[123I]-IMP single-photon emission computed tomography imaging in visual snow syndrome: A case series.

BACKGROUND: Visual snow syndrome (VSS) is a neurological condition characterized by persistent flickering dots in the visual fields, palinopsia, enhanced entoptic phenomenon, photophobia, and nyctalopia. Neuroimaging evidence supports the role of the visual association cortex in visual snow syndrome.Case series: We provided clinical care to three patients with visual snow syndrome, in whom [123I]-IMP single-photon emission computed tomography (SPECT) imaging was performed. Case 1 was a 21-year-old male with a past history of migraine with aura who exhibited visual snow and entoptic phenomenon. In this patient, [123I]-IMP SPECT imaging revealed right occipital and temporal hypoperfusion with a distribution matching the ventral visual stream. [123I]-IMP SPECT imaging detected only mild bilateral frontal hypoperfusion in Case 2 and no overt abnormalities in Case 3. CONCLUSION: Although visual snow syndrome seems to be a heterogenous condition, our observations indicate that abnormal visual processing within the ventral visual stream may play a role in the pathogenesis of this condition.

Utility of the one-step nucleic acid amplification assay in sentinel node mapping for early gastric cancer patients.

BACKGROUND: To safely perform minimized gastrectomy based on sentinel node (SN) concept for early gastric cancer patients, intraoperative diagnostic accuracy is indispensable. This study aimed to evaluate the clinical utility of the one-step nucleic acid amplification (OSNA) assay in the intraoperative diagnosis of SN metastasis in early gastric cancer patients compared with that of histopathological examination. METHODS: We conducted a prospective study using the OSNA assay for 43 patients with cT1N0M0 gastric cancer undergoing gastrectomy with SN mapping. All the SNs and selected non-SNs were examined by routine histopathological diagnosis, and the OSNA assay. RESULTS: We performed permanent histopathology (PH) in 1732 lymph nodes (LNs) (286 SNs and 1446 non-SNs) obtained from 43 patients. We also evaluated 439 LNs (286 SNs and 153 non-SNs) with the OSNA assay in addition to PH. Intraoperative histopathology (IH) was performed in 214 LNs (213 SNs and 1 non-SN). PH revealed LN metastasis in 6 patients (14%), all of whom showed positive SNs by PH. The diagnostic accuracy to predict the LN status based on the SN concept by histological examination was 100%. The concordance rate between the OSNA assay and the PH and IH were 0.970 and 0.981 respectively. Discordant results between PH and OSNA assay were observed in 13 LNs. The sensitivity and specificity of the OSNA assay compared with those of PH were 0.636, and 0.988, and compared with those of IH were 0.800, and 0.995. CONCLUSION: Our results suggest that the OSNA assay is a useful and convenient tool for the intraoperative detection of SN metastasis in early gastric cancer patients.

Assessment of lymphatic flow based on the sentinel node concept in early gastric adenocarcinoma that satisfies expanded endoscopic resection criteria.

BACKGROUND: Even though indications for endoscopic resection (ER) in early gastric cancer are determined based on the potential risk of lymph node metastasis, the criteria for ER remain controversial. Sentinel node (SN) mapping for early gastric cancer can help determine regional lymphatic flow patterns. The aim of this study was to assess lymphatic flow according to the SN concept in patients with early gastric cancer, especially those who satisfy the expanded criteria for ER. METHODS: We retrospectively enrolled 301 patients diagnosed with pT1 adenocarcinoma who had undergone gastrectomy with SN mapping and had no lymphovascular invasion. Patients were categorized into six groups based on oncological assessment. We analyzed lymphatic flow, including the number of identified SN and SN basin, and the rate of SN metastasis in each group. RESULTS: Of the 301 patients, 128 (42.5%) met the criteria for ER, with 18 in the absolute group and 110 in the expanded group; 173 (57.5%) were assigned to the surgical group. SN metastasis rate tended to be higher in surgical group patients than in ER criteria patients. In the expanded criteria group, the sub-group of patients with intramucosal, undifferentiated adenocarcinoma measuring 20 mm or less had a significantly greater number of identified SNs (p = 0.013) and SN basins (p = 0.032). Furthermore, SN metastasis was observed only in this group. CONCLUSIONS: Patients with intramucosal, nonulcerated, undifferentiated adenocarcinoma measuring 20 mm or less could develop a lymphatic network. For these patients, careful follow-up is required after ER.

