Tadaki Nakahara

Validation study of radio-guided sentinel lymph node navigation in esophageal cancer.

Background:Radio-guided detection of sentinel lymph nodes (SLN) has been used to predict regional lymph node metastasis in patients with melanoma and breast cancer. However, the validity of the SLN hypothesis is still controversial for esophageal cancer. The aim of this study is to evaluate the feasibility and accuracy of radio-guided SLN mapping for esophageal cancer. Methods:Seventy-five consecutive patients who were diagnosed preoperatively with T1N0M0 or T2N0M0 primary esophageal cancer were enrolled. Endoscopic injection of technetium-99m tin colloid was performed before surgery and radioactive SLNs were identified with preoperative lymphoscintigraphy and gamma probe. Standard radical esophagectomy with lymphadenectomy was performed in all patients and all resected nodes were evaluated by routine pathologic examination. Results:SLNs were identified successfully in 71 (95%) of 75 patients. The mean number of identified SLNs per case was 4.7. Twenty-nine (88%) of 33 cases with lymph node metastasis showed positive SLNs. The diagnostic accuracy based on SLN status was 94% (67/71). Distribution of identified SLNs was widely spread from the cervical to abdominal areas. Conclusions:This study reveals that radio-guided SLN mapping is an accurate diagnostic procedure for detecting lymph node metastasis in patients with early-stage esophageal cancer.

F-18 FDG uptake in endometrial cancer.

Endometrial cancer, which is one of the most common malignant gynecologic diseases, was detected by F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) in a 60-year-old woman with abdominal distention. FDG PET revealed heterogeneous and marked accumulation in the endometrium, which was thought to represent endometrial cancer. In addition, focal intense accumulation of FDG in both lungs suggestive of lung metastases were noted. Endometrial cancer and lung metastases were confirmed by endometrial biopsy and computed tomography of the chest, respectively.

Sentinel node navigation in early stage gastric cancer--updated data and current status.

cies �2��� Until the �eginning of the 21st century, the application of the SN concept for upper ��� cancer was not fully accepted �ecause of the multi-directional and complicated lymphatic flow from the �p� u per ��� tract and relatively high incidence of anatomical skip metastases�� With gastric cancer, these clinical o�servations supported the continued relevance of D2 lymph node dissection, even for clinically negative node cases�� Now we are challenging to change this uniform strategy for early gastric cancer �ased on SN concept�� ��n the present article, current status of sentinel node navigation for early stage gastric cancer will �e introduced with up-dated data��

Molecular Detection of Sentinel Node Micrometastases in Patients with Clinical N0 Gastric Carcinoma with Real-time Multiplex Reverse Transcription-Polymerase Chain Reaction Assay

PurposeDescribed is a novel real-time multiplex reverse transcription-polymerase chain reaction (RT-PCR) assay suitable for intraoperative detection of micrometastasis (MM) in sentinel nodes (SNs) dissected from patients with clinical N0 (cN0) gastric carcinoma.MethodsOne hundred three patients with gastric cancer, who were preoperatively diagnosed with cN0 and clinical T1 or T2, were enrolled. The patients underwent SN mapping followed by standard radical gastrectomy with lymph node dissection. In addition to all SNs, non-SNs (NSNs) within the SN lymphatic basin and NSN from a different lymphatic basin were randomly sampled. All SNs and NSNs were examined by routine histologic diagnosis and RT-PCR for the expression of cytokeratin (CK) 19, CK20, and carcinoembryonic antigen (CEA).ResultsThe RT-PCR assay and histologic examination were performed in 512 SNs and 299 NSNs from 103 patients. Pathologic l lymph node metastasis was revealed in 13 (12.6%) of 103 patients. All metastatic lymph nodes were identified within SNs. SNs of these 13 patients had positive findings on RT-PCR. Twenty-eight (27.2%) of 103 patients had negative histopathology but positive findings on RT-PCR. In 7 patients (6.8%), SNs were negative but NSNs were positive on RT-PCR. RT-PCR-positive NSNs were present in the same station as corresponding SNs in 3 of these 7 patients and in the same basin as SNs in 4 patients.ConclusionsThe real-time multiplex RT-PCR assay is a useful tool for the detection of MM in SNs and NSNs in patients with gastric cancer.

FDG accumulation in aortic walls.

A 65-year-old woman with no symptoms underwent whole-body F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) for cancer screening. FDG accumulation was detected incidentally in her arterial walls, including the aortic wall. She had no history of inflammatory or cardiovascular disease. Although accumulation of FDG is well recognized in the aortic wall when vasculitis is present, this patient showed no symptoms of active vasculitis during the 22-month follow-up period after the PET study. The aortic wall might be a site where FDG accumulates physiologically in elderly persons.

Outlining the body contours with scattered photons in lymphoscintigraphy for sentinel nodes

Although lymphoscintigraphy is a useful method of detecting the sentinel nodes of malignancy, conventional lymphoscintigraphy images only the sentinel nodes without revealing their anatomical location. We, therefore, used scattered photons to attempt to outline the body contours of patients with either breast or esophageal cancer. Lymphoscintigraphy was performed 3 to 4 hours after the injection of 111 MBq of99mTc tin colloid into the peritumoral region. Images were obtained with dual-energy windows of 130 to 150 keV for the primary photons and 70 to 110 keV for the scattered photons. The images constructed from the scattered photons clearly showed the contours of the body, and the fusion images constructed from the primary and scattered photons allowed for easy identification of the location of the sentinel nodes. The results of this study confirm that images obtained from scattered photons on lymphoscintigraphy are helpful in identifying the anatomical location of sentinel nodes.

