A Plasmacytoma of the Lateral Pharyngeal Wall: A Diagnostic Enigma.

Plasmacytoma is a rare plasma cell dyscrasia that grows in bones or soft tissues such as the pharynx. Soft tissue plasmacytomas are rare, and a higher burden has been reported in the upper aero-digestive tract, often manifesting as hoarseness, dysphagia, or odynophagia. Due to their rarity, extramedullary plasmacytomas (EMPs) have unknown prognostic factors, and guidelines for optimal management are still lacking. However, radiation therapy and surgery have been used with positive outcomes. Herein, we describe a unique case of plasmacytoma of the pharyngeal tissue in a male patient with a history of HIV disease. The patient completed 28 sessions of radiation therapy, resulting in an improvement in his throat pain and hoarseness. Given the patient's age and lack of traditional risk factors for head and neck cancers, his hoarseness and odynophagia proved to be a diagnostic conundrum. Although infrequent, soft tissue plasmacytomas should be considered in the differential diagnosis of head and neck tumors.

[Consensus for the diagnosis and management of extramedullary plasmacytoma in China(2024)].

Extramedullary plasmacytoma (EMP) is a special type of malignant plasmacytosis, which is complex and heterogeneous. Most EMP patients have poor prognosis and lack a stratified prognostic system or ideal treatment strategy supported by evidence-based medical evidence, which cannot meet clinical needs. In order to improve the understanding of this disease entity, Plasma Cell Disease Group, Chinese Society of Hematology, Chinese Medical Association and Chinese Myeloma Committee-Chinese Hematology Association developed the "Chinese Expert Consensus on the diagnosis and treatment of extramedullary plasmacytoma", which aims to standardize the clinical diagnosis and treatment of EMP and ultimately improve the overall survival of patients with plasmacytoma.

Skeletal muscle extramedullary plasmacytoma transformed into plasmablastic plasmacytoma: a case report.

BACKGROUND: Extramedullary plasmacytoma (EMP) is a rare plasma cell malignancy, especially when the tumor originates in skeletal muscle. Plasmablastic plasmacytoma is an anaplastic round cell tumor with highly malignancy and poor prognosis. To date, there have been no reports on the transformation of skeletal muscle EMP into plasmablastic plasmacytoma. Therefore, the diagnosis, treatment, and prognosis of cases of this pathologic transformation are unclear. CASE PRESENTATION: This article reports a case of an elderly male patient who presented with a painless mass in the right calf and was diagnosed with EMP by puncture pathology. Complete remission was obtained after sequential chemoradiotherapy. 6 months later, another puncture was performed due to plasmablastic plasmacytoma multiple distant metastases, and the pathology showed that EMP was transformed to plasmablastic plasmacytoma. Despite aggressive antitumor therapy, the disease continued to deteriorate, and the patient ultimately died of respiratory failure. CONCLUSION: The transformation of EMP into plasmablastic plasmacytoma is very rare, and its diagnosis and treatment require the participation of both experienced pathologists and clinicians. We report this case in order to raise clinicians' awareness of the diagnosis and treatment of EMP and its transformation to plasmablastic plasmacytoma, and to avoid misdiagnosis and underdiagnosis.

Extramedullary Plasmacytoma of the Penis as a First Manifestation of Multiple Myeloma: A Case Report.

