Abstract
Background and Study Aims: Based on the positive results of endorectal ultrasound we evaluated flexible colonic
endosonography for colonic tumors. At present there are no generally accepted indications
for this procedure. Moreover, it is unclear whether the results are valid enough to
warrant specific therapeutic interventions.
Patients and Methods: Over a one-year period we performed flexible colonic endosonography (12 MHz rotating
scanner) on 31 patients with colonic tumors. The examination was only performed when
therapeutic implications were expected (e.g. endoscopic procedure when there was no
sign of malignancy; oncological resection when there were signs of malignancy in ulcerative
colitis or familial polyposis).
Results: Of 40 tumors examined, 36 were correctly staged by endosonography, compared to postoperative
histology as the gold standard (16 of 17 adenomas, 5 of 5 pT1 carcinomas, 8 of 8 pT3
carcinomas). In two cases pT4 carcinomas were wrongly classified endosonographically
as uT3 carcinomas, because the infiltration of the visceral peritoneum was technically
not recognizable. Overall the accuracy rate of staging was 85 %. Lymph node staging
was correct in 36 of 40 patients, amounting to an accuracy rate of 90 %.
Conclusion: Because of its high accuracy rate flexible colonic endosonography has a place in
the preoperative staging of colonic tumors in selected patients, especially those
with ulcerative colitis, familial adenomatous polyposis or macroscopically suspicious
adenomas. It helps to clarify the extent (oncological resection, lymphadenectomy)
of resection required in conventional surgery and helps to avoid laparoscopic procedures
in advanced colonic cancer.