Predictors to assess non-sentinel lymph node status in breast cancer patients with sentinel lymph node metastasis

Abstract:  The next step of sentinel lymph node biopsy (SLNB) in breast cancer is to determine which patients need axillary lymph node dissection (ALND) following a positive SLNB. A prospective database of 239 patients who underwent SLNB followed by complete ALND at Keio University Hospital from January 2001 to June 2005 was reviewed. A total of 131 patients with one or more positive sentinel lymph nodes (SLNs) were further analyzed. A univariate analysis showed a significant correlation between non‐SLN involvement and lymphatic invasion, vascular invasion, number of tumor‐involved SLNs, radioactivity of SLNs, and size of SLN metastasis (p = 0.0002, p = 0.004, p = 0.006, p = 0.04, p = 0.03, respectively). By multivariate analysis, lymphatic invasion and the number of tumor‐involved SLNs remained significant predictors of non‐SLN involvement. In breast cancer patients with a positive SLN, lymphatic invasion and the number of tumor‐involved SLNs were both independent predictors of non‐SLN involvement.

Utility of quantitative 99mTc-phytate scintigraphy to diagnose early-stage non-alcoholic steatohepatitis

Objective. In patients with non-alcoholic fatty liver disease (NAFLD), liver biopsy remains the only reliable method to differentiate simple steatosis from non-alcoholic steatohepatitis (NASH). The objective of this study was to evaluate the efficacy of non-invasive 99mTc-phytate scintigraphy in the diagnosis of NASH. Material and methods. Thirty-seven patients with suspected NAFLD at the time of liver biopsy also underwent 99mTc-phytate scintigraphy. Signal intensities of regions of interest (ROI) in the liver, spleen, and heart were measured. We also examined scintigraphic features in a nutritional model of NASH in rats fed a methionine- and choline-deficient (MCD) diet. Results. The liver/spleen uptake ratio determined by scintigraphy was significantly decreased in patients with NASH in comparison with patients with simple steatosis. The liver/spleen ratio was an independent predictor distinguishing NASH from simple steatosis. The decrease was observed for all stages of NASH, including the early stage (stages 1 and 0). In animal studies, the liver/spleen uptake ratio was significantly decreased in rats after 8 weeks of MCD dietary feeding in comparison with control diet-fed rats. Conclusions. The non-invasive 99mTc-phytate scintigraphy test is a reliable tool to differentiate NASH from simple steatosis.

The importance of para-aortic lymph nodes in sentinel lymph node mapping for endometrial cancer by using hysteroscopic radio-isotope tracer injection combined with subserosal dye injection: Prospective study

OBJECTIVE The objective of this study is to evaluate the detection rate and diagnostic accuracy of sentinel lymph node (SN) mapping using hysteroscopic sub-endometrial injection of 99m-Technetium labeled phytate (Radio-isotope; RI method) and subserosal Indocyanine green (ICG) injection (Dye method) in patients with endometrial cancer. METHODS From April 2009 to December 2012, prospective evaluation of 57 Japanese endometrial cancer patients undergoing SN mapping using RI method combined with Dye method was done. To combine RI method or no was determined by a status of RI supply of the tracer injection day. As for 32 cases, both (RI+Dye) methods were used and 23 cases were performed only in Dye method. The primary endpoint was estimation of sensitivity and negative predictive value (NPV) of SN, and analysis of the distribution of SNs with metastasis. RESULTS At least one SN was detected in 100% and average number of detected SNs was 6.0 in RI+Dye method. Sensitivity and NPV were 100%, 100%, respectively. From results of SN mapping, 62.8% of SNs were present in pelvic and 37.1% in para-aortic lymph nodes (PAN). Total 56.3% of lymph nodes with metastasis were present in pelvic and 43.8% in PAN, and the distribution has no difference with SN mapping results (P=0.602). Among 13 cases with metastatic SNs, 76.9% cases showed metastasis in PAN. CONCLUSIONS This SN mapping procedure for endometrial cancer patients revealed high detection rate, sensitivity, NPV, and also indicated the importance of the SN exploration in PAN area.

Dose-related fluorodeoxyglucose uptake in acute radiation-induced hepatitis

Therapeutic assessment with fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) is sometimes problematic after radiation therapy. Herein we describe a patient with acute radiation-induced hepatitis in which PET showed dose-dependent FDG uptake. A 50-year-old man underwent FDG PET for staging of esophageal cancer. Chemoradiotherapy was delivered concurrently with a radiation field that expanded from the esophagus into the upper stomach to cover metastasis of the gastric wall. The patient also underwent FDG PET 26 days and 4 months after chemoradiotherapy to evaluate the therapeutic effect. Twenty-eight days after chemoradiotherapy, hematochemistry revealed elevated hepatic enzymes and postcontrast computed tomography showed band-like hypoattenuation in the liver with parenchymal swelling corresponding to the radiation field. FDG PET performed 26 days after chemoradiotherapy showed a wedge-shaped hypermetabolic area in which the degree of FDG uptake correlated with the prescribed radiation dose. Follow-up PET 4 months after therapy showed no abnormal uptake in the liver. Acute radiation-induced hepatitis can be a potential cause of false-positve findings of malignancy on FDG PET scans, and PET images should carefully be compared with the distribution of prescribed dose. Threshold dose might be higher for metabolic changes than for morphologic changes.