Australian Society of CytologyCase of the Month
September 2003 - Answer and Discussion
Moderate to poorly differentiated adenocarcinoma consistent with rectal primary.
Answer
The background of the smears is degenerate and somewhat mucinous.
The smears contain numerous cohesive groups of atypical cells, some with a poorly developed acinar pattern and others appearing columnar.
Discussion
About 25% of Ca rectum show direct involvement with the vagina, cervix and endometrial mucosa by metastatic implantation or direct spread.
Tumour diathesis is often present due to mucosal ulceration with haemorrhage and necrosis.
Adenocarcinoma of rectal origin is composed of tall columnar cells sometimes arranged in palisade pattern. Basal nuclei are very hyperchromatic often with coarse chromatin and prominent nucleoli.
These cells may be interpreted as those of endocervical adenocarcinoma however cells from colorectal Ca contain much coarser chromatin granules.
References
- Ng Alan B. and Abdul-Karim F.W: Chapter 36. Diagnostic Cytopathology. W.Gray.
- Saigo P.E: Chapter 13: Comprehensive Cytopathology: Bibbo
