A 61 year-old female presented with abdominal pain, rectal bleeding, mucus
discharge, tenesmus and constipation. Rectal examination and proctoscopy de
monstrated rectal stenosis at 5 cm from the anal verge. Transrectal ultraso
nography detected a capsulated lesion as a mesenchymal rectal tumor, Comput
ed tomography and endorectal magnetic resonance detected a mesenchymal lesi
on in the lower-middle rectal thirds. Serum TPA, GICA, SCC and CYFRA were p
athological. At surgery the tumour was fixed to the levator ani muscle with
rectal folding. Frozen Sections of the levator ani muscle biopsies reveale
d cloacogenic tumour. Abdominoperineal resection was performed. The rectal
lesion was cloacogenic carcinoma at 9 cm from the dentate line (pT4 pN0; Ki
67 35%; CD31 181 vessels/mm(2)). Adjuvant radio-chemotherapy was performed,
The patient is alive and disease free at 19 months. Extra-anal cloacogenic
tumours are an unusual finding. Perhaps cloacal cells were originally pres
ent in the rectal wall, but secondary rectal involvement by cloacal remnant
from the levator ani muscle cannot be excluded.