Renal plasmacytoma: Report of a rare case and review of the literature

Renal Riddles Unveiled: Decoding Homogeneous Kidney Enlargement in Multiple Myeloma

Renal plasmacytoma is a rare extramedullary manifestation of plasma cell neoplasms (PCN). We present the case of a 62-year-old male with a history of relapsed refractory multiple myeloma (MM) who developed secondary renal plasmacytoma after an eight-year remission period. Radiological findings on plain CT raised concern for the most common renal malignancy, i.e. renal cell carcinoma (RCC), while further imagining evaluation with MRI suggested renal lymphoma, highlighting the diagnostic challenge of renal plasmacytoma on imagining. A renal mass biopsy confirmed a kappa-restricted plasma cell tumor, emphasizing the need for accurate differentiation between renal plasmacytoma and other renal malignancies to guide appropriate treatment strategies. Increased awareness of such cases can lead to timely recognition and tailored management for this rare entity.

Direct infiltration of clonal plasma cells causes renal insufficiency in patients with monoclonal gammopathy of undetermined significance

Monoclonal gammopathy of undetermined significance (MGUS) is a benign but precancerous condition that can progress to multiple myeloma. Patients with MGUS are typically monitored closely for signs of disease progression, but in some cases, they may also develop renal insufficiency, a condition known as monoclonal gammopathy of renal significance (MGRS). In MGRS, M-protein secreted by a nonmalignant or premalignant cell clone triggers renal damage by definition. Herein, we report a case of a 66-year-old Asian male with MGUS complicated by renal insufficiency. A kidney biopsy showed no evidence of renal injury mediated by M-protein; instead, the direct infiltration of clonal cells into renal tissues was observed. Although five similar cases have been previously reported, our case is unique in that the involvement of clonal cells was directly confirmed by fluorescence in situ hybridization. Our findings suggest the need to consider a novel disease concept, as this phenomenon appears to be reproduced.

Extramedullary plasmacytoma of the oral cavity metastasising to both kidneys in a dog

BACKGROUND

Most extramedullary plasmacytomas (EMPs) aresolitary and located in the head and neck region. They may also occur in the visceral parts of the body.

OBJECTIVES

Here, we report a case of oral EMP followed by neoplastic plasma cell metastasis to both kidneys in a neutered male Pomeranian.

METHODS

Oral plasmacytoma recurred 11 months aftersurgical removal of an oral mass and partial maxillectomy was performed. Eighteen months after partial maxillectomy, neoplastic masses were detected in both kidneys on computed tomography. The dog died 12 months after detection of bilateral kidney neoplasms. The resected neoplastic masses were routinely processed for histopathological observation and immunohistochemistry against pan-cytokeratin, desmin, CD3, and MUM-1.

RESULTS

The recurred mass mainly consisted of well-differentiated plasma cells and contained a small portion of aggressive cells with malignant features. Monoclonal gammopathy was not observed on serumelectrophoresis performed to exclude multiple myeloma. The mass was composed of plasma cells with high nuclear pleomorphism and abundant mitotic figures. The neoplasm stained positive for MUM-1 with a more aggressive morphology than in oral EMP.

CONCLUSION

Based on serum biomarker and pathological observations, a diagnosis of recurrence and metastasis of oral-to-renal EMP was established. To the best of our knowledge, metastasis of oral EMP into the bilateral kidneys, as described in the current case, has not been previously reported in dogs.

Refractory primary extramedullary plasmacytoma in kidney: a case report

Extramedullary plasmacytoma (EMP) is a rare plasma cell neoplasm, with the majority (80–90% of cases) occurring in the upper aerodigestive tract. To our best knowledge, primary EMP from renal tissues is extremely rare. Herein, the diagnosis and treatment of a refractory primary EMP with renal involvement in a 53-year-old male patient is reported. The patient received radical nephrectomy followed by radiotherapy, and showed relapse 3 months after treatment. The cancer cells were sensitive to subsequent chemotherapy, however, the patient died of infection associated with the disease after almost 3.5 years following first presentation.

