Detection Rate Of Metastases Research Articles

Is Unenhanced 18F-FDG–PET/CT Better than Enhanced CT in the Detection of Retropharyngeal Lymph node Metastasis in Nasopharyngeal Carcinoma?

Positron-emission tomography/computed tomography (PET/CT) has been proposed as a means to enhance the pretreatment evaluation of cervical lymph node status in patients with nasopharyngeal carcinoma (NPC). We conducted a prospective study to compare PET/CT and enhanced CT for the detection of retropharyngeal lymph node (RLN) metastasis in NPC, and to ascertain the factors that affect its diagnostic performance. Our study population was made up of 33 patients-24 men and 9 women, aged 30 to 81 years (mean: 52)-with newly diagnosed NPC who had been treated over a 2-year period. All patients underwent enhanced CT first, followed by unenhanced 18F-fluorodeoxyglucose (FDG) PET/CT. The detection rate of RLN metastasis on PET/CT was significantly lower than that on enhanced CT (36.4 vs. 75.8%; p < 0.001). A total of 25 of 26 nodes with a discordant finding were negative on PET/CT; they included 13 metastatic lymph nodes with low FDG uptake, 9 that were located close to the primary tumor, 2 that were confluent RLNs, and 1 that was adjacent to the physiologic FDG-avid prevertebral muscle. The maximum standardized uptake value (SUVmax) of RLNs was positively correlated with the minimum axial diameter (r = 0.803, p < 0.001). The PET/CT detection rate was 0% for lymph nodes smaller than 5 mm, 9% for those 5 to 10 mm, and 73% for those 1 cm or larger. The detection rate of PET/CT at level C1 was significantly lower than that at C2 (22 vs. 67%; p = 0.035). We conclude that unenhanced PET/CT is markedly inferior to enhanced CT for detecting RLN metastasis in NPC, especially in lymph nodes with a minimum axial diameter of less than 1 cm and those in proximity to the primary tumor. Using enhanced CT in PET/CT is justified to improve the recognition of RLN metastasis in patients with NPC.

Abstract B38: Identification of highly metastatic disseminating tumor cells in late-stage liver cancer lung metastasis

Abstract As the 6th most frequent cancer worldwide, liver cancer is the 2nd leading cause of cancer death globally due to its often late detection and high rate of metastasis. Although relatively uncommon in the United States, a recent study led by AACR has projected it will surpass breast, prostate, and colorectal cancers to become the third leading cause of cancer death in US by 2030. Therefore, there is an urgent need to understand the biology driving liver cancer metastasis, particularly the late-stage metastasis, in order to develop more efficacious therapies to improve the poor prognosis. We have previously shown that inactivation of the conditional Pten and p53 alleles in a Prom1-expressing progenitor population induced the formation of liver cancer with almost 100% penetrance. 3-5% of these liver tumors metastasized to the lung, the predominant metastatic site of liver cancer. By enriching the tumorigenic cancer stem cells from the primary tumors via in vitro liver stem cell culture, in combination with a novel ultrasound-guided intrahepatic implantation method we developed, we established a series of highly metastatic orthotopic liver cancer allograft mouse models with &amp;gt;60% lung metastasis rate. These mice also developed extensive intrahepatic metastases as well as invasions and metastases into the abdominal organs, predominantly in the diaphragm, peritoneum, lymph nodes in the omentum and mesentery. In more severe cases, metastases are also found in the stomach, intestine, kidney, ovary and uterus. Cross-species comparison has demonstrated the high resemblance of our model to human liver cancer at both histological and genomic levels. All tumor cells used in this model carry a strong GFP reporter that allows their easy identification during metastasis. We primarily focused on the lung metastasis for its clinical significance. Very interestingly, in addition to identifying GFP+ tumor cells in the bulk of the metastases (metastasis tumor cells, or MTCs), we consistently discovered large numbers of GFP+ disseminating tumor cells (DTCs) in the surrounding normal-looking lung tissues. Our further analyses have indicated that MTCs and DTCs are two biologically distinct tumor cell populations. There is a complete lack of intercellular organization of DTCs compared to MTCs and they proliferated at a much lower rate than MTCs. Most importantly, when MTCs and DTCs were isolated from the same lung and re-implanted in the liver of a new host, we consistently found that MTCs retained very limited ability to re-metastasize to the lung upon re-implantation even though they were isolated from lung metastases. Instead, MTCs formed large tumors at the implantation site and developed extensive intrahepatic metastases. High-grade invasions into surrounding abdominal organs are also evident. On the contrary, DTCs grew significantly slower and less aggressively when implanted back into the liver. However, they exhibited much higher metastatic ability than MTCs by rapidly forming large multifocal lung metastases and killed animals within a shorter time of period. In fact, those secondary lung metastases formed by DTCs are the largest among all the lung metastases identified in the entire cohort of this liver cancer allograft model (n&amp;gt;50). This striking capacity of DTCs to form metastases that is superior to that of MTCs has strongly suggested the necessity to target both cell populations in late-stage liver cancer metastasis in order to effectively prevent the growth and further spreading of metastases. We are currently conducting systematic molecular dissection of DTCs and MTCs by RNA-seq gene expression profiling and proteomics to map their molecular features and to identify potential druggable molecular targets specifically tailored to each population. Citation Format: Liyuan Li, Melissa Johnson, Christopher Calabrese, David Finkelstein, Armita Bahrami, Dolores Lopez-Terrada, Liqin Zhu. Identification of highly metastatic disseminating tumor cells in late-stage liver cancer lung metastasis. [abstract]. In: Proceedings of the AACR Special Conference on Tumor Metastasis; 2015 Nov 30-Dec 3; Austin, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(7 Suppl):Abstract nr B38.

