Solitary Plasmacytoma Treated by Lenalidomide-Dexamethasone in Combination with Radiation Therapy: Clinical Outcomes

Solitary plasmacytoma of the pancreas: A rare case report

A plasmacytoma is a cancerous growth of abnormal plasma cells that arise within osseous or soft tissue structures. In soft tissue structures, plasmacytomas can present as solitary or multiple masses in the absence of systemic involvement. Solitary plasmacytomas can be subcategorized as extramedullary plasmacytoma (derived from plasma cells located in soft tissues) or osseous plasmacytoma (derived from plasma cells located in the bone marrow). Infrequently, these tumors can arise as extramedullary lesions from the pancreas and present similarly to other tumors, such as pancreatic neuroendocrine tumors (PNETs). In this article, we report the case of a 62-year-old male with a diagnosis of solitary plasmacytoma of the pancreas. We focus on optimizing diagnosis and management through the application of radiological imaging modalities, specifically computed tomography (CT) scans and positron emission tomography-computed tomography (PET-CT) scans.

Enhanced clinical outcomes with radiotherapy in diagnostically challenging intracranial plasmacytomas: Analysis of 190 cases

BACKGROUND

Intracranial plasmacytomas are rare tumors arising from plasma cells with approximately half of the cases progressing to multiple myeloma (MM). However, there is a lack of comprehensive clinical cohort analysis on the clinical and pathological features, progression, and outcomes of intracranial plasmacytomas.

METHODS

A retrospective analysis of 190 cases was conducted, combining data from 38 cases in a single institution and 152 cases from the literature. Patient demographics, clinical presentations, tumor locations, imaging features, surgical treatments, and follow-up outcomes were collected and analyzed. Survival analysis and Cox regression analysis were performed to identify prognostic factors.

RESULTS

A total of 190 intracranial plasmacytoma patients with an average age of 55.4 years were included in the study. The preoperative misdiagnosis ratio was high at 55.3%, and 59.7% of the tumors affected the calvaria convexity, compared to 40.3% located at the skull base. Resection and biopsy were achieved in 72.4% and 27.6% patients, respectively. Among them, 34.2% (65/190) of patients were initially diagnosed with MM with intracranial plasmacytoma as their first presentation (MM-IPFP), while 63.2% (120/190) of patients were diagnosed with solitary intracranial plasmacytoma (SIP), including 61 extramedullary plasmacytomas and 59 solitary bone plasmacytomas. In the SIP group, 22.4% (24/107) of patients experienced disease progression leading to the development of MM during a median follow-up time of 42.6 months (range 1-230 months). Multivariate analysis unveiled that radiotherapy (HR, 0.05; 95% CI, 0.00-0.87; p = 0.04), not surgery, was a protective prognostic factor for overall survival in MM-IPFP patients. Comparison between the SIP progression group and non-progression group revealed a significant difference of Ki-67 index (non-progression vs. SIP progression, 8.82% ± 7.03 vs. 16.5% ± 10.5, p < 0.05). AUC analysis determined that a cutoff value of 9.0% was the best predictor of SIP progression, with an area under the curve of 0.712.

CONCLUSIONS

This retrospective clinical analysis highlights the potential role of radiotherapy, rather than surgical resection, in improving the outcomes of intracranial plasmacytoma. Additionally, the Ki-67 index is identified as a valuable marker for predicting disease progression. This would provide some evidence for the paradigm of diagnosis and treatment modalities for intracranial plasmacytomas from the large cohort.

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.

Impact of cytogenetic abnormalities on the risk of disease progression in solitary bone plasmacytomas

Most patients with solitary bone plasmacytomas (SBP) progress to multiple myeloma (MM) after definitive radiation therapy as their primary treatment. Whether the presence of high-risk (HR) cytogenetic abnormalities by fluorescence in situ hybridization (FISH) in the clonal plasma cells, obtained either directly from the diagnostic SBP tissue or the corresponding bone marrow examination at the time of diagnosis, is associated with a shorter time to progression (TTP) to MM is unknown. This study evaluated all patients diagnosed with SBP at the Mayo Clinic from January 2012 to July 2022. The presence of del(17p), t(14;16), t(4;14), or +1q (gain or amplification) by FISH in clonal plasma cells was defined as HR. A total of 114 patients were included in this cohort, and baseline FISH was available for 55 patients (48%), of which 22 were classified as HR (40%). The median TTP to MM for patients with SBP and HR FISH was 8 months (95% confidence interval [CI], 6.3-26) compared with 42 months (95% CI, 25-not reached [NR]) in patients with SBP without HR FISH (P < .001). In a multivariate analysis, only HR FISH was a significant predictor for shorter TTP to MM, independent of minimal marrow involvement and an abnormal serum free light chain ratio at diagnosis. Deletion (17p) and gain 1q abnormalities were the most common FISH abnormalities responsible for the short TTP to MM. Thus, assessing for HR FISH abnormalities in clonal plasma cells derived from either the diagnostic SBP tissue or the staging bone marrow examination of patients with newly diagnosed SBP is feasible and prognostic for a shorter TTP to MM.

