Recurrence of solitary plasmacytoma in the liver 10 years after the onset of multiple bone lesions.

A 79-year-old man presented with a history of solitary plasmacytoma in the bone 10 years ago. Chemoradiotherapy was effective, and remission was maintained with intermittent treatment at relapse of the bone lesions. One year after the last treatment, a follow-up computed tomography (CT) scan revealed multiple liver masses, and a liver biopsy revealed plasmacytoma. There was no clonal plasma cell infiltration in the bone marrow, and the final diagnosis was solitary plasmacytomas of the liver. Although liver involvement is known in relapsed refractory multiple myeloma, solitary plasmacytoma in the relapsed stage confined to the liver is rare, and all previous reports have been from the initial presentation. To the best of our knowledge, this is the first recurrent case of solitary plasmacytoma of the liver.

[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.

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.

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.

Novel Nomograms and Web-Based Tools Predicting Overall Survival and Cancer-specific Survival of Solitary Plasmacytoma of the Spine.

STUDY DESIGN: Retrospective analysis. OBJECTIVE: This study aimed to establish nomograms for predicting overall survival (OS) and cancer-specific survival (CSS) in patients with solitary plasmacytoma of the spine (SPS). SUMMARY OF BACKGROUND DATA: SPS is a rare type of malignant spinal tumor. A systematic study of prognostic factors associated with survival can provide guidance to clinicians and patients. Consideration of other causes of death (OCOD) in CSS will improve clinical practicability. METHODS: A total of 1078 patients extracted from the SEER database between 2000 and 2018 were analyzed. Patients were grouped into training and testing data sets (7:3). Factors associated with OS and CSS were identified by Cox regression and competing risk regression, respectively, for the establishment of nomograms on a training data set. The testing data set was used for the external validation of the performance of the nomograms using calibration curves, Brier's scores, C-indexes, time-dependent receiver operating characteristic curves, and decision curve analysis (DCA). RESULTS: Age and grade were identified as factors associated with both OS and CSS, along with marital status, radiation for OS, and chemotherapy for CSS. Heart disease, cerebrovascular disease, and diabetes mellitus were found to be the 3 most common causes of OCOD. The nomograms showed satisfactory agreement on calibration plots for both training and testing data sets. Integrated Brier score, C-index, and overall area under the curve on the testing data set were 0.162/0.717/0.789 and 0.173/0.709/0.756 for OS and CSS, respectively. DCA curves showed a good clinical net benefit. Nomogram-based web tools were developed for clinical application. CONCLUSION: This study provides evidence for risk factors and prognostication of survival in SPS patients. The novel nomograms and web-based tools we developed demonstrated good performance and might serve as accessory tools for clinical decision-making and SPS management. LEVEL OF EVIDENCE: 3.

Extramedullary relapse of Immunoglobulin A-kappa myeloma manifesting as plasmacytoma of the pleura without bone marrow involvement and following autologous bone marrow transplant: a case report.

BACKGROUND: Recurrence of multiple myeloma is among the most challenging issues for patients and treating physicians reported after autologous stem cell transplantation. However, extramedullary involvement after chemotherapy and transplantation has been rarely reported, especially as pleural manifestations. Protein electrophoresis indicated immunoglobulin A monoclonal kappa plasma cell neoplasm in our case. CASE PRESENTATION: A 48-year-old middle-eastern man was referred to our clinic with cough, dyspnea, fever, and left side pleural effusion. A year after chemotherapy and autologous bone marrow transplantation, the patient presented with features in favor of pleural relapse, without bone marrow involvement. Protein electrophoresis demonstrated immunoglobulin A monoclonal kappa plasma cell neoplasm in our case. The patient was effectively treated with dexamethasone, thalidomide, cisplatin, doxorubicin, cyclophosphamide, and etoposide with no notable adverse effects. CONCLUSION: Physicians should be aware of various presentations of multiple myeloma relapse, especially in autologous stem cell transplantation patients. Atypical and unique presentations such as the pleural involvement warrant further reporting of evidence to provide early management and treatment options.