Robot-Assisted Extended Pelvic Lymph Nodes Dissection for Prostate Cancer: Personal Surgical Technique and Outcomes.

ABSTRACTObjective:Extended pelvic lymph nodes dissection (EPLND) allows the removal of a higher number of lymph nodes than limited PLND. The aims of this study were to describe our robot-assisted EPLND (RAEPLND) technique with related complications, and to report the number of lymph nodes removed and the rate of lymph nodal metastasis.Materials and Methods:153 patients underwent RAEPLND prior to robot-assisted radical prostatectomy (RARP). Indications were defined according to Briganti nomogram, to predict risk of lymph-nodal metastasis. Lymphatic packages covering the distal tract of the common iliac artery, the medial portion of the external iliac artery, the external iliac vein and the internal iliac vessels, together with the obturator and the presacral lymphatic packages were removed on both sides.Results:Median preoperative PSA was 7.5 ng/mL (IQR 5.5–11.5). Median operative time was 150 min (135–170). Median RAEPLND alone operative time was 38 min (32.75–41.25); for right and left side, 18 (15–29) and 20 min (15.75–30) (p=0.567). Median number of lymph nodes retrieved per patient was 25 (19.25–30); 13 (11–16) and 11 (8–15) for right and left side. In 19 patients (12.41%) metastasis was found at the level of pelvic lymph nodes. Median number of positive lymph nodes was 1 (1–4.6) per patient. Complications occurred in 11 patients (7.3%).Conclusions:the number of lymph nodes removed was comparable to published data about open series, allowing the increase of detection rate of lymph nodal metastasis for minimally invasive approach without compromising complications' rate if performing the procedure following reported technique.

Comparison of semi-extended and standard lymph node dissection in radical prostatectomy: A single-institute experience.

Standard lymphadenectomy for prostate cancer is limited to the obturator lymph nodes (LNs), although the internal and external iliac LNs represent the primary landing zone for prostatic lymphatic drainage. We performed anatomically semi-extended pelvic lymph node dissection (PLND) to assess the incidence of LN metastasis in cases of clinically localized prostate cancer. A total of 730 consecutive patients underwent radical prostatectomy with either semi-extended PLND, comprising 6 selective fields, namely the external iliac, internal iliac and obturator LNs bilaterally, or standard LND (obturator LNs alone). A total of 131 patients undergoing semi-extended PLND were compared with 599 patients undergoing standard LND. The patients were stratified into high-risk [prostate-specific antigen (PSA)>20 ng/ml, Gleason score (GS)≥8], intermediate-risk (PSA 10-20 ng/ml, GS=4+3) and low-risk (PSA<10 ng/ml, GS≤3+4) subgroups. Following semi-extended LND, positive LNs were detected in 12/61 (20%) of the high-risk, 1/30 (3%) of the intermediate-risk and 0/40 (0%) of the low-risk cases. Following standard LND, positive LNs were detected in 13/182 (7%) of the high-risk, 1/164 (0.6%) of the intermediate-risk and 0/253 (0%) of the low-risk cases. In high-risk patients, the detection rate of LN metastasis was significantly higher following extended LND compared with standard LND (P<0.01). In 9 of 13 patients (69%), metastases were identified in the internal and external iliac regions, despite negative obturator LNs. There were no significant differences regarding intraoperative and postoperative complications or blood loss in the two groups. There was no lymphocele formation in patients undergoing either standard or semi-extended LND. Extended pelvic LND (PLND) is associated with a high rate of LN metastasis detection outside the fields of standard LND in cases with clinically localized prostate cancer. Therefore, LND including the internal and external iliac LNs should be performed in all patients with high-risk prostate cancer; however, in the low-risk group, PLND may be omitted.