INTRODUCTION: Plasmacytoma is a rare plasma-cell neoplasm, which includes bone and extramedullary types. While most cases occur in the head and neck, our report presents an unusual case of extramedullary plasmacytoma (EMP) in the penis, emphasizing the diverse locations of this condition. CASE PRESENTATION: An 88-year-old man, post-hydrocelectomy, presented with a palpable penile mass causing urinary symptoms. CT scans revealed a tumor with extracapsular spread and potential urethral involvement. Biopsy confirmed lymphoma, later identified as extramedullary plasmacytoma. A follow-up whole-body CT scan was performed, revealing multiple areas of bone rarefaction of the dens of the axis. His diagnosis has been further specified as multiple myeloma. Treatment with lenalidomide, bortezomib, and dexamethasone led to significant penile tumor reduction and improved voiding symptoms after three cycles. CONCLUSION: A rare case of primary EMP in the penis is reported, with only two documented cases of EMP in this location. The etiology of EMP remains unclear, possibly linked to chronic infection, irritation, or inflammation. EMP typically occurs in soft tissues, commonly in the head and neck, presenting as submucosal masses with symptoms in individuals aged 50-70. Diagnosis requires demonstrating monoclonal plasma cell infiltration and excluding multiple myeloma. While EMPs are often treated with radiotherapy, a patient with bone rarefaction suggestive of multiple myeloma requires first-line chemotherapy. This case highlights the importance of recognizing myeloma-defining events for appropriate treatment.

Adenopathy and an Extensive Skin Patch Overlying a Plasmacytoma Syndrome.

This case report describes a central cobblestone-like mass and bone lesion on the spinous process of the L3 vertebra underlying the skin mass.

Renal AA amyloidosis revealing extramedullary plasmocytoma / Amylose rénale AA révélant un plasmocytome extra-médullaire : étude de cas

Introduction: Solitary plasmacytoma is a rare, localized malignancy. Bone localizations are the most common. Extramedullary plasmacytomas are much rarer. They are most often in the upper respiratory tract and can be complicated by amyloidosis. Here is an original report of a mediastinal extramedullary plasmacytoma revealed by type AA renal amyloidosis. Case presentation: We present the case of a 52-year-old patient with mediastinal extramedullary plasmocytoma diagnosed by renal failure due to type AA renal amyloidosis. Treatment was based on surgery with chemotherapy based on prednisone and melphalan. The patient presented end-stage renal failure that required hemodialysis at discharge. Conclusion: Extramedullary plasmacytoma is a rare tumour that may be associated with amyloidosis, usually type AL. To our knowledge, its association with AA amyloidosis has not been reported in the literature. Treatment is based on surgery combined with radiotherapy or chemotherapy.

Introduction: Le plasmocytome solitaire est une tumeur maligne rare localisée. Les localisations osseuses sont les plus fréquentes. Les plasmocytomes extra­médullaires (PEM) sont beaucoup plus rares, localisés le plus souvent au niveau des voies respiratoires supérieures. Présentation du cas: Nous rapportons une observation de PEM médiastinal révélé par une insuffisance rénale en rapport avec amylose rénale de type AA chez un patient âgé de 52 ans. Le traitement a comporté une tumorectomie de la masse associée à une chimiothérapie. Sur le plan rénal, le patient était au stade d'insuffisance rénale terminale nécessitant le recours à l'hémodialyse chronique. Conclusion: Le PEM est une tumeur rare pouvant se compliquer d'une amylose le plus souvent de type AL. Son association à une amylose AA n'a pas été rapportée auparavant à notre connaissance. Le traitement est basé surtout sur la chirurgie associée à une radiothérapie ou chimiothérapie.

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.

Hematological entities with plasmacytic differentiation: a case report.

INTRODUCTION: Plasmacytoma, a localized tumor of monoclonal plasma cells without any clinical, radiological or physical evidence of plasma cell neoplasm (PCN), is a rare entity that accounts for 1% of PCN. Immunoglobulin M (IgM) extramedullary plasmacytoma of mediastinal region has never been reported and is a diagnostic challenge considering other differential diagnoses. CASE PRESENTATION: We present the case of a 51-year-old African-American female with progressively increasing cough, dyspnea, and dysphagia for 6 months with a computed tomography (CT) scan revealing a subcarinal mass. The histopathological analysis of the mass reveals a diagnosis of lymphoma with plasma cell differentiation, with a differential of lymphoplasmacytic lymphoma and plasma cell neoplasm. The lymphoma panel via next-generation sequencing (NGS) and a myeloma-targeted fluorescent in situ hybridization (FISH) panel confirmed the diagnosis of IgM extramedullary plasmacytoma, an entity of rare occurrence. Treatment with radiation led to complete regression of the plasmacytoma with normal blood work-up. CONCLUSIONS: This report describes the challenges of diagnosing IgM extramedullary plasmactyoma. Our case report highlights the importance of cytogenetics and NGS in establishing a correct diagnosis that indeed has prognostic and therapeutic implications.

