A Case Series on Unusual Neck Masses

Neck masses can be defined as any abnormal swelling or growth from the level of base of skull to clavicle. They can be benign or malignant so a thorough investigation is necessary to reach to a final diagnosis. Here we report a case series of three unusual neck masses presenting to the Out patient Department of Otorhinolaryngology and Head and Neck Surgery in R. G. Kar Medical College, a tertiary care hospital of Kolkata in a span of 1.5 years. The rarity of the etiology behind the neck masses makes this case series unique.

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.

Incidentally Detected Extramedullary Plasmacytoma of the Gallbladder: A Case Report and Literature Review

Extramedullary plasmacytoma (EMP) can rarely occur in conjunction with multiple myeloma (MM). EMPs are usually detected in the upper aerodigestive tract (UAD) but can also occur along the digestive tract. However, the involvement of gallbladder is uncommon. Gastrointestinal tract symptoms often lead to the diagnosis of EMP in the gallbladder. An 81-year-old man was referred to our hospital with suspected primary gallbladder carcinoma. He was subsequently operated on, and the pathological findings showed EMP of the gallbladder without MM.

Gastrointestinal, Hepatic and Pancreatobiliary Involvement by Plasma Cell Neoplasms: Clinicopathologic Correlations in a Retrospective Cohort of 116 Cases

AIMS

Plasma cell neoplasms (PCNs) may involve the gastrointestinal (GI) tract in two forms: plasmacytoma (PC), an isolated lesion which lacks marrow involvement, and extramedullary myeloma (EMM). However, previous literature on PCNs involving the GI tract, liver and pancreas is limited. We evaluated the clinicopathologic features of the largest series of GI PCNs to date.

METHODS AND RESULTS

Six institutional archives were searched for GI, liver and pancreas cases involved by PCNs. Medical records were reviewed for clinical and imaging features. Histopathologic features evaluated included involved organ, tumor grade and marrow involvement. Overall, 116 cases from 102 patients were identified. Tumors most presented as incidental findings (29%). The liver was most involved (47%), and masses/polyps (29%) or ulcers (21%) were most common findings. Most cases had high-grade morphology (55%). The majority (74%) of GI PCNs were classified as EMM due to the presence of marrow involvement at some point during the disease course, occurring within a year of marrow diagnosis in 46% of patients. PC was classified in 26% of patients due to the lack of marrow involvement. Most (70%) patients died from disease within 10 years (median 14.1) of diagnosis and more than half (58%) died within 6 months.

CONCLUSION

PC and EMM involving the GI tract, liver and pancreas have a wide range of clinicopathologic presentations. Tumors may occur virtually anywhere in the GI tract or abdomen and may precede the diagnosis of marrow involvement. Both GI PC and EMM are associated with a poor prognosis.

Intrathyroidal Plasmacytoma with Pleomorphic Multilobated Bizarre Cells: A Rare Primary Clinicopathological Presentation Mimicking Anaplastic Carcinoma of Thyroid

BACKGROUND

Plasmacytoma involving thyroid gland is infrequent and can present as either primary extramedullary plasmacytoma or secondary to multiple myeloma.

METHODS AND RESULTS

We present a case of 71 years old male who complained of a huge anterior neck swelling accompanied by dysphagia and dyspnoea. Fine needle aspiration cytology was suggestive of anaplastic carcinoma of thyroid (ATC), however, the subsequent histomorphology supported by immunohistochemistry (IHC) astoundingly favoured the diagnosis of plasmacytoma. Further evaluation revealed the presence of lymphadenopathy and single bone lesion in the present case which was rather suggestive of secondary involvement of thyroid to multiple myeloma. However, the case was unique in view of its presentation as a rapidly enlarging thyroid mass associated with stridor and cytomorphological findings which were of an undifferentiated malignancy favouring ATC. The use of a broad and judicious IHC panel clinched the final diagnosis of plasmacytoma.

CONCLUSION

The present case emphasizes the diligent use of IHC in such cases given different therapeutic and prognostic implications.

