Image analysis and Ki-67 expression in urothelial dysplasia and carcinoma

الملخص EN

Background/aim Cancer of the urinary bladder is a worldwide disease in which transitional cell carcinoma is the most common histologic type.

The diagnosis of dysplasia is particularly important, as it is the precursor of invasive carcinoma.

The present study aimed to investigate the role of image analysis together with Ki-67 immunostaining in bladder dysplasia and invasive urothelial carcinoma.

Materials and methods This study was carried out in 80 urinary bladder paraffin blocks that were selected from the Department of Pathology of Kasr El-Aini Hospital, Cairo University, Egypt.

The studied cases were divided into four groups: six cases of normal bladder mucosa, 12 cases of chronic cystitis, 18 cases of epithelial dysplasia, and 44 cases with transitional cell carcinoma.

Morphometric analysis and Ki-67 expression were studied in all cases using an image analysis system.

Results All morphometric parameters, DNA index, and proliferating cells’ percent and Ki-67 index were increasing from normal, chronic cystitis, dysplasia to carcinoma cases.

However, nuclear area, length, size, and epithelial stromal ratio showed significant differences between dysplasia and carcinoma cases (P<0.05).

High-grade carcinoma showed significant enlargement of nuclear area and size, as compared with low-grade carcinoma.

DNA index and proliferating cells’ % showed a significant difference between dysplasia and carcinoma cases.

Both parameters were significantly higher in high-grade carcinoma.

Normal bladder and chronic cystitis cases exhibited negative stain for Ki-67.

However, all cases of dysplasia and carcinoma exhibited a positive stain for Ki-67.

The carcinoma cases showed a significantly higher Ki-67 index (68%) than the dysplastic cases (34%).

Conclusion The present study revealed the usefulness of image analysis together with Ki-67 expression in discriminating cases of bladder dysplasia and carcinoma.