CASE N°24 – Biliary Tract Brush Cytology – Malignant vs. Reactive cells
Cirrhotic patients, abdominal pain for about one month, ulcerative colitis.
Endoscopy: dilation of the intra and extrahepatic bile ways
Cytological material: Biliary tract, brushing
A) Papillary aggregate of neoplastic cells. Loss of honeycomb pattern, hypercromatic nuclei and anisocariosis (2).
B) macro-aggregates of neoplastic cells: prominent nuclear overlapping, loss of honeycomb, coarse chromatin (2).
C,D) macronucleoli, marked anisocariosis, clumped chromatin, high nucear/cytoplasmic ratio (2).
E) Hyperchromatic, coarse, clumped chromatin, high nucelear/cytoplasmic ratio, bile pigment (2).
Numerous aggregates of glandular epithelial cancer cells admixed with plenty of blood and bile pigment.
Positive for malignancy.
Indications of biliary cytology
The primary indication for biliary cytology is a suspected malignancy in a patient with biliary stricture (1).
Cytologic specimens from biliary tract include brushings, ERCP guided brush cytology(2) and exfoliated bile. The brushing specimen is the one with the highest accuracy(1).
Dysplasia may be present in the biliary tract. Dysplastic cells are usually arranged in clusters showing crowding and nuclear overlapping. They show significant nuclear atypia, with increased N/C ratio and chromatin abnormalities, which is however less pronounced than in adenocarcinoma(1).
Strictures of the biliary tract may be caused by adenocarcinomas. Cytologic features of malignant cells include: increased N/C ratio, chromatin clumping, nuclear molding or loss of honeycombing (1).
Marked reactive changes may be seen in brushing specimens from the biliary tract of patients with primary sclerosing cholangitis, mimicking a neoplastic process. Moreover, patients with primary sclerosing cholangitis have an increased risk of development of dysplasia and cholangiocarcinoma.
Dysplastic cell groups usually show more crowding than reactive/reparative cells and more pronounced nuclear atypia (1).
F) “normal” cells: the cells are well aligned and evenly spaced, with regular, oval nuclei (2).
G) Reactive cells: nuclear hyperchromasia, slight overlapping; the cells still have parallel alignment (2).
2) Manjunat S. Vadmal, M.D., Susan Byrne-Semmelmeier, C.T.(ASCP) et al.Biliary Tract Brush Cytology.Acta Cytol. 200;44:533-538