Nodular Pulmonary Amyloidosis Is Characterized by Localized Immunoglobulin Deposition and Is Frequently Associated With an Indolent B-cell Lymphoproliferative Disorder

The Lung in Dysregulated States of Humoral Immunity

In common variable immunodeficiency, lung manifestations are related to different mechanisms: recurrent pneumonias due to encapsulated bacteria responsible for diffuse bronchiectasis, diffuse infiltrative pneumonia with various patterns, and lymphomas, mostly B cell extranodal non-Hodgkin type. The diagnosis relies on significant serum Ig deficiency and the exclusion of any primary or secondary cause. Histopathology may be needed. Immunoglobulin (IgG) replacement is crucial to prevent infections and bronchiectasis. IgG4-related respiratory disease, often associated with extrapulmonary localizations, presents with solitary nodules or masses, diffuse interstitial lung diseases, bronchiolitis, lymphadenopathy, and pleural or pericardial involvement. Diagnosis relies on international criteria including serum IgG4 dosage and significantly increased IgG4/IgG plasma cells ratio in pathologically suggestive biopsy. Respiratory amyloidosis presents with tracheobronchial, nodular, and cystic or diffuse interstitial lung infiltration. Usually of AL (amyloid light chain) subtype, it may be localized or systemic, primary or secondary to a lymphoproliferative process. Very rare other diseases due to nonamyloid IgG deposits are described. Among the various lung manifestations of dysregulated states of humoral immunity, this article covers only those associated with the common variable immunodeficiency, IgG4-related disease, amyloidosis, and pulmonary light-chain deposition disease. Autoimmune connective-vascular tissue diseases or lymphoproliferative disorders are addressed in other chapters of this issue.

AL Amyloidoma of the Skin/Subcutis: Cutaneous Amyloidosis, Plasma Cell Dyscrasia or a Manifestation of Primary Cutaneous Marginal Zone Lymphoma?

It is unclear whether AL amyloidoma of the skin/subcutis represents a distinct entity, an indolent precursor of systemic amyloidosis, or a manifestation of cutaneous marginal zone lymphoma (cMZL). We collected 10 cases of cutaneous AL amyloidoma in order to better characterize the clinicopathologic features of this elusive entity (M:F=4:6; median age: 62.5 y, range: 31 to 82 y). Nine patients had a solitary nodule or plaque on the lower extremity (n=7), upper extremity (n=1), or chin (n=1). One patient had an AL amyloidoma on the right thigh and a second lesion on the right arm showing histopathologic features of cMZL without amyloid deposits. Clinical investigations excluded relevant systemic disease in all cases. Microscopically, dermal/subcutaneous deposits of amyloid were associated with sparse to moderate perivascular infiltrates of lymphocytes and monotypic plasma cells (7 with kappa and 3 with lambda light chain restriction). The plasma cells expressed CD56 in one of 9 studied cases. One case was characterized by a t(14;18)(q32;q21)/IGH-MALT1 translocation. Follow-up was available in 8 cases. All remain systemically well after a median time of 86.5 months (range: 40 to 144 mo). Local recurrence of disease was observed in 3 patients. A fourth patient presented with a cMZL without amyloid deposits 8 years after excision of the cutaneous AL amyloidoma. Although our series is small, careful categorization and follow-up of the cases, together with updated information in the literature, show clinical and biological links between AL amyloidomas of the skin/subcutis and cMZL, suggesting that at least a subset of cutaneous AL amyloidoma may represent an unusual manifestation of cMZL (cutaneous mucosa-associated lymphoid tissue lymphomas).

The lung in amyloidosis

Amyloidosis is a disorder caused by misfolding of autologous protein and its extracellular deposition as fibrils, resulting in vital organ dysfunction and eventually death. Pulmonary amyloidosis may be localised or part of systemic amyloidosis.

Pulmonary interstitial amyloidosis is symptomatic only if the amyloid deposits severely affect gas exchange alveolar structure, thus resulting in serious respiratory impairment. Localised parenchymal involvement may be present as nodular amyloidosis or as amyloid deposits associated with localised lymphomas. Finally, tracheobronchial amyloidosis, which is usually not associated with evident clonal proliferation, may result in airway stenosis.

