Cutaneous involvement in multiple myeloma: a multi-institutional retrospective study of 53 patients

Recurrent Cutaneous Manifestation in Multiple Myeloma

Cutaneous involvement is an uncommonly encountered manifestation in multiple myeloma (MM), more commonly observed in patients with aggressive subtypes, and often resistant to conventional therapies. Due to its infrequency, reported clinical characteristics have been diverse and relatively non-specific. Particularly uncommon is lower extremity involvement. In this case report, we present a unique case of a patient with refractory immunoglobulin G lambda MM, who subsequently developed recurrence in the lower leg, while being on systemic therapy. Initially, the lesion resembled squamous cell carcinoma, posing a diagnostic challenge. Through meticulous histopathological and immunohistochemical evaluation, cutaneous involvement by MM was confirmed. This case highlights the importance of maintaining a high clinical suspicion for cutaneous involvement in patients with MM who present with new skin lesions, as early diagnosis is crucial for appropriate management.

Utilizing 3D Models to Unravel the Dynamics of Myeloma Plasma Cells' Escape from the Bone Marrow Microenvironment

Recent therapeutic advancements have markedly increased the survival rates of individuals with multiple myeloma (MM), doubling survival compared to pre-2000 estimates. This progress, driven by highly effective novel agents, suggests a growing population of MM survivors exceeding the 10-year mark post-diagnosis. However, contemporary clinical observations indicate potential trends toward more aggressive relapse phenotypes, characterized by extramedullary disease and dominant proliferative clones, despite these highly effective treatments. To build upon these advances, it is crucial to develop models of MM evolution, particularly focusing on understanding the biological mechanisms behind its development outside the bone marrow. This comprehensive understanding is essential to devising innovative treatment strategies. This review emphasizes the role of 3D models, specifically addressing the bone marrow microenvironment and development of extramedullary sites. It explores the current state-of-the-art in MM modelling, highlighting challenges in replicating the disease's complexity. Recognizing the unique demand for accurate models, the discussion underscores the potential impact of these advanced 3D models on understanding and combating this heterogeneous and still incurable disease.

Skin Involvement by Hematological Neoplasms with Blastic Morphology: Lymphoblastic Lymphoma, Blastoid Variant of Mantle Cell Lymphoma and Differential Diagnoses

Hematological neoplasms sharing a blastic morphology may involve the skin. The skin may be either the primary site of occurrence of hematological malignancies with blastic features or cutaneous lesions are the first manifestation of an underlying systemic malignancy. The assessment of skin biopsies of hematological neoplasms with blastic features poses diagnostic problems and requires expert hematopathologists considering a wide range of differential diagnoses. The precise diagnosis of diseases sharing blastic features but with different outcomes and requiring distinct therapies is essential for patient management. The present paper mainly focuses on cutaneous involvement of the blastoid variant of mantle cell lymphoma and lymphoblastic lymphoma of B-cell or T-cell origin. The relevant literature has been reviewed and the clinical aspects, pathological features, prognosis, and therapy of both blastoid mantle cell lymphoma and lymphoblastic lymphoma involving the skin are discussed. A focus on other hematological entities with blastic features, which may involve the skin, to be taken into consideration in differential diagnosis is also given.

Functional Imaging in the Evaluation of Treatment Response in Multiple Myeloma: The Role of PET-CT and MRI

Bone disease is among the defining characteristics of symptomatic Multiple Myeloma (MM). Imaging techniques such as fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET/CT) and magnetic resonance imaging (MRI) can identify plasma cell proliferation and quantify disease activity. This function renders these imaging tools as suitable not only for diagnosis, but also for the assessment of bone disease after treatment of MM patients. The aim of this article is to review FDG PET/CT and MRI and their applications, with a focus on their role in treatment response evaluation. MRI emerges as the technique with the highest sensitivity in lesions' detection and PET/CT as the technique with a major impact on prognosis. Their comparison yields different results concerning the best tool to evaluate treatment response. The inhomogeneity of the data suggests the need to address limitations related to these tools with the employment of new techniques and the potential for a complementary use of both PET/CT and MRI to refine the sensitivity and achieve the standards for minimal residual disease (MRD) evaluation.

Steps towards a Multiple Myeloma Cure?

