When Waldenström macroglobulinemia hits the kidney: Description of a case series and management of a "rare in rare" scenario.

BACKGROUND: Renal injury related to Waldenström macroglobulinemia (WM) occurs in approximately 3% of patients. Kidney biopsy is crucial to discriminate between distinct histopathological entities such as glomerular (amyloidotic and non-amyloidotic), tubulo-interstitial and non-paraprotein mediated renal damage. In this context, disease characterization, management, relationship between renal, and hematological response have been poorly explored. We collected clinical, genetic and laboratory data of seven cases of biopsy-proven renal involvement by WM managed at our academic center and focused on three cases we judged paradigmatic discussing their histopathological patterns, clinical features, and therapeutic options. CASE: In this illustrative case series, we confirm that serum creatinine levels and 24 h proteinuria are parameters that when altered should prompt the clinical suspicion of WM-related renal involvement, even if at present there are not precise cut-off levels recommending the execution of a renal biopsy. In our series AL Amyloidosis (n = 3/7) and tubulo-interstitial infiltration by lymphoma cells (n = 3/7) were the two more represented entities. BTKi did not seem to improve renal function (Case 1), while bortezomib-based regimens demonstrated a beneficial activity on the hematological and organ response, even when used as second-line therapy after chemoimmunotherapy (Case 3) and also with coexistence of anti-MAG neuropathy (Case 2). In case of poor response to bortezomib, standard chemoimmunotherapy (CIT), such as rituximab-bendamustine, represents an effective option (Case 1, 6, and 7). In our series, CIT generates durable responses more frequently in cases with amyloidogenic renal damage (Case 1, 5, and 7). CONCLUSION: In this illustrative case series, we confirm that serum creatinine levels and 24 h proteinuria are parameters that when altered should prompt the clinical suspicion of WM-related renal involvement, even if at present there are not precise cut-off levels recommending the execution of a renal biopsy. Studies with higher numerosity are needed to better clarify the pathological and clinical features of renal involvement during WM and to determine the potential benefit of different therapeutic regimens according to the histopathological subtypes.

A 74-Year-Old Man With Waldenström Macroglobulinemia and Progressive Dyspnea.

CASE PRESENTATION: A 74-year-old man presented to our department with progressive dyspnea on exertion over the last year. The patient did not report any other symptoms. He had previously smoked with a 60 pack-year history. He worked in an office and did not report any environmental, occupational, or domestic exposures. His history included asymptomatic Waldenström's macroglobulinemia that was diagnosed 18 months before respiratory symptoms. He was not receiving any treatment and was monitored regularly by the hematology department.

Bing-Neel syndrome: a rare neurological complication of Waldenström macroglobulinaemia.

Bing-Neel syndrome (BNS) is a very rare manifestation of Waldenström macroglobulinaemia (WM), in which lymphoplasmacytic cells invade the central nervous system. The clinical presentation includes symptoms of headaches, visual floaters, neuropathy, seizures and gait abnormalities. Here, we describe an elderly woman, who presented with complaints of visual floaters, progressive neuropathy and cognitive changes. Workup including a bone marrow biopsy confirmed the diagnosis of WM. Shortly afterwards, the patient experienced a seizure leading to hospitalisation, which revealed a right frontal lobe lesion on brain MRI. A biopsy of the lesion showed a small B cell lymphoma positive for an MYD88 mutation, confirming BNS. The patient was initially treated with ibrutinib, before transitioning to zanubrutinib. However, she developed disease progression necessitating radiotherapy with lenalidomide and rituximab maintenance therapy, which achieved remission. This case sheds light on the diagnosis and management of a very rare complication of a rare disease.

Clinical, biological, electrophysiological and therapeutic profile of patients with anti-MAG neuropathy according to MYD88L265P and CXCR4 mutations and underlying haemopathy.