Parotid gland swelling as an initial presentation of Multiple Myeloma: a case report

INTRODUCTION

Parotid swellings are commonly encountered in ENT Clinics, the cause of which could range from neural conditions, endocrine problems, vitamin deficiencies, and sialadenitis, which may even be a manifestation of an underlying systemic disease. Multiple myeloma represents a clonal proliferation of plasma cells and is a condition in which a parotid swelling might be present, although very uncommon.

CASE PRESENTATION

We report a case of 60-year-old female presented with unilateral parotid swelling, which led to a diagnosis of multiple myeloma based on the investigations.

CONCLUSION

Various imaging modalities are currently available to assess the extent of the swelling and evaluate the soft tissue and osseous involvement. The clinician must have a rigorous insight into the several clinical manifestations and the sites of involvement of the different conditions to make a proper diagnosis.

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

Please present P values consistently.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.

Recurrent extramedullary plasmacytomas without multiple myeloma: A case report with review of the literature

BACKGROUND

Extramedullary plasmacytoma (EMP) is an uncommon presentation and usually occurs in conjunction with multiple myeloma (MM). An EMP without developing MM at any point is an extremely rare presentation, and only seven such cases have been reported in the literature to date.

PRESENTATION OF CASE

We present a case of EMP, who presented with multiple recurrent lesions in rare sites like nasal cavity, testis and skin without the involvement of bone marrow at any point of disease course. He was treated with multiagent chemotherapy (DT-PACE) and continues to be in remission at 29 months post-chemotherapy, which is the longest amongst all the cases reported so far.

DISCUSSION AND CONCLUSIONS

There are no clearly defined guidelines to treat EMP. Our case had a clinical presentation at very unusual sites and was treated with DT-PACE regimen as against the previous seven reported cases and had the most prolonged period of remission.

Primary nodular chest amyloidoma: A case report and review of literature

Primary nodular chest wall amyloidoma, in which a solitary mass of amyloid is deposited in and around the lungs with no evidence of systemic amyloidosis, is extremely rare, most often asymptomatic, and may resemble primary bronchogenic carcinoma. As a result, there are fewer than 100 cases published in the literature and no controlled clinical trials. Primary nodular chest wall amyloidoma is typically diagnosed either as an incidental radiological finding or after very serious and destructive mass growth at which point late-stage respiratory and pain symptoms finally develop, most often in elderly patients. We present imaging studies of a 61-year-old male patient with an unusually massive and destructive chest wall mass, originating in the chest wall, diagnosed as chest wall amyloidoma by histopathology analysis. Our CT, MRI, and PET scan findings are consistent with and contribute to the developing pattern of imaging characteristics seen in other case studies, which can be used to identify amyloidoma before it becomes destructive using non-invasive imaging analyses.

Role of FDG PET in the staging of multiple myeloma

¹⁸F-Fluorodeoxyglucose (FDG) PET has been used for staging of hematologic malignancies for years. In multiple myeloma, this imaging modality can be used in many different scenarios, including initial staging, evaluation of treatment response, and investigation of residual disease or early relapse. FDG PET-CT has excellent diagnostic performance, similar to other advanced imaging modalities such as whole-body CT and MRI, and it is particularly helpful for the assessment of extramedullary disease. It also offers important prognostic information on survival and risk of relapse, both at baseline and after therapy. This review will cover the main applications, advantages, and limitations of FDG PET-CT in multiple myeloma and related clonal plasma cell proliferative disorders, such as smoldering multiple myeloma and plasmacytoma.

Solitary plasmacytoma in the maxillary sinus: 10-year follow-up

Solitary plasmacytoma (SP) is an uncommon form of plasma cell neoplasm occurring intraosseously or in soft tissue and presents as a single mass of monoclonal plasma cells. SP in the maxillary sinus is rare and can be misdiagnosed as other maxillary sinus tumors. The essential examinations in patients with the initial diagnosis of plasmacytoma are bone marrow biopsy, serum and urine electrophoresis, and kappa/lambda ratio (κ:λ ratio) to rule out multiple myeloma (MM). Herein, a rare case of SP in the maxillary sinus treated by surgery and localized radiation is reported. At the 10-year follow-up examination, local recurrence or disseminated development of MM were not evident.

