Low back pain with axillary mass in a perimenopausal woman: A case of schwannomatosis mimicking metastasis.

Schwannomatosis is a rare neurocutaneous syndrome characterized by the presence of multiple schwannomas along the peripheral nerves, distinctly excluding the vestibular nerves. It is recognized as the third principal form of neurofibromatosis, alongside neurofibromatosis types 1 and 2. In this report, we discuss the case of a 45-year-old woman who initially sought medical attention for low back pain and swelling in her left axilla. Her magnetic resonance imaging revealed multiple enhancing intradural extramedullary lesions, along with a mass in the right upper thoracic region and another in the left axilla, raising suspicions of metastasis. However, a comprehensive analysis that aligned imaging results with histopathological findings confirmed the diagnosis of schwannomatosis. This case highlights the importance of differentiating between various conditions that can cause multiple intradural extramedullary masses, such as nerve sheath tumors, meningiomas, and metastasis. The presence of multiple schwannomas suggests a diagnosis of either neurofibromatosis type 2 or schwannomatosis, making the distinction between these two conditions critical for appropriate management.

Spinal extramedullary hematopoiesis mimicking an epidural tumor in a patient with high-risk polycythemia vera: illustrative case.

BACKGROUND: Here the authors present the case of a 43-year-old male with a history of T-cell lymphoma, which was treated with azacitidine plus cyclophosphamide, doxorubicin, vincristine, and prednisone and autologous hematopoietic cell transplant, and high-risk polycythemia vera (PCV) presenting with severe lower-back pain radiating to the bilateral legs with associated lower-extremity weakness and splenomegaly. OBSERVATIONS: T2-weighted magnetic resonance imaging revealed multilevel epidural lesions involving T1-10 and S1-2. Because of severe spinal canal stenosis, the patient underwent surgical decompression of T5-7, with immediate postoperative alleviation of the lower-extremity pain and complete resolution of the lower-leg weakness. Biopsy results revealed extramedullary hematopoiesis (EMH) mimicking a spinal epidural tumor. EMH is radiosensitive and displays a rapid response to low dosages, so the patient was further treated with palliative radiation therapy for residual tumors and symptom alleviation, as well as hydroxyurea and corticosteroids as indicated for cytoreduction. LESSONS: EMH associated with PCV or myeloproliferative conditions occurring within the spine is a rare phenomenon without a standard treatment approach. https://thejns.org/doi/10.3171/CASE23659.

Intradural cystic schwannomas of the spine: A case-based systematic review of an unusual tumor.

Introduction: Cystic schwannomas have only been reported in a few case reports/series. As a result, they may be misdiagnosed and a standardized management approach remains challenging to establish. Research question: The aim of this study was to compile all reported cases of cystic schwannomas and analyze the perioperative course based on a systematic review of the literature with an additional two cases from the authors' experience. Material and methods: We conducted a search of MEDLINE and CENTRAL databases for spinal intradural extramedullary cystic schwannomas, in accordance to the PRISMA statement. All title/abstracts were screened, and a full-text review of the remaining articles was conducted. The results were compiled in tables and summarized using means and standard deviation (SD), median and interquartile range, and percentage and 95% confidence intervals. Results: We identified 263 articles, of which 35, which reported 54 cases, were included. Including our case-reports (n = 56), patients had a mean age of 47.7 years (SD ± 13.0 years) at presentation, 57% were males, and most lesions were lumbar (43%). The most common symptoms were pain (82%) and muscle weakness (68%) with 84% of patients showing neurological findings. 70% of patients showed a complete relief of symptoms after surgery and 96% reported improvement. Only four complications were reported. Discussion and conclusion: Schwannomas should be considered in the differential diagnosis of intradural extramedullary cystic lesions. Patients typically present with subacute to chronic pain and/or neurologic changes. Surgical resection is the primary therapeutic modality and usually has a good to excellent outcome.