INTRODUCTION: Anti-MAG neuropathies are associated with an IgM monoclonal gammopathy of undetermined significance (MGUS) or with a malignant haemopathy. Our objective was to determine whether the presence of a haemopathy or somatic mutations of MYD88 and CXCR4 genes influences disease presentation and response to rituximab (RTX). METHODS: We included 79 patients (mean age 74 years, disease duration 9.68 years) who had a bone marrow aspiration with morphologic and immunophenotypic analysis. MYD88L265P and CXCR4 mutations were analysed in peripheral B cells. Information collected included: inflammatory neuropathy cause and treatment sensory sum score (ISS), MRC testing, overall neuropathy limitation scale (ONLS), Rash-built Overall Disability Score (RODS), ataxia score, anti-MAG titres, peak IgM dosage, neurofilament light chain levels, motor and sensory amplitudes, motor unit index (MUNIX) and motor unit size index (MUSIX) sum scores. Efficacy of RTX was evaluated at 12 months in 26 patients. RESULTS: Malignant haematological disorders were discovered in 17 patients (22%): 13 Waldenstrom macroglobulinemia, 3 marginal zone lymphoma and one mantle cell lymphoma. MYD88L265P mutation was detected in 29/60 (48%) patients and CXCR4 in 1 single patient. Disease severity, biological and electrophysiological data and response to RTX were comparable in patients with MGUS/lymphoma and patients with/without MYD88L265P mutation. ISS was lower and MUSIX higher in patients improved by RTX. CONCLUSIONS: MYD88L265P mutation and underlying haemopathies are not predictive of a more severe disease. However, in cases of resistant and progressive neuropathy, they provide an opportunity to prescribe newly available drugs such as Bruton tyrosine kinase inhibitors.

Waldenström's Macroglobulinemia and Cryoglobulinemic Glomerulonephritis: An Unusual Case of Monoclonal Gammopathy of Renal Significance.

Cryoglobulins are immunoglobulins that precipitate at temperatures below 37 °C and dissolve upon reheating. They can induce small-vessel vasculitis with renal involvement. Cryoglobulinemic glomerulonephritis is a rare manifestation that occurs in patients with monoclonal gammopathy, specifically Waldenström's macroglobulinemia. We present the case of a 52-year-old patient with a history of cutaneous vasculitis and hypothyroidism, who presented with generalized edema, moderate anemia, hypercholesterolemia, nephrotic range proteinuria of 12.69 g/day, microhematuria, arterial hypertension, and hypocomplementemia via the classical pathway, without acute kidney injury and with negative serological studies and positive cryoglobulins in the second determination. Serum and urine protein electrophoresis and immunofixation studies showed a monoclonal band of IgM and kappa light chain. Renal biopsy was consistent with cryoglobulinemic glomerulonephritis. In the context of dysproteinemia and cryoglobulinemic glomerulonephritis, bone-marrow aspiration and biopsy were performed, leading to the diagnosis of Waldenström's macroglobulinemia. Monoclonal gammopathies have been described in association with type I cryoglobulinemias. This described association is uncommon, which is why we present this case, along with a review of the literature.

[The 503rd case: monoclonal IgM immunoglobulinemia, severe anemia with recurrent fever].

A 42-year-old woman was diagnosed with Waldenström macroglobulinemia (WM) with fatigue, anemia, and monoclonal IgM immunoglobulinemia 6 years prior. She experienced persistent severe anemia with only transient remission after initial chemotherapy and after multiple chemotherapy regimens and immunosuppressive therapies, which were accompanied by recurrent high fever with severe complications including urinary infection, sepsis and shock, rectal perforation, and severe obstructive jaundice. The anemia was diagnosed as warm autoimmune hemolytic anemia and aplastic crisis with inflammation anemia. She received ibrutinib 140 mg once a day, and her hemoglobin levels returned to normal. WM remained stable in very good partial remission with no infection.

A Rare Case of Subcutaneous Amyloidoma Associated with Localized Lymphoplasmacytic Lymphoma: Diagnostic Challenges and Treatment Considerations.

BACKGROUND AL amyloidomas are solitary, localized, tumor-like deposits of immunoglobulin light-chain-derived amyloid fibrils in the absence of systemic amyloidosis. A rare entity, they have been described in various anatomical sites, typically in spatial association with a sparse lymphoplasmacytic infiltrate, ultimately corresponding to a clonal, malignant, lymphomatous disorder accounting for the amyloidogenic activity. Most frequently, the amyloidoma-associated hematological disorder corresponds to either a solitary plasmacytoma or an extranodal marginal zone lymphoma of MALT. Much rarer is the association with lymphoplasmacytic lymphoma, which by itself is usually a bone marrow-bound disorder with systemic burden. The almost anecdotic combination of an amyloidoma and a localized lymphoplasmacytic lymphoma deserves attention, as it entails a thorough diagnostic workup to exclude systemic involvement and a proportionate therapeutic approach to avoid overtreatment. A review of the literature provides an insight on pathogenesis and prognosis, and can assist both pathologists and clinicians in establishing optimal patient management strategies. CASE REPORT We herein report the incidental finding of a subcutaneous amyloidoma caused by a spatially related, similarly localized lymphoplasmacytic lymphoma diagnosed in a 54-year-old female patient with no other disease localizations and a complete remission following 2 subsequent surgical excisions. CONCLUSIONS Whatever the specific combination of an amyloidoma and the related hematological neoplasm, a multidisciplinary collaboration and a comprehensive clinical-pathological staging are warranted to exclude systemic involvement and identify patients with localized diseases who would benefit from local active treatment and close follow-up.

