39 to 69 years. Three patients presented with central nervous system symptoms only, such as confusion, aphasia, seizure, stroke, and ataxia. Three patients presented with systemic lymphoma stage B symptoms, one with peripheral nervous system symptoms, and one with multi-organ failure. Brain imaging revealed white matter lesions, infarcts, hemorrhages, or combinations. Histology showed CD20-positive B-lymphocytes confined to small-size vessels in autopsy or biopsy specimens from the brain or muscle, confirming the diagnosis of intravascular large B-cell lymphoma (IVLBL). The patient with multi-organ failure had diffuse infiltration to the spleen, liver, and kidney. Three patients died within three to four months after the clinical presentation and were diagnosed at autopsy. The other two were diagnosed by biopsy and underwent chemotherapy CHOP-R (cyclophosphamide, hydroxydaunorubicin, Oncovin, and prednisone) or MTX (methotrexate)+Rituximab. The median survival of the chemotherapy patients was 17.5 months, compared to three to four months in those who did not receive chemotherapy. Although IVLBL has distinct pathological features, its clinical presentation can be variable. The patient's best chance for survival depends on the early pathological diagnosis and prompt, aggressive chemotherapy.

Clinical utility of positron emission tomography leading to rapid and accurate diagnosis of intravascular large B-cell lymphoma presenting with the central nervous system symptoms alone: A case report and review of the literature

Background:

Intravascular large B-cell lymphoma (IVLBCL) is a rare entity among large B-cell non-Hodgkin lymphomas and is often difficult to diagnose. We report the case of a patient with IVLBCL who presented with central nervous system (CNS) symptoms alone, in which positron emission tomography (PET) enabled a rapid and accurate diagnosis.

Case Description:

An 81-year-old woman was admitted to our hospital with a 3-month history of gradually progressive dementia and declining spontaneity. Magnetic resonance imaging revealed multiple hyperintense lesions bilaterally on diffusion-weighted imaging without enhancement on gadolinium-enhanced T1-weighted imaging. Laboratory findings showed elevated serum lactate dehydrogenase (626 U/L) and soluble interleukin-2 receptor (sIL-2R) (4692 U/mL). Cerebrospinal fluid (CSF) analysis showed slightly elevated levels of protein (166 mg/dL) and lymphocytic cells (29/μL), and β2-microglobulin (β2-MG) (4.6 mg/L) was highly elevated. Whole-body computed tomography revealed faint ground-glass opacities in the upper and middle lung fields and diffuse enlargement of both kidneys without lymph node swelling. 18F-fluorodeoxyglucose (FDG)-PET showed diffuse and remarkably high FDG uptake in both upper lungs and kidneys without uptake by lymph nodes, suggesting a malignant hematological disease. IVLBCL was confirmed histologically by incisional random skin biopsy from the abdomen. Chemotherapy using R-CHOP regimen in combination with intrathecal methotrexate injection was started on day 5 after admission and follow-up neuroimaging showed no signs of recurrence.

Conclusion:

IVLBCL presenting with CNS symptoms alone is rare and often has a poor prognosis associated with delayed diagnosis, and various evaluations (including systemic analysis) are therefore necessary for early diagnosis. FDG-PET, in addition to identification of clinical symptoms and evaluation of serum sIL-2R and CSF β2-MG, enables rapid therapeutic intervention in IVLBCL presenting with CNS symptoms.

Intravascular Large B-Cell Lymphoma Genomic Profile Is Characterized by Alterations in Genes Regulating NF-κB and Immune Checkpoints

Intravascular large B-cell lymphoma (IVLBCL) is an uncommon lymphoma with an aggressive clinical course characterized by selective growth of tumor cells within the vessels. Its pathogenesis is still uncertain and there is little information on the underlying genomic alterations. In this study, we performed a clinicopathologic and next-generation sequencing analysis of 15 cases of IVLBCL using a custom panel for the detection of alterations in 68 recurrently mutated genes in B-cell lymphomagenesis. Six patients had evidence of hemophagocytic syndrome. Four patients presented concomitantly a solid malignancy. Tumor cells outside the vessels were observed in 7 cases, 2 with an overt diffuse large B-cell cell lymphoma. In 4 samples, tumor cells infiltrated lymphatic vessel in addition to blood capillaries. Programmed death-ligand 1 (PD-L1) was positive in tumor cells in 4 of 11 evaluable samples and in macrophages intermingled with tumor cells in 8. PD-L1 copy number gains were identified in a higher proportion of cases expressing PD-L1 than in negative tumors. The most frequently mutated gene was PIM1 (9/15, 60%), followed by MYD88L265P and CD79B (8/15, 53% each). In 6 cases, MYD88L265P and CD79B mutations were detected concomitantly. We also identified recurrent mutations in IRF4 , TMEM30A , BTG2 , and ETV6 loci (4/15, 27% each) and novel driver mutations in NOTCH2 , CCND3 , and GNA13 , and an IRF4 translocation in 1 case each. The mutational profile was similar in patients with and without evidence of hemophagocytic syndrome and in cases with or without dissemination of tumor cells outside the vessels. Our results confirm the relevance of mutations in B-cell receptor/nuclear factor-κB signaling and immune escape pathways in IVLBCL and identify novel driver alterations. The similar mutational profile in tumors with extravascular dissemination suggests that these cases may also be considered in the spectrum of IVLBCL.

[A case of intravascular large B-cell lymphoma manifested as lacunar infarction]

A 79-year-old man was admitted to our hospital because of sudden onset of left ataxic hemiparesis. Brain MRI diffusion weighted images showed typical lacunar infarction on the right internal capsule. He had no risk factors of cerebrovascular disorder such as hypertension, diabetes mellitus, hyperlipidemia and arrhythmia. On admission, he had a slight fever and his laboratory data showed anemia, thrombocytopenia and elevation of CRP and LDH. Intravascular large B-cell lymphoma (IVLBCL) was suspected because the serum level of soluble IL-2 receptor was also elevated. Pathological diagnosis of IVLBCL was underwent by the skin biopsy from his senile hemangiomas. Although IVLBCL was known to demonstrate various CNS lesions, it is extremely rare to be manifested as a single lacunar infarction, and this case must be important for the differential diagnosis.

