**7.1 Nodular pulmonary amyloidosis**

Nodular amyloid deposits involving the lung are usually an incidentaloma on chest imaging and usually consist of AL light chain or mixed AL-AH light chainheavy chain [68, 69]. Nodular amyloidosis has been associated with mucosa associated lymphoid tissue (MALT) and Sjogren disease [68]. In a study of 49 individuals with nodular AL amyloidosis, surgical resection and systemic chemotherapy

were the major forms of treatment [64]. In fact, conservative excision in nodular AL amyloidosis presents with a great prognosis, although intervention is rarely required as a whole.

## **7.2 Diffuse alveolar amyloidosis**

Presence of amyloid deposits on the alveolar walls and adjoining blood vessels signifies diffuse alveolar amyloidosis [70–72]. Since pulmonary impairment is not prominent in diffuse alveolar amyloidosis, it is often observed as a finding of postmortem studies [73]. Positron emission tomography using radiolabeled florbetapir is one of the modalities that can help identify the diffuse alveolar variant of amyloidosis [74]. Diffuse alveolar amyloidosis has a progressive course of interstitial lung disease involving an infiltrative imaging pattern and dyspnea [75].

Diffuse alveolar amyloidosis is most commonly a manifestation of systemic AL amyloidosis, which is why treatment takes the form of targeting the underlying systemic amyloidosis. Burden reduction of free light chain is deemed to be central principle of treatment. Chemotherapy like low-dose Melphalan derived for multiple myeloma currently drives the treatment modalities used for diffuse alveolar amyloidosis [76–78]. Prednisolone is another medication used for treatment purposes. However, it is important to fashion treatment on a personalized basis based on patient needs. Pulmonary amyloidosis especially complicates the scenario when diffusion capacity reduces to less than 50%, although stem cell transplantation is an option in these cases [79]. Lung transplant is yet another option to treat isolated lung amyloidosis [80].

## **7.3 Laryngeal amyloidosis**

Usually localized in nature, laryngeal amyloidosis is manifested by amyloid deposits superior to the glottis. The larynx is the most common location for isolated amyloid deposition in the head and neck, and symptomatically presents with stridor, dyspnea, and hoarseness [81]. Larger lesions are often surgically removed with an endoscopic excision or laryngofissure [82, 83]. Smaller lesions can be treated with carbon dioxide laser evaporation [84, 85].

## **7.4 Tracheobronchial amyloidosis**

Tracheobronchial amyloidosis is characterized by submucosal plaques with occasional involvement of the trachea and larynx [86, 87]. Cough, dyspnea, and hemoptysis are common manifestations, with tracheal and bronchial thickening and calcifications being diagnostic markers on CT [88, 89]. Stenting is also used to prevent airway collapse in an already compromised respiratory circuit. Although treatment modalities for tracheobronchial amyloidosis are limited, systemic chemotherapy is sometimes used [89]. Tracheobronchial involvement can be symptomatically treated with debridement, bronchoscopic resection, and external beam radiation [90, 91].

#### **7.5 A peek into the future**

Agents are being developed that aim to help stabilize amyloid in their native morphology and slow down or even halt fibril deposition. Glycosaminoglycans (GAG)-like molecules inhibitors and Secreted Aspartyl Proteinase (SAP)-binding inhibitors are currently being developed. GAG binding to amyloid enhances amyloid fibril deposition, while SAP potentiates amyloidosis [92, 93]. Like mentioned earlier, it is paramount to mold each treatment plan according to the recipient to best suit the patient's needs and goals of care.

**33**

**Author details**

and Matthew Zabel\*

provided the original work is properly cited.

*Amyloidosis: Systems-Based Therapies*

*DOI: http://dx.doi.org/10.5772/intechopen.85201*

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

Eileen Ly, Anu Stephen, Yasmeen Alhomsy, Asal Homayouni, Joshua Fisher, Kayla Sheehan, Prashanth Venkataraman, Quinto Gesiotto, Matthew Habib

College of Medicine, California Northstate University, Elk Grove, CA, USA

\*Address all correspondence to: matthew.zabel9352@cnsu.edu

*Amyloidosis: Systems-Based Therapies DOI: http://dx.doi.org/10.5772/intechopen.85201*

*Amyloid Diseases*

required as a whole.

**7.2 Diffuse alveolar amyloidosis**

**7.3 Laryngeal amyloidosis**

with carbon dioxide laser evaporation [84, 85].

best suit the patient's needs and goals of care.

**7.4 Tracheobronchial amyloidosis**

**7.5 A peek into the future**

were the major forms of treatment [64]. In fact, conservative excision in nodular AL amyloidosis presents with a great prognosis, although intervention is rarely

Presence of amyloid deposits on the alveolar walls and adjoining blood vessels signifies diffuse alveolar amyloidosis [70–72]. Since pulmonary impairment is not prominent in diffuse alveolar amyloidosis, it is often observed as a finding of postmortem studies [73]. Positron emission tomography using radiolabeled florbetapir is one of the modalities that can help identify the diffuse alveolar variant of amyloidosis [74]. Diffuse alveolar amyloidosis has a progressive course of interstitial lung

Diffuse alveolar amyloidosis is most commonly a manifestation of systemic AL amyloidosis, which is why treatment takes the form of targeting the underlying systemic amyloidosis. Burden reduction of free light chain is deemed to be central principle of treatment. Chemotherapy like low-dose Melphalan derived for multiple myeloma currently drives the treatment modalities used for diffuse alveolar amyloidosis [76–78]. Prednisolone is another medication used for treatment purposes. However, it is important to fashion treatment on a personalized basis based on patient needs. Pulmonary amyloidosis especially complicates the scenario when diffusion capacity reduces to less than 50%, although stem cell transplantation is an option in these cases [79]. Lung transplant is yet another option to treat isolated lung amyloidosis [80].

Usually localized in nature, laryngeal amyloidosis is manifested by amyloid deposits superior to the glottis. The larynx is the most common location for isolated amyloid deposition in the head and neck, and symptomatically presents with stridor, dyspnea, and hoarseness [81]. Larger lesions are often surgically removed with an endoscopic excision or laryngofissure [82, 83]. Smaller lesions can be treated

Tracheobronchial amyloidosis is characterized by submucosal plaques with occasional involvement of the trachea and larynx [86, 87]. Cough, dyspnea, and hemoptysis are common manifestations, with tracheal and bronchial thickening and calcifications being diagnostic markers on CT [88, 89]. Stenting is also used to prevent airway collapse in an already compromised respiratory circuit. Although treatment modalities for tracheobronchial amyloidosis are limited, systemic chemotherapy is sometimes used [89]. Tracheobronchial involvement can be symptomatically treated with debridement, bronchoscopic resection, and external beam radiation [90, 91].

Agents are being developed that aim to help stabilize amyloid in their native morphology and slow down or even halt fibril deposition. Glycosaminoglycans (GAG)-like molecules inhibitors and Secreted Aspartyl Proteinase (SAP)-binding inhibitors are currently being developed. GAG binding to amyloid enhances amyloid fibril deposition, while SAP potentiates amyloidosis [92, 93]. Like mentioned earlier, it is paramount to mold each treatment plan according to the recipient to

disease involving an infiltrative imaging pattern and dyspnea [75].

**32**
