A molecular basis for nonsecretory myeloma

A case report: Nonsecretory multiple myeloma presenting with bone pain

RATIONALE

Nonsecretory multiple myeloma (NSMM) is a rare subtype of multiple myelom, occurring in 1% to 2% of multiple myelom and characterized by the inability of clonal plasma cells to synthesize or secrete immunoglobulins. We describe a 71-year-old male patient who began with bone pain and was referred to hospital several times, but was not properly diagnosed and effectively treated.

PATIENT CONCERNS

A 71-year-old male patient visited our hematology department, complaining of lumbago for 1 year and back pain for half a year.

DIAGNOSES

Low-dose whole-body bone computed tomography: multiple bone destruction of the sternum, ribs, multiple vertebrae and accessories of the spine, pelvis, bilateral humerus, and proximal femur. Monoclonal plasma cells accounted for 17.5% of nuclear cells in bone marrow puncture smear. Fluorescence in situ hybridization detected amplification of CKS1B (1q21) gene. Immunofixation electrophoresis negative. About 10.72% of monoclonal plasma cells were detected by flow cytometry. Finally, he was diagnosed with NSMM.

INTERVENTIONS

The patients received VCD chemotherapy (bortezomib 1.3 mg/m2, d1, d4, d8, d11; cyclophosphamide 300 mg/m2, d1-2, d8-9; dexamethasone sodium phosphate 20 mg, d1-2, d4-5, d8-9, d11-12, once every 21 days).

OUTCOMES

After 2 cycles of VCD treatment, the symptoms of bone pain were significantly relieved, and the efficacy was evaluated as partial response. Follow-up chemotherapy will continue to be completed on schedule. We will continue to follow up to further evaluate the overall survival and progression-free survival.

LESSONS

This case shows that NSMM is easily missed or misdiagnosed.

Soluble B-cell maturation antigen as a monitoring marker for multiple myeloma

Objective: Response to treatment in multiple myeloma (MM) is routinely measured by serum and urine M-protein and free light chain (FLC), as described by the International Myeloma Working Group (IMWG) consensus statement. A non-negligible subgroup of patients however present without measurable biomarkers, others become oligo or non-secretory during recurrent relapses. The aim of our research was to evaluate soluble B-cell maturation antigen (sBCMA) as a monitoring marker measured concurrent with the standard monitoring in MM patients at diagnosis, at relapse and during follow up, in order to establish its potential usefulness in oligo and non-secretory disease. Method: sBCMA levels were measured in 149 patients treated for plasma cell dyscrasia (3 monoclonal gammopathy of unknown significance, 5 smoldering myeloma, 7 plasmacytoma, 8 AL amyloidosis and 126 MM) and 16 control subjects using a commercial ELISA kit. In 43 newly diagnosed patients sBCMA levels were measured at multiple timepoints during treatment, and compared to conventional IMWG response and progression free survival (PFS). Results: sBCMA levels among control subjects were significantly lower than among newly diagnosed or relapsed MM patients [20.8 (14.7-38.7) ng/mL vs. 676 (89.5-1,650) and 264 (20.7-1,603) ng/mL, respectively]. Significant correlations were found between sBCMA and the degree of bone marrow plasma cell infiltration. Out of the 37 newly diagnosed patients who have reached partial response or better per IMWG criteria, 33 (89%) have had at least a 50% drop in sBCMA level by therapy week 4. Cohorts made similarly to IMWG response criteria-achieving a 50% or 90% drop in sBCMA levels compared to level at diagnosis-had statistically significant differences in PFS. Conclusion: Our results confirmed that sBCMA levels are prognostic at important decision points in myeloma, and the percentage of BCMA change is predictive for PFS. This highlights the great potential use of sBCMA in oligo- and non-secretory myeloma.

