High levels of
heparanase are detected in many types of
tumors, associated with bad prognosis. Typically,
heparanase levels are evaluated in a biopsy taken from the primary lesion, whereas its expression by the resulting
metastases is most often unresolved. This becomes critically important as anti-
heparanase compounds enter advanced clinical trials. Here, we examined the expression of
heparanase in pairs of primary and the resulting distant
metastases of
breast carcinoma. Interestingly, we found that
heparanase expression in the metastatic lesion does not always reflect its expression in the primary
tumor. Accordingly, in some cases, the primary lesion was stained positive for
heparanase while the
metastasis stained negative, and vice versa.
Heparanase discordance occurred in 38% of the patients, higher than that reported for
hormone receptors, and was associated with bad prognosis. Thus, examination of
heparanase levels in the
tumor metastases should be evaluated for most efficient
precision medicine applying
heparanase inhibitors. Furthermore, we found that in stage I
breast cancer patients strong
heparanase staining is associated with shorter overall survival. Thus,
heparanase levels can assist in the diagnosis and in determining the necessity and type of treatment in early stage
breast cancer.