The Relevance of Skin Biopsies in General Internal Medicine: Facts and Myths

INTRODUCTION

Non-dermatology medical specialties may refer patients for skin biopsies, searching for a particular diagnosis. However, the diagnostic impact of the skin biopsy is not clearly established. This article aims to assess the indications for, and evaluate the clinical relevance of, skin biopsies in non-dermatology medical specialties.

METHODS

A questionnaire was sent to 23 non-dermatology specialty departments in a university medical center, requesting a list of indications for skin biopsies, as well as to 10 staff dermatologists to collect the indications of skin biopsies requested by non-dermatology specialties. Once the indications were collected, a literature search was performed to evaluate their clinical value and relevance.

RESULTS

Eleven non-dermatology specialties provided a list of skin biopsy indications, to which staff dermatologists added seven more indications. A literature search revealed evidence-based medicine data for six diseases, that is, amyloidosis, peripheral autonomic neuropathy, Sneddon's syndrome, intravascular lymphoma, sarcoidosis, and chronic graft-versus-host disease. Results were questionable concerning infectious endocarditis, acute graft-versus-host-disease, and the lupus band test. Skin biopsy were not evidenced as useful for the diagnosis of calciphylaxis, systemic scleroderma, Behçet's disease, or hypermobile Ehlers-Danlos syndrome. For the diagnosis of Alport's syndrome, pseudoxanthoma elasticum, and vascular Ehlers-Danlos syndrome, skin biopsy is currently outperformed by genetic analyses. For diagnoses such as Henoch-Schönlein purpura and Sjögren's syndrome, skin biopsy represents an additional item among other diagnostic criteria.

CONCLUSION

The usefulness of skin biopsy as requested by non-dermatology specialties is only evidenced for amyloidosis, peripheral autonomic neuropathy, Sneddon's syndrome, intravascular lymphoma, sarcoidosis, chronic graft-versus-host-disease, Henoch-Schönlein purpura, and Sjögren's syndrome.

Intravascular lymphoma masquerading as septic shock

Intravascular lymphoma (IVL) is a rare type of extranodal lymphoma that selectively affects small blood vessels. We report a patient who presented with dyspnea and weight loss as well as refractory shock and multiple-organ dysfunction. The postmortem revealed disseminated involvement of an IVL but no evidence of infection.

Reactive Intralymphovascular Immunoblastic Proliferations Mimicking Aggressive Lymphomas

Reactive intralymphovascular immunoblastic proliferations (ILVIPs) may mimic aggressive lymphomas and are rarely reported. Herein, we characterize the clinicopathologic features of 8 patients with ILVIPs. No patients had lymphadenopathy, hepatosplenomegaly, or other findings suggestive of lymphoma. The ILVIPs involved the small or large intestine (n=5) and appendix (n=3). Patients were evaluated for abdominal pain, suspected appendicitis, intestinal obstruction, diverticulitis, volvulus, or tumor resection. Histologic sections showed expanded lymphovascular spaces filled by intermediate to large immunoblasts, positive for CD38, CD43, CD45, CD79a, and MUM1/IRF4 in all cases tested. Five of 6 (83%) cases were positive for CD30. CD20 was weakly positive in a subset of cells in 2 (25%) cases, and PAX5 was weakly positive in 4 (50%) cases. The immunoblasts expressed polytypic light chains in all cases tested. In 1 case, a subset of immunoblasts expressed T-cell markers indicating the presence of a T-cell component. The immunoblasts were negative for ALK, BCL-2, BCL-6, CD10, CD56, CD138, and Epstein-Barr virus-encoded small RNA in all cases assessed. The proliferation index shown by Ki-67 was high with a median of 80%. In all 6 cases tested, the immunoblasts were shown within lymphatic channels highlighted by D2-40. In conclusion, ILVIPs can be rarely observed in patients with inflammatory or infectious conditions, especially in gastrointestinal tract surgical specimens. The immunoblasts are predominantly of B-lineage with a postgerminal center immunophenotype and are located within lymphatic channels. It is essential to distinguish reactive ILVIPs from aggressive lymphomas to avoid unnecessary therapy.

Intravascular Large B-Cell Lymphoma

CONTEXT.—

Intravascular large B-cell lymphoma (IVLBCL) is a rare hematopathologic entity, posing both a clinical and histologic challenge for diagnosis. Numerous pitfalls can hinder making the diagnosis.

OBJECTIVE.—

To summarize recent developments in literature pertaining to IVLBCL and point out key pitfalls pathologists should be prepared to encounter.

DATA SOURCES.—

Literature review via PubMed search and hospital (Darnall Medical Library) resources.

CONCLUSIONS.—

The 3 primary pitfalls of IVLBCL include masking of IVLBCL, mimicry by IVLBCL, and mimicry of IVLBCL. These scenarios illustrate the importance of histologic pattern recognition and subsequent usage of immunohistochemistry, especially in context of a clinical history that may be noncharacteristic.

Intravascular large B-cell lymphoma presenting as rapidly progressive dementia and stroke: A case report

RATIONALE

Intravascular large B-cell lymphoma (IVLBCL) is a rare form of large B-cell non-Hodgkin lymphoma. The diagnosis is challenging and frequently made at biopsy. Here we reported a case of IVLBCL limited to the central nervous system (CNS) presenting with progressive dementia and acute stroke, who was diagnosed by brain biopsy.