Extramedullary and extranodal manifestations in chronic lymphocytic leukemia - an update.

Chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) is a common leukemia characterized by clonal expansion of mature CD5+/CD23 + B cells in the blood, bone marrow (BM) and lymphoid tissues. CLL can undergo extramedullary and extranodal infiltration, with one study noting an incidence of only 0.3 per 100,000 people, and in 17.6% of CLL patients in another report. The most common extranodal sites of leukemic involvement are the skin and central nervous system; however, other organs, including liver, lungs, kidney, gastrointestinal tract, bone, prostate and heart, are occasionally involved. The prognostic significance of extra-medullary CLL is still under debate, but the prognosis in such patients seems to be better in the era of novel targeted drugs. Following a diagnosis of extranodal CLL, survival appears to depend on the site of infiltration. This review presents an overview of CLL in patients with extramedullary and extranodal leukemic lesions, focusing on its epidemiology, pathogenesis, prognosis, clinical characteristics and treatment results.

Targeting erythroid progenitor cells for cancer immunotherapy.

Immunotherapy, especially immune checkpoint blockade therapy, represents a major milestone in the history of cancer therapy. However, the current response rate to immunotherapy among cancer patients must be improved; thus, new strategies for sensitizing patients to immunotherapy are urgently needed. Erythroid progenitor cells (EPCs), a population of immature erythroid cells, exert potent immunosuppressive functions. As a newly recognized immunosuppressive population, EPCs have not yet been effectively targeted. In this review, we summarize the immunoregulatory mechanisms of EPCs, especially for CD45+ EPCs. Moreover, in view of the regulatory effects of EPCs on the tumor microenvironment, we propose the concept of EPC-immunity, present existing strategies for targeting EPCs, and discuss the challenges encountered in both basic research and clinical applications. In particular, the impact of existing cancer treatments on EPCs is discussed, laying the foundation for combination therapies. The aim of this review is to provide new avenues for improving the efficacy of cancer immunotherapy by targeting EPCs.

Characteristics and Outcome of Surgically Treated Patients with Intradural Extra- and Intramedullary Spinal Metastasis-A Single-Center Retrospective Case Series and Review.

OBJECTIVE: Intradural spinal metastases are considered rare. At present, limited information is available on incidence, surgical management, and outcomes. METHODS: We conducted a retrospective patient chart review from 2002 to 2024, identifying all patients surgically treated for intradural spinal metastases. Clinical, surgical and survival data were collected and compared to literature data for patients surgically treated for extradural spinal metastases. RESULTS: A total of 172 patients with spinal metastases were identified with 13 patients meeting inclusion criteria (7.6%). The mean age at diagnosis of intradural spinal metastases was 52 ± 22 years, with diverse primaries including lung (n = 3), breast (n = 2), sarcoma (n = 2), and six unique entities. Intradural spinal metastasis was diagnosed on average of 3.3 years after primary diagnosis. In total, we observed five (38%) intradural-extramedullary and eight (62%) intramedullary metastases, located in the cervical (38.5%), thoracic (46.1%) and lumbar spine (15.4%). The most common preoperative symptoms were pain, sensory changes, and gait ataxia (each 76.9%). Gross total resection was achieved in 54%, and local tumor control in 85%. Postoperatively, 92% exhibited clinical improvement or stability. Most frequent adjuvant treatment was radio- and/or chemotherapy in 85%. The average survival after operation for spinal intradural metastases was 5 months, ranging from 1 month to 120 months. The location of the intradural metastasis in the cervical spine was associated with a significantly more favorable survival outcome (compared to thoracic/lumbar location, p = 0.02). CONCLUSIONS: Intradural location of spinal metastases is rare (7.6%). Even so, surgical resection is safe and effective for neurological improvement, and survival appears lower compared to the reported survival of extradural spinal metastases.

Extramedullary Intracranial Plasmacytomas: A Systematic Review of Literature.