Hemodynamic stress distribution identified by SPECT reflects ischemic symptoms of Moyamoya disease patients.

This study aimed to validate the hypothesis that the ratio of cerebral blood flow (CBF) at rest in the lenticular nucleus (LN) territory to that in the middle cerebral artery (MCA) territory is higher in symptomatic Moyamoya disease (MMD) patients than in asymptomatic MMD patients. This was a retrospective observational study of adult patients with documented MMD who underwent single-photon emission computed tomography (SPECT) and had been examined at the Department of Neurosurgery of Keio University Hospital during a 10-year period (2006-2016). The diagnosis was made on the basis of typical imaging findings. We classified unoperated MMD patients into three groups: class I, no evidence of stenosis or occlusion hemispheres and without symptoms in unilateral MMD patients; class II, hemispheres with stenosis or occlusion but without ischemic symptoms; and class III, hemispheres with evidence of stenosis or occlusion associated with ischemic symptoms. Hemodynamic stress distribution (hdSD) was defined as the ratio of CBF in one LN to the CBF in the peripheral MCA; this was obtained by SPECT at rest. We compared the values of CBF and hdSD among the groups. A total of 173 adult patients were diagnosed with MMD from January 1, 2006, to January 1, 2016. Among them, 85 MMD patients underwent SPECT studies. After excluding inappropriate cases, 144 hemispheres were included in our analysis. hdSD was significantly higher (p < 0.001) in hemispheres with ischemic symptoms (class III, mean hdSD = 1.1; 36 sides) than in those without symptoms (class II, mean hdSD = 1.03; 82 sides). However, CBF at rest in the MCA or LN was not significantly associated with ischemic symptoms. The optimal threshold for hdSD to have ischemic symptoms was 1.040 (area under the curve; 74% sensitivity 91.7% and specificity 54.9%). We used SPECT to investigate cerebral blood from MMD patients and found that high hdSD values were predictive of ischemic symptom development in these patients.

Risk factors for lymph node metastasis in non-sentinel node basins in early gastric cancer: sentinel node concept.

BACKGROUND: Sentinel node (SN) concept is being applied to early gastric cancer. However, when SNs are positive for metastasis, it is unclear how often LNs in other LN basins show metastasis. We aimed to investigate LN metastasis possibility in LN basins without SNs (non-SN basins). We determined risk factors for metastasis in non-SN basins and identified a prediction model for non-SN basin metastasis using classification and regression tree (CART) analysis. METHODS: We enrolled 550 patients who were diagnosed with cT1N0M0 or cT2N0M0 gastric cancer with a single lesion and underwent SN mapping. We adopted a dual-tracer method using a radioactive colloid and blue dye to detect SNs. RESULTS: Of all, 45 (8.2%) patients had SN metastasis; we divided them into two groups: LN metastasis positive and LN metastasis negative in non-SN basins. Univariate analysis showed that the groups differed significantly regarding lymphatic invasion (p = 0.007), number of identified SNs (p = 0.032), and macrometastasis in SN basins (p = 0.005). The CART decision tree for predicting LN metastasis in non-SN basins had area under the curve value of 0.86. Moreover, there were significantly differences in cancer-specific survival (CSS) between the two groups (p = 0.028). CONCLUSIONS: Macrometastasis in SN basins, lymphatic invasion, and number of identified SNs ≥ 5 are risk factors for LN metastasis in non-SN basins among gastric cancer patients. We identified a prediction model with CART analysis; patients with macrometastasis in SN basins and lymphatic invasion were considered to be at the highest risk for LN metastasis.