Multiple myeloma survival has increased in last 20 years because of new treatments, better clinical management due to novel diagnostic tools such as imaging, and better understanding of the disease, biologically and genetically. Novel drugs have been introduced that act with different therapeutic mechanisms, but so have novel therapeutic strategies such as consolidation and maintenance after autologous stem cell transplant. Imaging (such as PET-CT and MRI) has been applied at diagnosis and after therapy for minimal residual disease monitoring. Multiparametric flow and molecular NGS may detect, with high-sensitivity, residual monoclonal plasma cells in the bone marrow. With this novel therapeutic and biological approach, a considerable fraction of multiple myeloma patients can achieve durable remission or even MGUS-like regression, which can ultimately lead to disease disappearance. The big dogma, “Myeloma is an incurable disease”, is hopefully fading.

Central Nervous System Myeloma and Unusual Extramedullary Localizations: Real Life Practical Guidance

Central nervous system localization of multiple myeloma (CNS-MM) accounts for about 1% of all MM during disease course or even rarer at diagnosis. A difference in the origin, i.e., osteodural or primary dural vs leptomeningeal/intraparenchymal, seems to define two distinct types of intracranial myeloma, with different clinical behavior. CNS-MM may occur also as a presentation of MM. Treatment is still unsatisfactory and many treatments have been reported: chemotherapy, intrathecal therapy, and radiotherapy, with dismal prognosis. Other sites of myeloma localization could be also of interest and deserve description. Because of the rarity and aggressiveness of the disease clinicians are often doubtful on how to treat it since there is no general agreement. Moreover, recent drugs such as the anti CD38 monoclonal antibody, immunomodulatory drugs, and proteasome inhibitors have changed the treatment of patients with MM with a significant improvement in overall response and survival. The role of novel agents in CNS MM management and unusual presentations will be discussed as well as the potential role of other new immunomodulatory drugs and proteasome inhibitors that seem to cross the blood-brain barrier. The purpose of this review is to increase awareness of the clinical unusual presentation and neuroradiological findings, give practical diagnostic advice and treatment options algorithm.

Cutaneous Involvement in Diseases with Plasma Cell Differentiation: Diagnostic Approach

Neoplasms with plasma cell differentiation may occasionally involve the skin. Cutaneous lesions may represent the first sign of an underlying systemic plasma cell malignancy, such as multiple myeloma, or the skin itself may be the primary site of occurrence of a hematological tumor with plasma cell differentiation. Starting from examples encountered in our daily practice, we discussed the diagnostic approach pathologists and clinicians should use when faced with cutaneous lesions with plasma cell differentiation. Cases of primary cutaneous marginal zone lymphoma, localized primary amyloidosis/amyloidoma, and cutaneous manifestations (secondary either to multiple myeloma or to plasmablastic lymphoma) are discussed, focusing on the importance of the adequate patient’s work-up and precise clinicopathological correlation to get to the correct diagnosis and appropriate treatment. The pertinent literature has been reviewed, and the clinical presentation, pathological findings, main differential diagnoses, treatment, and outcome of neoplasms with plasma cell differentiation involving the skin are discussed.

Drug resistance and minimal residual disease in multiple myeloma

Great progress has been made in improving survival in multiple myeloma (MM) patients over the last 30 years. New drugs have been introduced and complete responses are frequently seen. However, the majority of MM patients do experience a relapse at a variable time after treatment, and ultimately the disease becomes drug-resistant following therapies. Recently, minimal residual disease (MRD) detection has been introduced in clinical trials utilizing novel therapeutic agents to measure the depth of response. MRD can be considered as a surrogate for both progression-free and overall survival. In this perspective, the persistence of a residual therapy-resistant myeloma plasma cell clone can be associated with inferior survivals. The present review gives an overview of drug resistance in MM, i.e., mutation of β5 subunit of the proteasome; upregulation of pumps of efflux; heat shock protein induction for proteasome inhibitors; downregulation of CRBN expression; deregulation of IRF4 expression; mutation of CRBN, IKZF1, and IKZF3 for immunomodulatory drugs and decreased target expression; complement protein increase; sBCMA increase; and BCMA down expression for monoclonal antibodies. Multicolor flow cytometry, or next-generation flow, and next-generation sequencing are currently the techniques available to measure MRD with sensitivity at 10-5. Sustained MRD negativity is related to prolonged survival, and it is evaluated in all recent clinical trials as a surrogate of drug efficacy.