Renal extramedullary plasmacytoma in a dog

A 10-year-old, intact male Siberian husky dog was presented for a suspected left renal cyst. Computed tomography (CT) identified a large, left kidney mass with retroperitoneal hemorrhage. A left-sided nephrectomy was performed, and histopathology confirmed a renal plasmacytoma. Perioperative screening for multiple myeloma was negative. The dog was lost to follow-up and was euthanized 11 months after surgery. A necropsy was not performed. To the authors' knowledge, this is the first case of renal extramedullary plasmacytoma in a dog. Key clinical message: This report describes the clinical presentation, and laboratory, diagnostic imaging, and surgery findings of a case of renal extramedullary plasmacytoma in a dog.

A 64-year-old woman with rapid neurologic decline diagnosed with Toxoplasma encephalitis after presumed metastatic cancer

In an era of fragmented medical care, concurrent clinical features that ultimately lead to a unified diagnosis may not be prioritized appropriately. We present a case of a 64-year-old woman referred to hematology clinic for anemia, with recent memory loss and gait disturbance. Two months later, she developed pneumonia; imaging workup showed a left renal mass. Neurologic function continued to decline precluding definitive nephrectomy. She then presented with new-onset seizure and initial neuro-imaging was reported as unremarkable. One month later, outpatient neurologic workup demonstrated new left-sided weakness which prompted hospitalization and repeat neuro-imaging, which showed a 1.7-cm right frontal lobe mass lesion with surrounding vasogenic edema. The patient ultimately underwent craniotomy with resection of the mass lesion; pathology did not show metastatic renal cell cancer, the provisional clinical diagnosis. Rather, immunostaining revealed a parasite and ultimately led to a diagnosis of Toxoplasma encephalitis, an infection whose clinical presentation had been interpreted by healthcare providers for months to be a result of metastatic cancer.

Monotypic plasma cell interstitial nephritis as the only clinical manifestation in a patient with previously undiagnosed indolent multiple myeloma: A case report

INTRODUCTION

Predominantly monotypic plasma cell infiltrates are an uncommon renal finding in patients with malignant lymphoplasmacytic proliferation.

CASE PRESENTATION

We report the case of a 52-year-old man with chronic kidney disease and significant proteinuria associated with a monoclonal immunoglobulin spike (IgGκ). Kidney biopsy revealed the presence of atypical multinucleated CD138 plasma cells with voluminous nuclei stained exclusively with a κ antibody. Electron microscopy showed mesangial and segmental parietal electron-dense, nonorganized hyaline deposits without immunogold labeling for the κ light chain. The bone marrow aspirate revealed 6% of apparently mature plasmocytes without dystrophy. We therefore concluded that the patient had an indolent multiple myeloma with specific renal involvement in the form of malignant monotypic interstitial plasmacytic infiltration. We initiated a specific chemotherapy regimen including bortezomib-cyclophosphamide-dexamethasone. After 4 months of follow-up, creatinine levels had improved slightly and free κ light-chain levels had decreased significantly within the normal range.

CONCLUSION

This case highlights the need to consider neoplastic interstitial plasma cell infiltration systematically in patients diagnosed with an apparently benign monoclonal gammopathy and to consider adaptation of the chemotherapy regimen, to improve renal function.

Collision Tumor With Renal Cell Carcinoma and Plasmacytoma: Further Evidence of a Renal Cell and Plasma Cell Neoplasm Relationship?

Renal solitary extramedullary plasmacytomas belong to a group of plasma cell neoplasms, which generally have been associated with renal cell carcinoma. We present a case report of a patient with collision tumor histology of extramedullary plasmacytoma and clear cell renal cell carcinoma, the first in the known literature. Standard work-up for a plasma cell neoplasm was conducted and the mass was resected. The patient remains disease-free at 28 months post-surgery. The report calls into question pre-surgical renal mass biopsy protocol and suggests a relationship between renal cell carcinoma and plasma cell neoplasms.