PATIENT CONCERNS

A 47-year-old woman was transferred to our hospital with a 6-month history of rapidly progressive dementia, and left limb weakness and numbness for 3 days. She was successively misdiagnosed with inflammatory demyelinating disease and stroke. Her condition deteriorated with elevated lactate dehydrogenase and multiple hyperintense lesions on the brain.

DIAGNOSIS

She was diagnosed with IVLBCL limited to the CNS by brain biopsy.

INTERVENTIONS

Bone marrow puncture and incisional random skin biopsy were not found neoplastic cells. Computed tomography scans were normal with no evidence of disease outside the CNS.

OUTCOMES

The patient died due to rapid clinical aggravation.

LESSONS

IVLBCL limited to the CNS is an aggressive disease with high mortality. Making a timely and correct diagnosis is crucial for early appropriate treatment in IVLBCL patients.

Intravascular Large B Cell Lymphoma of the Breast: A Rare Entity

Intravascular large B-cell lymphoma (IVLBCL) is a rare and high-grade disease of neoplastic lymphoid cells within the vascular lumina of small- to medium-sized vessels. The disease carries a grim prognosis despite robust treatment protocols. We discuss the case of a 58-year-old female who presented with mammographic screening abnormality which led to more investigations and ultimately to this diagnosis. The patient had no prior history of a lymphoma or in situ and invasive carcinoma of the breast. To our knowledge, IVLBCL of the breast is a very rare and an unusual location for this type of a lymphoma and so far, only five reported cases. Through our case report, we not only discuss the case but also review literature on this rare entity.

Intravascular large B-cell lymphoma: representative cases and approach to diagnosis

Intravascular large B-cell lymphoma (ILBCL) is a subtype of non-Hodgkin's large B-cell lymphoma that is characterised by neoplastic lymphocyte proliferation within the lumen of small blood vessels, which may occur without an extracellular tumour mass or peripheral blood involvement. This report highlights some of the diagnostic issues for ILBCL, and how it can be approached. The two cases described below highlight two significantly different presentations, one with predominately neurological phenomena, and the other with fever of unknown origin for investigation. Both patients were managed with chemotherapy and intercalated intrathecal chemotherapy, with good clinical outcomes, without further evidence of clinical relapse. These cases along with a review of the literature highlight the key learning points in the difficulties in the diagnosis of this condition, and the appropriate use of random skin biopsy in patient suspected of having ILBCL, such as those with constitutional symptoms with otherwise negative malignancy screening, and unexplained neurological phenomena, especially if recurrent in nature.

The Rare Face of an Infrequent Lymphoma Diagnosed by an Exquisite Method: Case Report with Review of Literature

Large B-cell lymphomas include both the commonly encountered, as well as not so frequent entities. We report a rare case of hepatic intravascular large B-cell lymphoma (IVLBCL). These cases usually pose a major challenge to timely diagnosis due to the limited clinical exposure and nonspecific symptoms; however, timely diagnosis is possible with awareness of this entity and close coordination between radiology and pathology. The patient presented with pain abdomen, fever, edema, hepatomegaly but no lymphadenopathy or cutaneous lesions were identified. Blood investigations revealed pancytopenia, high lactate dehydrogenase (LDH) levels and bone marrow investigations were not helpful. Left-sided portal hypertension, coagulopathy, and hypoalbuminemia raised a clinical suspicion of chronic liver disease with high LDH levels and liver biopsy was challenging in view of very low platelet counts. The uniquely explored transjugular biopsy helped in obtaining liver tissue which showed sinusoidal large atypical lymphoid cells positive for CD20 rendering a diagnosis of IVLBCL. After administration of the R-miniCHOP chemotherapy, there was evident clinical and radiological response. This case highlights the importance of considering transjugular liver biopsy in scenarios where the clinical presentation is unusual. At the same time, a meticulous histological examination is needed to diagnose a rare yet potentially treatable large B cell lymphoma.

Imaging Features and Prognostic Value of FDG PET/CT in Patients with Intravascular Large B-Cell Lymphoma

Purpose

The clinical value of ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) in intravascular large B-cell lymphoma (IVLBCL) is unknown. This study investigated the association between PET/CT features and prognosis in IVLBCL patients.

Patients and Methods

Subjects were 30 newly diagnosed Asian variant IVLBCL patients at a single institution. Baseline PET/CT was analyzed for the distribution and intensity of FDG lesions, and PET/CT pattern groups were compared for the outcome.

Results

Eight patients had hypermetabolic lymph node (LN) lesions (Nodal group). The remaining 22 patients with extranodal (EN) involvement were categorized into Deauville score 3–4 (EN/DS3-4; n = 14) and DS5 groups (EN/DS5; n = 8). First-line therapy resulted in a complete or partial response in 75.0%, 64.3%, and 100% of the respective groups. Treatment-related deaths occurred in one nodal group and three EN/DS3-4 group cases, but none among the EN/DS5 group. During 56 months of follow-up, disease progression or relapse occurred in five, four, and one case of respective groups. Cancer-related death occurred more frequently in the Nodal (n = 6) and EN/DS3-4 groups (n = 7) than the EN/DS5 group (n = 1; P = 0.041). Nodal and EN/DS3-4 groups had worse 5-year event-free survival (EFS; 25.0% and 49.0%, respectively, P = 0.010 and 0.076) and overall survival (OS; 33.3% and 48.2%, P = 0.010 and 0.068) compared to the EN/DS5 group (87.5% EFS and 87.5% OS).

Conclusion

In patients with Asian variant IVLBCL, the distribution and intensity of FDG uptake lesions on PET/CT can be useful for predicting treatment outcomes and survival.