Extramedullary plasmacytoma (EMP) is an uncommon disorder characterized by the development of abnormal plasma cell tumors outside the bone marrow. These tumors are typically observed in various locations, including the upper respiratory tract, gastrointestinal tract, and other soft tissues. Among the less explored manifestations of EMP is intracranial EMP, which remains poorly understood due to the limited literature available on the subject. The objective was to comprehend the population characteristics, localization, type, treatment, and outcomes of intracranial EMP. A systematic review of the literature for EMPs was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. The strategy "extramedullary plasmacytoma AND multiple myeloma" was used for the search. The search terms were queried using PubMed, Embase, Scopus, Cochrane, and Web of Science databases. We included only those studies that presented clinical studies with patients diagnosed with intracranial plasmacytomas. In this study, a total of 84 patients from 25 studies were analyzed. The average age of diagnosis was 57.25 years, with a slightly higher proportion of females (57%) compared to male patients (43%). The most common locations of intracranial plasmacytomas were the clivus (29.7%), frontal lobe (18.9%), parietal lobe (8.1%), occipital lobe (6.7%), temporal lobe (6.7%), and sphenoid (4%). Chordoma and meningioma were the most common differential diagnoses encountered during clinical investigations. Treatment modalities included radiotherapy (RT), chemotherapy (QT), surgical resection (SR), and conservative approaches. The most frequent treatment combinations were SR + RT (19%) and RT only (17.8%). Mortality was reported in 48% of the cases, with complete resolution observed in 10 cases and partial resolution in 3 cases. The average follow-up duration was 37.5 months. The clivus is the most frequently reported site of extramedullary intracranial plasmacytoma (EMIP) occurrence, representing 29.7% of cases. Chordomas were commonly observed alongside EMIPs and emerged as the primary differential diagnosis. RT was the predominant treatment modality, with SR considered when feasible. RT alone demonstrated the highest effectiveness in managing EMIPs (30%), while QT as a sole intervention showed lower efficacy. However, a combination of dexamethasone, lenalidomide, and targeted RT displayed promising results, offering improved tumor response and increased safety.

Diagnostic Accuracy of Somatosensory Evoked Potential and Transcranial Motor Evoked Potential in Detection of Neurological Injury in Intradural Extramedullary Spinal Cord Tumor Surgeries: A Short-Term Follow-Up Prospective Interventional Study Experience from Tertiary Care Center of India.

Objective Intraoperative neuromonitoring (IONM) is an acknowledged tool for real-time neuraxis assessment during surgery. Somatosensory evoked potential (SSEP) and transcranial motor evoked potential (MEP) are commonest deployed modalities of IONM. Role of SSEP and MEP in intradural extramedullary spinal cord tumor (IDEMSCT) surgery is not well established. The aim of this study was to evaluate sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of SSEP and transcranial MEP, in detection of intraoperative neurological injury in IDEMSCT patients as well as their postoperative limb-specific neurological improvement assessment at fixed intervals till 30 days. Materials and Methods Symptomatic patients with IDEMSCTs were selected according to the inclusion criteria of study protocol. On modified McCormick (mMC) scale, their sensory-motor deficit was assessed both preoperatively and postoperatively. Surgery was done under SSEP and MEP (transcranial) monitoring using appropriate anesthetic agents. Gross total/subtotal resection of tumor was achieved as per IONM warning alarms. Sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of SSEP and MEP were calculated considering postoperative neurological changes as "reference standard." Patients were followed up at postoperative day (POD) 0, 1, 7, and 30 for convalescence. Statistical Analysis With appropriate tests of significance, statistical analysis was carried out. Receiver-operating characteristic curve was used to find cutoff point of mMC for SSEP being recordable in patients with higher neurological deficit along with calculation of sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of SSEP and MEP for prediction of intraoperative neurological injury. Results Study included 32 patients. Baseline mean mMC value was 2.59. Under neuromonitoring, gross total resection of IDEMSCT was achieved in 87.5% patients. SSEP was recordable in subset of patients with mMC value less than or equal to 2 with diagnostic accuracy of 100%. MEP was recordable in all patients and it had 96.88% diagnostic accuracy. Statistically significant neurological improvement was noted at POD-7 and POD-30 follow-up. Conclusion SSEP and MEP individually carry high diagnostic accuracy in detection of intraoperative neurological injuries in patients undergoing IDEMSCT surgery. MEP continues to monitor the neuraxis, even in those subsets of patients where SSEP fails to record.