Sellar plasmacytoma with massive bleeding during surgery

Plasmacytoma in the sellar region is an extremely rare occurrence. Sellar plasmacytoma is often difficult to differentiate from pituitary tumors both clinically and radiologically. The occurrence of cranial nerve palsy, the preservation of pituitary hormone function, the presence of sellar floor destruction, and better contrast enhancement are regarded as the differentiating factors between sellar plasmacytoma and pituitary tumors. We recommend adding the massive bleeding properties of sellar plasmacytoma as another characteristic which differentiates it from a pituitary tumor.

Case report: gastric plasmacytoma resistant to radiation therapy

Plasma cell neoplasms are a group of diseases involving the malignant proliferation of plasma cells. One common type of plasma cell neoplasm is multiple myeloma, which typically occurs diffusely in the bone marrow. It can manifest with a variety of presentations, including bone pain, fractures, anemia, infection, hypercalcemia, and renal failure. A less common type of plasma cell neoplasm is the solitary plasmacytoma, which is a local proliferation of plasma cells in the bone or extramedullary tissues. They rarely recur after local radiation therapy.An 83-year-old woman was noted on routine labwork to have elevated total serum protein, and serum immunofixation confirmed IgG/Kappa paraprotein. There was no evidence of end-organ damage characteristic of myeloma: hypercalcemia, renal dysfunction, anemia, or bone lesions. She was diagnosed with monoclonal gammopathy of undetermined significance and placed on observation. Seven years later, she developed mild anemia and an increasing M spike. No abnormalities were found on bone marrow biopsy apart from mildly increased plasma cell proliferation (7-10% of total cells). A PET scan showed increased gastric uptake, concerning for possible gastric malignancy. Upper gastrointestinal endoscopic ultrasound revealed extrinsic compression of the stomach fundus and body due to a 40 mm mass and associated adenopathy. Pathology revealed a kappa-restricted plasma cell neoplasm positive for CD138.The patient underwent radiation therapy localized to the gastric area. Subsequent evaluation revealed a persistent gastric mass. Attempted biopsy resulted in a gastrointestinal bleed, rendering her unable to undergo treatment with lenalidomide and aspirin. She is currently undergoing chemotherapy with bortezomib, cyclophosphamide, and dexamethasone. The case illustrates the potential diversity of plasma cell dyscrasia clinical manifestations. Gastric plasmacytomas are an uncommon type of extramedullary plasmacytoma, particularly rare when resistant to radiation therapy.

Hemorrhage due to attempted excision of a frontal exophytic lesion: A cautionary tale

Background:

Despite mainly benign, exophytic subcutaneous cranial masses present with a myriad of differential diagnosis possibilities, ranging from simple, superficial lesions to complex lesions involving the central nervous system. Although the gold standard imaging modality for the diagnosis of these lesions is magnetic resonance imaging, Doppler Ultrasonography can be a useful, inexpensive, and available tool for evaluation of lesions that could potentially be safely treated in the primary care setting, and lesions that would demand advanced neurosurgical care.

Case Description:

This patient presented with a complex exophytic plasmocytoma that was first diagnosed and erroneously approached as a subcutaneous lipoma with surgical resection in an outpatient surgical setting. This interpretive approach resulted in the failure of the procedure due to significant hemorrhage. The patient was immediately referred to neurosurgical care and transferred to our center. Admission doppler ultrasound imaging revealed absence of the frontal bone, the enriched and profuse vascularization, allowing further and proper diagnostic approach and treatment.

Conclusion:

Ultrasound could be a reliable, fast, and simple imaging method aiding practitioners to perform a better workup for patients with exophytic subcutaneous cranial masses.

Sternal Resection and Reconstruction for Solitary Plasmacytoma of the Sternum: Case Report

A 63-year-old patient was admitted with a sternal fracture and mass. On evaluation, most of the body of the sternum had been destroyed by a tumor. Radical resection of the sternum was performed and part of the major pectoral muscles adherent to the sternal tumor was also resected. The chest wall defect was reconstructed with mesh, bone cement, and a titanium rib plate system. Reconstruction with this method seemed to be an appropriate procedure to prevent instability of the chest wall.