A case of intravascular large B cell lymphoma with brain involvement mimicking progressive multifocal leukoencephalopathy

Intravascular large B-cell lymphoma (IVLBCL) is a very rare form of extranodal lymphoma, characterized by the proliferation of neoplastic B cells within the lumen of small vessels. Due to its high aggressivity, for years the prognosis had been really poor with only anectodical cases of remission after traditional chemotherapy. More recently, new therapeutic protocols allowed a significant increase in overall survival. It can virtually involve every organ, being skin and central nervous system the most affected. The clinical presentation is often unspecific and insidious; therefore, diagnosis can be challenging. Tissue biopsy, in particular random deep skin biopsy, is the gold standard for definitive diagnosis. We describe the case of a 58-year-old woman with a previous diagnosis of myelofibrosis, who presented with a rapidly progressive neurological deterioration and a brain MRI suggestive of Progressive Multifocal Leukoencephalopathy. Due to the absence of BK and JC viruses in cerebrospinal fluid and the presence of severe myalgias and subcutaneous nodules, a skin and muscle biopsy was performed, allowing diagnosis of IVLBCL. We describe the diagnostic pitfalls of this case, briefly reviewing existing literature about IVLBCL.

Painful purpura from intravascular large B-cell lymphoma cutaneous variant

Intravascular large B-cell lymphoma is a rare disease that often goes unnoticed and is repeatedly diagnosed during autopsy. Patients present with a wide variety of nonspecific symptoms, which makes the diagnosis challenging. This case presents a patient who was initially diagnosed with fever of unknown origin but later developed a retiform purpuric rash that prompted the diagnosis.

Intravascular Large B-Cell Lymphoma Presenting as Acute Axonal Polyneuropathy: A Case Report and Literature Review

Intravascular large B-cell lymphoma (ILBL) is a rare and difficult to diagnose subtype of large B-cell lymphoma. The most common locations of presentation are in the central nervous system and the skin, but there are reports of other organ involvement. Due to the indolence, nonspecific symptoms, and rarity of the disease, this form of lymphoma is most often diagnosed postmortem. In this article, we describe a case of ILBL that presented as a rapidly progressive acute axonal polyneuropathy. Acute axonal polyneuropathy is a common disease process with a wide differential diagnosis, but there is limited literature on its prevalence as the presenting symptom of ILBL. This patient was treated with R-EPOCH and intrathecal methotrexate with significant improvement in his polyneuropathy after 1 cycle, and complete remission after 6 cycles. Data on chemotherapy regimens and their success rates for this disease are lacking.

Neuropathies périphériques associées aux syndromes lymphoprolifératifs : spectre clinique et démarche diagnostique

Lymphoproliferative syndromes (multiple myeloma, Waldenström's disease, chronic lymphocytic leukemia, lymphomas) may be associated with peripheral neuropathies. The mechanism can be dysimmune, associated or not with monoclonal gammopathies; paraneoplastic; infiltrative; or more commonly, iatrogenic or due to vitamin deficiency. The diagnosis can be complex, especially when the neuropathy is the presenting manifestation, requiring a close cooperation between internists and neurologists. The positive diagnosis of the neuropathy is based on a systematic electro-clinical investigation, which specifies the topography and the mechanism of the nerve damage, sometimes reinforced by imaging examinations, in particular, nerve and/or plexus MRI. The imputability of the neuropathy to a lymphoproliferative syndrome is based on a set of arguments including the clinical context (B signs, tumour syndrome), first-line laboratory tests (hemogram, protein electrophoresis, viral serologies, complement), auto-antibodies discussed according to the neuropathy (anti-MAG, anti-gangliosides) and sometimes more invasive examinations (bone marrow or neuro-muscular biopsies).

Occult Diffuse Neoplasm in the Lungs: Intravascular Large B-Cell Lymphoma

BACKGROUND

Intrathoracic involvement with lymphomas is common and manifests lymphadenopathy as well as a wide spectrum of imaging abnormalities in the lungs. Intravascular large B-cell lymphoma (IVLBCL) is a rare extranodal subtype of large B-cell lymphoma that typically involves small blood vessels and is difficult to detect.

METHODS

Using a computer-assisted search, we identified patients with histopathologically proven IVLBCL in the lungs at Mayo Clinic from 2001 through 2018. Medical records, imaging studies, and pathologic specimens were reviewed.

RESULTS

A total of 5 patients were diagnosed with a median age at diagnosis of 68 years (range, 44-73); 4 patients were male. The diagnosis of IVLBCL was achieved by surgical lung biopsy in 3 and at autopsy in 2. At presentation, all 5 patients had dyspnea and systemic symptoms including fever, fatigue, night sweats, and/or weight loss. Chest radiography and computed tomography (CT) failed to demonstrate the diffuse infiltrative process; positron emission tomography (PET) scan performed in 2 patients did not show fluorodeoxyglucose (FDG) uptake in the lungs. Pulmonary function tests obtained in 3 patients showed reduced diffusing capacity in all; transthoracic echocardiography yielded evidence of pulmonary hypertension in 2 of 4 patients. All 3 patients diagnosed antemortem underwent chemotherapy with 1 patient remaining alive at 4 years after diagnosis.

CONCLUSIONS

IVLBCL is difficult to diagnose given variable and nonspecific clinical presentations. Microvascular disease processes such as IVLBCL should be kept in mind in cases of undiagnosed progressive dyspnea accompanied by systemic symptoms even when imaging studies are unrevealing.

