The aim of this study is to evaluate the usefulness of diffusion-weighted (DW) magnetic resonance (MR) imaging in detecting peritoneal dissemination in cases of gynecological malignancy. We retrospectively analyzed MR images obtained from 26 consecutive patients with gynecological malignancy. Peritoneal dissemination was histologically diagnosed in 15 of the 26 patients after surgery. We obtained DW images and half-Fourier single-shot turbo-spin-echo images in the abdomen and pelvis, and then generated fusion images. Coronal maximum-intensity-projection images were reconstructed from the axial source images. Reader interpretations were compared with the laparotomy findings in the surgical records. Receiver-operating characteristic (ROC) curves were used to represent the presence of peritoneal dissemination. In addition, the sensitivity and specificity were calculated. DW imaging depicted the tumors in 14 of 15 patients with peritoneal dissemination as abnormal signal intensity. ROC analysis yielded Az values of 0.974 and 0.932 for the two reviewers. The mean sensitivity and specificity were 90 and 95.5%. DW imaging plays an important role in the diagnosis and therapeutic management of patients with gynecological malignancy.

To clarify whether and how PTEN and the phosphatidylinositol 3-kinase/Akt pathway relates to endometrial cancer we examined the expression of these pathway-related proteins in patients with endometrial cancer. Of 103 endometrial cancers, 37 (36%) showed negative immunohistochemical staining for PTEN. Western blotting revealed that the level of phosphorylated Akt expression in PTEN-negative cases was significantly higher compared with that in positive cases. We found a significant inverse correlation between PTEN and phosphorylated Akt. The present study indicates the phosphorylation of Akt accompanied by the loss of PTEN in clinical specimens of endometrial cancers.In order to investigate the relationship between PTEN expression and prognosis in endometrial cancer, 98 patients with advanced endometrial cancer were newly enrolled. The survival rate for PTEN-positive patients was significantly higher than that for PTEN-negative or -heterogeneous staining patients. Of the 98 patients, 25 underwent radiation therapy, 62 received chemotherapy after surgery, and the remaining 11 did not have any postoperative treatment. When patients underwent chemotherapy, the survival rate for PTEN-positive cases was clearly higher than that for PTEN-negative or -heterogeneous cases (62.4 vs 11.8%). Subsequent multivariate analysis revealed that PTEN staining was an independent prognostic factor for patients undergoing chemotherapy. The current study demonstrates that PTEN-positive staining is a significant prognostic indicator of favorable survival for patients with advanced endometrial cancer who undergo postoperative chemotherapy.

Recent studies demonstrated that a single guanine insertion polymorphism in a matrix metalloprotease‐1 promoter created an Ets binding site and affected the elevation of the transcriptional level of matrix metalloproteinase‐1 (MMP‐1). Furthermore, in tumor cell lines derived from melanoma and breast cancer, the incidence of the 2G/2G genotype was significantly higher than that in the normal population. To evaluate the contribution of this polymorphism in endometrial carcinomas, we genotyped 100 endometrial carcinomas and then analyzed immunoexpression of MMP‐1 in these carcinomas. We found that endometrial carcinoma patients showed a significantly higher rate of 1G/2G or 2G/2G genotype than control individuals, and that tumors containing the 2G allele(a) expressed MMP‐1 protein more frequently than those with 1G/1G genotype. Therefore, the single nucleotide polymorphism at the MMP‐1 promoter affected the expression level of the MMP‐1 protein, which may result in the association with more aggressive character in endometrial carcinoma. Our result suggests that the presence of 2G polymorphism at the MMP‐1 promoter may be one of the risk factors for the development and/or progression of endometrial carcinoma.

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Resistance of clear cell carcinoma (CCC) of the ovary to platinum-based chemotherapy is associated with a poor prognosis. However, the mechanism underlying the resistance of CCC to platinum has not yet been understood. We conducted the present study to clarify the mechanism of cisplatin (CDDP) resistance in CCC cells. Eleven CCC and 5 serous adenocarcinoma (SAC) cell lines were used in this study. The IC₅₀ to CDDP ranged from 1.3 to 18.0 µM for CCC cells and from 2.2 to 13.0 µM for SAC cells. There was no correlation between multidrug resistance-associated protein expression and the sensitivity to CDDP in CCC cells. In contrast, the doubling time for CCC cells was significantly longer than that for SAC cells (61.4 vs. 29.8 h). A significant reverse correlation between the S-phase fraction and the response to CDDP was observed (r = 0.647, p < 0.05). The present study suggests that the resistance of CCC to CDDP may be caused by low cell proliferation.