A case of autoimmune encephalitis in a patient with a solitary intracranial plasmacytoma.

A 65-year-old woman presented with fever and abnormal behavior. Magnetic resonance imaging showed swelling of the left medial temporal lobe and an intracranial extra-axial occipital tumor. While her neurological symptoms improved after the administration of corticosteroid therapy under the suspicion of autoimmune encephalitis, the occipital tumor unexpectedly shrank, and the diagnosis of a solitary plasmacytoma was confirmed by biopsy. Additional examinations revealed elevated anti-glutamate receptor antibodies in the cerebrospinal fluid. The patient was diagnosed with autoimmune encephalitis concurrent with an intracranial solitary plasmacytoma. Central nervous system involvement can be considered a neurological complication in patients with a solitary plasmacytoma.

Development and validation of a machine learning-based postoperative prognostic model for plasma cell neoplasia with spinal lesions as initial clinical manifestations: a single-center cohort study.

BACKGROUND: Spinal multiple myeloma (MM) and solitary plasmacytoma of bone (SPB), both plasma cell neoplasms, greatly affect patients' quality of life due to spinal involvement. Accurate prediction of surgical outcomes is crucial for personalized patient care, but systematic treatment guidelines and predictive models are lacking. OBJECTIVE: This study aimed to develop and validate a machine learning (ML)-based model to predict postoperative outcomes and identify prognostic factors for patients with spinal MM and SPB. METHODS: A retrospective analysis was conducted on patients diagnosed with MM or SPB from 2011 to 2015, followed by prospective data collection from 2016 to 2017. Patient demographics, tumor characteristics, clinical treatments, and laboratory results were analyzed as input features. Four types of ML algorithms were employed for model development. The performance was assessed using discrimination and calibration measures, and the Shapley Additive exPlanations (SHAP) method was applied for model interpretation. RESULTS: A total of 169 patients were included, with 119 for model training and 50 for validation. The Gaussian Naïve Bayes (GNB) model exhibited superior predictive accuracy and stability. Prospective validation on the 50 patients revealed an area under the curve (AUC) of 0.863, effectively distinguishing between 5-year survivors and non-survivors. Key prognostic factors identified included International Staging System (ISS) stage, Durie-Salmon (DS) stage, targeted therapy, and age. CONCLUSIONS: The GNB model has the best performance and high reliability in predicting postoperative outcomes. Variables such as ISS stage and DS stage were significant in influencing patient prognosis. This study enhances the ability to identify patients at risk of poor outcomes, thereby aiding clinical decision-making.

Combined endoscopic transorbital and transnasal approach for the management of a solitary plasmacytoma of the sphenoid bone: A case report and literature review.

Background: Parasellar plasmacytomas are rare neurosurgical entities. Intrinsic characteristics of these tumors, such as adjacent bone erosion and symptoms resulting from invasion and mass effect, may lead to the possibility of a solitary extramedullary plasmacytoma (SEP) as a differential diagnosis. Case Description: We present the case of a 39-year-old male with a 1-month history of bilateral decreased visual acuity, retroocular pulsating pain, and chromatic vision loss. A computed tomography scan of the head revealed a parasellar lesion causing chiasmatic compression, as well as clival, orbital, sphenoidal, and ethmoidal invasion. A combined transorbital and endonasal endoscopic approach was found suitable, and gross total resection was achieved. Histological analysis of the lesion established the diagnosis of a SEP. After radiotherapy, a new magnetic resonance imaging was performed, revealing a recurrence of the lesion with a high grade of invasion. The patient was treated with palliative radiotherapy, as surgical resection did not seem feasible. Conclusion: Surgical resection and radiotherapy may achieve remission of these lesions; however, recurrence rates remain high despite any treatment modality. Patients with this condition must be followed up with a multidisciplinary team due to the high risk of multiple myeloma progression.

Solitary Plasmacytoma of the Breast: A Rare Entity.

