NK/T-cell lymphoma.

In this case report, a 61-year-old male presented with odynophagia and ulceration in palatum durum after inhalating dust from machinery containing a weak acid. It was at first diagnosed as an acidic ulcer due to two biopsies verifying this. Because of progressing ulceration a third biopsy was taken - this time with the diagnosis extranodal NK/T-cell lymphoma, nasal type. This illustrates the diagnostic challenges of the illness, typically requiring multiple biopsies, and one should have this differential diagnosis in mind in case of progressing ulceration.

Amyloidosis is a disease with many faces.

Amyloidosis is a severe disease caused by protein misfolding and deposition in tissues and organs. Thirty-eight different proteins are known to be amyloidogenic. Amyloidosis is categorized into inherited or acquired, and systemic or localized. Light-chain (AL)- and transthyretin (ATTR) amyloidosis are the two most common subtypes. Awareness, early diagnosis, accurate subtyping and relevant treatment are crucial for the management. Novel therapies of systemic AL and ATTR amyloidosis have considerably improved outcome and survival. The aim of this review is to increase awareness and knowledge on diagnosing amyloidosis.

Immunoelectron microscopy and mass spectrometry for classification of amyloid deposits.

Amyloidosis is a shared name for several rare, complex and serious diseases caused by extra-cellular deposits of different misfolded proteins. Accurate characterization of the amyloid protein is essential for patient care. Immunoelectron microscopy (IEM) and laser microdissection followed by tandem mass spectrometry (LMD-MS) are new gold standards for molecular subtyping. Both methods perform superiorly to immunohistochemistry, but their complementarities, strengths and weaknesses across amyloid subtypes and organ biopsy origin remain undefined. Therefore, we performed a retrospective study of 106 Congo Red positive biopsies from different involved organs; heart, kidney, lung, gut mucosa, skin and bone marrow. IEM, performed with gold-labelled antibodies against kappa light chains, lambda light chains, transthyretin and amyloid A, identified specific staining of amyloid fibrils in 91.6%; in six biopsies amyloid fibrils were not identified, and in two, the fibril subtype could not be established. LMD-MS identified amyloid protein signature in 98.1%, but in nine the amyloid protein could not be clearly identified. MS identified protein subtype in 89.6%. Corresponding specificities ranged at organ level from 94-100%. Concordance was 89.6-100% for different amyloid subtypes. Importantly, combined use of both methods increased the diagnostic classification to 100%. Some variety in performances at organ level was observed.