PMC9208982_01
A well-circumscribed nodule within the placenta (hematoxylin and eosin).
CRIPA2022-1966025.001.jpg
PMC9208982_01_CRIPA2022-1966025.001.jpg
fig1
The microscopic examination of the nodule revealed a well-circumscribed lesion (Figure 1), surrounded by a fibrous capsule and composed of polygonal cells, with clear eosinophilic cytoplasm and small, round to ovoid nuclei.
Trabecular-like structures of polygonal cells, with rare extramedullary hematopoiesis (hematoxylin and eosin).
CRIPA2022-1966025.002.jpg
PMC9208982_01_CRIPA2022-1966025.002.jpg
fig2
Rare foci of extramedullary hematopoiesis were observed (Figure 2).
Glycogen deposits (arrowheads) were demonstrated using Periodic Acid-Schiff (PAS) and Periodic Acid-Schiff with diastase (PAS-D) stains.
CRIPA2022-1966025.003.jpg
PMC9208982_01_CRIPA2022-1966025.003.jpg
fig3
Some cells presented eosinophilic intracytoplasmic material, consistent with glycogen deposits, demonstrated by the Periodic Acid-Schiff (PAS) and Periodic Acid-Schiff with diastase (PAS-D) stains (Figure 3).
The polygonal cells express diffusely large spectrum keratin AE1/AE3 (a) and the hepatic differentiation marker HepPar-1 (b) antibodies. Polyclonal carcinoembryonic antigen showed expression in the canalicular pole of the hepatocytes (c). Glypican-3 antibody is expressed focally (d). (Dimension in figure 4(c) corresponds to all figures).
CRIPA2022-1966025.004.jpg
PMC9208982_01_CRIPA2022-1966025.004.jpg
fig4
Kit was used for all antibodies. Keratin AE1/AE3 (Ready-to-Use, Dako, Glostrup, Denmark) and hepatocyte paraffin-1 (HepPar-1, Roche, Diegem, Belgium) were diffusely expressed in the main cells (Figures 4(a) and 4(b)). Cluster of differentiation 10 (CD10, Ready-to-Use, Agilent, Machelen, Belgium) and polyclonal carcinoembryonic antigen (pCEA, 1 : 100, VWR/Klinipath, Leuven, Belgium) (Figure 4(c)) showed focal, canalicular-like pattern of expression. Glypican-3 (Clone 1G12, Sanbio, Uden, Netherlands) was also expressed focally (Figure 4(d)).
CD31 and CD34 markers showed diffuse expression in the sinusoid-like blood vessels (a and b, respectively). Ki67/MIB1 shows an increased proliferation index strictly limited to the extramedullary hematopoiesis foci (c). Cytokeratin 7 antibody expression is absent in the hepatocytes and proves lack of portal spaces (d). (Dimension in figure 5(c) corresponds to all figures).
CRIPA2022-1966025.005.jpg
PMC9208982_01_CRIPA2022-1966025.005.jpg
fig5
Cluster of differentiation 31 (CD31, Ready-to-Use, Agilent, Machelen, Belgium) and cluster of differentiation 34 (CD34, Ready-to-Use, Roche, Diegem, Belgium) were positive in the blood vessels (Figures 5(a) and 5(b)). Ki67/MIB1 (1 : 200, Agilent, Machelen, Belgium) highlighted proliferative activity in the extramedullary hematopoiesis foci exclusively (Figure 5(c)). The cytokeratin 7 (CK 7, Ready-to-Use, Roche, Diegem, Belgium) antibody showed no expression in the lesion (Figure 5(d)).