Efficacy of metformin in the treatment of estrogen-dependent endometrial carcinoma complicated with type 2 diabetes mellitus and analysis of its prognosis.

PURPOSE

To explore the efficacy of metformin in the treatment of estrogen-dependent endometrial carcinoma (EC) complicated with type 2 diabetes mellitus (T2DM), and the influencing factors for the prognosis of such patients.

METHODS

The clinical data of 68 patients histopathologically diagnosed with estrogen-dependent EC complicated with T2DM in our hospital from April 2013 to March 2016, and 132 estrogen-dependent EC patients with normal blood glucose during the same period were retrospectively analyzed. The clinical and pathological features were compared between diabetic patients and non-diabetic patients. The diabetic patients were divided into the metformin group and the non-metformin group according to whether metformin was taken. The survival curves were plotted and analyzed using the Kaplan-Meier method, and the overall survival (OS) and progression-free survival (PFS) were compared among the three groups. Moreover, the multivariate analysis was performed using the COX regression model, so as to analyze the influencing factors for the prognosis of patients with estrogen-dependent EC complicated with T2DM.

RESULTS

Compared with non-diabetic patients, diabetic patients had higher age of onset, a higher BMI, higher proneness to hypertension, more advanced tumor stage, a higher histological grade, deeper myometrial invasion and a higher risk of lymph node metastasis. Both OS and PFS of T2DM patients who took metformin were significantly prolonged compared with those of T2DM patients who did not take metformin (p=0.021, p=0.011). There were no statistically significant differences in the PFS and OS between diabetic patients who took metformin and non-diabetic patients (p>0.05). According to the results of Cox multivariate analysis, OS was obviously shortened in case of high age of onset, complicated T2DM, late pathological stage of tumor advanced tumor stage, high histological grade, deep myometrial invasion and positive lymph node metastasis, while PFS could was obviously shortened in case of complicated T2DM, late pathological stage of tumor advanced tumor stage, high histological grade, deep myometrial invasion and positive lymph node metastasis. Metformin evidently improved OS and PFS.

CONCLUSION

Complicated T2DM, high age of onset, advanced tumor stage, high histological grade, deep myometrial invasion and positive lymph node metastasis are factors for the poor prognosis of patients with estrogen-dependent EC, and metformin can significantly ameliorate both OS and PFS in these patients, thereby improving their prognosis.