12th Ljudevit Jurak International Symposium on
Comparative Pathology
Zagreb
June 1-2, 2001
ABSTRACT
ADDITIONAL HISTOLOGIC CRITERIA FOR THE DIAGNOSIS OF COLORECTAL CARCINOMA IN ENDOSCOPIC BIOPSIES 
A. Cerar, N. Zidar
Institute of Pathology, Medical Faculty, Ljubljana, Slovenia
In endoscopic biopsies, desmoplastic stroma (DS) and tumor invasion of the submucosa (InvSM) that accompany dysplastic epithelium, are considered to be histologic changes diagnostic for colorectal carcinoma (CRC). DS and InvSM are not always present in endoscopic bioptic samples of CRC. In our study we investigated  presence of necrosis with exudate (NE) and invasion of the colorectal mucosa (InvM) as possible additional diagnostic histologic criteria for CRC. We analysed  incidence of DS, InvSM, NE, and InvM in 448 consecutive cases of endoscopic biopsis of lesions endoscopically suspicious for CRC and evaluated  diagnostic predictability of DS, invSM, NE and InvM in routine biopsy practice. The histologic slides were stained by H&E and the Kreyberg-Jareg trichrome method. DS was found in 81.9% of lesions suspicious for CRC and in 40 cases was the only change suggesting CRC, with 2.5% false-positive result. In 38 cases, NE was the only change suggesting CRC with 7.9% false-positive result. InvSM was present in 27.4% of cases, and was always associated with other changes. InvM appeared in 22.3% of cases, most frequently in association with DS and NE. In 15 cases, InvM was the only change suggesting CRC with a 13.3% false-positive result. We conclude that the finding of NE or InvM in endoscopic specimens strongly supports the diagnosis of CRC even in the absence of DS and InvSM, and that the reliability of CRC  diagnosis correlates  with the number of histologic criteria found.
Program