Cutaneous Multiple Myeloma

Multiple myeloma is a plasma cell dyscrasia characterized by abnormal bone marrow clonal plasma cells, histological confirmation of plasmacytoma, monoclonal protein in serum or urine, and evidence of end-organ damage. Organ involvement in multiple myeloma manifests as CRAB (hyperCalcemia, Renal insufficiency, Anemia, lytic Bone lesions). Cutaneous complications in multiple myeloma have been reported in many different phenotypes such as cryoglobulinemia rash, bruising, amyloid deposition, and squamous cell carcinoma. However, cutaneous metastasis of multiple myeloma is very rare with fewer than 100 cases described in the literature so far. Here, we present a case of biopsy-confirmed primary cutaneous multiple myeloma. Our case has other less common features of multiple myeloma such as renal amyloidosis and a coexisting malignant melanoma. This case report describes a unique presentation of multiple myeloma to understand the disease better.

Extramedullary disease in multiple myeloma

When clonal plasma cells grow at anatomic sites distant from the bone marrow or grows contiguous from osseous lesions that break through the cortical bone, it is referred to as extramedullary multiple myeloma (EMD). EMD remains challenging from a therapeutic and biological perspective. The pathogenetic mechanisms are not completely understood and it is generally associated with high-risk cytogenetics which portends poor outcomes. There is a rising incidence of EMD in the era of novel agents, likely a reflection of longer OS, with no standard treatment approach. Patients benefit from aggressive chemotherapy-based approaches, but the OS and prognosis remains poor. RT has been used for palliative care. There is a need for large prospective trials for development of treatment approaches for treatment of EMD.

Leukaemia cutis for clinicians, a literature review

Leukaemia cutis (LC) describes infiltration of the skin by leukaemia cells, resulting in clinically identifiable cutaneous lesions. LC has a wide range of clinical manifestations, which can make it difficult to distinguish LC from other skin changes. In a group of patients, LC can be the first manifestation of leukaemia, therefore skin biopsy is crucial for the diagnosis. In this mini review, we discuss various types of leukaemia most frequently represented in leukaemia cutis, in both children and adults and skin changes in multiple myeloma, focusing on the clinical presentation of LC and prognosis in patients.

Expert review on soft-tissue plasmacytomas in multiple myeloma: definition, disease assessment and treatment considerations

In this review, two types of soft-tissue involvement in multiple myeloma are defined: (i) extramedullary (EMD) with haematogenous spread involving only soft tissues and (ii) paraskeletal (PS) with tumour masses arising from skeletal lesions. The incidence of EMD and PS plasmacytomas at diagnosis ranges from 1·7% to 4·5% and 7% to 34·4% respectively. EMD disease is often associated with high-risk cytogenetics, resistance to therapy and worse prognosis than in PS involvement. In patients with PS involvement a proteasome inhibitor-based regimen may be the best option followed by autologous stem cell transplantation (ASCT) in transplant eligible patients. In patients with EMD disease who are not eligible for ASCT, a proteasome inhibitor-based regimen such as lenalidomide-bortezomib-dexamethasone (RVD) may be the best option, while for those eligible for high-dose therapy a myeloma/lymphoma-like regimen such as bortezomib, thalidomide and dexamethasone (VTD)-RVD/cisplatin, doxorubicin, cyclophosphamide and etoposide (PACE) followed by SCT should be considered. In both EMD and PS disease at relapse many strategies have been tried, but this remains a high-unmet need population.

Specific cutaneous infiltrates in patients with haematological neoplasms: a retrospective study with 49 patients

BACKGROUND

Haematological neoplasms account for around 9% of all cancers, and they are recognised as an important cause of skin infiltration. However, studies analysing cutaneous metastasis of haematological neoplasms are scarce. We describe the clinical spectrum and outcomes of specific cutaneous manifestations of leukaemias, lymphomas, multiple myeloma (MM), and blastic plasmacytoid dendritic cell neoplasm (BPDN) and make a review of the literature.

METHODS

Data from 49 patients diagnosed with secondary cutaneous infiltration of systemic haematological neoplasms over the last 10 years in a tertiary dermatology centre were retrospectively collected, and clinical-evolutive features were analysed.

RESULTS

Most cases were lymphoma (44.9%, n = 22), followed by leukaemia cutis (38.8%, n = 19), secondary plasmacytoma (10.2%, n = 5) and BPDN (6.1%, n = 3). Nodules were the predominant type of lesion, and most patients presented with multiple (≥3) lesions. In 51% (n = 25) of cases, cutaneous infiltration was detected before the diagnosis of the underlying malignancy. The patients in diverse nosological groups did not differ in terms of survival (P = 0.052).

CONCLUSIONS

We recognise the clinical heterogeneity of specific cutaneous infiltrates. The high proportion of cases in which skin involvement was key to the diagnosis of systemic malignancy emphasises the role of the dermatologist in recognising and correctly managing these patients.

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.