Solitary plasmacytoma of the breast is an extremely rare neoplastic entity characterized by the localized proliferation of neoplastic plasma cells within the breast tissue that requires careful consideration due to its clinical and radiological resemblance to more common breast malignancies. While plasmacytomas are typically associated with multiple myeloma (MM), primary involvement of the breast as a solitary lesion is exceptionally rare. In this report, we present a case of solitary plasmacytoma of the breast in a 55-year-old female patient who presented with a palpable breast mass and no signs of systemic multiple myeloma. Our objective is to discuss the clinical presentation, radiological features, and histopathological findings and highlight the importance of comprehensive diagnostic workup and management planning for solitary plasmacytomas of the breast.

Solitary plasmacytoma of the calvarium: A successful management of a long-standing large lesion with a long-term follow-up.

Background: Solitary plasmacytoma of the calvarium (SPC), without evidence of multiple myeloma (MM), is extremely rare. We report a case of a long-standing large SPC that was treated successfully by surgical excision and adjuvant radiotherapy with a long follow-up period. Case Description: A 58-year-old male patient presented with a 5-year history of painless skull swelling. On the physical examination, the mass was 6 × 6 cm in size, oval, not tender, and firm in consistency with normal skin color. A brain computed tomography scan showed a destructive skull lesion. A brain magnetic reasoning imaging (MRI) showed a large expansile lytic mass lesion arising from the skull vault in the frontal-parietal region with multiple internal septa. The patient underwent a craniectomy and excision of the lesion, followed by cranioplasty using methyl methacrylate. The final diagnosis was consistent with plasmacytoma based on the histopathological features. One month follow-up brain MRI showed no evidence of residual tumor. The skeletal survey and bone marrow biopsy did not reveal any evidence of MM. The patient was referred to medical oncology for further treatment and received radiation therapy. During nine years of clinical and radiological follow-up, there was no evidence of any metastasis or recurrence. Conclusion: SPC is a rare disease with high rates of misdiagnosis. Careful evaluations are crucial to exclude systemic involvement. Surgical resection followed by radiotherapy may be adequate for the disease control. Close follow-up with regular lifelong examinations is important to avoid a generalized incurable disease.

Spinal Solitary Plasmacytoma With Minimal Marrow Involvement Presenting With Epidural Spinal Cord Compression.

Solitary plasmacytoma (SPC) is a rare type of plasma cell dyscrasia characterized by the proliferation of neoplastic monoclonal plasma cells. It can involve bone or soft tissue without signs of systemic disease. The solitary bone plasmacytoma typically involves the axial skeleton, most commonly the vertebrae. This article presents a 58-year-old male with a history of Parkinson's disease, hypertension, and cervical spine degenerative joint disease. He arrived at the emergency department with severe thoracic and lumbar back pain, accompanied by numbness and weakness in both legs, which worsened with movement and deep breathing. Magnetic resonance imaging (MRI) findings revealed a sizable mass in the T11 vertebra, leading to thoracic spinal cord compression. Treatment included high-dose dexamethasone, and surgical intervention was undertaken. Subsequent pathology confirmed plasma cell dyscrasia. Radiotherapy and chemotherapy (lenalidomide and dexamethasone) were administered, resulting in no recurrence or new masses after two years. Solitary plasmacytoma is a rare disease with limited clinical trials due to the inability to accrue larger cohorts. Prompt diagnosis and staging of plasmacytomas, involving robust histopathological and radiographic methods, are needed to prevent further complications and possible progression to multiple myeloma. Radiation therapy is the primary treatment, with some studies showing the benefits of lenalidomide and dexamethasone. Further studies are needed to improve treatment options for these patients. This case report adds to the current literature the importance of a multidisciplinary approach to the treatment of SPC.

Transoral percutaneous radiofrequency ablation with a steerable needle and cementoplasty under CBCT and infrared augmented reality navigation system guidance for the treatment of a C1 solitary plasmacytoma: A case report.

