Analysis of plasma cell clonality in localized AL amyloidosis

Localized light chain amyloidosis: A self-limited plasmacytic B-cell lymphoproliferative disorder

Immunoglobulin light chain amyloidosis can be either systemic or localized. Although these conditions share a similar name, they are strikingly different. Localized light chain amyloidosis has been challenging to characterize due to its lower incidence and highly heterogeneous clinical presentation. Here, we review the emerging literature, emphasizing recent reports on large cohorts of patients with localized amyloidosis, and provide insights into this condition's pathology and natural history. We find that patients with localized amyloidosis have an excellent prognosis with overall survival similar to that of the general population. Furthermore, the risk of progression to systemic disease is low and likely represents initial mischaracterization as localized disease. Therefore, we argue for the incorporation of more sensitive techniques to rule out systemic disease at diagnosis. Despite increasing mechanistic understanding of this condition, much remains to be discovered regarding the cellular clonal evolution and the molecular processes that give rise to localized amyloid formation. While localized surgical resection of symptomatic disease is typically the treatment of choice, the presentation of this disease across the spectrum of plasmacytic B-cell lymphoproliferative disorders, and the frequent lack of an identifiable neoplastic clone, can make therapy selection a challenge in the uncommon situation that systemic chemotherapy is required.

Sjögren syndrome-related plasma cell disorder and multifocal nodular AL amyloidosis: clinical picture and pathological findings

Background: Localized nodular deposits of AL amyloid are seen in different tissues/organs; however, the pathogenesis of this form of amyloidosis remains unclear. Recently, Sjögren syndrome combined with localized nodular AL amyloidosis has been noted. Here, we report Sjögren syndrome cases showing multifocal nodular AL amyloidosis and the followed benign course. Materials and methods: We investigated the clinical pictures and histopathological findings of three cases with both presence of Sjögren syndrome and localized nodular AL amyloidosis, paying a special attention to the distribution of amyloidoma. Results: All three cases were middle-aged females. In two of three cases localized deposits of AL amyloid preceded Sjögren syndrome. Amyloidoma was detected in scalp, eyelid, cheek, larynx, trachea, lung and breast, and around these amyloid-deposited lesions infiltration of plasma cells was seen. Pulmonary amyloidosis was consistently accompanied with parenchymal cystic lesions, but this amyloidosis did not produce any significant respiratory symptoms. Some of large pulmonary amyloidomas showed cavity formation and subsequent shrinkage. In two cases amyloid deposition was found on gastric mucosa. Two cases received small doses of oral prednisone, with no further appearance of amyloidoma. Conclusion: Sjögren syndrome-related plasma cell disorder may be responsible for the formation of this unique multifocal nodular AL amyloidosis.

A Rare Presentation of Nodular Amyloidosis on the Lower Back

Primary localized cutaneous amyloidosis (PLCA) occurs when amyloid is deposited only within the skin and there is no evidence of systemic involvement. Nodular amyloidosis is the rarest subtype of PLCA. It typically involves the acral regions but can sometimes present on the head and neck. The condition usually presents clinically as a single tan or yellow nodule or plaque that may appear waxy. Herein, we present a rare case of a 66-year-old man with nodular amyloidosis on the lower back.

Localized Amyloidosis of the Upper Aerodigestive Tract: Complex Analysis of the Cellular Infiltrate and the Amyloid Mass

Objectives

The aim of this study was to analyse the composition of amyloid mass and the plasmacytic infiltrate of localized amyloidosis of the upper aerodigestive tract.

Methods

Biopsy materials were studied by light microscopy, immunohistochemistry (IHC), and mRNA in situ hybridization (mRNA-ISH). The amyloid mass was also analysed with high-performance liquid chromatography mass spectrometry- (HPLC-MS-) based proteomics.

Results

Nodular and diffuse forms of amyloid deposition were detected. IHC analysis revealed λ-light chain (LC) in two cases, κ-LC in one case. The remaining two were positive with both. Proteins, well known from other amyloidoses like amyloid A (AA), prealbumin/transthyretin (PA), apolipoprotein A-I (ApoAI), and amyloid P component (APC), and also keratin were found with variable intensities in the cases. HPLC-MS revealed dozens of proteins with both LCs in all the lesions but sometimes with surprisingly small intensities. mRNA-ISH analysis revealed identical λ and κ dominance and only one normal κ/λ cell ratio.