Potential for local resection with sentinel node basin dissection for early gastric cancer based on the distribution of primary sites.

BACKGROUND: Based on the sentinel node (SN) concept, function-preserving surgery with SN basin dissection (SNBD) can be performed for SN-negative early gastric cancers. Particularly, a resection area can be minimized when the SN basin and primary site are closely localized. The aim of this study was to compare probabilities of being candidates for local resection with SNBD based on tumor location among patients with early gastric cancer. METHODS: We retrospectively analyzed 358 patients who underwent surgery with SN mapping for gastric cancer in our institution from November 1999 to April 2014. The proportion of patients who had a localized single basin and the distributions of the SN basins and primary sites were investigated. Patients with single basin drainage excluding remote sentinel node basin were considered as candidates for local resection with SNBD. RESULTS: Of the 358 patients, 191 (53%) patients were considered eligible for local resection with SNBD. Patients with tumors located in the upper third of the stomach were more likely candidates for local resection than those with tumors in other locations (upper third, 68%; middle third, 50%; and lower third, 51%), whereas patients with tumors located in the anterior wall were less likely candidates than those with tumors other locations (anterior wall, 31%; posterior wall, 58%; greater curvature, 55%; and lesser curvature, 57%). CONCLUSION: We found that > 50% of the patients indicated for SN navigation surgery, particularly those with tumors in the upper third of the stomach, potentially could undergo partial resection with SNBD.

Can we predict amyloid deposition by objective cognition and regional cerebral blood flow in patients with subjective cognitive decline?

BACKGROUND: Subjective cognitive decline (SCD) may herald the first symptoms of Alzheimer's disease (AD) whereas individuals with beta-amyloid (Aß) deposition are regarded as a high-risk group for AD. Recently, amyloid positron emission tomography (PET) studies have demonstrated clinical and cognitive feature differences between Aß-positive and negative SCD, but details of their differences remain unclear. We aimed to investigate the relationships among Aß deposition, clinical, and cognitive features in patients with SCD. METHODS: Forty-two patients with SCD (22 women, 74.5 ± 4.7 years) were examined using fluorine-18 florbetaben PET and were divided into Aß-positive (n = 10) and negative (n = 32) groups. We compared cognitive and psychological outcomes, and single photon emission computed tomography (SPECT) imaging data between the two groups. In addition, a linear regression analysis was performed to assess relationships between the severity of SCD and neuropsychological tests, affective scores, and demographic factors. RESULTS: The rate of score changes from the immediate recall to delayed recall in the logical memory subtest of the Wechsler's Memory Scale Revised were different between the groups (P = 0.04). However, the binary logistic regression analysis showed no significant differences between the two. In addition, the severity of SCD was significantly strong in women (P = 0.002). Furthermore, within the Aß-negative group, subjective memory loss correlated with word fluency category score (P = 0.023) and apathy scale (P = 0.037). CONCLUSIONS: No significant differences were observed between Aß-positive and -negative SCD on any of the neuropsychological measures, clinical measures, or SPECT imaging. Further, the severity of SCD was not predicted by the symptoms of anxiety, depression, or neuropsychological examination.

The psychological impact of disclosing amyloid status to Japanese elderly: a preliminary study on asymptomatic patients with subjective cognitive decline.

ABSTRACTIn Japan, 4.6 million people are living with dementia and the number is expected to rise to 7 million by 2025. Amyloid-ß (Aß) positron emission tomography (PET) is used for cognitively normal Japanese people with or without subjective cognitive decline (SCD) for the purpose of clinical trials or diagnosis. Nevertheless, no empirical studies have been conducted on the safety of disclosing amyloid status to such populations. We conducted amyloid PET imaging on 42 participants (Aß positive (n = 10) and negative (n = 32)). State anxiety and depression were measured at pre- and post-disclosure, and test-related distress at post-disclosure. Mean state anxiety and depression scores were below the cut-off through pre- and post-disclosure in the Aß positive and negative groups. State anxiety and depression did not change over time and were not different between groups. Mean test-related distress scores were within normal limits at post-disclosure in both groups. No significant difference was found between groups. Disclosing Aß positive results did not cause greater mood disturbance than negative results in a short period of time. The short-term psychological safety of disclosing Aß PET results to asymptomatic Japanese adults with SCD was indicated.

