Biomedical subjects

Nobuhiro Imanaka

Publications and source records attributed to Nobuhiro Imanaka.

2 recordsLinked to original sources

PubMed2002

Dynamic-enhanced MRI predicts metastatic potential of invasive ductal breast cancer.

BACKGROUND: Dynamic magnetic resonance imaging (MRI) has improved the detection of breast malignancies. The method is based on estimating the velocity of contrast enhancement taking into account increased angiogenesis in tumor. Microvessel density correlates with breast carcinoma metastasis. Thus, we hypothesized that contrast enhancement on MRI correlates with metastasis in breast cancer patients. The present study attempts to clarify the quantitative assessment of dynamic data, and examines the correlation between MRI enhancement and breast carcinoma metastasis. METHODS: The subjects consisted of 31 patients with invasive ductal breast cancer. Twenty patients were disease free for five years (group A), and eleven patients suffered from metastatic disease at distant sites concurrently or postoperatively (group B). Dynamic MRI was performed preoperatively using a 1.5T system in all cases. Using the dynamic data, the signal intensity (SI)ratio and SI index were determined and analyzed retrospectively taking into account the presence of distant metastases. RESULTS: The values of the SI ratio were 2.2+/-0.7 in group A and 2.3+/-0.4 in group B, respectively, with no significant difference seen between the groups. The SI index value was significantly higher in group B (28.5+/-32.8) than in group A (10.3+/-5.5, p<0.05). CONCLUSIONS: The current series suggests that the SI index could distinguish patients with high risk of distant metastasis from disease free patients, preoperatively. If a suitable borderline value were established, the quantitative dynamic parameter determined by MRI may be useful for predicting the prognosis of breast cancer patients.

Adult↗

PubMed2002

Will subareolar injection be a standard technique for sentinel lymph node biopsy?

BACKGROUND: Controversy surrounds the correct injection site of radioisotope (RI) and blue dye for sentinel node biopsy (SNB) in breast cancer, and there have been some reports on the advantages of subareolar (SA) injection. We carried out a study to assess whether SA injection is useful for all patients undergoing SNB. METHODS: In this prospective study, 20 patients with T1 or T2 tumors clinically node negative, were enrolled. Injection of 99mTc-phytate (0.5 mCi) was performed two times (3 to 5 days before surgery and the day of surgery) for each patient. The first RI injection was SA, and the second RI injection was subdermal (SD). The location and number of hot nodes were assessed by lymphoscintigraphy (LSG) and hand-held gamma probe. RESULTS: There were no patients in whom hot nodes on LSG were visualized in clearly different locations between the SA and SD injection sites. However, there were 2 patients in whom hot nodes were identified at different locations with a gamma probe. Seven patients had more hot nodes on LSG with SD injection than SA injection. Eight patients had a higher RI count of hot nodes by SD injection than SA injection. The mean RI count of hot nodes by SA injection was higher than that after SD injection. CONCLUSION: SA and SD lymphatic flow run into the same node in most patients, however, SD injection is more useful than SA injection in some patients. Though SA injection is a useful technique, it may not identify sentinel lymph nodes correctly in patients with multiple lesions or tumors in the upper outer quadrant.

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