Episodic Visual Distortions and Stroke-Like Symptoms in a 56-Year-Old Man With Intravascular Lymphoma

A healthy 56-year-old man presented with vision changes and left upper extremity motor and sensory changes. MRI of the brain without contrast was significant for multifocal areas of restricted diffusion in multiple vascular territories. Neuro-Ophthalmic evaluation revealed an inferonasal visual field defect in the left eye, thickened choroid on optical coherence tomography, and bilateral delayed arteriovenous and choroidal filling on fluorescein angiogram. Repeat MRI demonstrated interval enlargement of many of the same foci of abnormal diffusion-weighted imaging signal. Computed tomography of the abdomen and pelvis revealed 3 distinct lobulated retroperitoneal masses that were biopsied and found to be consistent with diffuse large B-cell lymphoma. Brain biopsy specimens showed intravascular lymphocytes, confirming a diagnosis of intravascular lymphoma (IVL). In this diagnostically challenging case, a link was established between the presence of multiple strokes (some of which showed slow evolution over time) and retinochoroidal hypoperfusion, which provided a critical clue to the ultimate diagnosis of IVL.

Intravascular lymphoma presenting with hypoxaemia, platypnoea and lactic acidosis

Intravascular large B-cell lymphoma (IVLBCL) is an aggressive and rare type of diffuse extranodal B-cell lymphoma. Diagnosis and treatment are challenging and clinical presentation is variable. Physicians should be aware of this rare but life-threatening lymphoma without adenopathy and treatment should be promptly started. We describe the case of a 70-year-old woman who presented with general malaise, acute dyspnoea, platypnoea and lactic acidosis. Echocardiography revealed an extracardiac shunt, the cause of her orthodeoxia. The patient developed rapid liver failure and underwent liver biopsy. Anatomopathological findings suggested IVLBCL, non-germinal center type. She achieved complete remission after rituximab, cyclophosphamide, doxorubicin, vincristine, methylprednisolone chemotherapy but relapsed 1 year after initial presentation with multiple organ involvement. The patient's relapsed disease was treated with rituximab, iphosphamide, carboplatin, etoposide and she is still in complete remission 2 years later.

Intravascular large B-cell lymphoma as a recurrence of primary central nervous system lymphoma after chemotherapy: A case report

We report about a 48-year-old woman diagnosed with primary central nervous system lymphoma (PCNSL). After chemotherapy and autologous stem cell transplantation, she presented with a continuous high-grade fever. Positron emission tomography-computed tomography revealed prominent hepatosplenomegaly and high diffuse uptake of 18F-fluorodeoxyglucose in the liver, spleen, and lungs. Intravascular large B-cell lymphoma (IVLBCL) was diagnosed using random skin biopsy. There were no symptoms of IVLBCL at the time of diagnosis of PCNSL. The histopathological features of PCNSL and IVLBCL were nearly similar. These findings suggest that IVLBCL was the recurrence of PCNSL rather than a separate entity.

The clinicopathological and molecular features of sinusoidal large B-cell lymphoma

We report 17 cases of sinusoidal large B-cell lymphoma (SLBCL). Clinical, morphologic, immunophenotypic, and molecular features were detected and analyzed. All cases showed an obvious sinusoidal growth pattern, usually associated with residual atrophic lymphoid tissue. All tumors contained large pleomorphic lymphoid cells and one or more prominent nucleoli, with abundant amphophilic cytoplasms; 15/17 cases showed anaplastic morphologic features. The patient age ranged from 43 to 80 years (median 57 years), and 7 males and 10 females were included. Eleven of 15 (73.3%) patients had Ann Arbor stage III or IV disease, and 10/15 (66.6%) patients had an International Prognostic Index (IPI) score ≥3. Immunophenotypically, 16/17 (94.1%) cases displayed a nongerminal center B-cell (non-GCB) immunophenotype. Furthermore, 16/17 (94.1%) cases were positive for CD30, and p53 was expressed in 10/16 (62.5%) cases. In total, 12/14 (85.7%) cases expressed BCL2 and MYC simultaneously (double expression), and 11/14 (78.6%) cases showed PD-L1 positivity (6/11 had a PD-L1 tumor proportion score ≥50%). Cytogenetically, concurrent MYC and BCL2 and/or BCL6 abnormalities (break-apart or extra copy) were detected in 10/15 cases, and 7/13 (53.8%) cases harbored a PD-L1/L2 amplification. TP53 mutation was found in 7/13 (53.8%) cases by Sanger sequencing. Whole-exome and large-panel sequencing results revealed high mutation frequencies of TP53 (4/7), MYD88 (3/7), KMT2D (3/7), CREBBP (3/7), and PIM1 (3/7). Among the 13 patients with SLBCL treated with aggressive chemotherapy regimens, the median overall survival (OS) was 18 months, and the 2-year OS rate was 34.6%. The OS of patients with SLBCL was markedly worse than that of 35 control group patients with common diffuse large B-cell lymphoma (DLBCL) without sinusoidal features (P < 0.001). SLBCL may represent a specific type of DLBCL that has characteristic pathologic features. The cancer is aggressive in most clinical cases, and outcomes are poor. SLBCL and anaplastic DLBCL (A-DLBCL) have many overlapping clinicopathological and molecular features.

A Case of Intravascular Diffuse Large B-Cell Lymphoma Initially Suspected as Interstitial Pneumonia Associated With Systemic Scleroderma

Intravascular large B-cell lymphoma (IVLBCL) is a rare form of diffuse LBCL. The patient was a 71-year-old female admitted to our hospital with hypoxia. On admission, chest computed tomography revealed a ground-glass opacity. Interstitial pneumonia associated with systemic scleroderma was suspected because of positive anti-centromere antibody. Thereafter, steroid pulse therapy and plasma exchange were performed. Although ground-glass opacity improved, bilateral pleural effusion appeared, so we performed a random skin biopsy because of her elevated serum lactate dehydrogenase and soluble interleukin-2 receptor levels. The patient was diagnosed with IVLBCL with symptoms improving after 6 cycles of rituximab plus chemotherapy treatment.