A Comparison of Dye Versus Fluorescence Methods for Sentinel Lymph Node Mapping in Endometrial Cancer.

OBJECTIVE: Sentinel nodes (SNs) have been observed in several reports from Japan and overseas in cases with endometrial cancer; however, no consensus has been reached regarding the types of tracers or the method of their injection. A combination of the radioisotope (RI) and dye method is considered to be desirable. We assessed SN mapping using either dye or near-infrared fluorescence imaging to clarify a suitable method in cases of endometrial cancer. METHODS: Patients were enrolled from 92 patients diagnosed with endometrial cancer and having no extrauterine metastasis by the preoperative imaging between 2009 and 2014 at our institution. To identify the SNs, we performed 3 methods using either dye or fluorescence solutions in conjunction with a RI method. In the dye method, we injected indocyanine green in the uterine subserosa, visually identifying SNs as stained green. In the fluorescence method, a dilute indocyanine green solution (0.5 mg, fluorescence A or 0.25 mg, fluorescence B, each per 10 mL of solvent) was injected and the SN identified by the HyperEye Medical System. RESULTS: The SN detection rates were 100%, 100%, and 96% using dye and fluorescence A or B solution, respectively. Pelvic SNs were detected by the 3 methods in 98%, 100%, and 96% of cases and para-aortic SNs in 65%, 88%, and 74%, respectively. Fluorescence A solution was somewhat better than dye in detecting para-aortic SNs, although not significantly so (P = 0.07). The sensitivity and negative predictive values for detecting SNs with metastases with the dye method were 92% and 98% compared with 100% and 100%, respectively, for both fluorescence solutions. CONCLUSIONS: Although both dye and fluorescence methods performed well, no method perfectly identified para-aortic SNs. The concomitant use of the RI method is required to detect para-aortic SNs.

Extremely Low Prevalence of Amyloid Positron Emission Tomography Positivity in Parkinson's Disease without Dementia.

BACKGROUND: Most cases of dementia with Lewy bodies (DLB) show Alzheimer's disease pathology-like senile plaques and neurofibrillary tangles. Several studies have also revealed a high prevalence of positive amyloid imaging with positron emission tomography (PET) in DLB and moderate prevalence in Parkinson's disease (PD) with dementia. However, it remains unclear in PD without dementia as to when the brain ß amyloid (Aß) burden begins and progresses. Our study aimed to determine the prevalence of Aß deposition in PD without dementia using amyloid PET. METHODS: This was a cross-sectional study on 33 patients with PD without dementia, of whom 21 had normal cognition and 12 met the criteria for PD-mild cognitive impairment. All subjects underwent neuropsychological assessment and [18F] florbetaben (FBB) PET. RESULTS: All subjects had Lewy body-related disorders, displaying a significantly reduced myocardial [123I] metaiodobenzylguanidine uptake. The cortical FBB-binding pattern in all subjects, including APOE e4 carriers, suggested negative Aß deposition. CONCLUSION: Patients with PD without dementia exhibit an extremely low prevalence of Aß positivity compared with those reported in cognitively normal elderly controls. Further longitudinal imaging studies and long-term follow-up are needed; however, our findings provide novel insights for understanding Aß metabolism in PD.

Pylorus-Preserving Surgery Based on the Sentinel Node Concept in Early Gastric Cancer.