Because the treatment options for amyloidosis are dependent on the fibril protein type, the workup of all new cases should include accurate determination of the amyloid protein. Most cases are asymptomatic and need only a careful follow-up. Diffuse alveolar-septal amyloidosis is treated according to the underlying systemic amyloidosis. Nodular pulmonary amyloidosis is usually localised, conservative excision is usually curative and the long-term prognosis is excellent. Tracheobronchial amyloidosis is usually treated with bronchoscopic interventions or external beam radiation therapy.

Nodular pulmonary amyloidosis with primary pulmonary MALT lymphoma masquerading as metastatic lung disease

Nodular pulmonary amyloidosis is a very rare form of localized amyloidosis involving the lung, with very little known about its nature. It is usually associated with indolent B cell lymphoproliferative disorder and also connective tissue disorders. No definite treatment guideline exists. Many patients respond to chemotherapy with low risk of progression and a 'wait and watch' strategy is also considered a valid treatment option. In this report the authors present a case of nodular pulmonary amyloidosis with pulmonary mucosa associated lymphoid tissue (MALT) lymphoma that presented with features of metastatic malignant disease and after definitive diagnosis decided not to undergo treatment.

Cerebral amyloidoma is characterized by B-cell clonality and a stable clinical course

Amyloidomas are rare amyloid-containing lesions, which may also occur in the central nervous system. Etiology, pathogenesis and clinical course are poorly understood. To gain more insight into the biology of cerebral amyloidoma, they aimed to characterize its histopathological, molecular and clinical features in a retrospective series of seven patients. FFPE tissue specimens were examined using immunohistochemistry, chromogenic in situ hybridization (CISH) for light chains kappa and lambda as well as an IgH gene clonality analysis. Follow-up information was gathered by reviewing patient records and imaging results. Median age of the three males and four females was 50 years (range: 35-53 years). All cerebral amyloidomas were located supratentorially and were classified as lambda light chain amyloidosis (AL-λ; n = 6) and kappa light chain amyloidosis (AL-κ; n = 1) on immunohistochemistry and CISH. B-cell clonality was confirmed by IgH gene clonality assay in all cases examined. After a median follow-up of 21 months, all patients were alive and showed stable disease. No progression to systemic disease was observed. In conclusion, their data suggest that cerebral amyloidoma is a local disease characterized by B-cell clonality and associated with a stable clinical course.

Amyloidosis of the Lung

CONTEXT

-Amyloidosis is a heterogeneous group of diseases characterized by the deposition of congophilic amyloid fibrils in the extracellular matrix of tissues and organs. To date, 31 fibril proteins have been identified in humans, and it is now recommended that amyloidoses be named after these fibril proteins. Based on this classification scheme, the most common forms of amyloidosis include systemic AL (formerly primary), systemic AA (formerly secondary), systemic wild-type ATTR (formerly age-related or senile systemic), and systemic hereditary ATTR amyloidosis (formerly familial amyloid polyneuropathy). Three different clinicopathologic forms of amyloidosis can be seen in the lungs: diffuse alveolar-septal amyloidosis, nodular pulmonary amyloidosis, and tracheobronchial amyloidosis.

OBJECTIVE

-To clarify the relationship between the fibril protein-based amyloidosis classification system and the clinicopathologic forms of pulmonary amyloidosis and to provide a useful guide for diagnosing these entities for the practicing pathologist.

DATA SOURCES

-This is a narrative review based on PubMed searches and the authors' own experiences.

CONCLUSIONS

-Diffuse alveolar-septal amyloidosis is usually caused by systemic AL amyloidosis, whereas nodular pulmonary amyloidosis and tracheobronchial amyloidosis usually represent localized AL amyloidosis. However, these generalized scenarios cannot always be applied to individual cases. Because the treatment options for amyloidosis are dependent on the fibril protein-based classifications and whether the process is systemic or localized, the workup of new clinically relevant cases should include amyloid subtyping (preferably with mass spectrometry-based proteomic analysis) and further clinical investigation.