A Case of Bing-Neel Syndrome Presenting Like Giant Cell Arteritis.

ABSTRACT: A 55-year-old woman presented with new-onset headache, scalp tenderness, shoulder arthralgias, night sweats, and loss of appetite. She was diagnosed with giant cell arteritis by her primary care physician and commenced on oral corticosteroids. However, her headache, scalp tenderness, and night sweats persisted. She then developed right Horner syndrome and trigeminal hypoesthesia. Extensive blood work-up revealed mildly elevated inflammatory markers and a paraproteinemia. Subsequent bone marrow biopsy showed lymphoplasmacytic lymphoma, with 10% of hemopoiesis, and staging led to the diagnosis of Waldenstrom macroglobulinemia without nodal or central nervous system (CNS) lesions. Immunohistochemical staining of a temporal artery biopsy showed perivascular lymphoplasmacytic cells and paraprotein deposits. She was diagnosed with CNS involvement of her macroglobulinemia-Bing-Neel syndrome (BNS). Identification of rare CNS involvement of lymphoma is challenging when a patient is already on steroid immunosuppression. In the absence of clear diagnostic criteria, the rare and heterogenous BNS remains a clinical diagnosis.

Bing-Neel syndrome with a paravertebral mass.

Bing-Neel syndrome, a rare neurological complication of Waldenström macroglobulinemia, is caused by the direct infiltration of malignant lymphoplasmacytic cells into the central nervous system. We report a patient who presented with back pain, weakness, lower extremity numbness, and gait disturbance accompanied by immunoglobulin M paraproteinemia and lymphoplasmacytic lymphoma in the bone marrow. Thoracic and lumbar magnetic resonance imaging revealed a long paravertebral mass around the spinal column, but the direct infiltration could not be proven. The patient was diagnosed with possible Bing-Neel syndrome and managed with bendamustine and rituximab. After chemotherapy, the patient's neurological and radiological findings improved. Magnetic resonance imaging should be considered when the Bing-Neel syndrome diagnosis is unclear.

PARACENTRAL ACUTE MIDDLE MACULOPATHY AS AN EARLY SIGN OF WALDENSTRÖM MACROGLOBULINEMIA.

PURPOSE: To report a case of paracentral acute middle maculopathy as the earliest sign of an undiagnosed, life-threatening hyperviscosity syndrome. METHODS: A 78-year-old man with an acute paracentral scotoma and examination findings of bilateral arteriolar tortuosity and unilateral paracentral acute middle maculopathy. RESULTS: Work-up revealed anemia and elevated serum viscosity. Protein electrophoresis demonstrated an immunoglobulin M kappa monoclonal protein spike, and bone marrow biopsy confirmed an immunoglobulin M gammopathy consistent with Waldenström macroglobulinemia. Systemic chemotherapy was initiated. CONCLUSION: This case demonstrates typical optical coherence tomography findings of paracentral acute middle maculopathy, which led to the diagnosis of a rare lymphoproliferative disorder. This highlights the importance of a prompt work-up for paracentral acute middle maculopathy to detect underlying systemic diseases, including hyperviscosity syndromes.

The Histopathology of Cold Agglutinin Disease-Associated B-Cell Lymphoproliferative Disease.

OBJECTIVES: Primary cold agglutinin disease is a type of autoimmune hemolytic anemia caused by circulating antibodies against I antigen, a carbohydrate expressed on most cells, including red blood cells. The underlying disease has been characterized in recent years as a distinct B-cell lymphoproliferative disease of the bone marrow, occurring mostly in the elderly. The disease has been now been included as a separate entity in the most recent classifications of mature B-cell neoplasms. METHODS: A review of the characteristics of cold agglutinin disease is provided, with an emphasis on the pathology features. RESULTS: A detailed description of the histopathology, immunophenotype, and genetics of cold agglutinin disease is provided and compared to other B-cell lymphoproliferative diseases in the bone marrow with similar features. CONCLUSIONS: Recognition of the pathology features of cold agglutinin disease allows to distinguish it from other diseases, especially lymphoplasmacytic lymphoma and marginal zone lymphoma.

