This study aimed to investigate the bicarbonate status of Chinese primary breast cancer patients with different clinicopathology and molecular subtypes. A total of 4834 primary breast cancer women and 583 women with breast benign tumors were included from the China Database for Concomitant Disease of Breast Cancer (CDCDBC). Breast cancer patients had significantly lower serum bicarbonate levels compared to women with a benign breast tumor (serum bicarbonate: 24.6±2.50 mmol/L vs 25.2±2.36 mmol/L, P<0.001; the proportion of low bicarbonate status: 25.22% vs 15.69%, P<0.001). Patients with T3/T4-stage had the highest serum bicarbonate levels (T3/T4 vs Tis: Z = -2.944, P < 0.01; T3/T4 vs T1/T2: Z = 4.610, P < 0.001). In the T2 stage, the distribution interval of serum bicarbonate levels in lymph node metastases of ≥ 3, and no lymph node metastases was statistically different (P < 0.01).  There are statistical differences in serum bicarbonate values among Luminal A, Luminal B, HER2 overexpression, and Triple-negative breast cancer (TNBC)(Z = 8.330, P = 0.040). The TNBC patients had lower serum bicarbonate levels compared to that in HER2 overexpression-type patients (serum bicarbonate: P<0.01; the proportion of low bicarbonate status: 26.74% vs 21.80%, P<0.05). The ER (+) patients had lower serum bicarbonate levels compared to the ER (-) patients (serum bicarbonate: 24.68±2.52 mmol/L vs 25.03±2.50 mmol/L, P<0.05; the proportion of low serum bicarbonate: 24.02% vs 20.96%, P <0.01), while the PR (+) patients had lower serum bicarbonate levels compared to the PR (-) patients (serum bicarbonate: 24.55±2.52 mmol/L vs 25.02±2.48 mmol/L, P<0.05; the proportion of low serum bicarbonate: 26.48% vs 19.23%, P <0.01) with T1 stages.Breast cancer patients with different clinicopathology and molecular subtypes have different bicarbonate status and those patients with higher T-stages or larger tumor lesions are more acidic.

Junhan Feng, Lingquan Kong. The bicarbonate status of the Chinese primary breast cancer patients with different clinicopathology and molecular subtypes. International Journal of Frontiers in Medicine (2024), Vol. 6, Issue 4: 51-61. https://doi.org/10.25236/IJFM.2024.060407.

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