Amyloidosis: Insights from Proteomics

Amyloidoses are a spectrum of disorders caused by abnormal folding and extracellular deposition of proteins. The deposits lead to tissue damage and organ dysfunction, particularly in the heart, kidneys, and nerves. There are at least 30 different proteins that can cause amyloidosis. The clinical management depends entirely on the type of protein deposited, and thus on the underlying pathogenesis, and often requires high-risk therapeutic intervention. Application of mass spectrometry-based proteomic technologies for analysis of amyloid plaques has transformed the way amyloidosis is diagnosed and classified. Proteomic assays have been extensively used for clinical management of patients with amyloidosis, providing unprecedented diagnostic and biological information. They have shed light on the pathogenesis of different amyloid types and have led to identification of numerous new amyloid types, including ALECT2 amyloidosis, which is now recognized as one of the most common causes of systemic amyloidosis in North America.

Clarifying immunoglobulin gene usage in systemic and localized immunoglobulin light-chain amyloidosis by mass spectrometry

The goal of this study was to investigate the frequency of use of light-chain variable region (IGVL) genes among patients with systemic (AL_S) and localized (AL_L) amyloidosis and to assess for associations between IGVL gene usage and organ tropism. We evaluated clinic charts from 821 AL patients seen at the Mayo Clinic who had bone marrow, fat pad, and solid organ tissue samples typed by liquid chromatography tandem mass spectrometry (LC-MS). We identified 701 patients with AL_S and 120 with AL_L Overall, we were able to identify an IGVL gene in 87 (72%) patients with AL_L and 573 (82%) patients with AL_S When compared with AL_L, LV6-57 was more common, whereas KV3-20 and heavy-chain codeposition were less common in AL_S In this large series of AL_S, characteristics particular to specific genotypes became apparent. LV6-57 patients were more likely to have renal involvement and to harbor a translocation 11;14. LV3-01 patients were less likely to have advanced cardiac disease and renal involvement. LV2-14 patients were more likely to have peripheral nerve involvement, an intact circulating immunoglobulin, and lower circulating dFLC. LV1-44 patients were more likely to have cardiac involvement. KV1-33 patients had more liver involvement and higher circulating dFLC. Finally, KV1-05 was associated with inferior overall survival but not independently of cardiac stage. IGVL gene usage appears to provide clues about disease pathophysiology and tissue tropism. LC-MS is a high-throughput and low-resource technique that can be used to identify IGVL gene from clinical tissue specimens.

[Pulmonary MALT lymphoma and paraneoplastic syndromes]

INTRODUCTION

Primary pulmonary lymphoma is a rare disease; diagnosis is often delayed because of atypical clinical presentation and slow progression.

OBSERVATION

A 42-year-old woman consulted because of haemoptysis. Chest CT-scan showed multiple nodular calcified masses. A lung biopsy led to the diagnosis of pulmonary amyloidosis with pulmonary MALT lymphoma (mucosa-associated lymphoid tissue). The patient developed two paraneoplastic syndromes: a hypertrophic osteoarthropathy and mucinosis.

CONCLUSION

Multiple nodular amyloidosis can be a mode of presentation for pulmonary lymphoma. Paraneoplastic syndromes must be systematically considered and can help in early diagnosis of the disease and its relapse.

Sinonasal Globular Amyloidosis Simulating Malignancy: A Rare Presentation

Primary localized amyloidosis in the head and neck region is a rare entity. The most commonly involved organ is larynx. Primary amyloidosis localized to the sinonasal tract is extremely rare. We report one such case along with a brief review of the associated literature. The aim of reporting this case is to emphasize the fact that sometimes nasal amyloidosis can also present with signs and symptoms of nasal and nasopharyngeal malignancy. The definitive diagnosis in such cases depends upon histopathology and further confirmed by immunohistochemistry. A 55-year old male presented with recurrent episodes of nasal bleed, bilateral nasal obstruction, and bilateral hearing loss from last 7 years. On clinical examination a mass was found in the nasal cavity on both sides reaching up to the nasopharynx. Contrast enhanced CT scan revealed that the mass was extending up to the skull base and destroying bony landmarks of the nasal cavity and paranasal sinuses. Mass was proved to be amyloidosis after histopathological examination. It showed multiple blotches of globular submucosal deposit of amyloid, on staining with Congo red. Immunohistochemistry confirmed AL amyloidosis with expression of mixed kappa and lambda light chain immunoglobulin (κ > λ). No evidence of systemic amyloidosis was found after proper work up. It was managed by conservative surgery.