A rare primary sacral glomus tumor presenting as intradural-extramedullary tumor: A Case report and review of literature.

Background: Glomus tumors are very infrequent in the spine where they can grow intraosseously at any level. We were able to identify only eight such cases in the literature, with only one occurring in the sacrum. Here, a 48-year-old male with sacral S1/S2 radiculopathy was found to have a rare glomangioma/glomus tumor of the sacral region. Case Description: A 48-year-old male presented with left-sided S2 radiculopathy characterized by left lower extremity weakness/paresis. The magnetic resonance showed an intradural extramedullary mass measuring 1.8 × 1.9 × 4.3 cm at S1-S2 extending through the left foramen, inhomogeneously enhanced with contrast. He underwent an S1-S2 durotomy with gross total excision of the mass. Pathologically, it proved to be a glomus tumor. Two months postoperatively, he ambulated without the support and demonstrated no tumor recurrence at 1 postoperative year. Conclusion: Glomus tumors involving the sacral region are rare and can be successfully excised resulting in good clinical outcomes.

Mobilization dynamics of bone marrow hematopoietic stem cells during hematopoietic regeneration.

Under stress hematopoiesis, previous studies have suggested the migration of hematopoietic stem cells (HSCs) from bone marrow (BM) to extramedullary sites such as spleen. However, there is little direct evidence of HSC migration from BM to spleen. Here, we induced myeloablation via 5-fluorouracil (5-FU) and showed the direct evidence of HSC migration from BM to spleen during hematopoietic regeneration via a photoconvertible fluorophore. Moreover, during steady-state, HSCs preferentially migrated to BM rather than spleen, but during hematopoietic regeneration HSCs preferred to spleen as a migration site equivalently or greater. Furthermore, in the early phase, HSCs egressed from BM through the attenuated HSC retention. However, HSCs in the late phase gained significantly enhanced cell-autonomous motility, which was independent of chemotaxis. Collectively, HSC mobilization from BM prior to the migration to spleen was dynamically changed from passive to active events during hematopoietic regeneration.

Improved Outcome of Primary Plasma Cell Leukemia in the Current Era with the Use of Novel Agents and Autologous Bone Marrow Transplants-A Single Centre Experience.

Primary Plasma cell leukemia (pPCL) is an aggressive variant of plasma cell dyscrasias. Diagnostic criteria of plasma cell leukemia were recently updated by international myeloma working group to with more than 5% circulating plasma cells or absolute plasma cell count of more than 500/µL. We performed a retrospective analysis of patients diagnosed with pPCL in our department from 2017 to 2022. Clinical characteristics including the symptoms at presentation, organomegaly, bony involvement and extramedullary involvement were collected. Laboratory parameters including the biochemistry serum protein electrophoresis, serum immunofixation, serum free light chain assay, immunoglobulin profile were sent. Treatment and follow up data was collected. Fifteen patients were diagnosed (8 females and 7 males), median age 59 years (34-70). Six were lost to follow up and nine patients who received treatment at our hospital were analyzed for survival outcome. First line treatment was bortezomib- dexamethasone and immunomodulatory drugs (IMiD). Six (66%) achieved partial response or more and 3 had progressive disease. Five of the nine patients (55%) underwent autologous transplantation. Two out of 5 patients (40%) in the transplant group and 3 of the 4 patients (75%) in the non transplant group have died of the progressive disease. Overall survival was 45% at a median follow up of 14 months. Median OS for patients who underwent auto SCT was 16 months (12-22) versus 10 months (8-12) for patients who did not undergo transplant (Student t test; p value 0.018). Three of the patients achieved MRD negativity after transplant and post transplant consolidation therapy. Survival appears to be improved in patients who respond to initial therapy and are able to achieve MRD negativity which should be the goal of treatment in these patients.