BACKGROUND: In patients with early stage gastric cancer in the middle third of the stomach, pylorus-preserving gastrectomy (PPG) can be an option as function-preserving surgery, although its oncologic safety is not definitively defined. This issues may be overcome using the sentinel node (SN) concept. The aim of this study was to investigate the effectiveness of the SN concept in early gastric cancer patients who are candidates for PPG. METHODS: One hundred fifty-six patients with middle-third location of cT1N0 gastric cancer (single lesion, <4 cm) underwent distal gastrectomy with SN mapping. As a tracer, technetium-99 tin colloid solution and blue dye were endoscopically injected into the submucosal layer surrounding the primary tumor. RESULTS: SN detection rate was 100 % (156 of 156), and the accuracy of the nodal evaluation of metastasis was 99 % (155 of 156). Suprapyloric lymph node (LN; LN No. 5) and infrapyloric LN (LN No. 6) were detected as SNs in 6 and 14 % of the patients, respectively. We also found two cases with metastasis to LN No. 5 or LN No. 6. DISCUSSION: When performing PPG, the possibility of LN metastasis, especially to LN No. 5 and LN No. 6, cannot be underestimated. SN mapping can play an important role to predict the possibility of metastasis to LN No. 5 and LN No. 6.

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.

Sentinel lymph node mapping for 385 gastric cancer patients.

BACKGROUND: The objectives were to investigate the accuracy of sentinel lymph node (SLN) biopsy, detect the predictors for undetected or false-negative cases, evaluate the indications for SLN-navigated gastrectomy, and characterize the problems of SLN mapping in gastric cancer. The SLN concept may be applicable to early gastric cancer, particularly clinical T1N0M0 or T2N0M0 with tumor diameter ≤4 cm. METHODS: A total of 385 consecutive patients diagnosed with cT1N0M0 or cT2aN0M0 operable gastric cancer from April 1999 to December 2007 underwent radical gastrectomy with SLN mapping. SLNs were identified using radio-guided and dye-guided methods. Predictors for undetected or false-negative cases on SLN mapping were examined by multivariate regression analysis. RESULTS: The detection rate of hot and/or blue nodes was 96.6% (372 of 385). The accuracy of metastatic status based on SLNs was 98.9% (368 of 372) for all cases in whom SLNs could be detected. Furthermore, the accuracy of metastatic status based on SLNs was 99.1% (344 of 347) in cT1 gastric cancer and 96.0% (24 of 25) in cT2 gastric cancer. Pathologically, the tumors invaded to the muscularis propria or deeper in three of four false-negative cases. All but one case had metastatic lymph nodes within the sentinel basins. In terms of 5-y recurrence free survival, positive SLN cases (SLN(+)) had a worse prognosis than negative SLN cases (SLN(-); P = 0.008). Moreover, SLN(+) and non-SLN(-) cases (SLN(+)/non-SLN(-)) had a similar prognosis as SLN(+) and non-SLN(+) cases (SLN(+)/non-SLN(+)) (P = 0.511). On multivariate regression analysis, undetected or false-negative cases were significantly associated with the time period. CONCLUSIONS: The present results appeared to validate the SLN concept for untreated cT1 gastric cancer with tumor diameter ≤4 cm. SLN mapping may provide an effective method of staging the lymph node status of patients undergoing minimized gastrectomy. Sentinel basin dissection guards against the possibility of leaving positive lymph nodes. Stabilization of the procedure and experience with SLN mapping in gastric cancer might decrease undetected or false-negative cases.

Auxiliary diagnosis of lymph node metastasis in early gastric cancer using quantitative evaluation of sentinel node radioactivity.

