Evaluation of Ki-67 and p53 expression in primary and repeated liver metastases of GISTs.

There has been little research evaluating changes related to tumor cell proliferation between primary and metastatic tumors of gastrointestinal tumors in the same case. We herein report the case of a 50-year-old woman with a gastric gastrointestinal stromal tumor (GIST), who developed metastatic liver tumors three times in the 7 years after proximal gastrectomy for GIST. The primary and all the metastatic liver tumors, except the second, showed fascicular/storiform architecture and the short spindle cell type. The diffuse epithelioid cell proliferation was observed in the second metastatic liver tumor. Although the immunostaining pattern with respect to GIST differentiation markers had been preserved in the primary tumor as well as in all of the metastatic tumors, the latter showed weaker positivity of both Ki-67 and p53 than the primary GIST. The primary tumor showed diffuse positive p53, and the highest value of Ki-67 labeling index (LI) among them. The metastatic liver tumors showed focal, negative or sporadic positive appearances of p53, however, Ki-67 LI were scattering among them. Immunohistochemical assessment of Ki-67 LI and p53 might be useful for evaluating changes related to tumor cell proliferation between primary and metastatic tumors of GISTs.

High en bloc resection rate achieved by endoscopic mucosal resection with IT knife for early gastric cancer.

BACKGROUND/AIMS: Circumferential endoscopic mucosal resection (EMR) around lesions performed by an insulation-tipped diathermic knife (IT knife) increases en bloc resection rates, suggesting the possibility of expanding indications for EMR. METHODOLOGY: Clinical outcome of EMR performed by IT knife under general anesthesia was evaluated for 26 patients with 29 early gastric cancer. RESULTS: Successful en bloc resection rates obtained by the IT knife were 100, 87.5, 90.0 and 100% for lesions < or =10 mm in size, 11-20 mm, 21-30 mm, and > or =31 mm, respectively. They were significantly higher with the IT knife than those obtained by the conventional method (IT knife method: 93.1% vs. conventional method: 28.5%, p<0.0001). Two lesions were lateral margin positive, and in three cases invasion of lesions was observed as deep as the submucosa. Distal, total, and proximal gastrectomy with D2 lymphadenectomy, respectively, was provided in 3 cases; however, no lymph node involvement was found in any of the resected specimens. Bleeding and perforation were observed in 3 cases, respectively, however, no additional surgical treatment was required for these patients. CONCLUSIONS: EMR by means of the IT knife under general anesthesia can be performed safely and adequately. It is a useful treatment modality for early gastric cancer.

Pharmacokinetic analysis of ductal carcinoma in situ of the breast using dynamic MR mammography.

The purpose of this study was to assess the relationship between functional parameters derived from dynamic MR imaging and the histological findings of breast ductal carcinoma in situ (DCIS) and DCIS with invasive foci, and to evaluate whether these parameters might predict DCIS patient outcome. Two parameters, amplitude A and k(21), were determined from multicompartmental pharmacokinetic analyses of dynamic MR mammography in 39 patients with needle biopsy-proven primary DCIS. After surgery, the histological tumor characteristics, including microvessel density (MVD) (anti-CD-34), vascular permeability (anti-VEGF antigen) and histological grade, were evaluated. Histology revealed 27 pure DCIS and 12 DCIS with invasive foci. In pure DCIS, positive correlations between MVD and amplitude A (r=0.56, P<0.0025) and between MVD and k(21) (r=0.43, P=0.02) were found. As for histological grade, the differences in both functional parameters of grade 1 versus grade 2 and grade 1 versus grades 2 and 3 combined were significant (P<0.05). No significance was found in the analysis of DCIS with invasive foci. Our results indicated that functional MRI-based parameters might possess the potential to predict the outcome of patients with DCIS. Further study will be needed with larger series over longer periods.

Detection of sentinel lymph nodes in gastric cancers based on immunohistochemical analysis of micrometastases.

BACKGROUND AND OBJECTIVES: The sentinel lymph node (SN) theory has the potential to change the trend of surgery for gastric cancer that is based on wide resection of the stomach with dissection of regional lymph nodes. However, feasibility tests of SN mapping procedures in gastric cancers with analysis of micrometastasis are rare. This study aimed to estimate the clinical usefulness of SN mapping using a dual procedure with dye- and gamma probe-guided techniques for gastric cancers, based on immunohistochemical staining (IHC) analysis. METHODS: SN mapping procedures were performed on 41 patients with T1-T2 gastric cancer, and gastrectomy with D2 lymphadenectomy followed. All SNs and non-SNs obtained from the patients were tested by IHC analysis using anti-cytokeratin antibodies. RESULTS: Using the dual mapping procedure, SNs were detected in all patients (100%). SN was positive in all patients with lymph node metastasis except in one with non-solid type poorly differentiated adenocarcinoma with marked lymphatic permeation, thus achieving an accuracy rate of 98%. CONCLUSIONS: The method was accurate in predicting nodal status and could be an indicator for less invasive treatment in patients with gastric cancer.