Differential regulation by CD47 and thrombospondin-1 of extramedullary erythropoiesis in mouse spleen.

Extramedullary erythropoiesis is not expected in healthy adult mice, but erythropoietic gene expression was elevated in lineage-depleted spleen cells from Cd47-/- mice. Expression of several genes associated with early stages of erythropoiesis was elevated in mice lacking CD47 or its signaling ligand thrombospondin-1, consistent with previous evidence that this signaling pathway inhibits expression of multipotent stem cell transcription factors in spleen. In contrast, cells expressing markers of committed erythroid progenitors were more abundant in Cd47-/- spleens but significantly depleted in Thbs1-/- spleens. Single-cell transcriptome and flow cytometry analyses indicated that loss of CD47 is associated with accumulation and increased proliferation in spleen of Ter119-CD34+ progenitors and Ter119+CD34- committed erythroid progenitors with elevated mRNA expression of Kit, Ermap, and Tfrc. Induction of committed erythroid precursors is consistent with the known function of CD47 to limit the phagocytic removal of aged erythrocytes. Conversely, loss of thrombospondin-1 delays the turnover of aged red blood cells, which may account for the suppression of committed erythroid precursors in Thbs1-/- spleens relative to basal levels in wild-type mice. In addition to defining a role for CD47 to limit extramedullary erythropoiesis, these studies reveal a thrombospondin-1-dependent basal level of extramedullary erythropoiesis in adult mouse spleen.

Angelica sinensis polysaccharides promote extramedullary stress erythropoiesis via ameliorating splenic glycolysis and EPO/STAT5 signaling-regulated macrophages.

Conventional treatments exhibit various side effects on chronic stress anemia. Extramedullary stress erythropoiesis is a compensatory mechanism, which may effectively counteract anemia. Angelica sinensis polysaccharides (ASP) are the main active ingredient found in Angelica sinensis and exhibit antioxidant and hematopoietic effects. However, the effects of ASP on extramedullary stress erythropoiesis remain to be unclear. Here, we demonstrated the protective effects of ASP on chemotherapeutic drug 5-fluorouracil (5-FU)-induced decline in peripheral blood parameters such as RBC counts, HGB, HCT, and MCH, and the decline of BFU-E colony enumeration in the bone marrow. Meanwhile, ASP promoted extramedullary erythropoiesis, increasing cellular proliferation in the splenic red pulp and cyclin D1 protein expression, abrogating phase G0/G1 arrest of c-kit+ cells in mouse spleen. RT-qPCR and immunohistochemistry further revealed that ASP increased macrophage chemokine Ccl2 genetic expression and the number of F4/80+ macrophages in the spleen. The colony-forming assay showed that ASP significantly increased splenic BFU-E. Furthermore, we found that ASP facilitated glycolytic genes including Hk2, Pgk1, Pkm, Pdk1, and Ldha via PI3K/Akt/HIF2α signaling in the spleen. Subsequently, ASP declined pro-proinflammatory factor IL-1ß, whereas upregulating erythroid proliferation-associated genes Gdf15, Bmp4, Wnt2b, and Wnt8a. Moreover, ASP facilitated EPO/STAT5 signaling in splenic macrophages, thus enhancing erythroid lineage Gata2 genetic expression. Our study indicated that ASP may improve glycolysis, promoting the activity of splenic macrophages, subsequently promoting erythroid progenitor cell expansion. Additionally, ASP facilitates erythroid differentiation via macrophage-mediated EpoR/STAT5 signaling; suggesting it might be a promising strategy for stress anemia treatment.

