Solid tumor resection by use of a highly sensitive micromagnetic needle detection system.

The objective of this study was to evaluate the efficiency of tumor detection in parenchymal organs and their resection by use of a micromagnetic needle detection system (MNDS). A micromagnetic needle (maximum magnetic flux density = 120 mT) and a micromagnetic needle-setting device were used. An in vitro laboratory study with a gumball within gelatin representing a tumor was conducted to calculate detection rates and to measure the time required for resection by MNDS. An animal study with the cervical lymph nodes of pigs representing tumors was conducted to measure the time required for lymph node resection. The removal rate of the target lymph node was 100% with MNDS. Results show that MNDS may be useful for tumor resection in the presence of air and for the resection of tumors that are difficult to detect by ultrasonography.

Metastasis-related factors expressed in pT1 pN0 breast cancer: assessment of recurrence risk.

OBJECTIVES: Previous reports have indicated that small breast cancers without lymph node metastasis present a favorable prognosis. However, 10-20% of patients with T1 N0 invasive ductal carcinoma experience recurrence and have a poor prognosis. The objective of this study was to examine whether certain metastasis-related factors are prognostic of cancer recurrence in such patients at risk for relapse. METHODS: Nineteen patients with the carcinoma who had recurrence 1-15 years after margin-free resection were examined. The control group consisted of 20 patients with pT1 pN0 invasive ductal carcinoma who had no recurrence for > or =10 years after radical surgery. The two groups were compared with respect to clinical profiles, conventional neoplastic features, and immunohistochemical expressions of 16 metastasis-related factors. RESULTS: No significant difference was found between the two groups in clinical profiles and conventional neoplastic features. However, six factors (MMP-2, MT1-MMP, T1MP-2, VEGF, cMET, and PCNA) were significantly expressed in the recurrence group against the control group. MMP-9 was significantly less expressed in the recurrence group. Of these factors, MMP-2, MT1-MMP, and VEGF showed the highest adjusted odds ratios. CONCLUSION: MMP family and growth factors may be promising predictors of recurrence risk of early stage breast cancer.

Study of the automated breast tumor extraction using 3D ultrasound imaging: The usefulness of depth-width ratio and surface-volume index.

We applied quantitative parameters in three-dimensional ultrasonic images to distinguish benign from malignant breast tumors in 29 benign cases including 8 cysts and 21 fibroadenomas, and 32 malignant cases including 23 ductal carcinomas, 2 special types of carcinoma, 1 malignant lymphoma and 6 others. This procedure involved simultaneously acquiring video data from real-time ultrasonic images and recording the original position and orientation of the probe. Both sets of data were fed directly into a desktop computer. Fuzzy reasoning and relaxation techniques were use to automatedly extract the shape of the tumor and render it in three dimensions. We then evaluated three parameters: 2D-D/W, the so-called depth-width ratio measured in B-mode images: 3D-D/W; and the S/V index ([surface area](3)/36π [volume](2)) calculated from the three-dimensional volume extracted with this system. All three parameters were significantly higher in the malignant group (averages: 0.81, 0.64, and 11.3, respectively) than in the benign group (averages: 0.62, 0.47, and 3.78, respectively). All three parameters were thus found to be useful in differentiating the two groups.

Effects of anastrozole on lipid metabolism compared with tamoxifen in rats.

BACKGROUND: Anastrozole, a new aromatase inhibitor, has been used to treat postmenopausal metastatic breast cancer, and several clinical trials of adjuvant treatment using this agent are ongoing. However, the effects of anastrozole on lipid metabolism are unknown. The aim of this study was to evaluate the effect of anastrozole on lipid metabolism, especially lipoprotein lipase (LPL) activity, compared with tamoxifen in rats. METHODS: Ovariectomized female rats were divided into six groups: C, controls; T, tamoxifen treatment; A, anastrozole treatment; CAT, combined anastrozole/tamoxifen treatment; NAT, no treatment after tamoxifen; and AAT, anastrozole treatment after tamoxifen. The agents were orally administered for 3 weeks. Serum total cholesterol, triglycerides, and LPL activity in postheparin plasma were measured at the end of the experiment. RESULTS: Serum cholesterol levels were significantly lower in the T and CAT groups than in controls (P < 0.001). Serum triglyceride levels were significantly higher in the T group than in the other groups (P < 0.001). LPL activity was significantly lower in T and AAT groups (P < 0.01). There was no significant difference in any parameters in group A. CONCLUSIONS: Anastrozole does not affect lipid metabolism including LPL activity. There was little effect on lipid profiles during combination treatment or following treatment with tamoxifen. In a clinical setting, therefore, anastrozole might be safe for patients with abnormal triglyceride profiles during tamoxifen treatment.

New method of sentinel node identification with ultrasonography using albumin as contrast agent: a study in pigs.

The purpose of our study was to verify in animals the possibility of using albumin-enhanced ultrasonography as a modality for sentinel node detection. The nine pigs were injected subcutaneously in the neck with albumin, five with 5% solution and four with 25% solution, and then the regional lymph nodes were observed over time. It was found that, where the 5% solution had been injected, the lymph nodes showed no change, but where the 25% solution had been used, a high echo 1 to 5 mm in size was seen at the hilus of the nearest lymph node. Examination of the excised pathologic specimens of lymph nodes demonstrated that this echo was due to albumin accumulated in the efferent lymphatics. This finding suggested that this technique of ultrasonography using albumin as a contrast agent was an effective new method of identifying sentinel nodes.

Anticarcinogenic effects of isoflavones may be mediated by genistein in mouse mammary tumor virus-induced breast cancer.

Isoflavones are known to exert anticancer effects. These effects were examined using two isoflavones, biochanin A and daidzein, in a mouse mammary tumor virus (MMTV)-induced spontaneous breast cancer model. Emphasis was placed on isoflavone metabolism by the intestinal microflora and changes in estrogen levels. Germ-free (Gf) mice and their conventionalized (Cv) counterparts were assigned to three diet groups: (1) control diet, (2) biochanin A and (3) daidzein. In all groups, urine was collected from virgin female mice to analyze isoflavone metabolism by high performance liquid chromatography. These studies revealed changes of biochanin A into genistein, and of daidzein into equol, which were accelerated in the Cv animals. However, the Gf mice could not transform biochanin A into genistein, or daidzein into equol. Estrogen levels in the control and daidzein diet groups were lower in the Gf mice than in the Cv mice. The biochanin A group showed no differences in estrogen levels between the Cv and Gf animals. Four-week-old male and female animals were paired in the Gf and Cv groups. The female animals delivered and lactated repeatedly and were observed for the development of mammary cancer by palpation, twice weekly, until 15 months of age. The Cv mice showed a significantly lower incidence of breast cancer in the biochanin A diet group than in the control or daidzein groups (p < 0.05). These results suggest that the anticarcinogenic effects in this system might be produced not by daidzein or equol, but by biochanin A and/or genistein. In the Gf animals, the incidence of breast cancer was significantly higher in the biochanin A group than in the control group (p < 0.05), probably due to the increased level of estradiol in the former group. The biochanin A group tended to have a higher incidence of breast cancer than the daidzein group in the Gf group, although no significant differences were noted. Thus, no anticarcinogenic effect was produced by biochanin A alone in the Gf mice. In view of the results presented, genistein derived from biochanin A following metabolic processes in the intestinal microflora most likely acts as an inhibitor in breast carcinogenesis; biochanin A is most likely a precursor of genistein.