Antiproliferative and metabolic effects of metformin in a preoperative window clinical trial for endometrial cancer.

We conducted a preoperative window study of metformin in endometrial cancer (EC) patients and evaluated its antiproliferative, molecular and metabolic effects. Twenty obese women with endometrioid EC were treated with metformin (850 mg) daily for up to 4 weeks prior to surgical staging. Expression of the proliferation marker Ki-67, estrogen receptor (ER), progesterone receptor (PR), adenosine monophosphate-activated protein kinase (AMPK), and downstream targets of the mammalian target of rapamycin (mTOR) pathway were measured by immunohistochemistry. Global, untargeted metabolomics analysis of serum pre- and postmetformin treatment, and matched tumor, was performed. Metformin reduced proliferation by 11.75% (P = 0.008) based on the comparison of pre- and posttreatment endometrial tumors. A total of 65% of patients responded to metformin as defined by a decrease in Ki-67 staining in their endometrial tumors post-treatment. Metformin decreased expression of phosphorylated (p)-AMPK (P = 0.00001), p-Akt (P = 0.0002), p-S6 (51.2%, P = 0.0002), p-4E-BP-1 (P = 0.001), and ER (P = 0.0002) but not PR expression. Metabolomic profiling of serum indicated that responders versus nonresponders to treatment were more sensitive to metformin's effects on induction of lipolysis, which correlated with increased fatty acid oxidation and glycogen metabolism in matched tumors. In conclusion, metformin reduced tumor proliferation in a pre-operative window study in obese EC patients, with dramatic effects on inhibition of the mTOR pathway. Metformin induced a shift in lipid and glycogen metabolism that was more pronounced in the serum and tumors of responders versus nonresponders to treatment.This study provides support for therapeutic clinical trials of metformin in obese patients with EC.

Displaced granulosa cells in the fallopian tube mistaken for metastatic granulosa cell tumor.

A 44-yr-old woman underwent a total hysterectomy and bilateral salpingectomy secondary to uterine leiomyomas. Gross examination of the fallopian tubes revealed no masses or lesions; however, 2 small foci of granulosa cells were identified microscopically within one of the fallopian tubes. These foci were suspicious for granulosa cell tumor metastases. The patient subsequently underwent a bilateral oophorectomy, which revealed no primary granulosa cell tumor. Immunohistochemical studies were used to help support the benign nature of the granulosa cells within the fallopian tube. A review of the literature revealed only 1 similar case report of displaced benign granulosa cells within the fallopian tubes. The ovaries in both this case and the previous case report were found to contain multiple cystic follicles, suggesting ovulation as the likely mechanism of displacement. Knowledge of this rare occurrence and the use of immunohistochemical staining are paramount to making a correct diagnosis, thus preventing a misdiagnosis of malignancy and possible unnecessary treatment.