Intravascular large B-cell lymphoma presenting with reticular telangiectasia on the trunk and panhypopituitarism: an autopsy case

A 75-year-old woman developed redness and swelling on her truncal skin, spreading from the lower abdomen to left thigh, 2 months before being admitted to our hospital. She was urgently hospitalised because of her worsening respiratory condition. On admission, she had reticular telangiectasia, diffuse skin induration on the lower abdomen and panhypopituitarism. She was diagnosed with intravascular large B-cell lymphoma (IVLBCL) by the third random abdominal skin biopsy. After histopathological examination at autopsy, we made a final diagnosis of IVLBCL causing respiratory failure and panhypopituitarism. This is the rare case of IVLBCL-induced panhypopituitarism showing visible skin lesions.

Immune cartography of macrophage activation syndrome in the COVID-19 era

A hyperinflammatory 'cytokine storm' state termed macrophage activation syndrome (MAS), culminating from a complex interplay of genetics, immunodeficiency, infectious triggers and dominant innate immune effector responses, can develop across disparate entities including systemic juvenile idiopathic arthritis (sJIA) and its counterpart adult-onset Still disease (AOSD), connective tissue diseases, sepsis, infection, cancers and cancer immunotherapy. Classifying MAS using the immunological disease continuum model, with strict boundaries that define the limits of innate and adaptive immunity, at one boundary is MAS with loss of immune function, as occurs in the 'perforinopathies' and some cases of sJIA-AOSD. Conversely, at the other boundary, immune hypersensitivity with gain of immune function in MHC class II-associated sJIA-AOSD and with chimeric antigen receptor (CAR) T cell therapy also triggers MAS. This provides a benchmark for evaluating severe inflammation in some patients with COVID-19 pneumonia, which cripples primary type I interferon immunity and usually culminates in a lung-centric 'second wave' cytokine-driven alveolitis with associated immunothrombosis; this phenomenon is generally distinct from MAS but can share features with the proposed 'loss of immune function' MAS variant. This loss and gain of function MAS model offers immune cartography for a novel mechanistic classification of MAS with therapeutic implications.

Intravascular Large B-Cell Lymphoma and Renal Clear Cell Carcinoma as Collision Tumor: A Case Report and Review of the Literature

Intravascular large B-cell lymphoma (IVLBCL) is a rare type of extranodal large B-cell lymphoma characterized by the selective growth of lymphoma cells within the lumina of vessels. The patient usually presents with nonspecific symptoms and a remarkable deterioration in performance status. The occurrence of synchronous IVLBCL and renal cell carcinoma (RCC) is extremely rare. A right kidney tumor was found in a 72-year-old man with a history of low back pain. The kidney was enlarged, with a tumor mass measuring 4.5 × 4 × 4 cm. Sections exhibited a RCC (clear cell type, nuclear grade I). Also an extensive tumor affecting capillaries and small veins was present, positive for CD45, CD20, BCL-2, and MUM1/IRF-4, consistent with IVLBCL. The lymphoma was circumscribed to the RCC. The final diagnosis was IVLBCL with a RCC as collision tumor. After that, with neurological findings, central nervous system compromise by lymphoma was made. The patient started a first cycle of chemotherapy, progressive deterioration of the sensorium, and positive blood cultures for Klebsiella pneumoniae and Escherichia coli. The patient died 8 days later of acute respiratory failure. No autopsy was done. IVLBCL is an aggressive and systemic disease characterized by massive proliferation of tumor cells without a known primary site. Clinical identification and histopathologic diagnosis are relevant issues in the therapeutic management of these lymphomas. Until now, only one case of IVLBCL coexisting with RCC has been reported. In this article, we report a second case of IVLBCL with RCC simultaneous, as an unusual collision tumor.

Interleukin-6-producing Intravascular Large B-cell Lymphoma with Lymphadenopathy Mimicking the Histology of Multicentric Castleman Disease

An inguinal lymph node biopsy of a woman with a one-month history of a progressive fever, fatigue, dyspnea, skin rash, and lymphadenopathy revealed a well-preserved basic structure, hyperplastic germinal centers, and an interfollicular region containing polyclonal plasma cell sheets, suggesting plasma cell-type multicentric Castleman disease (MCD). We initiated prednisolone and anti-interleukin (IL)-6 antibody (tocilizumab), without success. A biopsy specimen re-evaluation detected CD20-positive atypical large B cells infiltrating the small vessels within and around the lymph node and its capsule. We diagnosed her with intravascular large B-cell lymphoma (IVLBCL). Lymphoma cells were weakly positive for IL-6 by immunohistochemical staining. IL-6 from lymphoma cells may have caused the MCD-like presentation as a paraneoplastic etiology. Malignant lymphoma should be excluded before diagnosing MCD.

Prognosis of Intravascular Large B Cell Lymphoma (IVLBCL): Analysis of 182 Patients from Global Case Series

Purpose

This study provides an overview of the prognosis of intravascular large B cell lymphoma (IVLBCL) over the past 10 years and analyzes the possible relevant factors.

Patients and Methods

We conducted a literature search of case reports, case series, and retrospective studies of IVLBCL published from January 2008 to July 2018. After excluding inappropriate data, 103 publications were selected for the analysis. Statistical analyses of different treatment modalities, the effect of blood–brain barrier (BBB)-penetrating drugs, and prognostic factors for outcomes were performed.

Results

In total, 182 pathologically confirmed cases of IVLBCL were included in our study. The results revealed that the 1- and 3-year overall survival rates were 42.3 and 11.5%, respectively, whereas the median overall survival was 340 days. Overall survival (450 days vs 180 days) and progression-free survival (420 days vs 150 days) were significantly longer in patients who received rituximab-containing regimens than in those treated with other regimens. For IVLBCL involving the CNS, regimens containing BBB-penetrating drugs failed to provide an additional survival benefit. In addition, lactic dehydrogenase levels ≥700 U/L, CNS involvement, and hemophagocytic syndrome were identified as unfavorable risk factors in patients with IVLBCL, whereas skin involvement appeared to be a protective factor.