Conclusion

Cellular infiltrate and protein components in the amyloid showed congruent results in all but one case. The only exception with normal cell ratio and λ-dominant amyloid could be originated from the different protein-secreting activity of plasma cell clones. HPLC-MS analysis explored both LCs in all the amyloid in variable amount, but other proteins with much higher intensities like keratins, apolipoprotein A-IV (ApoAIV), were also detected. Proteins like AA, PA, ApoAI, and APC, previously known about amyloid-forming capability, also appeared. This indicates that localized amyloid in the upper aerodigestive tract is not a homogenous immunoglobulin mass but a mixture of proteins. The sometimes very low light chain intensities might also suggest that not all the localized amyloidosis cases of the upper aerodigestive tract are of convincingly AL type, and the analysis of the cellular infiltrate might indicate that not all are monoclonal.

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.

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 AL amyloidosis: a suicidal neoplasm?

Although AL amyloidosis usually is a systemic disease, strictly localized AL deposits are not exceptionally rare. Such case reports form a considerable body of published articles. Although both AL amyloidosis types are formed from an N-terminal segment of a monoclonal immunoglobulin light chain, a typical localized AL amyloid differs from the systemic counterpart by the morphological appearance of the amyloid, and presence of clonal plasma cells and of giant cells. In this article it is pointed out that localized AL amyloidosis ('amyloidoma') represents a true plasma cell neoplasm and not a pseudotumor. The pathogenesis of localized AL amyloidosis may differ from that of the systemic type, a suggestion underlined by the fact that localized AL amyloidosis of kappa type is as common as that of lambda origin, in contrast to the systemic form where lambda chains constitute the overwhelming majority of cases. It is suggested that oligomeric assemblies of the produced immunoglobulin light chain are toxic to plasma cells, which in this way commit suicide.

Head and neck amyloidosis: clinicopathological features and immunohistochemical analysis of 14 cases

BACKGROUND

Amyloidosis is associated with or caused by amyloid deposition. These fibrillar proteins may be deposited extracellularly causing tissue damage or impairment.

OBJECTIVES

The aim of the study was to retrospectively review pathology archives in two oral diagnostic centers for cases fulfilling criteria of amyloidosis and to differentiate AA and AL types of amyloidosis.

METHODS

The clinicopathological features, alkaline Congo red staining, with and without pretreatment with potassium permanganate, and immunohistochemical (IHC) staining with anti-AA, anti-kappa (κ), and anti-lambda (λ) light chain antibodies were carried out and analyzed.

RESULTS

The search identified 14 cases. Ten patients were women and four were men, with a mean age of 58 years. Eleven patients had systemic involvement by amyloidosis (associated either with multiple myeloma or plasma cell dyscrasia/monoclonal gammopathies), while three presented the localized type, one of them associated with plasmacytoma. All cases showed positivity for κ or λ light chains (AL-amyloid) and presented resistance to the potassium permanganate pretreatment.

CONCLUSIONS

Our results show that the head and neck region is preferentially affected by systemic AL-amyloidosis, usually associated with plasma cell dyscrasia. Interestingly, two cases affected by inflammatory rheumatic diseases presented AL-amyloid deposition. Moreover, even after pretreatment with potassium permanganate, which was helpful in highlighting the presence of AL-amyloid, in agreement with the IHC findings, clinical classifications should be carefully made in systemic amyloidosis.

Localized amyloidosis of the genitourinary tract: report of 5 new cases and review of the literature

Primary localized amyloidosis of the genitourinary tract is a rare entity characterized by small pseudotumors localized in the renal pelvis, ureters, or bladder. Amyloid fibrils are derived from immunoglobulin light chains, but no systemic plasma cell proliferation is detected. The clinical and radiologic features mimic urinary tract cancer, and local treatment is indicated. The prognosis is excellent in most cases, although disease recurrence is possible. We report 5 new cases of localized amyloidosis of the urinary tract, with lambda (4/5), or kappa (1/5) chain amyloid protein, involving the bladder (5/5), and the ureter and renal pelvis (1/5), with multiple, bilateral lesions in 1 case. The presenting complaint was painless hematuria in 4 cases. All cases were of primary (AL)-type amyloidosis. All patients underwent extensive investigation, and none presented any signs of generalized amyloidosis. A favorable outcome was observed in every case. We performed a comprehensive review of the literature, and summarize the data.