A retrospective study of canine oral extramedullary plasmacytoma over a 15-year period (July 2004-July 2019): Treatment, histologic parameters and clinical outcomes.

A total of 45 cases of canine oral extramedullary plasmacytomas (EMPs) presented to a tertiary referral institution over a 15-year period were examined. Histologic sections of 33 of these cases were examined for histopathologic prognostic indicators. Patients underwent variable treatment including surgical intervention, chemotherapy and/or radiation therapy. Long term survival was observed in the majority of dogs with a median survival time of 973 days (2-4315 days). However, almost 1/3 of dogs had progression of plasma cell disease, including two cases with myeloma-like progression. Histologic characterization of these tumours did not reveal criteria to predict tumour malignancy. However, cases without tumour progression did not exceed 28 mitotic figures in ten 400× fields (2.37 mm2 ). All cases with tumour related death showed at least moderate nuclear atypia. Oral EMPs may represent a local manifestation of systemic plasma cell disease or singular focal neoplasia.

Clinical Presentation and Outcome of Sinonasal Extraosseous Plasmacytoma in Denmark: A Nationwide Cohort From 1980 to 2017.

OBJECTIVES: Extraosseous plasmacytoma (EOP) is a rare plasma cell neoplasm that tends to convert to plasma cell myeloma (PCM) in about 11% to 35% of cases. It has a predilection for the upper respiratory tract, prototypically affecting the nasal cavity and paranasal sinuses. Contemporary first-line treatment is radiotherapy, with more recent studies showing an added benefit of combining radiation with surgery. In this cohort study, we aimed to examine clinical presentation, treatment, and prognosis for all patients nationwide from 1980 through 2017. Furthermore, we determined the size and extension of tumors, investigating the rate at which minimally invasive surgery would have been possible. METHODS: Patients were found in the national pathology registry, and all biopsies were collected for pathology review by a hematopathologist. We performed survival statistics for overall survival (OS), progression-free survival (PFS), and the cumulative incidence of conversion to PCM. RESULTS: Twenty-three patients were included. The median age was 65, and patients were primarily men (78%). Tumors were located in either the nasal cavity (57%), maxillary sinus (39%), or sphenoid sinus (4%). In most cases, the tumor was <5 cm (65%) without extension to adjacent structures (60%). The national incidence was 0.02/100,000 person-years, the median symptom duration until diagnosis was 5 months, and none of the patients presented with contiguous spread to regional lymph nodes. Stand-alone radiotherapy was the predominant treatment (61%). In the entire cohort, one patient died from the initial disease, and six patients died from either relapse of EOP or PCM. The 5-year OS, PFS, and conversion rate to PCM were 78%, 56%, and 23%, respectively. CONCLUSION: SN-EOP responds well to radiotherapy, but relapse and conversion to PCM were not uncommon and entailed a poor prognosis. Most tumors were endoscopically resectable and non-invasive, making the majority of tumors suitable for surgery as an addition to radiation.

[BILATERAL OCULAR PLASMACYTOMA PRESENTING AS ACUTE ANTERIOR UVEITIS].

INTRODUCTION: A 64-year-old woman, presented to the ophthalmology outpatient clinic with abrupt onset of pain, blurred vision and redness in her right eye. Her medical history is remarkable for multiple myeloma, with successful bone marrow transplantation and recurrent disease as secondary plasma cell leukemia, managed with a biologic agent. Examination revealed severe fibrinous anterior uveitis, accompanied by keratic precipitates, rubeosis iridis and raised intra-ocular pressure (IOP) and normal fundus. The patient was treated intensively with topical steroids, IOP lowering agents, systemic acyclovir and prednisone. Response was partial, with further development of posterior synechiae, iris bombe and 360o angle closure. An anterior segment ultrasound demonstrated severely thickened iris. The appearance of bilateral sub-conjunctival salmon patches in both eyes facilitated histopathologic diagnosis by extraocular tissue biopsy which revealed plasma cells infiltration, suggestive of plasmacytoma. Ruthenium plaque radiotherapy administered in a 40Gy dose was initiated in both eyes with a new cycle of systemic chemotherapy. Complete regression after treatment was achieved bilaterally. AIMS: To report a case of bilateral ocular plasmacytoma presenting as an acute anterior uveitis. BACKGROUND: Plasmacytoma, associated with multiple myeloma, is a solid tumor of the lymphoid system composed of monoclonal plasma cells. Ocular involvement is rare and direct infiltration of both eyes is even rarer. METHODS: A case report. CONCLUSIONS: Extramedullary plasmacytoma rarely involves ocular structures. In the setting of systemic malignancy, ocular involvement should be considered, especially when acute inflammation is recalcitrant to therapy.

