Drug concentrations in axillary lymph nodes after lymphatic chemotherapy on patients with breast cancer

BACKGROUND: Lymph node status is one of the decisive prognostic factors in breast cancer. Chemotherapy targeting regional lymphatic tissues has emerged as a promising therapy for the treatment of malignancies with a high tendency to disseminate lymphatically. The present study determined the drug concentrations in axillary lymph nodes after lymphatic chemotherapy (LC) in patients with breast cancer and compared the results with those receiving intravenous chemotherapy (VC) to investigate whether LC could improve the accumulation of anticancer drug in regional lymph nodes. METHODS: Sixty patients with breast carcinoma confirmed by preoperative puncture-biopsy were divided into two groups at random. The LC group (n = 30) received a subcutaneous injection of 4 ml of carboplatin-activated carbon suspension, containing 20 mg of carboplatin, adjacent to the primary tumour. The VC group (n = 30) received an intravenous administration of an equal dose of aqueous carboplatin. At 1, 12, 24, 36 and 48 hours after administration, modified radical mammectomies were performed on 12 patients at each time point, with 6 from each group. Axillary lymph nodes were removed for pathological examination. The platinum concentrations in nodes were determined by Zeeman atomic absorption spectrometry. RESULTS: A total of 275 axillary lymph nodes were resected, with 154 in the LC group and 121 in the VC group. Of the 275 lymph nodes, 136 (49.5%) from 23 patients (38.3%) had histopathologically detected metastases. At 1, 12, 24, 36 and 48 hours after injection, the carboplatin concentrations in the LC group were 11.82 ± 3.50, 23.58 ± 7.34, 18.22 ± 4.93, 16.70 ± 5.15 and 14.62 ± 4.29 μg/g (means ± SD), respectively, whereas those in the VC group were 0.06 ± 0.02, 0.11 ± 0.05, 0.10 ± 0.02, 0.05 ± 0.02 and 0 μg/g, respectively. Significant differences were found in each corresponding comparison (P < 0.001). Lymph node metastasis was uncorrelated with drug concentration (P > 0.05). CONCLUSION: LC can effectively and continuously improve the drug concentrations in axillary lymph nodes in patients with breast cancer, in comparison with VC.