Oligosecretory myeloma with gastrointestinal tract involvement: an unusual presentation and literature review

A woman in her 70s with vague gastrointestinal (GI) symptoms and unintentional weight loss was referred to endoscopy clinic for investigation and consideration of GI malignancy. CT of the thorax, abdomen and pelvis showed a suspicious mass in the oesophago-gastric junction with a lytic lesion on S1-S2 sacrum. A subsequent upper GI endoscopy revealed two raised, ulcerated tumours on the lesser curvature of the stomach. By the time an MRI of the whole spine was done which revealed multiple metastases involving thoracic, lumbar and sacral skeleton, she had developed leg weakness and paraesthesias, consistent with the imaging findings. A positron emission tomography/CT scan further confirmed the above findings. The initial working diagnosis was primary GI tumour with bony metastases. However, she was later referred to the haematology team after the immunohistochemistry of the tumour showed that it was of a plasma cell origin (CD138 positive) associated with lambda light chain deposits. Serum-free light chain showed a raised lambda light chain of 272 mg/L and kappa light chain of 11.3 mg/L and involved/uninvolved light chain ratio of 24. Bone marrow biopsy confirmed a plasma cell myeloma with moderate disease burden. Monoclonal lambda chains were demonstrated on immunofixation but negative on serum protein electrophoresis and hence a diagnosis of oligosecretory myeloma with GI involvement was made. Subsequent management involved physiotherapy, pain management and chemotherapy, where this woman was commenced on Velcade (generically known as bortezomib), thalidomide and dexamethasone and she continued to experience clinical and biochemical improvement.

Cytogenetic Features and Clinical Outcomes of Patients With Non-secretory Multiple Myeloma in the Era of Novel Agent Induction Therapy

BACKGROUND

Non-secretory multiple myeloma (NSMM) is a rare subtype of multiple myeloma (MM) characterized by the absence of monoclonal protein in the serum and/or urine. We look at the clinical and cytogenetic features of NSMM in this study.

PATIENTS AND METHODS

This study evaluates a cohort of 30 patients with newly diagnosed NSMM seen at the Mayo Clinic, Rochester, MN, between 2008 and 2018 and treated with novel agent induction therapies. Survival outcomes were estimated using the Kaplan-Meier method and compared using the log-rank test.

RESULTS

These patients with NSMM appear to have a large disease burden at diagnosis with a median bone marrow plasma cell percentage of 70% and more than one-half of all patients having Multiple Myeloma International Staging System Stage III disease. There was a higher preponderance for t(11;14) primary cytogenetic abnormality in this NSMM cohort, accounting for more than 50% of the cohort. Finally, the overall survival of this cohort appears to be slightly worse than a matched-control group of newly diagnosed patients with MM with secretory disease.

CONCLUSIONS

Future multi-institution studies confirming these above findings on this rare entity are warranted.

Nonsecretory and Light Chain Escape in Patients With Multiple Myeloma

BACKGROUND

Multiple myeloma (MM) is characterized by the secretion of monoclonal protein by malignant plasma cells in the vast majority of cases. We identified and analyzed patterns of disease relapse and progression associated with disappearance of the paraprotein ("nonsecretory [NS] escape"), or conversion from production of intact Ig molecule to its associated light chain ("LC escape").

PATIENTS AND METHODS

We retrospectively reviewed medical records and a database of 791 consecutive patients with symptomatic MM.

RESULTS

Twenty-eight (3.5%) patients had disease evolution associated with either NS (n = 13) or LC (n = 15) escape. The event occurred at a median of 37 months (range, 3-156 months) after the diagnosis of MM, and after a median of 3 chemotherapy regimens (range, 1-8 regimens). Presence of extramedullary disease at progression was detected in 8 (29%) patients. Sensitivity to chemotherapy before and after escape was present in 21 (75%) and 14 (50%) patients, respectively. After a median follow-up of 55 months, 19 (68%) patients died, and progressive MM was the cause of death in 18 patients. The median overall survival after escape was 20 months (95% confidence interval, 9-25 months), and no significant difference was found between the NS and LC groups (P = .44). The median overall survival after diagnosis of MM was worse in patients with NS/LC escape than in those without escape (52 vs. 94 months; P = .018).

CONCLUSIONS

Our study describes the largest series of NS and LC escape in MM to date. The development of this phenomenon is associated with more aggressive clinical features, frequent resistance to chemotherapy, and worse clinical outcome.

Non-Secretory Myeloma: Ready for a new Definition?