Clinical features, therapy patterns, outcomes and prognostic factors of solitary plasmacytomas: a report of the Israeli Myeloma Study Group.

Solitary plasmacytoma (SP) is a rare plasma cell dyscrasia. In this retrospective multicenter study, 68 SP patients were included. Compared to solitary extramedullary plasmacytoma (SEP), patients with solitary bone plasmacytoma (SBP) were younger (57.3 vs. 70.9 years, p = 0.031), had larger plasmacytoma (median: 5.4 vs. 3 cm, p = 0.007) and higher median involved free light chain level (61 vs. 25.8 mg/L, p = 0.056). 92.6% of patients were treated by radiotherapy and 11.8% received systemic anti-myeloma treatment. With a median follow-up of 42 months, 45.6% of patients progressed (8.8% - recurrent SP, 36.8% - active myeloma). The median PFS was 58 months and the median OS has not been reached (10-year OS: 84.8%). Patients who received also anti-myeloma treatment had longer PFS compared to those who did not (median not reached vs. 48 months, p = 0.056). In conclusion, SBP and SEP appear to be different diseases. Radiotherapy is the cornerstone in the SP treatment. A large prospective trial is needed to evaluate the impact of adding systemic anti-myeloma treatment to local radiotherapy.

Paraskeletal and extramedullary plasmacytomas in multiple myeloma at diagnosis and at first relapse: 50-years of experience from an academic institution.

From January 1970 to December 2018, 1304 patients were diagnosed with multiple myeloma (MM) at our institution and 256 (19.6%) had plasmacytomas (Ps) (paraskeletal -PPs- 17.6%, extramedullary -EMPs-1.9%). Patients with Ps had lower serum M-protein and less advanced ISS stage than those without. At first relapse, 192 out of 967 patients (19.8%) developed Ps (PPs 14.6%, EMPs 5.1%). The only factor associated with Ps at relapse was the presence of Ps at diagnosis (46% vs 13%, p < 0.00001) with no impact with exposure to novel drugs or previous autologous stem-cell transplantation (ASCT). The median overall survival (OS) was 45, 44 and 20 months for patients without Ps, PPs and EMPs, respectively (p = 0.013). Patients with PPs who underwent ASCT had similar OS than those without Ps (98 vs. 113 months) and significantly longer than those with EMPs (98 vs 47 months, p = 0.006). In patients non-eligible for ASCT the presence of PPs or EMPs was associated with shorter OS compared with patients without Ps (32 vs. 24 vs. 6 months, p = 0.009). In the relapsed setting, a significant survival benefit was observed beyond the year 2000, but still with significant differences among patients without Ps, PPs and EMPs (37 vs 22 vs 16 months, p = 0.003). Importantly, rescue therapy with combinations of proteasome-inhibitors plus immunomodulatory drugs was associated with prolonged OS from first relapse (over 6 years), even in patients with EMPs.

Pediatric Plasma Cell Neoplasms: A Population-Based Study.