Solitary plasmacytoma of mandible: an unusual bilateral presentation

Plasmacytoma is a neoplastic proliferation of monoclonal plasma cells, which can present clinically as solitary bone neoplasm, extramedullary plasmacytoma, and multiple myeloma. The biological behavior of these tumors is variable from periods of clinical latency to rapid growth and progression from localized forms to more disseminated multiple myeloma. We present the case of solitary plasmacytoma of the mandible with rare bilateral involvement in a 65-year-old female patient. This paper highlights the importance of understanding the maxillofacial manifestations of the disease by the dentist for early diagnosis and thus better prognosis.

Confusion, cognitive impairment, and spinal cord compression caused by plasmacytoma: a case report

Background

Plasmacytomas are rare tumors comprised of neoplastic monoclonal plasma cells and can be found anywhere in the body. Plasmacytomas that involve the nervous system can give rise to diffuse symptoms depending on their location. Patients with confusion or dementia might be difficult to neurologically assess in an acute setting and the subtle symptoms of neurological pathology caused by rare malignancies might go undiagnosed.

Case presentation

The patient is an 80 year old man presenting to the ER with walking difficulties, pain, and confusion. He underwent neurological evaluation for dementia and was eventually diagnosed with possible Alzheimer’s disease and a malignant plasmacytoma causing spinal cord compression. His CSF sample showed normal amyloid rate and very low Aβ. Following rehabilitation and oncological treatment, his walking ability and confusion improved.

Conclusion

This case is unique as we demonstrate that spinal cord compression by plasmacytoma can lead to abnormal CSF levels of several known pathology markers for Alzheimer’s disease and neuronal damage. We suggest that highly divergent amyloid CSF levels could be indicative of spinal pathologies affecting CSF circulation. We also suggest closer assessment of elderly confusion patients in ER settings by consultants specialized in neurological disorders.

Safety and Feasibility Analysis of a Prospective Trial on Stereotactic Body Radiotherapy for Solitary Bone Plasmacytoma

BACKGROUND

There have been reports on the use of hypofractionated stereotactic body radiotherapy (SBRT) for bone plasmacytomas, but no prospective data are available. We present the initial analysis of an ongoing prospective protocol on SBRT addressing the feasibility and safety of this treatment for solitary bone plasmacytomas.

PATIENTS AND METHODS

A prospective cohort of SBRT for solitary bone plasmacytoma was developed. Patients could receive different doses depending on the index bone, from single fraction for skull base lesions, 24 Gy in 3 fractions for spine lesions, and 30 Gy in 5 fractions for other bones. Overall survival, bone events, local control, and progression to multiple myeloma (MM) were measured and compared to our retrospective cohort of patients treated with conformal standard-dose radiotherapy. Quality of life was assessed via the EORTC QLQ-C30 questionnaire, and toxicities were assessed by the CTCAE v5.0 criteria. After 1 year or the inclusion of 5-10 patients, a feasibility and safety analysis was programmed.

RESULTS

Between April 2018 and April 2019, 5 patients were included. All were male, with a median age of 53.1 years. The median follow-up was 21.8 months. No patient had local progression, bone event, or died. Two patients had progressions to MM. The mean survival free of progression to MM was 18.6 months, compared to 19 months in the retrospective cohort; median values were not reached. There were no grade 3 toxicities.

CONCLUSION

SBRT for plasmacytoma is safe and feasible. More robust data are awaited.

Comparison of conventional magnetic resonance imaging and diffusion-weighted imaging in the differentiation of bone plasmacytoma from bone metastasis in the extremities

PURPOSE

To compare conventional magnetic resonance imaging (MRI) and diffusion-weighted imaging (DWI) in the differentiation of bone plasmacytoma from bone metastasis in the extremities.

MATERIALS AND METHODS

A total of 65 patients with 27 bone plasmacytomas (11 men; mean age, 63.6±8.2 [SD] years) and 38 patients with bone metastases (20 men; mean age, 64.1±11.5 [SD] years) were retrospectively included. Plasmacytomas and metastases were compared for size, peritumoral edema, signal intensity (SI), SI pattern, apparent diffusion coefficient (ADC) values and standard deviation (SD) of ADC. Receiver operating characteristic analysis with area under the curve (AUC) was used to calculate sensitivity, specificity, and accuracy of MRI and DWI for the diagnosis of plasmacytoma according to a defined cut-off value.

