Lymphatic invasion using D2-40 monoclonal antibody and its relationship to lymph node micrometastasis in pN0 gastric cancer.

The monoclonal antibody D2-40 is a specific lymphatic endothelial markers and D2-40 staining have been applicable to evaluate lymphatic invasion in various malignant neoplasms. In the present study, we investigated lymph node micrometastasis determined by immunohistochemistry (IHC) and reverse transcription-polymerase chain reaction (RT-PCR) in all dissected lymph nodes obtained from 80 patients with node-negative gastric cancer, and analysed the relationship between micrometastasis and clinicopathological findings including lymphatic invasion of the resected primary tumour using D2-40 immunohistochemical staining. The incidence of micrometastasis determined by IHC and RT-PCR was 11.3% (nine out of 80) and 31.3% (25 out of 80), respectively. Although haematoxylin-eosin (HE) staining revealed lymphatic invasion in 11.3% (nine out of 80) of patients, D2-40 staining uncovered new invasion in 23.8% (19 out of 80) of patients. In the diagnosis of HE and D2-40 staining, the incidence of micrometastasis was significantly higher in patients with lymphatic invasion than in those without lymphatic invasion (P=0.0150 and P<0.0001, respectively). Micrometastasis correlated more closely with D2-40 than with HE staining. We demonstrated a high incidence of micrometastasis and lymphatic invasion and a correlation between them even in pN0 gastric cancer. When planning less invasive treatment, the presence of such occult cancer cells should be considered.

Detection of sentinel nodes and micrometastases using radioisotope navigation and immunohistochemistry in patients with gastric cancer.

BACKGROUND: Patients with early gastric cancer may be treated by minimally invasive surgery. This study investigated the value of sentinel node (SN) navigation surgery, including detection of micrometastases, in patients with clinical (c) T1 and T2 gastric cancer. METHODS: The day before surgery (99m)Tc-radiolabelled tin colloid was injected submucosally near the tumour. After resecting the stomach, radioisotope uptake in all dissected lymph nodes was measured during and after surgery. Micrometastasis was detected immunohistochemically using an anticytokeratin antibody. RESULTS: SNs were identified in 99 of 104 patients. The rate of identification of SNs in patients with cT1 and cT2 tumours, excluding three technical failures, was 99 and 95 per cent respectively. Lymph node metastases and/or micrometastases were found in 28 patients (15 cT1 and 13 cT2). In the 15 patients with cT1 tumours, at least one SN contained metastasis and/or micrometastasis. For cT1 tumours, the sensitivity and accuracy of detecting SNs were both 100 per cent. Six patients with cT2 tumours had false-negative results. CONCLUSION: SN navigation surgery appears to be clinically useful only for cT1 tumours. Based on SN results, the extent of lymphadenectomy may be reduced in patients with early gastric cancer.

Endoscopic quadrantectomy for breast cancer with sentinel lymph node navigation via a small axillary incision.

A great deal of clinical experience has firmly established the concept of the sentinel lymph node (SN) in breast cancer. SN biopsy allows treatment without axillary lymphadenectomy and has made it possible to perform a surgical intervention via just a small skin incision. In partial resection of the breast (quadrantectomy), we use a double retractor to form a workspace under the skin via a small axillary incision. Resection does not require a large incision even in cases in which the cancer lesion is located in the upper inner or lower inner quadrant of the breast, as the endoscope allows the surgeon to see the workspace formed by the double retractors.