Abstract: Objective To explore the clinical characteristics and regularity of tamoxifen-induced fatty liver in breast cancer patients. Methods To collect 227 cases of breast cancer patients treated with tamoxifen in our hospital from January 1st, 2011 to December 31st, 2017, of whom 78 cases had fatty liver before tamoxifen treatment, and the other 149 patients hadn't. The incidence and time to onset of fatty liver disease, liver function, body mass index (BMI), and the prognosis were analyzed for the patients without fatty liver before tamoxifen treatment. Results One hundred and thirty-one cases of new fatty liver were found after tamoxifen treatment in 149 patients, and the incidence was 87.92%. There was no statistically significant difference in the incidences between patients under 40 and those over 40(P=0.122), Among the 131 cases, 32.82% patients were diagnosed with fatty liver within 3 months, and 83.97% patients were diagnosed within 9 months. There was no statistically significant difference in the level of alanine aminotransferase (ALT) after tamoxifen treatment between the patients with newly diagnosed fatty liver and the patients without fatty liver. Among patients with newly diagnosed fatty liver, 9.16% (12/131) of the tamoxifen-induced fatty liver patients improved themselves during medication, 26.53% (13/49) disappeared after the withdrawal of tamoxifen. Statistical Results showed that the incidence of fatty liver in patients after taking tamoxifen was not related to BMI. Conclusion The incidence of fatty liver in breast cancer patients treated with tamoxifen was relatively high in our hospital, and the occurrence of fatty liver had no significant relationship with the patient's age, ALT, and BMI.

Key words: tamoxifen, fatty liver, breast cancer