Distal Chronic Inflammatory Demyelinating Polyneuropathy Following COVID-19 Vaccination in a Patient with Solitary Plasmacytoma: A Case Report and Literature Review.

We herein report a rare case of distal chronic inflammatory demyelinating polyneuropathy (CIDP) following coronavirus disease 2019 (COVID-19) vaccination. A 39-year-old woman with a solitary plasmacytoma developed general weakness 7 days after receiving the second dose of the Pfizer-BioNTech COVID-19 vaccine, which had progressed for 3 months. A neurological examination revealed limb weakness with areflexia. Serological tests identified the presence of IgG antibodies against anti-GM1 and anti-GM2 gangliosides. Comprehensive evaluations met the criteria of distal CIDP. Intravenous immunoglobulin, intravenous methylprednisolone, oral prednisolone, and plasma exchange were administered, and she gradually improved. Physicians should be aware of CIDP as a rare complication of COVID-19 vaccination.

Rapidly Enlarging Parotid Mass in a Person Living with HIV: A Case of Multiple Myeloma with Extramedullary Plasmacytoma.

BACKGROUND The differential diagnosis for a parotid mass is broad, including infectious, autoimmune, and neoplastic etiologies. In people with HIV, regardless of viral suppression or immune status, neoplastic causes are more common. This report describes the evaluation of a woman with a large parotid mass, with an ultimate diagnosis of multiple myeloma with extramedullary plasmacytoma. CASE REPORT A 51-year-old woman with HIV infection presented with headache, weight loss, and right facial mass that was present for 5 years but more rapidly enlarging in the prior year. CD4 count was 234 cells/mL, and HIV RNA was 10 810 copies/mL. Physical examination was significant for a large deforming right-sided facial mass, decreased sensation in the V1 and V2 distributions, and right-sided ophthalmoplegia and ptosis. MRI and PET/CT scan confirmed a metabolically active large parotid mass with extension into the cavernous sinus. An IgG kappa monoclonal spike was present on serum protein electrophoresis. Incisional biopsy of the facial mass showed atypical lymphoid cells with plasmablastic and plasmacytic morphology with a high mitotic rate and proliferation index. She was diagnosed with R-ISS stage II IgG kappa multiple myeloma with extramedullary plasmacytoma, and initiated on chemotherapy, radiation, and antiretroviral therapy. CONCLUSIONS A rapidly enlarging parotid mass should prompt timely evaluation and biopsy for definitive diagnosis, particularly in immunocompromised patients, including people with HIV. Extramedullary plasmacytomas have a more aggressive disease process in people with HIV and are associated with high-risk multiple myeloma and progression, as seen in this patient.

Epidemiology and survival of primary extraosseous plasmacytoma: insights from a population-based study with a 20-year follow-up.

Primary extraosseous plasmacytoma (PEP) is a rare and localized form of plasmacytoma that is not well understood. This study aimed to investigate the clinical features and prognostic factors associated with PEP. Using the Surveillance, Epidemiology, and End Results (SEER) database, a total of 1044 patients diagnosed with PEP between 2000 and 2019 were identified. The average age was 60.3 ± 15.2 years, with 64.3% being male (male: female = 1.8:1) and 53.8% being over 60-year old. The survival outcome of patients with PEP depends on several factors including age, race, marital status, and treatment options such as chemotherapy, radiotherapy, and surgery, which were also identified as independent predictors of overall survival for PEP. Patients who were younger, Asian or Pacific Islander, American Indian or Native American, and received radiotherapy or surgery had a more favorable prognosis, while those who underwent chemotherapy had poorer outcomes.