We report a case of a 40-year-old female with a solitary plasmacytoma of the right transverse apophysis of C1 who underwent combined transoral ablation using a curved steerable needle and cementoplasty under CBCT and infra-red augmented reality navigation system. An imaging work-up revealed an osteolytic lesion determining partial collapse of the right lateral mass of C1 and involving the vertebral foramen. After a biopsy, that revealed a solid tissue consistent with plasmacytoma, it was decided to proceed with radiation therapy. Subsequent PET-CT restaging scans showed residual tumors treated with a transoral percutaneous approach, combining ablation and cementoplasty. This report evaluates the benefits of this combined procedure and the transoral approach, focusing on the advantages of steerable devices and navigation systems.

Solitary Plasmacytoma of the Spine in a Young Male and the Outcome of Inpatient Rehabilitation Stay.

Solitary plasmacytoma (SP) can be classified into two groups: a solid mass of neoplastic monoclonal plasma cells in bone, also called a solitary bone plasmacytoma (SBP), or less likely solitary extramedullary plasmacytoma (SEP) without any evidence of systemic disease of multiple myeloma. The diagnosis should be made by biopsy confirmation, revealing monoclonal plasma cell infiltration from the mass. The SBP usually affects the axial skeleton. Males have a higher incidence than females, as the ratio is 2/1, and the average age is 55. SP incidence usually increases with age. SBP has a significantly higher risk for progression to myeloma, usually within two years, and radiotherapy (RT) is the treatment of choice. Patients with acute declining neurologic dysfunction require urgent surgery before radiation therapy. We report a middle-aged man who presented with bilateral lower extremity weakness. Thoracic MRI with and without contrast revealed a large soft tissue and osseous mass centered at the T8 vertebral body with a large paravertebral extension, causing spinal cord compression at the T8-T9 level. The patient's clinical presentation, assessment, and rehabilitation management are discussed. Patients with this diagnosis are not properly diagnosed for approximately six months.

Solitary plasmacytoma of the skull base: A case report and literature review.

Plasmacytoma of the skull base is a rare entity. We present a case of sphenoid plasmacytoma in a 51-year-old woman who had nasal obstruction, intermittent epistaxis, headaches, decreasing visual acuity, and diplopia. Computed Tomography (CT) scan and magnetic resonance imaging (MRI) showed a large heterogeneous, expansile lesion measuring 75 mm × 54 mm, centered on the sphenoidal bone and the clivus. Biopsy confirmed the diagnosis of solitary plasmacytoma after ruling out systemic spread by the initial assessment. The patient was successfully managed by external beam radiotherapy and a complete response was obtained after 12 months of follow-up.

A case report: Bilateral reconstruction of C2 lateral masses with expandable titanium cages following axis (C2) solitary plasmacytoma resection with 2-year follow-up.

Background: Solitary plasmacytoma (SP) caused the collapse/destruction of the C2 vertebral body in a 78-year-old male. To provide sufficient posterior stabilization, the patient warranted lateral mass fusion to supplement the bilateral pedicle/screw rod instrumentation. Case Description: A 78-year-old male presented with neck pain alone. X-rays, computed tomography, and magnetic resonance studies documented C2 vertebral collapse with the complete destruction of both lateral masses. The surgery required a laminectomy (i.e., bilateral lateral mass resection), plus placement of bilateral expandable titanium cages from C1 to C3 to supplement the screw/rod occipitocervical (O-C4) fixation. Adjuvant chemotherapy and radiotherapy were also administered. Two years later, the patient remained neurologically intact and radiographically had no evidence of tumor recurrence. Conclusion: In patients with vertebral plasmacytomas and bilateral lateral mass destruction, posterior occipital-cervical C4 rod/screw fusions may warrant the additional bilateral placement of titanium expandable lateral mass cages from C1 to C3.

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.

Construction and Validation of a Novel Web-Based Nomogram for Solitary Plasmacytoma of Bone of the Spine: A Real-World Analysis Based on the Surveillance, Epidemiology, and End Results Database.