INTRODUCTION: Plasma cell neoplasms are exceptionally rare in the pediatric population; the demographic characteristics and the clinical outcomes of plasma cell neoplasms in this population are currently poorly understood. The aim of this study was to provide a comprehensive analysis of pediatric plasma cell neoplasms, based on the United-States Surveillance, Epidemiology, and End Results (SEER) program registries. MATERIALS AND METHODS: All pediatric patients (aged less than 20 years) diagnosed with a malignant plasma cell neoplasm were retrieved from the SEER Program database (18 registries), collecting patient records between 2000 and 2018. The plasma cell neoplasm type, sex, age at diagnosis, year of diagnosis, race and origin, primary disease site, follow-up duration, and vital status at the last known contact were retrieved and analyzed. RESULTS: The age-adjusted incidence rate of plasma cell neoplasms for 1,000,000 person-years was 0.06 for the pediatric population (compared with 90.6 for the adult population). The types of pediatric plasma cell neoplasms predominantly consisted of plasmacytomas, with 11 solitary extraosseous plasmacytoma (42.3%) and 7 solitary bone plasmacytoma (26.9%), while plasma cell myelomas represented only a minority of the neoplasms (8 patients; 30.8%). Most plasmacytomas were localized in the head and neck region. Hispanic patients represented 50% of the pediatric plasma cell neoplasm cases (but only 11.1% of adult cases, P < .01). Female-to-Male ratio was 1.36. Five-year overall survival rates were 88.2% (95% confidence interval [95% CI]: 74.2%-100%) for pediatric plasmacytoma and 36.5% (95% CI: 12.4%-100%) for pediatric plasma cell myeloma (P = .013). CONCLUSION: This first population-based study of pediatric plasma cell neoplasms underlines the rarity of this entity and demonstrates its unique characteristics, including the significant predominance of plasmacytomas, of female patients, and of patients from hispanic origin, and the poor clinical outcomes of pediatric plasma cell myeloma patients.

[A Case of Bladder Plasmacytoma Diagnosed during Treatment of Multiple Myeloma].

A 78-year-old man was treated with Bortezomib, Lenalidomide, and Dexamethasone, for multiple myeloma. Two years after the start of treatment, the patient came to our department with a complaint of gross hematuria. Cystoscopy revealed a tumor on the left wall of the bladder. Urine cytology was negative. Magnetic resonance imaging (MRI) of the lower abdomen showed a slightly high signal on the T2-weighted image, indicating an intravesical mass lesion invading outside the bladder. Contrast-enhanced computed tomography (CT) also showed an intravesical mass and enlarged left external iliac lymph node swelling. Transurethral resection of bladder tumor was performed. The resection specimen showed tumor cells. The pathological examination revealed CD138 (+) and light-chain restriction. The patient was diagnosed with plasmacytoma. The patient was treated with radiation therapy for plasmacytoma of the bladder and surrounding lymph nodes, and then with daratumumab and dexamethasone for multiple myeloma for one year; however, the patient died because of worsening of multiple myeloma.

Extramedullary plasmacytoma with colonic involvement: experience in a tertiary hospital.

A 71-year-old woman diagnosed with type II diabetes mellitus with severe iron deficiency anemia and positive fecal occult blood. Colonoscopy was performed, showing a soft mass in the ascending colon, with biopsies compatible with plasmacytoma and restriction for Kappa light chains. After bone marrow aspiration, associated IgG multiple myeloma was detected, so chemotherapy with VMP (bortezomib, melphalan and prednisone) was started. Colonoscopy six months later showed that the ulcerated lesion had a reduction in tumor size of up to 80%. A 27-year-old male with a history of kidney transplantation and symptoms of chronic diarrhea, colonoscopy was indicated with the finding of a large exophytic and ulcerated lesion in the cecum. Pathology revealed plasmacytoma with restriction of lambda light chains. After ruling out lesions in other locations, the patient was treated with immunochemotherapy according to the Bortezomib-Rituximab-Dexamethasone scheme, with subsequent complete clinical and endoscopic remission. Plasmacytoma accounts for < 4 % of plasma cell tumours. It may appear isolated or associated with another plasma cell neoplasm, mainly multiple myeloma. Its presence in the gastrointestinal tract is rare, being infrequent in the stomach or small intestine, and even rarer in the colonic tract (incidence 1/10,000,000). The clinical manifestations are similar to those of other colon neoplasms, while the treatment or prognosis may differ from those of other neoplasms. In patients with clinical suspicion, it is important to perform an early endoscopic study, especially in patients diagnosed with multiple myeloma.