Immunoglobulin Light Chain Systemic Amyloidosis

Immunoglobulin light chain amyloidosis (AL) is a rare, complex disease caused by misfolded free light chains produced by a usually small, indolent plasma cell clone. Effective treatments exist that can alter the natural history, provided that they are started before irreversible organ damage has occurred. The cornerstones of the management of AL amyloidosis are early diagnosis, accurate typing, appropriate risk-adapted therapy, tight follow-up, and effective supportive treatment. The suppression of the amyloidogenic light chains using the cardiac biomarkers as guide to choose chemotherapy is still the mainstay of therapy. There are exciting possibilities ahead, including the study of oral proteasome inhibitors, antibodies directed at plasma cell clone, and finally antibodies attacking the amyloid deposits are entering the clinic, offering unprecedented opportunities for radically improving the care of this disease.

Nodular pulmonary light chain deposition disease: an entity associated with Sjögren syndrome or marginal zone lymphoma

Background

Light chain deposition disease (LCDD) is usually a systemic disorder characterised by non-amyloid monoclonal immunoglobulin light chain deposition in tissues. Localised nodular pulmonary (NP) LCDD is a rare and poorly characterised entity and, owing to the difficulties in diagnosis, limited data are available.

Methods

We investigated the clinical, radiological and pathological characteristics of a series of six confidently diagnosed cases of NPLCDD.

Results

There were three men and three women with ages ranging from 33 to 74 years. In all cases there were single or multiple pulmonary nodules, in one case associated with cysts. Two patients had no previous history of a lymphoproliferative or autoimmune disorder, two had Sjögren syndrome (SS) and two had extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma). Lung biopsies led to diagnoses of MALT lymphoma in four patients, including both of those with a previous history of lymphoma and one with SS. In five cases the diagnosis was confirmed by liquid chromatography–tandem mass spectrometry (LC–MS/MS) and in one by electron microscopy. There was no evidence of systemic LCDD in any of the cases. Five patients had an indolent course in spite of limited therapeutic intervention while, in the patient who died, the cause of death was related to the spread of the lymphoma and was not due to the pulmonary lesions.

Conclusions

NPLCDD is an indolent disease, in most cases associated with MALT lymphoma or autoimmune disease.

The many faces of small B cell lymphomas with plasmacytic differentiation and the contribution of MYD88 testing

Plasmacytic differentiation may occur in almost all small B cell lymphomas (SBLs), although it varies from being uniformly present (as in lymphoplasmacytic lymphoma (LPL)) to very uncommon (as in mantle cell lymphomas (MCLs)). The discovery of MYD88 L265P mutations in the vast majority of LPLs has had a major impact on the study of these lymphomas. Review of the cases contributed to the 2014 European Association for Haematopathology/Society for Hematopathology slide workshop illustrated how mutational testing has helped refine the diagnostic criteria for LPL, emphasizing the importance of identifying a clonal monotonous lymphoplasmacytic population and highlighting how LPL can still be diagnosed with extensive nodal architectural effacement, very subtle plasmacytic differentiation, follicular colonization, or uncommon phenotypes such as CD5 or CD10 expression. MYD88 L265P mutations were found in 11/11 LPL cases versus only 2 of 28 other SBLs included in its differential diagnosis. Mutational testing also helped to exclude other cases that would have been considered LPL in the past. The workshop also highlighted how plasmacytic differentiation can occur in chronic lymphocytic leukemia/small lymphocytic lymphoma, follicular lymphoma, SOX11 negative MCL, and particularly in marginal zone lymphomas, all of which can cause diagnostic confusion with LPL. The cases also highlighted the difficulty in distinguishing lymphomas with marked plasmacytic differentiation from plasma cell neoplasms. Some SBLs with plasmacytic differentiation can be associated with amyloid, other immunoglobulin deposition, or crystal-storing histiocytosis, which may obscure the underlying neoplasm. Finally, although generally indolent, LPL may transform, with the workshop cases suggesting a role for TP53 abnormalities.