Irradiation combined with surgery for function preservation in the treatment of extramedullary plasmacytoma of the left labia majora during pregnancy: A case report

Extramedullary plasmacytoma (EMP) in the vulva is extremely rare. The current study presents, for the first time, a case of EMP in the left labia majora in a 36-year-old patient during pregnancy. A painful 7×4×2-cm mass with ulceration, pus and blood scabs, previously misdiagnosed as vulvar ulcer in a local hosipital, was proven to be an EMP by biopsy. Upon magnetic resonance imaging, the tumor was shown to occur in the left labia majora without lymphadenopathy. A complete multiple myeloma (MM) workup excluded coexistence with MM. The goal of treatment was to eradicate the tumor while synchronously preserving the vulva. Therefore, following the termination of the pregnancy, radiotherapy with a total dose of 4,500 cGy markedly reduced the size of the tumor. An extended local excision of the residual tumor, and anaplasty of the vulva preserved the appearance and function of the vulva to the utmost. No post-operative radiation was administered, as the resection margins were not microscopically involved. There was no relapse, metastasis or progression to MM in a 9-month post-operative follow-up period, but close follow-up and long-term surveillance are required.

Multiple myeloma with intracranial extension and bilateral renal infiltration: A case report and review of the literature

Multiple myeloma (MM) is a rare hematological malignancy, characterized by uncontrolled proliferation of plasma cells in the bone marrow. MM is usually confined to the bone marrow, however, it may occasionally infiltrate other tissues, which is known as extramedullary plasmacytoma (EMP). The majority of EMPs involve the head and neck region, although different anatomical sites, including the gastrointestinal tract, central nervous system, thyroid gland and breast may also be affected. The simultaneous presentation of EMP in the kidney and head is rare, presenting diagnostic challenges due to its unusual location and non-specific or absent symptoms. To the best of our knowledge, no case of extramedullary plasmacytoma presenting with simultaneous renal and intracranial infiltration has been reported in the literature thus far. However, the present study reports a case of primary renal and intracranial extramedullary plasmacytoma in a 76-year-old male patient. The patient presented with a swelling over the right side of the forehead, which had slowly increased in size prior to hospital admission. The swelling was associated with dizziness and weakness, without bone pain. Contrast magnetic resonance imaging suggested an osteolytic skull lesion with intracranial extension. Abdominal enhanced computed tomography scanning revealed a large tumor mass extending around and into the kidneys. Immunohistochemical examination of the renal tumor biopsy, and blood and serum samples, as well as immunoelectrophoresis of serum proteins, resulted in a diagnosis of EMP being proposed. Therefore, the patient was administered with two cycles of cyclophosphamide and thalidomide in combination with dexamethasone. Follow-up imaging performed 4 months later revealed almost complete disappearance of the intracranial tumor mass and renal infiltration. The current study also presented a review of the literature. This study revealed that EMPs may co-exist with MM or present as the main symptom of MM. The diagnosis of an EMP is complex and requires radiological, hematological, biochemical and histological investigation. At present, no guidelines for EMP treatment have been established and thus, treatment options include surgery, chemotherapy and radiotherapy, either alone or in combination. We hypothesize that combined treatment may provide the best patient outcome.

A case of disseminated recurrent retroperitoneal plasmacytoma with left obstructive hydronephrosis

Retroperitoneal extramedullary plasmacytoma (EMP) is a rare condition that often poses a diagnostic challenge. This is mainly due to its unusual location and non-specific symptoms especially in its early stages. Retroperitoneal plasmacytoma with renal involvement is an extremely rare entity and to date, less than 25 cases have been reported in the literature. We describe a case of a 65-year-old woman with primary retroperitoneal plasmacytoma, confirmed by ultrasound-guided biopsy and histopathological examination, with unilateral left obstructive hydronephrosis and metastasis to the lungs. Our patient was started on chemotherapy to which she did not respond. Subsequently, she resorted to palliative measures. Our case highlights key aspects of clinical presentation, diagnosis and treatment options available for management of retroperitoneal plasmacytoma.