Non-secretory myeloma is a rare myeloma subtype whose diagnosis, until a few years ago, was established by demonstration of monoclonal plasma cells ≥10% in the bone marrow and by negative results on serum and urine electrophoresis and immunofixation studies. However, this type of myeloma could be misdiagnosed if the workup does not include an accurate study of serum free light chain test since some of the patients diagnosed as non-secretory could be light chain only with small amounts monoclonal proteinuria. Due to this limit in classification, all the information available today, generally coming from retrospective studies including patients studied completely and incompletely, could be misleading. A new definition is, thus, needed to distinguish between the true non-secretory, with a possible better prognosis, and the other forms of oligo-secretory myeloma with a prognosis more similar to the secretory form of myeloma. With all the data of the literature, the availability of laboratory and radiological tools, times are mature to depict a new definition of nonsecretory myeloma that deserves a peculiar work up and different response evaluation and, may be, a different therapeutic approach.

Non-secretory multiple myeloma: from biology to clinical management

Multiple myeloma (MM) is the second most common hematologic malignancy in the US. It is typically characterized by production of large amounts of defective immunoglobulin (Ig). Diagnosing MM and monitoring treatment response, including eventual relapse, are largely based on sequential measurements of Ig. However, a small subset of MM called non-secretory multiple myeloma (NSMM) produces no detectable Ig. This subset of true NSMM has become even smaller over time, as the advent of the serum free light chain assay has resulted in the majority of NSMM patients being recategorized as light-chain MM – that is, MM cells that produce only the light-chain component of Ig. True forms of NSMM, meaning MM that secretes no monoclonal proteins whatsoever, constitute a distinct entity that is reviewed; definition of NSMM using current detection methods, discuss the biology underpinning NSMM development, and share recommendations for how NSMM should be managed clinically with respect to detection, treatment, and monitoring.

Multiple qualitative and quantitative methods for free light chain analysis are necessary as first line tests for AL amyloidosis

The objective of this study was to demonstrate the necessity of using different methods for amyloidogenic light chain detection. Serum and urine agarose gel electrophoresis and immunofixation, as well as serum free light chain (FLC) immunoassay measurements, were evaluated in a patient with verified multiple myeloma and consequent AL amyloidosis confirmed by Congo red staining and immunofluorescence techniques. Conventional chemistry tests [serum and urine electrophoresis (SPE and UPE); serum and urine immunofixation (SIFE and UIFE)] were inconclusive. Only quantitative FLC immunoassay (serum free light chain immunoanalysis, SFLC) provided correct diagnostic information. A combination of gel-based SIFE and UIFE with more novel quantitative FLC immunoassays appears necessary when searching for monoclonal immunoglobulin light chain-related diseases.

The emergence of non-secretory multiple myeloma during the non-cytotoxic treatment of essential thrombocythemia: a case report

Introduction

The emergence of multiple myeloma as a second malignancy in patients with essential thrombocythemia is extremely rare. Several cases have been published so far, pointing out the impact of a cytotoxic effect during treatment of essential thrombocythemia on the development of multiple myeloma.

Case presentation

We report the case of a 52-year-old Caucasian man who presented to our hospital because of leukocytosis, a slightly decreased hemoglobin level and thrombocytosis. After a complete hematological work-up, essential thrombocythemia was diagnosed. The patient was included in a multicenter clinical study, treated with anagrelide and his platelet counts were maintained in the normal range for more than 3 years. A sudden drop in his hemoglobin level with normal leukocyte and platelet count occurred at the same time as a back pain. Magnetic resonance imaging of his spine revealed the existence of a pathological fracture of Th4, the collapse of the upper edge of Th7 and osteolytic lesions of multiple thoracic vertebrae. Repeated hematological examinations, including bone biopsy with immunohistochemistry, disclosed diagnosis of multiple myeloma of the non-secretory type.

Conclusions

To the best of our knowledge this is the first published case in which multiple myeloma developed during the treatment of essential thrombocythemia with the non-cytotoxic drug anagrelide. Our attempts to find a common origin for the coexistence of multiple myeloma and essential thrombocythemia have not confirmed the genetic basis of their appearance. Further studies are needed to determine the biological impact of this coexistence.