OBJECTIVE: Solitary plasmacytoma of bone of the spine (SPBS) was rarely detected in the past. However, its incidence has gradually increased with improvements in the diagnosis and understanding of the disease. We aimed to conduct a population-based cohort study to characterize the prevalence and factors associated with SPBS and develop a prognostic nomogram for predicting the overall survival of SPBS patients with a real-world analysis based on the surveillance, epidemiology, and end results database. METHODS: Patients with SPBS at diagnosis were identified using the SEER database from 2000-2018. Multivariable and univariate logistic regression analyses were used to identify factors for developing a novel nomogram. Nomogram performance was evaluated using the calibration curve, area under the curve (AUC), and decision curve analyses. Kaplan-Meier analysis was used to estimate survival durations. RESULTS: A total of 1,147 patients were selected for survival analysis. Multivariate analysis demonstrated that independent predictors for SPBS were as follows: ages: 61-74 and 75-94, marital status: unmarried, treatment: radiation alone and radiation with surgery. The 1-, 3-, and 5-year AUCs for OS were 0.733, 0.735, and 0.735 in the training cohort and 0.754, 0.777, and 0.791 in the validation cohort, respectively. The C-index values in the 2 cohorts were 0.704 and 0.729. The results indicated that nomograms could satisfactorily identify patients with SPBS. CONCLUSIONS: Our model effectively demonstrated the clinicopathological features of SPBS patients. The results indicated that the nomogram had a favorable discriminatory ability, good consistency, and yielded clinical benefits for SPBS patients.

Endobronchial Mass: A Rare Manifestation of Multiple Solitary Plasmacytoma.

Multiple solitary plasmacytoma is the rare presentation of plasma cell neoplasm that can mimic multiple metastases. Primary endobronchial plasmacytoma is an extremely rare condition of extramedullary plasmacytoma. Here, we describe a case of multiple solitary plasmacytoma that initially presented with an endobronchial mass. Teaching Point: The differential diagnosis of multiple lesions in the airway is mainly metastasis and multiple solitary plasmacytoma.

Development of Polyneuropathy, Organomegaly, Endocrinopathy, M Protein, and Skin Changes Syndrome after Conversion from Plasmacytoma of Bone to Multiple Myeloma.

A 36-year-old man developed polyneuropathy, organomegaly, endocrinopathy, M protein, and skin changes (POEMS) syndrome after conversion from solitary plasmacytoma of bone to multiple myeloma. Twenty-four days following the neurological onset, he lost his independent walking ability. The level of serum vascular endothelial growth factor (VEGF) at diagnosis was 5,250 pg/mL. Three months after initiating treatment, he regained his independent walking ability in line with a reduction in the elevated serum VEGF level. Due to their genomic instability gained during conversion, myeloma cells may overproduce humoral factors and cytokines, possibly contributing to the development of neuropathy as well as the production of VEGF.

Solitary plasmacytoma of the rib: A rare tumor to keep in mind: Case report.

Around 5% of plasma cell neoplasias are solitary plasmacytomas, a tumor that is fairly rare. The presence of a localized tumor composed of monoclonal plasma cells that are the same as those found in multiple myeloma and the absence of symptoms that would suggest a disseminated form are used to establish the diagnosis. The thoracolumbar spine is the area most affected. Costal origin is infrequently described. In our case, the patient manifested a right anterosuperior chest wall mass. Imaging showed a mass of tissue with a significant zone of osteolysis of the first rib and no chest wall infiltration. Blood protein immunoelectrophoresis disclosed a monoclonal kappa type IgG. Bence-Jones proteinuria was positive, further suggesting a plasmacytoma of the rib. A percutaneous needle biopsy for pathology study and immunohistochemistry enabled the diagnosis of costal plasmacytoma. Search for other localizations was negative and the diagnosis of solitary plasmacytoma was retained. The patient received radiotherapy and has remained in remission for over a year. The pathology and imaging findings are used to make the diagnosis. Radiotherapy is the therapy of choice, but it presents a risk of progression to other bone lesions, medullary plasmacytosis, and multiple myeloma. There are no known factors that predict systemic recurrence. Surveillance is essential on a regular basis.

