CORRELATION OF LIGHT-MICROSCOPIC, IMMUNOCYTOCHEMICAL AND ULTRASTRUCTURAL CYTOMORPHOLOGY OF ANAPLASTIC LARGE-CELL KI-1 LYMPHOMA, AN ACTIVATED LYMPHOCYTE PHENOTYPE - A CASE-REPORT
Jc. Papadimitriou et al., CORRELATION OF LIGHT-MICROSCOPIC, IMMUNOCYTOCHEMICAL AND ULTRASTRUCTURAL CYTOMORPHOLOGY OF ANAPLASTIC LARGE-CELL KI-1 LYMPHOMA, AN ACTIVATED LYMPHOCYTE PHENOTYPE - A CASE-REPORT, Acta cytologica, 40(6), 1996, pp. 1283-1288
BACKGROUND: Anaplastic large cell Ki-1 lymphoma has been proposed to b
e a neoplasm of activated lymphocytes, mostly of T-cell origin. CASE:
A previously healthy 12-year-old boy presented with a two-month histor
y of a rapidly growing hard palate mass that involved the nasal cartil
age and extended to the floor of the right orbit. By light microscopy
(LM) the aspirates were very cellular, containing single, pleomorphic
cells and occasional cellular aggregates. The cells showed distinct po
larity, with the large, anaplastic nucleus at one end and the tapering
cytoplasm, including a prominent paranuclear halo (or ''hof''), at th
e other end (''hand mirror'' appearance). The cytoplasmic border showe
d prominent ruffling, concentrated at the two poles of the cells and c
orresponding to the areas of the protopod and uropod. Immunocytochemic
ally (ICC) the cells were positive for Ki-1, epithelial membrane antig
en and UCHL-1, all of which showed both membrane positivity along with
Golgi area staining. LCA showed variable membrane staining. Ultrastru
cturally (electron microscopy [EM]) the polarity was recapitulated, wi
th an eccentric, horseshoe-shaped nucleus partially enclosing a promin
ent Golgi complex with associated centrosomes and asymmetric plasma me
mbrane ruffling. CONCLUSION: All three levels of examination (LM, ICC
and EM) revealed tumor cell features corresponding to the phenotype of
the activated lymphocyte. These features are characteristic, thus all
owing the diagnosis of Ki-1 anaplastic lymphoma by fine needle aspirat
ion cytology.