Non-secretory immunoglobulin E myeloma associated with immunoglobulin G monoclonal gammopathy of undetermined significance

A 68-year old woman came to our hospital with a severe case of anemia. Serum immunoelectropheresis identified a monoclonal immunoglobulin (Ig) G and κ protein. The serum IgE level was within the nomal range and the amounts of remaining immunogloblins were low. On bone marrow aspirate, plasma cells made up 55.5% of nucleated cells and the plasma cells showed positive readings for IgE κ and IgG by immunohistochemistry. Serum immunofixation did not reveal the IgE monoclonal band. She was diagnosed as having non-secretory IgE myeloma with IgG monoclonal gammopathy of undetermined significance. The nature of this rare myeloma will be discussed.

Plasma cell myeloma and related neoplasms

Session 1 of the 2009 Workshop of the Society for Hematopathology/European Association of Haematopathology, Cleveland, OH, focused on plasma cell neoplasms. This report summarizes the salient diagnostic, clinical, and genetic features of plasma cell myeloma (PCM) and related neoplasms. Based on the cases submitted to the workshop, we highlight common diagnostic issues and unusual manifestations of plasma cell neoplasms, such as t(11;14)+ PCM, plasma cell leukemia, and nonsecretory plasmacytoma, as well as plasmablastic transformation of PCM. Additional issues repeatedly raised at the workshop included the differential diagnosis of extramedullary dissemination of PCM vs primary extramedullary plasmacytoma and plasmablastic lymphoma; systemic plasma cell neoplasms in immunocompromised people; and Epstein-Barr virus-associated plasma cell neoplasms. Difficult cases with borderline features presented by submitters emphasized the necessity of integrating clinical, immunophenotypic, and genetic features for appropriate classification of these disorders.

Oligo-secretory myeloma in a patient with ankylosing spondylitis

Non-secretory myeloma is a plasma cell dyscrasia characterized by the absence of serum and urinary monoclonal immunoglobulins on electrophoretic tests. Because of the lack of monoclonal protein, the identification of the disease is more difficult than for secretory myelomas. The coexistence of ankylosing spondylitis and multiple myeloma has been reported occasionally. We report a rare case of oligo-secretory myeloma coexistent with ankylosing spondylitis.

t(11;14) Plasma cell disorder presents as a true nonsecretory, nonproducer multiple myeloma

We describe an extremely rare case of so-called nonsecretory, nonproducer myeloma in an 80-year-old man who presented with weight loss and anemia. The patient's serum protein electrophoresis was negative for M protein spike, and quantitation of his immunoglobulin level was far below the normal range. The bone marrow biopsy showed a sheet-like diffuse plasmacytic infiltrate with essential absence of trilineage hematopoiesis. Flow cytometry analysis and immunohistochemical study demonstrated a strong CD38/CD138/immunoglobulin G heavy chain-positive plasma cell population but failed to detect either cytoplasmic kappa or lambda light chain expression. Chromosomal analysis and dual fluorescence in situ hybridization studies clearly demonstrated the presence of t(11;14)(q13;q32) translocation in the neoplastic plasma cells.

Comparable outcomes in nonsecretory and secretory multiple myeloma after autologous stem cell transplantation

Nonsecretory myeloma (NSM) accounts for <5% of cases of multiple myeloma (MM). The outcome of these patients following autologous stem cell transplantation (ASCT) has not been evaluated in clinical trials. We compared the outcomes after ASCT for patients with NSM reported to the Center for International Blood and Marrow Transplant Research (CIBMTR) between 1989 and 2003, to a matched group of 438 patients (4 controls for each patient) with secretory myeloma (SM). The patients were matched using propensity scores calculated using age, Durie-Salmon stage, sensitivity to pretransplant therapy, time from diagnosis to transplant, and year of transplant. Disease characteristics were similar in both groups at diagnosis and at transplant except higher risk of anemia, hypoalbuminemia, and marrow plasmacytosis (in SM) and plasmacytoma (more in NSM). Cumulative incidence of treatment-related mortality (TRM), relapse, progression-free survival (PFS), and overall survival (OS) were similar between the groups. In multivariate analysis, based on a Cox model stratified on matched pairs and adjusted for covariates not considered in the propensity score, we found no difference in outcome between the NSM and SM groups. In this large cohort of patients undergoing ASCT, we found no difference in outcomes of patients with NSM compared to those with SM.

