Significance of epithelial cell clusters in pseudomyxoma peritonei.
BACKGROUND
Pseudomyxoma peritonei (PMP) is a rare clinical syndrome characterised by distension of the peritoneum by jelly-like ascites. Cytological evaluation of peritoneal fluid is often an initial diagnostic test for possible ovarian and/or appendiceal primary tumours.


OBJECTIVE
The present work was conducted to study the usefulness of peritoneal fluid cytomorphology in the early diagnosis of PMP and to evaluate the significance of the presence of epithelial cell (EC) clusters and their prognostic implications.


METHODS
We evaluated the detailed cytological features of 21 cases of PMP retrospectively. Both conventional and liquid-based cytology smears of peritoneal fluid were reviewed, cytological features were compared with histological findings and cases were classified into disseminated peritoneal adenomucinosis (DPAM) and peritoneal mucinous carcinomatosis (PMCA).


RESULTS
In our study, the common causes of PMP were primary gastrointestinal malignancies (appendix and colorectal, 57.14%), followed by primary ovarian mucinous neoplasms (28.57%) and synchronous ovarian and appendicular tumours (14.28%). Thick mucinous material was present in all cases (100%). ECs were present in 18 of 21 (85.17%) patients, with mild nuclear atypia in the majority of cases. Histiocytes, mesothelial cells and fibroblast-like, spindle-shaped cells with entrapped mucin were also noted in the background. The cases of PMCA showed greater numbers of EC clusters in cytology smears and these patients had recurrent episodes of PMP.


CONCLUSIONS
On cytomorphology, high-grade tumours were more cellular and frequently showed EC clusters with moderate to severe atypia, prominent nucleoli and mitosis, and were more prone to PMCA.
Department of Cytopathology and Gynaecological Pathology, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
R K
RK
Badyal
Department of Cytopathology and Gynaecological Pathology, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
A
A
Khairwa
Department of Cytology, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
A
A
Rajwanshi
Department of Cytology, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
R
R
Nijhawan
Department of Cytology, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
S
S
Radhika
Department of Cytology, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
N
N
Gupta
Department of Cytopathology and Gynaecological Pathology, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
P
P
Dey
D002288:Adenocarcinoma, Mucinous / Q000175:diagnosis / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001063:Appendiceal Neoplasms / Q000175:diagnosis* / Q000473:pathology; D001202:Ascitic Fluid / Q000473:pathology; D003581:Cytodiagnosis; D003937:Diagnosis, Differential; D004847:Epithelial Cells / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010051:Ovarian Neoplasms / Q000175:diagnosis* / Q000473:pathology; D010534:Peritoneal Neoplasms / Q000175:diagnosis* / Q000473:pathology; D011553:Pseudomyxoma Peritonei / Q000175:diagnosis* / Q000473:pathology
cytology; effusion; mucinous neoplasm; pseudomyxoma peritonei