Cytological characteristics of atypical cells in endoscopic ultrasound-guided fine-needle aspiration specimens obtained from the pancreas

Novel Cytological Diagnostic Scoring System for Pancreatic Specimens Obtained by Endoscopic Ultrasound-Guided Fine Needle Aspiration

“…We had previously reported that atypical pancreatobiliary glands with pink mucus (probably sulfomucin) suggested malignancy, and yellow-orange mucin (probably neutral mucin) suggested benignity. 21 In the present study, pink intracellular mucus was detected only in malignant cases and not in benign cases, but its presence in malignant cases was low (12%-44%). These results indicate that pink intracellular mucus possesses high speci city and low sensitivity to distinguish malignant and benign tumors.…”

“…The presence or absence of the following 20 cytological indices was evaluated by 7 reviewers based on the results of previous studies: 18,21 (1) necrotic background ( Fig. 1A), (2) mucus background ( Fig.…”

“…18 The indices related to mucins are speci c to malignant cells of the pancreas based on our previous study. 21 Usefulness of 20 indices to distinguish malignant and benign cases Seven reviewers, including 4 cytotechnologists and 3 medical doctors, evaluated 20 cytological indices using pancreatic specimens obtained by EUS-FNA (malignant, n=111; benign, n=31). Figure 5 shows the percentages of the presence of these 20 indices among the included specimens.…”

Cytological scoring for pancreatic specimens obtained by endoscopic ultrasound‐guided fine needle aspiration

“…The following 20 cytological indices were evaluated by seven reviewers, based on the results of previous studies 19,25 . In general, the following indices cytologically indicate malignancy: (1) necrotic background (Figure 1A); (2) mucinous background (Figure 1B); (3) hypercellularity (Figure 1C), a state in which cell clumps and isolated scattered cells are observed in the entire field of view at low magnification; (4) two‐cell pattern (Figure 1D) not including contamination of digestive epithelial cells; (5) irregular structure (Figure 2A) relating mainly to papillary structure; (6) irregular cell polarity (Figure 2B) showing an irregular arrangement of cells; (7) overlapping (Figure 2C) indicated by the presence of overlapping cells; (8) decreased cell adhesion (Figure 2D); (9) irregular nuclei (Figure 3A) indicating cytoplasmic inclusions in the nucleus, and distorted nuclei and nuclear grooves; (10) hyperchromasia (Figure 3B); (11) nuclear membrane thickening (Figure 3C); (12) anisonucleosis (Figure 3D), involving a mixture of various nuclear sizes; (13) prominent nucleoli (Figure 3E); (14) increased mitosis (Figure 3F), indicated by the presence of an increased number of mitotic cells; (15) unclear cell boundaries (Figure 4A); (16) high N/C ratio (Figure 4B) compared to normal pancreatic duct epithelial cells; (17) pink intracellular mucus (Figure 4C); (18) orange‐yellow intracellular mucus (Figure 4D); (19) cannibalism (Figure 4E); and (20) keratinisation (Figure 4F), an important cytological feature for predicting adenosquamous carcinoma.…”

“…The presence of a two‐cell pattern, which is the coexistence of malignant and benign cells (Figure 1D), aids in identifying malignant cells with relatively lower atypia. Based on our previous study, the indices related to mucins are specific to malignant cells of the pancreas 25 . The useful indices to distinguish malignant and benign cases should have the following properties: (1) high incidence rate in malignant cases; (2) statistically significant difference ( p < 0.0001) between malignant and benign cases; and (3) reproducibility in various groups with different backgrounds and skills.…”