[Multiple myeloma with t (8;14) and t (11;14) and extramedullary infiltration of multiple organs].

A 69-year-old man presented with lumbago and was diagnosed with multiple myeloma (IgD-λ type, R-ISS stage II) with bone-destructive lesions in the lumbar spine and sacrum. Chromosome analysis showed t (8;14)(q24;q32) and t (11;14)(q13;q32). Treatment with daratumumab, lenalidomide, and dexamethasone resulted in partial response, but the disease relapsed, with a copy number increase in t (11;14) and abnormal amplification of the 1q21 region. The patient was treated for CMV enteritis, and was admitted to the hospital due to sudden abdominal pain. Gastrointestinal perforation was diagnosed by CT scan showing free air and wall thickening in the small intestine. Emergency surgery was performed, and the tumors in the perforated area were positive for CCND1 but negative for MYC on immunostaining. The patient's general condition did not improve after the surgery and he died. Pathological autopsy revealed extramedullary infiltration of multiple organs in addition to the small intestine. Extramedullary infiltration is thought to be caused by clonal evolution, and further research is warranted to clarify its pathogenesis and establish effective therapeutic strategies in high-risk patients.

Identifying functional cortical plasticity after spinal tumour resection using navigated transcranial magnetic stimulation.

Our aim was to investigate the effectiveness of navigated transcranial magnetic stimulation (nTMS) brain mapping to characterise preoperative motor impairment caused by an intradural extramedullary (IDEM) tumour and postoperative cortical functional reorganisation. Preoperative and 1-year follow-up clinical, radiological and nTMS data from a case of thoracic spinal meningioma that underwent surgical resection of the lesion were collected and compared. A 67-year-old patient presented with severe progressive thoracic myelopathy (hypertonic paraparesis, clonus, insensate urinary retention) secondary to an IDEM tumour. Initial nTMS assessment showed bilateral upper limb representation with no positive responses for both lower limbs. He underwent successful surgical resection for his IDEM (meningioma WHO grade 1). At 1-year follow-up, the patient's gait was improved and his bladder function normalised. nTMS documented positive responses for both upper and lower limbs and a decrease in the area (right side: 1.01 vs 0.39cm2; left side: 1.92 vs 0.81cm2) and volume (right side: 344.2 vs 42.4uVcm2; left side: 467.1 vs 119uVcm2) of cortical activation for both upper limbs, suggesting a functional reorganisation of the motor areas after tumour resection. nTMS motor mapping and derived metrics can characterise preoperative motor deficit and cortical plasticity during follow-up after IDEM resection.

Interplay of the heart, spleen, and bone marrow in heart failure: the role of splenic extramedullary hematopoiesis.

Improvements in therapies for heart failure with preserved ejection fraction (HFpEF) are crucial for improving patient outcomes and quality of life. Although HFpEF is the predominant heart failure type among older individuals, its prognosis is often poor owing to the lack of effective therapies. The roles of the spleen and bone marrow are often overlooked in the context of HFpEF. Recent studies suggest that the spleen and bone marrow could play key roles in HFpEF, especially in relation to inflammation and immune responses. The bone marrow can increase production of certain immune cells that can migrate to the heart and contribute to disease. The spleen can contribute to immune responses that either protect or exacerbate heart failure. Extramedullary hematopoiesis in the spleen could play a crucial role in HFpEF. Increased metabolic activity in the spleen, immune cell production and mobilization to the heart, and concomitant cytokine production may occur in heart failure. This leads to systemic chronic inflammation, along with an imbalance of immune cells (macrophages) in the heart, resulting in chronic inflammation and progressive fibrosis, potentially leading to decreased cardiac function. The bone marrow and spleen are involved in altered iron metabolism and anemia, which also contribute to HFpEF. This review presents the concept of an interplay between the heart, spleen, and bone marrow in the setting of HFpEF, with a particular focus on extramedullary hematopoiesis in the spleen. The aim of this review is to discern whether the spleen can serve as a new therapeutic target for HFpEF.