Amyloidoma and Plasmacytoma Presented as a Solitary Lung Nodule in a Patient of Multiple Myeloma With AL-Amyloidosis: A Case Report and Review of Literature.

Nodular amyloidoma in the lungs is a rare entity, also the occurrence of extramedullary plasmacytoma (EMP) in the lungs is rare. To have concomitant EMP and amyloidoma presented as a single lung mass is even rarer. There was only one similar case reported in the abstract form previously. Our case did not respond to many novel chemotherapy agents, suggesting that this combination of amyloidoma and plasmacytoma belonged to a poor prognosis entity, requiring different treatment modalities, such as early bone marrow transplantation or CART (chimeric antigen receptors T) therapy.

Plasmacytoma of the Head and Neck: Case Series and Review of the Literature.

Solitary plasmacytoma is a rare neoplasm characterized by localized proliferation of monoclonal plasma cells and is classified as solitary bone or solitary extramedullary plasmacytoma. Here, we present two rare cases of plasmacytoma of the head and neck. The first is a 78-year-old male who presented with a 3-month history of epistaxis and progressive obstruction of the right nasal passage. Computerized tomography (CT) imaging revealed a mass in the right nasal cavity with destruction to the maxillary sinus. An excisional biopsy was performed revealing anaplastic plasmacytoma. The second is a 64-year-old male with a past medical history significant for prostate cancer who presented with a 2-month history of left ear pain and progressive non-tender temporal swelling. A PET/CT revealed a highly avid, destructive, and lytic left temporal mass with no other evidence of distant disease. A left temporal craniectomy and infratemporal fossa dissection revealed plasma cell dyscrasia with monoclonal lambda in situ hybridization. Although plasmacytomas are uncommon tumors of the head and neck, they may mimic other entities that require different treatment. Prompt and accurate diagnosis is critical for appropriate therapeutic decisions and prognosis.

Ovarian plasmacytoma: a case report.

Plasmacytomas are a rare spectrum of plasma cell neoplasms that are single localized tumours, lacking the clinical features of plasma cell myeloma with no radiographical evidence of additional plasma cell tumours. Two clinical variants of plasmacytomas can be distinguished: solitary plasmacytoma of bone and extramedullary (or extraosseous) plasmacytoma. The latter is rare, representing 1% of all plasma cell neoplasms, occurring most frequently in the upper airways. Ovarian localization is exceptional, with only a few cases being reported in the literature. We herein report a case of an ovarian extramedullary plasmacytoma occurring in a 56-year-old woman who consulted for abdominal pain and abdominal mass, while highlighting the main histological and immunohistochemical features of this rare malignancy, along with a thorough review of literature gathering all cases of ovarian plasmacytomas reported to date.

Multiple myeloma presenting as blepharitis in a horse.

Myeloma-related disorders, including multiple myeloma, extramedullary plasmacytoma, and solid osseous plasmacytoma, are rare in horses. Clinical complaints for myeloma-related disorders are nonspecific, and when present, M-protein location is more variable on protein electrophoresis in horses relative to dogs and cats. Here, we describe a case of a 15-year-old Thoroughbred mare who presented with recurrent blepharitis. Marked hyperglobulinemia was an incidental finding on routine hematologic and biochemical testing. Bone marrow aspiration consisted of >30% plasma cells, and serum protein electrophoresis demonstrated a monoclonal gammopathy in the alpha 2 fraction leading to a diagnosis of multiple myeloma. Immunofixation and radial immunodiffusion confirmed the presence of an IgG M-protein. Based on a restricted peak in the alpha 2 location, the specific M-protein is suspected to be IgG(T), an IgG isotype unique to horses. M-protein migration in horses is variable relative to dogs and cats, yet immunofixation can still be used to identify equine IgG M-protein isotypes. The unique clinical presentation in this case also serves as a reminder to consider neoplasia in horses with unusual or nonspecific clinical signs.