A 70-Year-Old Man With Large Cervical and Mediastinal Lymphadenopathies

We present a case of a 70-year-old man with enlarged mediastinal and cervical lymph nodes that provided interesting radiologic and pathologic observations. The 70-year-old black man was found to have enlarged mediastinal lymph nodes. He had symptoms of atypical chest pain and generalized weakness for 2 weeks prior to the diagnosis. He denied shortness of breath, fever, chills, or night sweats. He was treated for hypertension and onychomycosis. Basic laboratory findings were within normal limits. Pulmonary function tests at the time of presentation showed FEV1, FVC, and FEV1/FVC ratio of 123% predicted, 133% predicted, and 0.7, respectively. Meanwhile, total lung capacity and carbon monoxide diffusing capacity were 103% and 107% predicted, respectively. Two weeks before he presented to our institution, the patient underwent bronchoscopy with transbronchial biopsies of the right lower lobe and endobronchial ultrasound-guided transbronchial needle aspiration of the right hilar lymph nodes.

Natural history and outcomes in localised immunoglobulin light-chain amyloidosis: a long-term observational study

BACKGROUND

Localised immunoglobulin light-chain amyloidosis, involving one type of tissue, is rare. Little systematic data exists regarding clinical presentations, course or outcomes, or risk of progression to systemic amyloidosis. We aimed to report clinical features and outcomes of a large series of patients with localised light-chain amyloidosis.

METHODS

We examined data for all patients with localised amyloidosis who were diagnosed, assessed, and followed at the UK National Amyloidosis Centre (NAC) between Jan 2, 1980, and Dec 15, 2011, from the NAC database and written records. The inclusion criteria was the presence of biopsy sample proven localised amyloidosis classified as biopsy proven amyloid deposition confined to one site or tissue proven by histology of the tissue examined), without any evidence of vital organ involvement, which was defined as cardiac, renal, or liver involvement or peripheral or autonomic neuropathy and treatment naive.

FINDINGS

We identified 606 patients with biopsy proven localised amyloidosis (likely light-chain type in 98%) from 5050 newly diagnosed patients with all types of amyloidosis. Median age was 59·5 years (IQR 50·2-74·5). The most common sites included bladder (95; 16%), laryngeal or tonsillar (92; 15%), cutaneous (84; 14%), and pulmonary nodular (47; 8%). 121 (20%) had a monoclonal immunoglobulin or abnormal circulating free light chains. At median follow-up of 74·4 months (IQR 37·2-132·0), seven (1%) patients progressed to systemic immunoglobin light-chain amyloidosis. 270 (51%) patients had one repeated treatment intervention and 112 (21%) had more than one repeated treatment interventions (predominantly localised debulking). The estimated 5-year overall survival was 90·6% (95% CI 87·7-92·9) and 10-year overall survival was 80·3% (75·1-84·1). In patients aged 70 years or older, median overall survival was 12·1 years (95% CI 10·5-13·7).

INTERPRETATION

Localised immunoglobulin light-chain amyloidosis has an excellent prognosis with no apparent effect on life expectancy. Evolution into systemic immunoglobulin light chain amyloidosis is very rare.

FUNDING

None.

Localized lymph node light chain amyloidosis

Immunoglobulin-derived light chain amyloidosis can occasionally be associated with localized disease. We present a patient with localized lymph node light chain amyloidosis without an underlying monoclonal protein or lymphoproliferative disorder and review the literature of lymph node amyloidosis discussing work-up and risk factors for systemic progression.

Adnexal mass secondary to extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) with associated amyloid deposition

Systemic amyloid light chain amyloidosis (AL amyloidosis) is usually seen in association with a plasma cell disorder. Amyloid deposition associated with extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) is a rare phenomenon that is not typically associated with systemic AL amyloidosis. We describe the unusual case of a patient with an adnexal mass secondary to MALT lymphoma with associated amyloid deposition.