The spectrum of localized amyloidosis: a case series of 20 patients and review of the literature

Localized deposition of amyloid may occur in individual organs, in the absence of systemic involvement. The reason for localized deposition is unknown, but it is hypothesized that deposits result from local synthesis of amyloid protein, rather than the deposition of light chains produced elsewhere. We identified 20 cases of localized amyloidosis at our institution between 1993 and 2003. There were 11 males and nine females in the group. The mean age at the time of diagnosis was 65.5 years. Organs involved included skin, soft tissues, oropharynx, larynx, lung, bladder, colon, conjunctiva, and lymph node. In six of nine patients typed, the amyloid light chain was lambda. In those patients where follow-up was available (mean 7.6 years), none developed systemic disease. Localized amyloidosis occurs in a variety of organ systems. Evolution into systemic amyloidosis was not seen in our series of patients, supporting the hypothesis of local production of amyloid protein in these cases.

A case report of dystrophic localized amyloidosis that developed in the left thigh

We report on a 50-year-old man with dystrophic localized amyloidosis who noticed a soft tumor in his left thigh about 20 years ago, after which the tumor has gradually enlarged. The multicystic tumor showed hemorrhage, hematoma, necrosis, fibrosis, and tiny nodules and various polymorphous granulomas were observed. One was rich in eosinophilic amorphous materials and cholesterol crystals, and was poor in cell reaction. Another was formed by granuloma consisting of multinucleated giant cells, foamy cells, and macrophages. Transitional granulomas between the two were also observed. The materials showed eosinophilia and red staining and apple-green birefringence in polarized light by alkaline Congo-red stain, and they were also resistant to potassium permanganate pretreatment. They were also positive for amyloid P component and consistently negative for amyloid A, kappa- and lambda-light chains, beta2-microglobulin, and transthyretin. Therefore, it was suggested that this might be an amyloid derived from the hematoma, which has not been reported to date.

Light chain amyloidosis of the urinary bladder. A site restricted deposition of an externally produced immunoglobulin

AIMS

To identify the amyloid protein in a patient with amyloidosis localised to the urinary bladder, and to see whether subtyping of the protein by sequence analysis increases the understanding of the selection of the urinary bladder as the site of amyloid deposition.

METHODS

A patient with gross haematuria and a congophilic mass in his urinary bladder was evaluated further. Characterisation of the amyloid protein was performed using conventional histological and immunohistochemical methods. Determination of the N-terminal amino acid sequence of the amyloid protein was performed using protein sequencers.

RESULTS

The patient's history, physical examination, and laboratory evaluation excluded the involvement of other organs, justifying a diagnosis of amyloidosis localised to the urinary bladder. Histological and immunological studies showed that the amyloid protein deposited in the urinary bladder of the patient was probably of the amyloid light chain type. No plasma cells or lymphocytes were seen in sections of the urinary bladder and lower ureter adjacent to the amyloid deposits. Molecular analysis showed the sequence NFMLTQPHSISGSPG, which assigned the amyloid protein to either the Vlambda(I) or the Vlambda(VI) immunoglobulin (Ig) light chain families.

CONCLUSIONS

The findings suggest that the amyloid protein in this patient originated outside the urinary bladder. The heterogeneity of the Ig proteins in known cases of amyloidosis of the lower urinary tract suggests that the amino acid residues, which determine the Vlambda subtyping, have no major role in restricting the deposited protein to the urinary bladder.

Useful polyclonal antibodies against synthetic peptides corresponding to immunoglobulin light chain constant region for immunohistochemical detection of immunoglobulin light chain amyloidosis

For the immunohistochemical detection of immunoglobulin (Ig) light chain amyloidosis on formalin-fixed, paraffin-embedded tissue sections, we prepared polyclonal antibodies against synthetic peptides corresponding to positions 118-134 of Ig lambda light chain and positions 116-133 of Ig kappa light chain. Nineteen cases of systemic Ig lambda light chain amyloidosis (Alambda amyloidosis), 10 cases of systemic Ig kappa light chain amyloidosis (Akappa amyloidosis), one case of immunohistochemically unclassified systemic amyloidosis and five cases of localized Alambda amyloidosis were tested with these antibodies. Anti-lambda (118-134) antiserum and the affinity-purified antibody both reacted with 18 of the 19 cases of systemic Alambda amyloidosis and all cases of localized Alambda amyloidosis, although the immunoexpression was somewhat variable in intensity in different areas within the same specimen in both systemic and localized amyloidosis. The signal intensities in plasma cells and serum reacted for anti-lambda (118-134) antiserum were weaker than signals obtained with commercially available anti-Ig lambda light chain antibodies. Anti-kappa (116-133) antiserum and the affinity-purified antibody reacted with nine of the 10 cases of systemic Akappa amyloidosis. We conclude that these antibodies against synthetic peptides corresponding to the Ig light chain constant region are useful for the classification of amyloidosis on formalin-fixed, paraffin-embedded tissue sections.