Minimal Residual Disease in Multiple Myeloma: State of the Art and Applications in Clinical Practice

Novel drugs have revolutionized multiple myeloma therapy in the last 20 years, with median survival that has doubled to up to 8–10 years. The introduction of therapeutic strategies, such as consolidation and maintenance after autologous stem cell transplants, has also ameliorated clinical results. The goal of modern therapies is becoming not only complete remission, but also the deepest possible remission. In this context, the evaluation of minimal residual disease by techniques such as next-generation sequencing (NGS) and next-generation flow (NGF) is becoming part of all new clinical trials that test drug efficacy. This review focuses on minimal residual disease approaches in clinical trials, with particular attention to real-world practices.

Metastatic Multiple Myeloma to the Skin

Cutaneous involvement of multiple myeloma (MM) is uncommon, typically occurs in late stage disease, and is a poor prognostic indicator with an approximate eight month median survival. We present a 51-year-old man with relapsed lambda light chain MM who developed abrupt asymptomatic skin metastases. Biopsy revealed a dermis replete of atypical plasma cells, positive for CD138 and CD45. In situ hybridization confirmed lambda light chain restriction. Despite rescue antimyeloma therapy with the anti-CD38 drug daratumumab, he rapidly declined clinically and succumbed to the disease four weeks after presentation. A standard treatment approach for cutaneous MM does not currently exist; however, various techniques to detect cytogenetic abnormalities are emerging and will provide additional prognostic value and direct individualized therapy.

Relapsing Cutaneous Multiple Myeloma Responding to Immunochemotherapy: A Rare Case Report

Multiple myeloma (MM) is characterized by the neoplastic proliferation of plasma cells. The diagnosis of this disease is often suspected through a constellation of clinical signs and symptoms of hypercalcemia, renal failure, anemia, and M-spike proteins. It is the second most common hematological malignancy after non-Hodgkin lymphomas. However, cutaneous MM is an extremely rare entity, and it is associated with poor prognosis. It presents as diffuse erythematous rash or violaceous nodules on the skin. Most common sites of involvement are chest, lower extremities and back. It can be triggered by a local extension of the tumor which is the most common way, surgical procedures and hematogenous spread. An 82-year-old African American male was diagnosed with MM since 2008. He underwent autologous peripheral stem cell transplantation (ASCT) twice in 2010 and 2014; and he had a history of multiple chemotherapy regimens in the past. He had violaceus chest nodules, and the biopsy confirmed the diagnosis of cutaneous MM in 2013. The patient was treated with pomalidomide, panobinostat and dexamethasone with a complete response (CR) to treatment. One year later, the patient developed new skin nodules. Repeat biopsy confirmed the diagnosis of MM again. Patient was treated with daratumumab and had CR to treatment without any new M-spike. Cutaneous lesion is an exceedingly rare presentation of MM. It either present as reddish rash or violaceous nodules involving chest, lower extremities and back. It has a poor prognosis and can be rapidly fatal. Our case is unique because our patient responded to the newer chemotherapy, and lesions resolved despite poor prognosis of this condition.

How We Manage Patients with Plasmacytomas

PURPOSE OF REVIEW

To discuss the diagnostic approach, treatment options, and future considerations in the management of plasmacytomas, either solitary or in the context of overt multiple myeloma (MM).

RECENT FINDINGS

Advanced imaging techniques such as whole-body magnetic resonance imaging and positron emission tomography/computerized tomography are essential for the diagnostic workup of solitary plasmacytomas (SP) to rule out the presence of other disease foci. The role of flow cytometry and clonal plasma cell detection is currently under study together with other prognostic factors for the identification of patients with SP at high risk of progression to overt MM. Solitary plasmacytomas are treated effectively with local radiotherapy whereas systemic therapy is required at relapse. Clonal plasma cells that accumulate at extramedullary sites have distinct biological characteristics. Patients with MM and soft tissue involvement have poor outcomes and should be treated as ultra-high risk. A revised definition of SP that distinguishes between true solitary clonal PC accumulations and SP with minimal bone marrow involvement should be considered to guide an appropriate therapeutic and follow-up approach. Future studies should be conducted to determine optimum treatment approaches for patients with MM and paraskeletal or extramedullary disease.

Multiple myeloma with simultaneous cutaneous and central nervous system involvement

Cutaneous involvement in multiple myeloma is an extremely rare occurrence that is underrecognized and akin CNS involvement, typically occurs late in the disease course, and is associated with an aggressive biology. Pathologic examination is key to the diagnosis and a standard of care treatment has not been established for these patients.