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.

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.

Radiographic Response of Solitary Plasmacytomas After Conformal Radiotherapy May Be Delayed: Outcomes in the 3D Era

OBJECTIVE

Although recurrence rates after radiotherapy for solitary plasmacytoma (SP) are well established, little is known about how SP responds radiographically, as most historical patients were treated in the 2D era. We evaluated the response to radiotherapy among SP patients staged and treated with 3D techniques, including proton therapy, which has not yet been previously reported.

METHODS AND MATERIALS

Between 2007 and 2021, 15 SP patients (4 extramedullary, 11 bone) staged with 3D imaging and bone marrow evaluation were consecutively treated with definitive radiotherapy. The best response was categorized in 9 evaluable patients according to response evaluation criteria in solid tumors (RECIST) and positron emission tomography response criteria in solid tumors (PERCIST).

RESULTS

With a median follow-up of 34 months, 4 patients relapsed. The median time to the best response was ~2 years (26.6 mo RECIST, 25.4 mo PERCIST). Response rates differed based on response assessment criteria. PERCIST was associated with higher rates of complete (85.7%) or partial response (14.3%) compared with RECIST (16.7% complete, 33.3% partial). Two-year and 4-year PFS for extramedullary SP were 100% and 75%, compared with 91% and 55% for bone ( P =0.75). Patients treated with proton therapy (n=5) did not appear to have different patterns of relapse (1 marginal, 1 distant) compared with those treated with photons or electrons (n=10; 2 distant).

CONCLUSIONS

More conformal dose distribution with proton therapy does not appear to alter patterns of recurrence. Although response rates differ based on criteria by both RECIST and PERCIST assessments, the radiographic response may be slow and requires validation in other cohorts.

A new prediction model for overall survival of elderly patients with solitary bone plasmacytoma: A population-based study

Background

Comprehensive studies on the prognosis of solitary bone plasmacytoma (SPB) are lacking, especially in elderly patients with SPB. This study aims to establish a novel nomogram and risk stratification system to predict the overall survival (OS) of elderly patients with SPB.

Methods

The data of elderly patients with SPB from 2000 to 2017 were identified in the SEER database. SPB patients were randomly assigned to the training set (n = 825) and validation set (n = 354). The Cox regression analysis was used to determine the independent risk factors for OS in elderly SPB patients. The nomogram was established and assessed by the area under the receiver operating curve (AUC), the consistency index (C-index), and the calibration plot. Patients were divided into low-, medium-, and high-risk groups based on the score of the nomogram. The Kaplan-Meier (K-M) curve was used to verify the differences in overall survival among the three groups.

Result

A total of 1,179 elderly patients with SPB were included in the study. Age at diagnosis, prior cancer before SPB, marital status, radiotherapy, and chemotherapy were independent risk factors of OS. The AUC of the 3, 5, and 8-year OS in the training and validation sets were between 0.707 and 0.860. The C-index and calibration plot also indicated that the nomogram has great predictive accuracy and robustness. After risk stratification, patients in the high-risk group had the worst OS.

Conclusion

A novel nomogram was built to predict the OS of elderly patients with SPB. It will help clinicians formulate more reasonable and personalized treatment strategies.

An Unusual Case of Multiple Myeloma with Light-Chain Cast Nephropathy Secondary to a Very Large Plasmacytoma without Bone Marrow Involvement

Here, we report a case of a patient who presented to Strong Memorial Hospital with new-onset renal failure and anemia and was found to have multiple myeloma with lambda light-chain cast nephropathy secondary to a very large (14 cm × 14 cm × 12 cm) plasmacytoma without bone marrow involvement. This case is notable as solitary plasmacytomas are almost never seen with concomitant myeloma-defining CRAB criteria or significantly elevated serum free light-chain ratios. Although solitary plasmacytomas are typically definitively treated with radiation, this case highlights that systemic treatment may be helpful in certain clinical scenarios.

The paradoxical pharmacological mechanisms of lenalidomide and bortezomib in the treatment of multiple myeloma

The combination of bortezomib (Velcade, PS-341) and lenalidomide (Revlimid) for the treatment of multiple myeloma was proved by USA Food and Drug Administration in 2006. Lenalidomide prevents the proliferation of multiple myeloma cells through binding to cereblon and promoting the ubiquitinational degradation of IKZF1 (Ikaros)/IKZF3 (Aiolos). However, the proteasome inhibitor bortezomib would inhibit the ubiquitinational degradation of IKZF1/IKZF3. How bortezomib could not block the antiproliferative effect of lenalidomide on multiple myeloma cells, which is the paradoxical pharmacological mechanisms in multiple myeloma. In this review, we summarized recent advances in molecular mechanisms underlying the combination of bortezomib and lenalidomide for the treatment multiple myeloma, discussed the paradoxical pharmacological mechanisms of lenalidomide and bortezomib in the treatment of multiple myeloma.

