Be. Halliday et al., FINE-NEEDLE ASPIRATION CYTOLOGY OF AMYLOID ASSOCIATED WITH NONNEOPLASTIC AND MALIGNANT LESIONS, Diagnostic cytopathology, 18(4), 1998, pp. 270-275
To assess the value of fine-needle aspiration (FNA) cytology for the d
iagnosis of amyloid, we retrospectively studied all FNA cases diagnose
d as having amyloid during a 6-yr period (1990-1996). FNA was performe
d on both superficial and deep locations. A total of 6 cases containin
g amyloid was studied, including primary medullary thyroid carcinoma,
metastatic medullary thyroid carcinoma to a vertebrae, multiple myelom
a, squamous-cell carcinoma of the lung metastatic to a hilar lymph nod
e, primary pulmonary amyloid, and amyloid tumor in a vertebral body in
a patient with primary systemic amyloidosis. Despite the location or
disease association, the cytologic appearance of amyloid in all cases
was similar. On Diff-Quik stain, amyloid appeared as amorphous, irregu
lar, waxy, basophilic to metachromatic clumps of material. Papanicolao
u stain revealed cyanophilic to organophilic clumps of material with o
ccasional prominent fissures. In all 6 cases, amyloid was confirmed by
Congo red stain and in 3 cases by a thioflavin T stain. In 4 of the 6
cases (67%), amyloid was associated with an underlying malignancy. In
3 cases malignant cells were admixed with the amyloid, and in another
case malignancy was present at a distant site. We conclude that FNA b
iopsy is a helpful initial procedure for the evaluation of patients wi
th amyloid deposits. The clinical implications of amyloid found in any
particular body site include both benign and malignant conditions. Th
e presence of an associated neoplasm must be especially considered in
the differential diagnosis of amyloid deposits. (C) 1998 Wiley-Liss, I
nc.