Relapse with plasmacytoma after upfront autologous stem cell transplantation in multiple myeloma.

Plasmacytoma has been reported to be associated with a poor prognosis in patients with multiple myeloma (MM). In this study, we evaluated the incidence of relapse with plasmacytoma and survival outcomes after upfront autologous stem cell transplantation (ASCT). This study retrospectively analyzed the data of 303 patients with MM who underwent upfront ASCT between April 2000 and April 2018 at eight institutes in the Republic of Korea. In total, 52 patients (17.1%) had plasmacytoma at MM relapse after upfront ASCT, of whom, 27 had paramedullary plasmacytoma (PMD) and 25 had extramedullary plasmacytoma (EMD). Patients with initial plasmacytoma were more likely to have plasmacytoma at MM relapse than those without initial plasmacytoma (37.1% vs. 11.2%). Over a median follow-up of 66.0 months, patients with plasmacytoma at relapse had significantly inferior overall survival (OS) than those without plasmacytoma (43.9 vs. 100.7 months, P < 0.001), but the OS did not significantly differ between patients with EMD and those with PMD (42.2 vs. 56.6 months, P = 0.464). After MM relapse, all patients received salvage therapy, and progression-free survival after relapse was significantly shorter in patients with plasmacytoma than in those without (6.4 vs. 12.4 months, P = 0.007). This study showed that plasmacytoma frequently developed at MM relapse after upfront ASCT in patients with plasmacytoma at the time of diagnosis. Plasmacytoma at relapse was significantly associated with a poor prognosis.

[PRIMARY GASTRIC PLASMACYTOMA IN A BREAST CANCER MALE PATIENT].

INTRODUCTION: Plasmacytoma is a malignant tumor of the plasma cells. Extra-medullary plasmacytoma is rare and with an even lower incidence appears as a primary tumor of the stomach. Initial onset of the disease in the upper gastrointestinal tract is reported in the literature as just second to primary plasmacytomas of the head and neck system. The presenting symptoms are related to the organ involved and systemic symptoms can be weight loss, pain, bleeding and even fever. As this is a rare disease, there is no standard treatment and patients undergo endoscopic resection or chemotherapy with or without additional radiation. The prognosis of the disease depends on the possible future diagnosis of multiple myeloma which can be up to 50% within only a few years. We hereby report a case of a male patient with a past locally advanced breast cancer who was on prolonged adjuvant hormonal treatment. He developed a new symptom of melena and underwent a thorough evaluation including imaging and repeated biopsies from a large gastric lesion. The results were inconclusive mainly because of the differential diagnosis between breast cancer metastases and a new second primary malignancy. In view of a clinical deterioration and lack of diagnosis, an operation of radical gastrectomy was eventually performed only to surprisingly diagnose a rare hematologic disease of the stomach - gastric plasmacytoma. This diagnosis is rare in itself, especially having his previous male breast cancer and maternal multiple myeloma. The diagnostic procedure in this case had also provided the full treatment for his illness.

Solitary Bone Plasmacytoma of Humerus Presenting as a Nonhealing Fracture in a Child: A Rare Entity.

Solitary bone plasmacytoma is an extremely rare entity and is characterized by localized proliferation of monoclonal plasma cells. Plasmacytomas are extremely rare in the pediatric population. The median age at diagnosis is usually the fifth or sixth decade, with axial skeleton being more commonly involved than appendicular. We hereby, report the case of a 13-year-old boy with solitary bone plasmacytoma of the right humerus. Though extremely rare in the pediatric age group, plasmacytomas may be considered as one of the remote differentials in children presenting with solitary bone tumors.