Surgery results in low relapse and progression rates in extramedullary plasmacytoma of the head and neck: A case cohort and review of the literature

Extramedullary plasmacytoma of the head and neck is a rare indolent neoplasm. Radiotherapy is often the preferred treatment option with excellent local control and survival. The risk of local recurrence or transformation to multiple myeloma is 10-30%. In our case-cohort, thorough, sensitive initial evaluation for disseminated clonal disease and the incorporation of surgery led to excellent results with no recurrences or systemic progression.

Survival trends and prognostic factors in patients with solitary plasmacytoma of bone: A population-based study

Solitary plasmacytoma of bone (SPB) is a single, isolated plasmacytoma originated from the bone. The survival trends of patients with SPB in recent years remain unknown. And the prognostic system of SPB may also need to be refined. The 18 Surveillance, Epidemiology, and End Results (SEER) databases of the National Cancer Institute in the United States were used to extract data for this study. The third edition of the International Classification of Disease for Oncology (ICD‐O‐3) code 9731 was used to identify cases of SPB. For each case, factors including age at the time of diagnosis, sex, race, marital status, insurance status, primary sites of tumors, and the use of surgery were collected. The outcomes of patients with SPB were compared between two groups. And the prognostic impacts of baseline characteristics and use of surgery was studied. A total of 4103 (from 1976 to 2016) cases of SPB were identified. The median age was 65 years old. Patients in time period‐2 (2008–2016) show better survival as compared to those in time period‐1(1976–2007) (median overall survival: 88 months vs. 73 months, p = 0.0332). Age ≤ 65 years and being male were associated with better outcomes. The widowed individuals had significantly inferior survival and myeloma‐specific survival than the single, married, or divorced individuals (p values all <0.0001). Patients with lesions in bones of skull and face and associated joints had longer survival as compared with those with bone lesions in other sites (median overall survival: 107 months vs. 79 months, p = 0.0694). The use of surgery was significantly associated with improved survival (median survival: surgery performed 98 months vs. not performed 73 months, hazards ratio [HR]: 0.7623, 95% CI: 0.7009–0.8472; p < 0.0001) and myeloma‐specific survival (median myeloma‐specific survival: surgery 160.0 months vs. no surgery 143.0 months, HR: 0.8469, 95% CI: 0.7493–0.9572; p = 0.0078). Multivariable analysis revealed that surgery, marital status, and age were independent prognostic factors for overall survival in patients with SPB. The improvement in the survival of patients with SPB has been observed in recent years. And several potential prognostic factors were identified. Future prospective studies are warranted to explore the roles of novel agents, surgery, and systemic chemotherapy in the treatment of SPB.

Maximizing the Clinical Benefit of Radiotherapy in Solitary Plasmacytoma: An International Multicenter Analysis

Objective: Although local definitive radiotherapy (RT) is considered the standard of care for solitary plasmacytoma (SP), the optimal RT parameters for SP patients have not been defined. The aim of this retrospective study is to analyze the effectiveness of various RT doses, volumes, and techniques, as well as to define the relevant prognostic factors in SP. Methods: Between 2000 and 2019, 84 patients, including 54 with solitary bone plasmacytoma (SBP) and 30 with extramedullary plasmacytoma (EMP), underwent RT at six institutions. Results: The overall RT median dose was 42 Gy (range, 36.0–59.4). The median follow-up period was 46 months. Overall, the local control (LC) rate was 96%, while the complete remission (CR) rate was 46%. The 5-year local relapse-free survival (LRFS), multiple myeloma-free survival (MMFS), progression-free survival (PFS), and overall survival (OS) rates were 89%, 71%, 55%, and 93%, respectively. Using an RT dose above 40 Gy was associated with a higher complete remission (CR) rate and a lower rate of local relapse. Modern irradiation techniques were associated with a trend toward a higher LC rate (98% vs. 87% for conventional, p = 0.09) and a significantly lower local relapse rate (6% vs. 25% for conventional, p = 0.04). However, RT dose escalation and technique did not lead to a significant effect on MMFS, PFS, and OS. Univariate analyses identified several patient characteristics as potentially relevant prognostic factors. In SBP patients, systemic therapy administration was associated significantly with MMFS and PFS rates. Conclusion: Using an RT dose >40 Gy and modern RT techniques may improve the local control and reduce the rate of relapse, without a significant impact on survival rates. The addition of systemic therapies may improve the MMFS and PFS rates of SBP patients.