BACKGROUND: Sentinel node (SN) mapping using dye and radioisotope (RI) tracer has been reported to be feasible in cases of early gastric cancer. Because accurate diagnosis of micrometastasis is sometimes difficult in the limited time available during surgery, a faster and simpler method of improving the intraoperative diagnostic precision of lymph node metastasis is needed. The amount of tracer deposited in an SN can be determined from its radioactivity; however, the significance of the RI count has not been fully discussed. We investigated the clinical impact of the RI count when used as an adjunct to conventional lymph node dissection when diagnosing lymphatic metastasis in cases of early gastric cancer. METHODS: From 2008 to 2009, patients with clinically diagnosed T1N0M0 gastric cancers who underwent gastrectomy and SN mapping were enrolled. SNs were examined by intraoperative and postoperative pathology. The RI count was measured for each SN with a handheld gamma probe; the correlation between nodal metastasis and the RI count was assessed. RESULTS: A total of 308 SNs were harvested from 72 patients. Patients with SN metastasis had significantly higher total RI counts than those without SN metastasis (p = 0.007). Among cases with SN metastasis, RI counts were also significantly elevated in metastasis-positive nodes, stations, and basins. In these cases, the most of SNs having the highest RI count in each case had metastasis including isolated tumor cells. CONCLUSION: In early gastric cancer patients, a high RI count from an SN was correlated with lymph node metastasis. Therefore, RI counting may aid efficient pathological diagnosis and focused lymph node dissection.

Clinical significance of the anterosuperior lymph nodes along the common hepatic artery identified by sentinel node mapping in patients with gastric cancer.

BACKGROUND: The sentinel node (SN) concept is safely applied and validated in early gastric cancer. Gastric lymph nodes are divided into five basins with the main gastric arteries, and the anterosuperior lymph nodes with the common hepatic artery (No. 8a) are classified in the right gastric artery (r-GA) basin. Although No. 8a are considered to have lymphatic flow from the r-GA basin, there might be additional multiple lymphatic flows into No. 8a. The aim of this study is to analyze the lymphatic flows to No. 8a and to investigate the clinical significance of No. 8a as a sentinel node (SN No. 8a). METHODS: Four hundred and twenty-nine patients with cT1N0 or cT2N0 gastric cancer underwent SN mapping. We used technetium-99 tin colloid solution and blue dye as a tracer. RESULTS: We detected SN No. 8a in 35 (8.2 %) patients. In these patients, we detected SN No. 8a with SNs that belonged to the left gastric artery (l-GA) basin (66 %), right gastroepiploic artery (r-GEA) basin (54 %), and right gastric artery (r-GA) basin (46 %). In addition, celiac artery lymph nodes were detected as SNs significantly more frequently. Function-preserving surgery was performed significantly less often in patients with SN No. 8a (p =0.018). CONCLUSIONS: We found that SN No. 8a seemed to have lymphatic flow not only from the r-GA basin, but also from the l-GA basin or r-GEA basin. When SN No. 8a are detected, we should be careful to perform function-preserving surgery, even in SN-negative cases.

Oral Nitrate Administration Ameliorates Cardiogenic Shock due to Eclipsed Mitral Regurgitation.

Eclipsed mitral regurgitation (MR) has been reported as transient massive functional MR caused by a sudden coaptation defect in the absence of left ventricular remodeling or epicardial coronary artery stenosis. Coronary spasm or microvascular dysfunction has been suggested to be associated with the pathogenesis. Here, we present a 68-year-old woman with eclipsed MR with cardiogenic shock ameliorated by nitrate. She was admitted for transient shock with massive functional MR. Transient MR was associated with a complete absence of mitral leaflet coaptation owing to tethering of the lateral posterior mitral leaflet. The leaflet tethering was triggered by transient myocardial ischemia around the anterolateral papillary muscle, which could have been caused by coronary spasm and/or microvascular dysfunction. During admission, she experienced similar repeated episodes, which were ameliorated by oral nitrate administration. This is the first described case of eclipsed MR with shock ameliorated by nitrate. Although eclipsed MR, a cause of life-threatening shock, is uncommon, we need to keep in mind that nitrate administration could be a treatment option even in patients with cardiogenic shock.

Suitability of sentinel node mapping as an index of metastasis in early gastric cancer following endoscopic resection.