Waldenström macroglobulinemia with secondary pure red cell aplasia in a patient with metastatic castrate resistant prostate cancer receiving an immune checkpoint inhibitor: a case report.

BACKGROUND: Hypoproliferative anemia is a frequently encountered adverse event in cancer patients receiving immune checkpoint inhibitors (ICI). Secondary pure red cell aplasia (PRCA) is a rare but recognized immune related adverse event. With the burgeoning use of ICIs, the association of secondary PRCA with an underlying lymphoproliferative disorder is often overlooked. CASE PRESENTATION: We report a case of a 67-year-old non-Hispanic Caucasian male with metastatic castrate resistant prostate cancer, who developed severe transfusion dependent anemia with reticulocytopenia while receiving treatment with olaparib and pembrolizumab. His bone marrow findings demonstrated erythroid hypoplasia, in addition to a CD5-negative, CD10-negative monotypic B-cell population and a somatic MYD88L265P mutation. With a presence of an IgM-paraprotein, he was diagnosed with Waldenström macroglobulinemia (WM) with secondary PRCA and treated with 6 cycles of bendamustine and rituximab. He achieved a complete response with this regimen and was transfusion independent. CONCLUSION: In this case, underlying WM was uncovered through systematic investigation of anemia caused by ICI therapy. This report highlights the possibility of a lymphoproliferative disorder in patients with concerns for PRCA with prior ICI exposure. If identified, treating the underlying lymphoproliferative disorder is highly efficacious in the management of the secondary PRCA.

Report of Consensus Panel 6 from the 11 th International Workshop on Waldenström's Macroglobulinemia on Management of Waldenström's Macroglobulinemia Related Amyloidosis.

Consensus Panel 6 (CP6) of the 11th International Workshop on Waldenström's Macroglobulinemia (IWWM-11) was tasked with reviewing the state of the art for diagnosis, prognosis, and therapy of AL amyloidosis associated with Waldenström macroglobulinemia (WM). Since significant advances have been made in the management of AL amyloidosis an update for this rare disease associated with WM was necessary. The key recommendations from IWWM-11 CP6 included: (1) The need to improve the diagnostic process by recognizing red flags and using biomarkers and imaging; (2) The essential tests for appropriate workup; (3) The diagnostic flowchart, including mandatory amyloid typing, that improves the differential diagnosis with transthyretin amyloidosis; (4) Criteria for therapy response assessment; (5) State of the art of the treatment including therapy of wild type transthyretin amyloidosis associated with WM.

Peripheral neuropathy as clinical onset of monoclonal IgM/k-related amyloidosis.

AIM: Neuropathy is a frequent complication of Waldenström's macroglobulinemia (WM), the most common being a demyelinating polyneuropathy with anti-myelin associated glycoprotein (MAG) antibodies, but also cryoglobulins, vasculitis, neurolymphomatosis, and amyloidosis. We describe a patient with IgM/kappa WM who presented with a severe, not length-dependent, peripheral neuropathy as clinical onset of IgM/kappa-related amyloidosis. METHODS: A 69-year-old woman came to our attention for weight loss, gait imbalance and sensory loss at upper limbs. In her medical history, she was in hematological follow-up for WM, and had undergone left carpal tunnel release. At neurological evaluation she had weakness and loss of sensation at upper limbs up to the elbows, more at the left side, gait was unsteady with right foot drop. Hypotrophy and areflexia were present at four limbs. Sensory loss and vibration sense were dramatically reduced. She underwent extensive diagnostic workup. RESULTS: Laboratory workup revealed an IgM/kappa monoclonal paraprotein of 16 g/L and increased NT-proBNP; anti-MAG antibodies were absent. Bone marrow biopsy demonstrated a population of neoplastic B-lymphocytes. Total-body CT scan and echocardiogram were negative. Neurophysiology revealed a symmetric, no length dependent sensory-motor polyneuropathy Periumbilical fat biopsy was positive for amyloid. Sural nerve biopsy detected amyloid in the wall of an epineurial vein. CONCLUSIONS: This case report describes a rare and unusual manifestation of IgM-related AL amyloidosis in WM. The patient presented with a subacute clinically asymmetric neuropathy with no pain or dysautonomic features as clinical onset of IgM/kappa-related amyloidosis. Sural nerve biopsy was crucial for the diagnosis.