Background: Apolipoprotein D is a glycoprotein of the human plasma whose functional role remains unclear. On the other hand, this protein is also produced by breast carcinomas and is positively associated with a favorable outcome of patients. However, none study has focused on metastasic lesions.
Aim: To analyze apolipoprotein D expression in breast cancer patients and their synchronous metastasic axillary lymph nodes.
Methods: We analyzed by immunohistochemical assay both, the tumoral expression of apolipoprotein D in primary tumors and in their synchronous metastasic axillary lymph nodes of 30 node-positive breast cancer patients.
Results: Of the primary tumors, 28 (93.3%) showed a positive immunostaining for apolipoprotein D, although there was wide variability immunostaining values. On the other hand, 16 (53.3%) patients showed a positive immunostaining for the protein in their tumoral lymph nodes. In addition, there was a significant positive relationship between the tumoral expression of apolipoprotein D in primary tumors and metastasic lymph nodes (P < 0.05). However, only immunostaining values of the protein in primary tumors achieve statistical signification (P < 0.05) as prognostic factor of favorable evolution to predict overall survival from patients.
Conclusions: Apolipoprotein D is also expressed in metastasic lymph nodes of breast carcinomas, but with a different pattern of immunostaining and less clinical significance than in primary tumors.