INTRODUCTION: Breast cancer is the most frequently diagnosed cancer and the leading cause of cancer-related death among women worldwide. Breast cancer bone metastasis is associated with skeletal events, including acute fractures, compression of the spinal cord, surgery and radiotherapy to the spine, as well as bone pain and hypercalcemia, resulting in decreased mobility and diminished quality of life. Greater understanding of the bone metastasis pathophysiology will highly likely to lead to the discovery of an effective treatment option. This study aims to test whether the serum bone profile and expression level of cathepsin K (CTSK) in breast carcinoma is associated with metastasis.
METHODS: In this study, 116 participants, 58 patients who had been diagnosed with breast cancer (n=22 without metastasis and n=36 with metastasis) and 58 healthy controls were included. Serum biochemical profile and immunostaining of CTSK in the breast carcinoma were investigated.
RESULTS: The mean values of calcium, 25-OH Vitamin D, ALP, albumin, phosphorus, magnesium, TSH, cholesterol, PTH and CRP (mg/L) were 11.5±2.03, 28.12±10.5, 93.3±7.9, 3.9±0.3, 3.7±1.64, 1.8±0.24, 2.5±1.5, 165.1±28.02, 63.4±18.9 and 7.7±4.9. Individual data revealed that 70% of patients without metastasis has PTH above normal while 65% has calcium and 62% patients has ALP above normal levels, which were further increased in metastasis. Low Mg levels were detected in 13/58 of the patients with breast cancer and 3/58 of the control group.13/58 of the patients with breast cancer showed low total calcium, and 32/58 of the breast cancer group showed high calcium levels.
DISCUSSION AND CONCLUSION: The present study results suggest that CTSK expressions are associated with a higher tumour stage and distant metastasis, suggesting serum bone profile and level of CTSK expression are significant parameters in the disease diagnosis and monitoring of breast cancer metastasis.