International Journal of Clinical and Diagnostic Pathology

Methods: Descriptive study wherein 100 cases of primary ccRCC and 50 controls tissues were evaluated for CA-9 by immunohistochemistry. Immunoreactivity scores and pattern of staining were correlated with Furhman grading, clinical staging and risk stratification.

Results: 88% cases of ccRCC exhibited CA-9 immunopositivity wherein 20% nonclear cell category were positive exhibiting strong statistical correlation between CA-9 immnoexpression and ccRCC. Low grade tumours, lower stage grouping and low risk tumours (UCLA integrated clinical staging) exhibited strong to moderate positivity while high grade, high stage and high risk tumours were either negative or exhibited weak patchy positivity and association was statistically significant.

Conclusion: CA-9 is a valuable diagnostic marker for ccRCC and its expression correlates with low grade low risk tumours with favourable prognosis.