Answer

From the question on page 138

Immunohistochemical stains for crystal violet, congo red and thioflavine T were positive (figure 1), with no significant staining for transthyretin or amyloid A. Multiple myeloma screening, including bone marrow biopsy, was unremarkable. Given the abundance of plasma cells on biopsy and absence of underlying chronic disease, the diagnosis of primary mediastinal amyloid was made. The patient is currently receiving cyclophosphamide and dexamethasone under the care of the Haematology unit. While immunohistochemical staining for amyloid …