RESULTS

On conventional MRI, plasmacytomas showed less peritumoral edema (22% vs. 71%; P<0.001), were more often hyperintense on T1-weighted image (48% vs. 18%; P=0.022) and more homogeneous on T2-weighted image (78% vs. 26%; P<0.001) and contrast-enhanced T1-weighted images (70% vs. 25%; P=0.001) than bone metastases. Mean ADC value and SD of ADC were significantly lower in bone plasmacytomas (760.1±196.9 [SD] μm²/s and 161.5±62.7 [SD], respectively) than in bone metastases (1214.2±382.6 [SD] μm²/s and 277.0±110.3 [SD], respectively) (P<0.001). Using an ADC value≤908.3μm²/s, DWI yielded 88% sensitivity and 78% specificity for the diagnosis of plasmacytoma. ADC value yielded best area under the curve (AUC=0.913), followed by SD of ADC (AUC=0.814) and homogeneity on T2-weighted images (AUC=0.757). The combination of conventional MRI and DWI (AUC=0.894) showed improved diagnostic performance over conventional MRI alone (AUC= 0.843) for discriminating between plasmacytoma and metastasis.

CONCLUSION

Conventional MRI in combination with DWI can be useful to discriminate between bone plasmacytoma and bone metastasis in the extremities.

Infiltrating ductal breast carcinoma with monoclonal gammopathy of undetermined significance: A case report

BACKGROUND

Infiltrating ductal breast carcinoma with monoclonal gammopathy of undetermined significance (MGUS) is rare and easily misdiagnosed. Most patients are first diagnosed with MGUS. We report a rare case of MGUS secondary to infiltrating ductal breast carcinoma. We also review the literature to analyze the clinical characteristics and diagnostic methods.

CASE SUMMARY

A 51-year-old woman underwent modified radical mastectomy for infiltrating ductal carcinoma of the right breast and was then treated with radiation and chemotherapy. A decreased platelet count was found on routine blood examination, and MGUS was subsequently diagnosed. This is the first report of the occurrence of MGUS after breast cancer surgery.

CONCLUSION

Vigilance is required to distinguish this rare comorbidity from breast plasmacytoma.

PET/CT F18-FDG with soft tissue plasmacytomas in multiple myeloma

Multiple myeloma is characterized by malignant proliferation of clonal plasma cells. Usually, appears as a generalized disease but it can present as solitary bone plasmacytoma or a solitary soft tissue mass or extramedullary plasmacytoma. In the case of extramedullary involvement, it could present as soft tissue plasmacytomas and the prognosis is poor. The 18F-FDG PET/CT could be a valuable tool for characterization of the medullary and extramedullary involvement. We present a case of F18-FDG PET/CT with extramedullary involvement with soft tissue plasmacytomas in the setting of MM.

Extraosseous multiple myeloma: imaging spectrum in the abdomen and pelvis

Multiple myeloma represents a subset of plasma cell dyscrasias characterized by the proliferation of plasma cells typically in the bone marrow, representing approximately 1% of all cancers and 15% of hematologic malignancies. Often multiple myeloma is limited to the skeletal system; however, a small percentage (<5%) of patients will develop extraosseous manifestations. We review the current WHO classification of plasma cell dyscrasias and use multimodality imaging including US, CT, MRI, and PET-CT to illustrate the spectrum of extraosseous multiple myeloma in the abdomen and pelvis. Because extraosseous multiple myeloma is associated with a poorer prognosis and decreased survival, it is important for the radiologist to become familiar with a variety of extraosseous manifestations in the abdomen and pelvis, especially in a patient with a known diagnosis of multiple myeloma and the development of an abdominal or pelvic mass.