BACKGROUND: When pathological diagnosis following endoscopic resection (ER) for early gastric cancer (EGC) suggests probable lymph node metastasis, additional surgery with lymphadenectomy should be performed. The sentinel node (SN) concept has yet to be applied to tumors following ER. The aim of this study was to evaluate the feasibility of SN navigation surgery for such tumors. METHODS: Forty patients diagnosed with EGC lesions <4 cm in diameter underwent gastrectomy with SN mapping following ER. A technetium-99 m tin colloid solution and a dye were injected into the submucosal layer around the post-ER scar in all four abdominal quadrants. We then compared the SN distribution and metastases among the patients who underwent ER and controls (n = 192). RESULTS: SNs were identifiable in all patients, and the mean number of SNs per case was 4.9. The location of the SN basin was similar in the patients who underwent ER and the controls. One patient (3 %) whose primary tumor had invaded the submucosal layer had a metastatic SN. The median time from ER to surgery was 73 days. No postoperative recurrence was observed in any patient over a median follow-up of 1,023 days. CONCLUSIONS: Our findings suggest that the SN basin is not greatly affected by ER. The SN concept could be suitable for tumors following ER, but conventional gastrectomy with lymphadenectomy involving the SN basin should be used at present.

Sentinel node mapping in adenocarcinoma of the esophagogastric junction.

BACKGROUND: The incidence of adenocarcinoma of the esophagogastric junction (AEG) is increasing, but the surgical strategy for AEG remains controversial. We hypothesized that sentinel node (SN) mapping for AEG could be validated to avoid unnecessary lymphadenectomy and permit minimally invasive surgery. We examined the feasibility of SN mapping for AEG. METHODS: We enrolled 15 patients with preoperatively diagnosed cT1 N0 M0 primary AEG (Siewert type I, N = 3; Siewert type II, N = 12) lesions measuring <4 cm in diameter. The dual tracer method employing radioactive colloid and blue dye was used to detect SNs. The distribution of SNs was compared with that of metastatic lymph nodes in 52 patients who were surgically treated without SN mapping. RESULTS: SNs were successfully identified in all the patients. Two patients with lymph node metastasis had positive SNs identified via an intraoperative pathological examination, and the diagnostic sensitivity and accuracy based on the SN status were both 100 %. For Siewert type II AEG, the SNs were not detected in the lower mediastinum by intraoperative gamma probing. Thus, all surgical procedures were performed via a transhiatal approach. No patient without SN metastasis experienced cancer recurrence during a 38-month median follow-up. The distribution of SNs was similar to that of lymph node metastasis in the patients who were surgically treated without SN mapping. CONCLUSIONS: We achieved 100 % SN detection. Our results suggested that SN mapping is feasible for AEG and highly sensitive and accurate in diagnosing lymph node metastasis. SN mapping may clarify the necessity of mediastinal lymph node dissection and individualize minimally invasive surgery.

Application of nuclear medicine to achieve less invasive surgery for malignant solid tumors in children.

BACKGROUND: The use of nuclear medicine for the management of malignant tumor, such as radioguided surgery and sentinel lymph node biopsy (SLNB), has been widely accepted in the adult practice. However, there are very few studies to apply those techniques for pediatric diseases. The aim of this study was to investigate the feasibility of application of nuclear medicine in surgery for neuroblastoma (NB) or rhabdomyosarcoma (RMS) in children. METHODS: Radioguided surgery using (123) I-metaiodobenzylguanidine was performed on six children with NB. SLNB using technetium-labeled tin or sulfur colloid was performed on two children with perineal RMS. Histological evaluation of resected specimens was performed to determine the accuracy of intraoperative detection and SLNB. All patients were evaluated for overall survival and complications. RESULTS: Intraoperative tumor localization using hand-held gamma probe was helpful in 85.7% of NB patients. Sensitivity and specificity of this technique were 81.8% and 93.3%, respectively. There were no postoperative complications, and four out of five patients with high-risk NB experienced disease-free survival (median follow up, 57 months). Sentinel lymph nodes were easily detected in patients with perineal RMS, and histological assessment revealed complete consistency with regional lymph node status. CONCLUSIONS: Nuclear medicine may have a potential application in the use of less invasive surgery for advanced NB or perineal RMS, the two most challenging pediatric malignancies.