Immunodiagnostic capabilities of anti-free immunoglobulin light chain monoclonal antibodies

Overproduction of plasma cell-derived monoclonal free kappa or lambda immunoglobulin light chains (FLCs) is a hallmark of multiple myeloma, AL amyloidosis, and light chain deposition disease. Because these components serve as unique cellular and serologic biomarkers, their detection and quantitation has diagnostic, therapeutic, and prognostic import. In this regard, we have developed monoclonal antibodies (mAbs) that specifically recognize the kappa or lambda FLC products of all known human variable and constant region light chain genes. We now report the results of our studies that have demonstrated the capability of these reagents to measure, in a modified fluid-phase capture enzyme-linked immunosorbent assay (ELISA), serum kappa and lambda FLCs at concentrations as low as 5 and 15 ng/mL, respectively. The mAb-based ELISA has greater sensitivity and reproducibility than does the commercially available immunoturbidimetric assay that uses polyclonal anti-FLC antibodies. In addition, the mAbs can immunostain monoclonal FLC-producing plasma cells and pathologic light chain-related amyloid and nonfibrillar tissue deposits. Our anti-FLC mAbs, with their high degree of reactivity and versatility, may provide an invaluable tool in the diagnosis and management of light chain-associated disease.

'Light-chain escape-multiple myeloma'-an escape phenomenon from plateau phase: report of the largest patient series using LC-monitoring

PURPOSE

More intensive and novel therapy options in multiple myeloma (MM) hold the promise to improve treatment outcome. However, disease evolution, induced with long disease duration and extensive pretreatment, has resulted in changes in the biological behaviour of MM and unusual relapse emergence, such as of extramedullary (EM) disease or a shift in secretion from intact immunoglobulin (Ig) to free-light chains (FLCs) only.

METHODS

We studied ten patients since 2004, thoroughly assessed relevant patient characteristics, prominent similarities, SFLC-changes, therapy response, mode and speed of progression, and the incidence of light-chain escape (LCE)-MM within our entire myeloma patient cohort. Serum FLCs (SFLCs) were determined via Freelite-assay (Dade-Behringer Nephelometer).

RESULTS

This report summarizes the to date largest series of ten patients, whose MM appeared stable, as judged by conventional monitoring of intact Ig levels, but developed severe organ dysfunction as a consequence of initially undetected LC-progression. Median number of anti-MM cycles before LCE occurrence was six, including autologous and/or allogeneic stem cell transplants and novel drugs, predominantly thalidomide, in 4/10. Classic diagnostics, such as electrophoresis and quantitative Ig measurement proved futile to detect LC-progression, whereas SFLCs were reliable markers. The LCE-MM prevalence within 407 MM patients treated in our institution between 2004 and 2007 was 2.46%.

CONCLUSIONS

Our report suggests that early detection of LCE-MM by means of serial SFLC measurements may prevent unnecessary complications, allows to detect unusual relapse manifestations in the era of intensive and biological therapy options and possibly also permits to improve treatment results in LCE-MM.

Nonsecretory plasma cell myeloma--becoming even more rare with serum free light-chain assay: a brief review

CONTEXT

Nonsecretory plasma cell myeloma is characterized by an absence of detectable monoclonal protein in both the serum and urine. It is generally reported to comprise approximately 1% to 5% of all cases of plasma cell myeloma and, because of its rarity, requires a high index of suspicion and bone marrow biopsy to establish the diagnosis.

OBJECTIVE

Review the diagnostic strategy when nonsecretory plasma cell myeloma is a clinical consideration in light of a relatively new serum free light chain assay.

DATA SOURCES

Case study and review of the literature.

CONCLUSIONS

Initial data using a recently developed nephelometric serum free light chain assay suggests that only about one fourth of nonsecretory plasma cell myeloma cases may be truly nonsecretory. The definition of nonsecretory plasma cell myeloma should be modified to exclude cases with evidence of clonality using the serum free light chain assay.