Conclusion

Rituximab-containing chemotherapy can improve the outcomes of patients with IVLBCL, but the prognosis remains unsatisfactory. Treatment regimens containing BBB-penetrating drugs failed to improve outcomes in patients with CNS-involved IVLBCL. Several factors affect the prognosis of patients with IVLBCL, and further research on the underlying mechanisms is needed.

Identification of a novel cancer stem cell subpopulation that promotes progression of human fatal renal cell carcinoma by single-cell RNA-seq analysis

Background: Cancer stem cells (CSCs) are biologically characterized by self-renewal, multi-directional differentiation and infinite proliferation, inducing anti-tumor drug resistance and metastasis. In the present study, we attempted to depict the baseline landscape of CSC-mediated biological properties, knowing that it is vital for tumor evolution, anti-tumor drug selection and drug resistance against fatal malignancy.

Methods: We performed single-cell RNA sequencing (scRNA-seq) analysis in 15208 cells from a pair of primary and metastatic sites of collecting duct renal cell carcinoma (CDRCC). Cell subpopulations were identified and characterized by t-SNE, RNA velocity, monocle and other computational methods. Statistical analysis of all single-cell sequencing data was performed in R and Python.

Results: A CSC population of 1068 cells was identified and characterized, showing excellent differentiation and self-renewal properties. These CSCs positioned as a center of the differentiation process and transformed into CDRCC primary and metastatic cells in spatial and temporal order, and played a pivotal role in promoting the bone destruction process with a positive feedback loop in the bone metastasis microenvironment. In addition, CSC-specific marker genes BIRC5, PTTG1, CENPF and CDKN3 were observed to be correlated with poor prognosis of CDRCC. Finally, we pinpointed that PARP, PIGF, HDAC2, and FGFR inhibitors for effectively targeting CSCs may be the potential therapeutic strategies for CDRCC.

Conclusion: The results of the present study may shed new light on the identification of CSCs, and help further understand the mechanism underlying drug resistance, differentiation and metastasis in human CDRCC.

Intravascular lymphoma with hypopituitarism: A case report

BACKGROUND

Intravascular lymphoma (IVL) is a rare subtype of lymphoma involving the growth of lymphoma cells within the vessel lumina without lymphadenopathy. Because of various modes of presentation and its rarity, IVL is often diagnosed postmortem. Herein, we report a case of intravascular B-cell lymphoma with hypopituitarism, an extremely rare complication, that was successfully treated with chemotherapy.

CASE SUMMARY

An 80-year-old Japanese woman presented with a 7-mo history of a tingling sensation in the lower limbs. She also presented with various other symptoms such as pancytopenia, high fever daily, and unconsciousness with hypoglycemia. Although the doctor who previously treated her diagnosed hypoglycemia as being due to hypopituitarism, the cause of the other symptoms remained uncertain despite a 7-mo evaluation period. We performed bone marrow aspiration to evaluate pancytopenia and found that she had hemophagocytic lymphohistiocytosis (HLH). On the basis of a random skin biopsy for assessing the cause of HLH, she was diagnosed with intravascular B-cell lymphoma. HLH and hypopituitarism were considered secondary to IVL. All her clinical findings matched the presentations of IVL. She was immediately treated with chemotherapy and achieved complete response. She was relapse free two years after treatment.

CONCLUSION

IVL should be included in the differential diagnosis of hypopituitarism, which although life-threatening, is treatable through prompt diagnosis and appropriate chemotherapy.

Cytogenetic complexity and heterogeneity in intravascular lymphoma

AIMS

To characterise the karyotypic abnormalities and heterogeneities in intravascular lymphoma (IVL).

METHODS

G-banded karyotyping was performed on biopsy specimens from a single-centre IVL cohort comprising intravascular large B-cell lymphoma (IVLBCL, n=12) and NK/T-cell lymphoma (IVNKTCL, n=1).

RESULTS

Five IVLBCL cases and one IVNKTCL case (total 46%) were found to have normal karyotypes, and the cytogenetic abnormalities observed in the other seven IVLBCL cases (54%) were investigated further. These seven karyotypes were uniformly complex with an average of 13 aberrations. The seven cases all had abnormalities involving chromosome 6, with 57% involving structural abnormalities at 6q13, and chromosome 8, with 43% involving abnormalities at 8p11.2. In addition, 71% had aberrations at 19q13. On average, 4.4 chromosomal gains and losses were detected per case. Cytogenetic heterogeneities were observed in six cases (86%) and tetraploidy in three cases (43%). There was no significant difference in progression-free survival (p=0.92) and overall survival (p=0.61) between the IVLBCL cases with complex and normal karyotypes.

CONCLUSION

Approximately half of IVLBCL cases had a highly heterogeneous pattern of karyotypes with different clonal numerical and structural chromosome aberrations.

Molecular Diagnostics in Lymphoid Neoplasms of the Central Nervous System

Primary lymphoid neoplasms of the central nervous system are rare tumors that span a wide range of histopathologic appearances and can overlap occasionally with non-neoplastic processes. Application of modern molecular techniques has not only begun to unravel their unique underlying biology but has also started to lay a valuable diagnostic and therapeutic framework for these frequently aggressive malignancies. This review summarizes the existing landscape of clinicopathologic and genomic features of lymphoid neoplasms that may arise primarily within the central nervous system.

PD-L1 (SP142) expression in neoplastic cells predicts a poor prognosis for patients with intravascular large B-cell lymphoma treated with rituximab-based multi-agent chemotherapy

Background

Intravascular large B‐cell lymphoma (IVLBCL) is a rare form of diffuse large B‐cell lymphoma (DLBCL) arising in extranodal sites. PD‐L1 expression of tumor cells has been reported in IVLBCL cells, but its clinicopathological relevance remains to be elucidated.