Unveiling Multiple Myeloma: Actively Bleeding Extramedullary Gastric Myelomas Lead to Diagnosis.

Multiple myeloma (MM) is a disease of plasma cell replication, leading to a disruption of hematopoiesis, which commonly presents clinically with anemia and fatigue. Extramedullary myelomas are plasma cell collections in bone or soft tissue associated with MM and most often occur later in the disease process. We present a case of a patient with symptomatic anemia with actively bleeding gastric nodules, which were later found to be extramedullary gastric myelomas when pathology demonstrated kappa-restricted plasma cell neoplasms. To confirm the overall diagnosis, a bone marrow biopsy verified the patient had MM.

Diagnostic and Therapeutic Insights into Spinal Glomangioma of a Unique Intradural, Extramedullary Presentation-Systematic Review.

Contemporary literature lacks examples of intradural, extramedullary spinal glomangiomas. Moreover, glomus tumors in general are exceedingly rare among benign spinal tumors and are mostly located within epidural space or within intervertebral foramen, and only a few cases have been documented to date. This report provides a detailed analysis of the clinical presentation, imaging characteristics, surgical intervention, and pathological findings of a 45-year-old patient experiencing progressive locomotor deterioration. The tumor was surgically excised, and subsequent histological examination identified it as a representative of glomus tumors-a glomangioma. Notably, this represents a unique case as it was the first example of such a tumor being discovered intradurally. Radical surgical excision remains the modality of choice in most benign spinal tumors of this localization. Although the malignant transformation of glomus tumors within the spine has not been documented thus far, cases have arisen in other areas. Consequently, we will investigate potential oncological treatments for cases with malignant potential and highlight advancements in surgical techniques for benign intradural spinal tumors.

Case report: An uncommon presentation of extramedullary plasmacytoma without a concurrent diagnosis of multiple myeloma.

Introduction: Extramedullary plasmacytoma (EMP) is an uncommon solitary tumor originating from neoplastic plasma cells located outside the bone marrow. Despite its rarity, the occurrence of EMP without a concurrent diagnosis of multiple myeloma (MM) is considered extremely rare. Approximately 80-90% of EMP cases are found in the head and neck region, with a higher incidence in men aged between 50 and 60 years. The current treatment modalities include radiotherapy (RT) as a first-line approach, with surgery or chemotherapy regarded as other therapeutic options. While RT proves effective in the majority of EMP cases, there are instances where the tumor remains refractory to radiation. In this case report, we present an unusual scenario of EMP resistant to RT without concurrent signs of multiple myeloma which was successfully treated with surgery followed by systemic therapy. Case report: A 72-year-old male was admitted to the Head and Neck Cancer Clinic with a 6-month history of swallowing difficulties. He denied experiencing weight loss or pain on swallowing. Basic laboratory tests yielded results within normal limits, except for beta-2 microglobulin. Physical examination revealed an enlarged submandibular lymph node on the right side. Fiberoptic examination identified a soft tissue polypoid mass within the right piriform fossa, slightly protruding into the vocal slit. A CT scan displayed a well-circumscribed 2 cm polypoid, homogeneously enhancing soft tissue mass adjacent to the posterior surface of the epiglottis and the right side of the tongue base. Bone marrow biopsy revealed no abnormalities, and there were no clinical or laboratory signs of multiple myeloma. Based on the tumor biopsy results and imaging studies, a diagnosis of EMP was made. Due to the lack of response to RT, surgical removal of the tumor was pursued, followed by systemic therapy. Ultimately, the patient achieved full recovery with effective disease control. Conclusion: In conclusion, EMP without concurrent multiple myeloma is an exceedingly rare condition that demands a multidisciplinary approach for both diagnosis and treatment. Moreover, although RT continues to be the primary standard treatment for EMP, in some cases other therapeutic regimens prove to be successful.