Abscopal effect in a patient with solitary extramedullary plasmacytoma of the thyroid: case report.

Background: The abscopal effect is a systemic antitumor response that occurs distant to the irradiation site and is induced by local irradiation. We herein describe a case of solitary extramedullary plasmacytoma (SEP) of the thyroid in which bone metastases disappeared after thyroidectomy and cervical radiotherapy (RT). Case Description: A 68-year-old man with a right cervical swelling for approximately 10 years visited a hospital with left elbow pain that persisted for 5 months. He was referred to our hospital for more detailed examinations and treatment. An immobile mass of approximately 10 cm in diameter was palpable on the right side of the patient's neck. Computed tomography (CT) showed osteolytic changes in the left humerus and right scapula, and a tumor in the right lobe of the thyroid gland. The patient was diagnosed with widely invasive follicular carcinoma and multiple bone metastases and underwent total thyroidectomy. During surgery, tumor infiltration into the trachea was observed. Shaving between the tumor and trachea was performed. Based on the results of a pathological examination, the patient was diagnosed with primary extramedullary plasmacytoma of the thyroid. After surgery, external beam RT was performed on the neck, which also reduced the pain in the left elbow. Positron emission tomography (PET)-CT showed the decreased accumulation of fluorodeoxyglucose (FDG) in the left humerus and right scapula, and the amelioration of osteolytic changes on CT. Conclusions: SEP of the thyroid is rare, and to the best of our knowledge, this is the first case report in which the abscopal effect was observed after thyroidectomy and cervical RT.

Pleural plasmacytomas in a patient with multiple myeloma relapse.

Extramedullary plasmacytoma with pleural involvement in the setting of relapsed multiple myeloma (MM) is a rare yet serious condition, which is associated with an adverse prognosis. This report describes a patient with MM who was in complete remission but relapsed with multiple pleural plasmacytomas. The diagnosis was established in a timely manner and the patient was started on appropriate treatment.

Extramedullary plasmacytoma of the uterine cervix arising in an asymptomatic 46-year-old female.

An extramedullary plasmacytoma is a rare type of plasma cell tumour that can be found in soft tissues throughout the body. The most common location for an extramedullary plasmacytoma is in the head and neck region. Few case reports have previously documented patients with an extramedullary plasmacytoma within the female genital tract. We report a case of a healthy and asymptomatic 46-year-old female who presented to Colposcopy Clinic with a finding of low-grade squamous intraepithelial lesion seen on a routine Pap smear. She was found to have a cervical polyp that was excised. Pathology revealed diffuse sheets of atypical plasma cells with lambda light chain restriction. She was referred to Hematology for extensive work-up as the pathology finding was concerning for a plasma cell neoplasm. Staging investigations, including bone marrow biopsy, skeletal survey, whole body PET-CT scan, serum protein electrophoresis, and serum free light chain testing, were all negative. Surgical resection with a hysterectomy was recommended as the most appropriate course of management. The treatment approach is consistent with guidelines outlined in the literature, whereby extramedullary plasmacytomas, which arise outside of the head and neck region and have clear margins, should undergo surgical resection. Extramedullary plasmacytomas carry a risk of progressing to systemic disease, such as multiple myeloma, making it crucial that these patients be followed with routine surveillance to achieve the most optimal long term survival outcome.

A Case Report on Solitary Extramedullary Plasmacytoma of the Pleura.

Solitary plasmacytoma is an extremely rare form of plasma cell malignancy that presents as a single mass of monoclonal plasma cells located either intraosseous or extramedullary (extraosseous). Extramedullary plasmacytoma can affect any part of the body, but the most common sites of origin are the head and neck region. The involvement of pleura is very rare. Here, we are enlightening this rare presentation and making readers aware of the clinical presentation and management of this rare malignancy.