Utilization of radiation therapy in multiple myeloma: trends and changes in practice

Plasma cell disorders including plasmacytomas and multiple myeloma (MM) are exquisitely radiosensitive, and thus, radiation therapy (XRT) is used effectively in their management. The role of XRT in the setting of novel MM therapeutics has not been explored. The 2016 National Cancer Database (NCDB) for MM with patients diagnosed between 2004 and 2013 was studied. Association between utilization of XRT as part of initial therapy and patient, disease, or treating facility characteristics was studied. A total of 111,281 cases with 91.6% MM, 7% osseous plasmacytoma (PLA-O), and 1.4% extramedullary plasmacytoma (PLA-E) were identified. XRT was utilized as part of initial therapy in 25.4% cases, including 69.3% of PLA-O, 60% of PLA-E, and 21.5% of MM patients. Patients with PLA-E and MM were significantly less likely to receive XRT as compared to PLA-O (p < 0.001). A significantly decreased use of XRT was noted over time (p < 0.001), and for advancing patient age (p < 0.001), women (p < 0.001), and blacks (p < 0.001), and with increasing income (p = 0.015). Patients with Medicare were less likely to receive XRT (OR 0.86, 95% CI 0.78, 0.94) as compared to uninsured as were those with initial treatment at academic or high-volume facilities and facilities performing stem cell transplant. There was overall decreased utilization of XRT in recent years, possibly due to advent of efficacious systemic agents for MM therapy, with a higher XRT utilization for plasmacytomas. Patterns of XRT use need to be explored prospectively, so that uniform standards of healthcare delivery can be maintained and treatment heterogeneity can be minimized.

Monoclonal Gammopathies of 'Neurological Significance': Paraproteinemic Neuropathies

OBJECTIVES

To study the clinical profile and outcomes of patients with paraproteinemic neuropathy (PPN) and to explore the utility of nerve conduction studies (NCSs) to differentiate between the demyelinating subtypes.

METHODS

We did a retrospective analysis of patients diagnosed with PPN between January 2010 and December 2019 in an inpatient setting. The study population consisted of patients above 16 years of age presenting with clinical features suggestive of chronic peripheral neuropathy and on evaluation was found to have PPN.

RESULTS

A total of 74 patients were identified. The patients were predominantly in the 6th decade, and the majority were males. The subtypes of PPN were monoclonal gammopathy of undetermined significance (MGUS) (45.9%), POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal plasma cell disorder, and skin changes) (24.3%), solitary plasmacytoma (17.6%), multiple myeloma (8.1%), and AL amyloidosis (4.1%). There are specific features on NCS which can help in identifying POEMS syndrome and IgM MGUS. The majority of patients with PPN tend to stabilize or improve with treatment; however, many have a severe residual disability. New terminology and classification of these entities as 'monoclonal gammopathies of neurological significance' can aid in early diagnosis and the development of effective treatment, to prevent residual disability.

CONCLUSION

PPN has a heterogeneous spectrum of clinical, biochemical, and electrophysiological features. NCS can help distinguish POEMS syndrome and IgM MGUS from other demyelinating subtypes.

Cutaneous Involvement in Plasma Cell Myeloma

OBJECTIVES

Plasma cell myeloma (PCM) involving skin is rare and occurs in 1% to 4% of patients with PCM. We evaluated the clinicopathologic features, cytogenetic findings and clinical follow-up in a series of PCM cases with cutaneous involvement.

METHODS

Cases of PCM with cutaneous involvement were retrospectively reviewed with clinical data.

RESULTS

Skin involvement in PCM occurred in older individuals (mean, 75 years) and was more frequent in men (7/10 patients). All cases showed bone marrow involvement preceding the cutaneous lesions. Histopathologically, the infiltrate was plasmacytic (n = 5) or primitive or plasmablastic (n = 4), and 1 case showed predominantly lymphoplasmacytic features with cyclin D1 immunoreactivity and CCND1 gene rearrangement. Concurrent amyloid deposition was seen in one biopsy, and another case demonstrated coexisting squamous cell carcinoma. The most common immunophenotype was CD138+, CD20-, and CD56+ with light chain restriction. Cytogenetic analysis (available for 7 cases) showed multiple hyperdiploid abnormalities. Follow-up was available for 8 cases (mean, 42 months; range, 11-156 months) and showed short-term disease-related death in 7 of 8 patients.

CONCLUSIONS

Cutaneous involvement in PCM demonstrates a diverse cytomorphologic spectrum with plasmacytic, plasmablastic, or lymphoplasmacytic features and may show concurrent amyloid deposition or neoplasms such as squamous cell carcinoma. Cutaneous involvement typically occurs late in the course of the disease and likely portends poor outcome.