Aims

This study was aimed to reveal the characteristics of PD‐L1⁺ IVLBCL.

Methods and results

Neoplastic PD‐L1 expression was examined in 34 cases of IVLBCL and clinicopathological characteristics between patients with PD‐L1⁺ and PD‐L1⁻ IVLBCL were compared. We assessed PD‐L1 expression with SP142 antibody. Twelve (35%) of 34 cases showed positivity for PD‐L1. The PD‐L1⁺ group had significantly lower survival rates compared to the PD‐L1⁻ group. The PD‐L1⁺ IVLBCL group also had a significantly lower age distribution and a lower frequency of patients older than 60 years compared to the PD‐L1⁻ group. Very recently, we speculate that there is possible link between PD‐L1⁺ IVLBCL and PD‐L1⁺ extranodal DLBCL‐NOS (eDLBCL) because features of the two groups showed overlapping. Therefore, we compared the clinicopathological characteristics of the PD‐L1⁺ IVLBCL and PD‐L1⁺ eDLBCL. There were no significant differences in clinicopathological parameters and prognosis.

Conclusion

The worse prognosis of the PD‐L1⁺ group might be caused by immune evasion mechanisms, which are linked to PD‐L1 expression. Therefore, PD‐L1⁺ IVLBCL cases might be regarded as good candidates for targeted immunotherapy. We also highlighted the overlapping features of PD‐L1⁺ IVLBCL and PD‐L1⁺ eDLBCL. This result suggests that they should be regarded as one entity, immune evasion‐related extranodal large B‐cell lymphoma.

Transcriptome complexity in intravascular NK/T-cell lymphoma

AIMS

Intravascular NK/T-cell lymphoma (IVNKTCL) is a rare disease, which is characterised by exclusive growth of large cells within the lumen of small vessels, Epstein-Barr virus infection and somatic mutations in epigenetic regulator genes. Here, we elucidate the transcriptomic complexity of IVNKTCL.

METHODS

IVNKTCL cases were retrieved from a single-centre cohort of 25 intravascular lymphomas. RNA-seq and whole exome sequencing (WES) were performed to analyse transcriptomic abnormalities and mutations in splicing factors.

RESULTS

Approximately 88% of the total reads from the RNA-seq were considered exonic, while the remaining reads (12%) were mapped to intronic or intergenic regions. We detected 28,941 alternative splicing events, some of which would produce abnormal proteins rarely found in normal cells. The detected events also included tumour-specific splicing alterations in oncogenes and tumour suppressors (e.g., HRAS, MDM2 and VEGFA). WES identified premature termination mutations or copy number losses in a total of 15 splicing regulator genes, including SF3B5, SRSF12 and TNPO3.

CONCLUSIONS

This study raises the possibility that IVNKTCL may be driven by multiple complex regulatory loops, including non-exonic expression and aberrant splicing, in addition to defects in epigenetic regulation.

Rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone combined with high-dose methotrexate plus intrathecal chemotherapy for newly diagnosed intravascular large B-cell lymphoma (PRIMEUR-IVL): a multicentre, single-arm, phase 2 trial

BACKGROUND

Intravascular large B-cell lymphoma (IVLBCL) is a rare disease for which there is no available standard treatment. We aimed to ascertain the safety and activity of R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone) with high-dose methotrexate and intrathecal chemotherapy as CNS-oriented therapy for patients with previously untreated IVLBCL.

METHODS

PRIMEUR-IVL is a multicentre, single-arm, phase 2 trial at 22 hospitals in Japan. Eligible patients had untreated histologically confirmed IVLBCL, were aged 20-79 years, had an Eastern Cooperative Group performance status of 0-3, and had no apparent CNS involvement at diagnosis. Patients received three cycles of R-CHOP (rituximab 375 mg/m² intravenously on day 1 [except cycle one, which was on day 8]; cyclophosphamide 750 mg/m², doxorubicin 50 mg/m², and vincristine 1·4 mg/m² [maximum 2·0 mg] intravenously on day 1 of cycle one and day 2 of cycles two and three; and prednisolone 100 mg/day orally on days 1-5 of cycle one and days 2-6 of cycles two and three) followed by two cycles of rituximab with high-dose methotrexate (3·5 g/m² intravenously on day 2 of cycles four and five) every 2 weeks and three additional cycles of R-CHOP. Intrathecal chemotherapy (methotrexate 15 mg, cytarabine 40 mg, and prednisolone 10 mg) was administered four times during the R-CHOP phase. The primary endpoint was 2-year progression-free survival. Efficacy analyses were done in all enrolled patients; safety analyses were done in all enrolled and treated patients. The trial is registered in the UMIN Clinical Trials Registry (UMIN000005707) and the Japan Registry of Clinical Trials (jRCTs041180165); the trial is ongoing for long-term follow-up.

FINDINGS

Between June 16, 2011, and July 21, 2016, 38 patients were enrolled, of whom 37 were eligible; one patient was excluded because of a history of testicular lymphoma. Median follow-up was 3·9 years (IQR 2·5-5·5). 2-year progression-free survival was 76% (95% CI 58-87). The most frequent adverse events of grade 3-4 were neutropenia and leucocytopenia, which were reported in all 38 (100%) patients. Serious adverse events were hypokalaemia, febrile neutropenia with hypotension, hypertension, and intracerebral haemorrhage (reported in one [3%] patient each). No treatment-related deaths occurred during protocol treatment.

INTERPRETATION

R-CHOP combined with rituximab and high-dose methotrexate plus intrathecal chemotherapy is a safe and active treatment for patients with IVLBCL without apparent CNS involvement at diagnosis, and this regimen warrants future investigation.

FUNDING

The Japan Agency for Medical Research and Development, the Center for Supporting Hematology-Oncology Trials, and the National Cancer Center.