Immunohistochemical expression of topoisomerase II a and tissue inhibitor of metalloproteinases 1 in locally advanced breast carcinoma

Objectives To evaluate immunohistochemical expression of topoisomerase II a (TOP2α) and tissue inhibitor of metalloproteinases 1 (TIMP-1) in an attempt to identify their prognostic roles in locally advanced breast cancer (LABC). Background LABC is a heterogeneous clinical entity that remains a clinical challenge. Efforts are still needed to identify new markers in an attempt to predict response to therapy and prognosis. Patients and methods This study included 84 pretreatment needle core biopsies of LABC cases subjected to TOP2α and TIMP-1 immunohistochemical staining and the expression was correlated with some prognostic clinicopathlogical parameters of the patients studied. Results Fifty-seven of 84 cases (67.9%) showed positive TOP2 expression, with the proportion of TOP2α immunopositive cells (%score) ranging from 0 to 95%, mean ± SD of 27.84 ± 26.16%, and the median was 25%. Positive TOP2α expression was significantly associated with the presence of necrosis ( P = 0.03). There was also a near-significant association between positive TOP2α expression and high mitotic count ( P = 0.08). Forty-eight of 84 cases (57.1%) showed positive TIMP-1 expression with proportion of TIMP-1 immunopositive cells (%score) ranged from 0 to 95%, mean ± SD of 35.59 ± 32.93%, and the median was 30%. Positive TIMP-1 expression was significantly associated with a low apoptotic count ( P = 0.03). Conclusion TOP2α-positive expression in diagnostic samples of LABC patients is associated with poor prognostic features such as the presence of necrosis, whereas TIMP-1 is associated with a low apoptotic count.