Pleural, Peritoneal, and Pericardial Effusions
Fig. 19.124 Smear of pleural effusion depicting large-cell lymphoma.
The amorphous background particles of nuclear material are due to necrosis
of the lymphoma cells (Papanicolaou x HP). Copyright 1993 American
Society of Clinical Pathologists.
Fig. 19.126 Smear of pleural effusion depicting cells of well-differentiated
small-cell lymphocytic lymphoma exhibiting coarse clumps of chromatin,
so-called cellules grumelées (clotted cells) (Papanicolaou x OI).
Fig. 19.125 Smear of pleural effusion depicting cells of Burkitt lymphoma.
Most of the lymphoma cells in this field are necrotic, appearing as pale blobs
in the background, or their nuclei have fragmented into tiny cyanophilic
particles (mercury drop karyorrhexis). At first glance, these necrotic cells
resemble neutrophils. This patient had not been treated (Papanicolaou x LP).
frequently exhibit necrosis, which may be widespread, a fea-
ture rarely observed with carcinomas. Cellular necrosis may be
seen in several forms: obvious necrosis of entire cells with sub-
sequent disintegration to form a granular background (see Fig.
19.124), and fragmentation of nuclei to form tiny, round, cyan-
ophilic cytoplasmic particles reminiscent of a dispersed drop
of mercury, so-called mercury drop karyorrhexis (Fig. 19.125).
Cells exhibiting mercury drop karyorrhexis may be mistaken for
neutrophilic leukocytes. It has been suggested that this type of
necrosis is caused by chemotherapy; however, we have observed
it on several occasions before treatment was begun.71
Low-grade lymphomas are exemplified by small-cell lym-
phocytic lymphoma, which is composed of cells that in routine
preparations are morphologically indistinguishable from nor-
mal lymphocytes; such cells may also be seen with chronic lym-
phocytic leukemia. Demonstrating the neoplastic nature of these
cells may require flow cytometry to show their monoclonality.
Spriggs and Boddington illustrated a distinctive clumping of
chromatin in cells of chronic lymphocytic leukemia in pleural
fluids (Fig. 19.126).9,14 Cells with these clumps of chromatin,
Fig. 19.127 Smear of pleural effusion depicting cells of acute
myelogenous leukemia. Leukemic cells with their rather pale, neatly round
nuclei dominate the picture (Papanicolaou x MP).
likened to clots, have been referred to as cellules grumelees
(clotted cells).242 The phenomenon seems to be virtually con-
fined to cells of low-grade lymphocytic lymphoma or chronic
lymphocytic leukemia, and its appearance can be influenced by
the method of fixing the smear. It has been shown to be more
likely to occur in methanol-fixed smears, the usual fixative for
Romanowsky-stained smears, although it has been illustrated in
a Papanicolaou-stained smear that presumably was fixed with
ethanol.9 We have also observed the phenomenon in toluidine
blue-stained wet films.
Cells of all types of leukemia may be found in serous effusions
(Figs 19.127 and 19.128). Their recognition as to type according
to the usual morphologic criteria featured in atlases of hema-
tology is best accomplished by using air-dried Romanowsky-
stained smears. As in lymphomatous effusions, necrosis may be
Myeloma cells are rarely seen in serous effusions, but when
they are present they are usually numerous.243,244 They possess
the distinguishing morphologic features of plasma cells, but are
larger (Fig. 19.129), often multinucleated, and have prominent