Monoclonal light chain deposits within the stomach manifesting as immunotactoid gastropathy

Immunotactoid deposits are defined by their ultrastructural appearance and are characterized by microtubular or cylindrical structures typically measuring greater than 30 nm in diameter. Although a rare entity, immunotactoid deposition most often manifests as immunotactoid glomerulopathy and is associated with underlying lymphoplasmacytic disorders. Corneal immunotactoid deposition known as immunotactoid keratopathy has also been reported in patients with paraproteinemia. Here, we describe the first reported case of immunotactoid deposition in the stomach. The deposits were composed solely of kappa immunoglobulin light chains without significant lambda light chain or immunoglobulin heavy chain components. The patient displayed no renal signs or symptoms, and additional thorough clinical examination failed to detect any evidence of a paraproteinemia or plasma cell dyscrasia. Thus, the gastric immunotactoid deposits in this case appear to be an isolated finding of light chain deposition, of which the significance and etiology are unclear.

Clinical diagnosis and typing of systemic amyloidosis in subcutaneous fat aspirates by mass spectrometry-based proteomics

Examination of abdominal subcutaneous fat aspirates is a practical, sensitive and specific method for the diagnosis of systemic amyloidosis. Here we describe the development and implementation of a clinical assay using mass spectrometry-based proteomics to type amyloidosis in subcutaneous fat aspirates. First, we validated the assay comparing amyloid-positive (n=43) and -negative (n=26) subcutaneous fat aspirates. The assay classified amyloidosis with 88% sensitivity and 96% specificity. We then implemented the assay as a clinical test, and analyzed 366 amyloid-positive subcutaneous fat aspirates in a 4-year period as part of routine clinical care. The assay had a sensitivity of 90%, and diverse amyloid types, including immunoglobulin light chain (74%), transthyretin (13%), serum amyloid A (%1), gelsolin (1%), and lysozyme (1%), were identified. Using bioinformatics, we identified a universal amyloid proteome signature, which has high sensitivity and specificity for amyloidosis similar to that of Congo red staining. We curated proteome databases which included variant proteins associated with systemic amyloidosis, and identified clonotypic immunoglobulin variable gene usage in immunoglobulin light chain amyloidosis, and the variant peptides in hereditary transthyretin amyloidosis. In conclusion, mass spectrometry-based proteomic analysis of subcutaneous fat aspirates offers a powerful tool for the diagnosis and typing of systemic amyloidosis. The assay reveals the underlying pathogenesis by identifying variable gene usage in immunoglobulin light chains and the variant peptides in hereditary amyloidosis.

Leukocyte cell-derived chemotaxin 2 (LECT2)–associated amyloidosis is a frequent cause of hepatic amyloidosis in the United States

Leukocyte cell-derived chemotaxin-2–associated amyloidosis (ALect2) is a common cause of systemic amyloidosis involving the liver. Recognition and accurate diagnosis of hepatic ALect2 amyloidosis is essential for accurate management of patients with hepatic amyloidosis.

Exploring the amyloid proteome in immunoglobulin-derived lymph node amyloidosis using laser microdissection/tandem mass spectrometry

Amyloidosis affecting lymph nodes (LN) may occur in the setting of systemic amyloidosis or as an entity localized to the site of production (peritumoral). Why some LN amyloid remains peritumoral is unknown. We speculated that the composition of amyloid in these two presentations differs. We analyzed the amyloid proteome in LN amyloid samples to identify differences between the systemic and peritumoral subtypes. In immunoglobulin-derived LN amyloidosis (N = 26), 70% had heavy chain amyloid (AH or mixed AH/AL). True localized LN amyloidosis was rare, with only 2 patients without a monoclonal protein component. Nineteen patients (73%) had typical amyloid syndromes (100% of AL vs 67% of AH/AL, P = 0.02). A trend to improved survival for the AH/AL group in comparison to AL (median 5-year survival 48 vs. 19 months, P = 0.06) was seen. Mass spectrometric amyloid analysis is a powerful tool for characterizing amyloid and may provide additional prognostic information.