Staging Laparoscopy for Patients with cM0, Type 4, and Large Type 3 Gastric Cancer.

Staging laparoscopy (SL) is considered useful for detecting peritoneal metastasis, a task that is difficult using conventional imaging modalities. However, indications for the procedure remain unclear, with differences evident across reports. The present study aimed to clarify the effectiveness and limitations of SL for patients with type 4 and large type 3 gastric cancer. We included 88 patients with cM0, type 4 or large type 3 gastric cancer who underwent SL at the Shizuoka Cancer Center from August 2008 to June 2014, to determine the detection rate of peritoneal metastasis by SL. In addition, we calculated the false-negative rate of SL by recruiting patients who were diagnosed as P0 at SL and underwent laparotomy within 28 days after the SL. P0CY0, P0CY1, P1CY0, and P1CY1 were diagnosed in 41 (46.6 %), 15 (17.0 %), 15 (17.0 %), and 17 (19.3 %) patients, respectively. Accordingly, clinically non-evident peritoneal metastasis was found in 36.3 % of patients, and 53.4 % of patients were diagnosed with stage IV. In addition, 29 patients diagnosed as P0 at SL underwent laparotomy within 28 days after the SL. Among them, peritoneal metastasis was found in five patients. Thus, the false-negative rate was 17.2 % (5/29, 95 % CI 7.6-34.6 %). SL is useful for detecting previously unsuspected peritoneal metastasis and for avoiding unnecessary laparotomy, although the high false-negative rate cannot be ignored. Patients with cM0, type 4, and large type 3 gastric cancer are considered suitable candidates for SL.

Initial Experience of 68Ga-PSMA PET/CT Imaging in High-risk Prostate Cancer Patients Prior to Radical Prostatectomy

Prostate-specific membrane antigen (PSMA) overexpression theoretically enables targeting of prostate cancer (PCa) metastases using gallium Ga 68 (68Ga)–labeled PSMA ligands for positron emission tomography/computed tomography (PET/CT) imaging. Promising detection rates have been reported when using this approach for functional imaging of recurrent PCa; however, until now, the diagnostic accuracy of 68Ga-PSMA PET/CT for preoperatively identifying lymph node metastases (LNMs) had not been assessed. We retrospectively compared preoperative 68Ga-PSMA PET/CT lymph node (LN) findings with histologic work-up after radical prostatectomy (RP). Overall, 608 LNs containing 53 LNMs were detected during RP. LNMs were present in 12 of 30 patients (40%). The 68Ga-PSMA PET/CT scans identified 4 patients (33.3%) as LN true positive and 8 patients (66.7%) as false negative. Median size of 68Ga-PSMA-PET/CT–detected versus undetected LNMs was 13.6 versus 4.3mm (p<0.05). Overall sensitivity, specificity, positive predictive value, and negative predictive value of 68Ga-PSMA PET/CT for LNM detection were 33.3%, 100%, 100%, and 69.2%, respectively. Per-side analyses revealed corresponding values of 27.3%, 100%, 100%, and 52.9%. Conversely, 68Ga-PSMA PET/CT enabled tumor visualization in the prostate. In 92.9% of patients, the intraprostatic tumor foci were correctly predicted. Overall, 68Ga-PSMA PET/CT is a promising tool for functional imaging; however, our initial experience revealed substantial influence of LNM size on the diagnostic accuracy of 68Ga-PSMA PET/CT. Patient summaryWe assessed the diagnostic accuracy of 68Ga-PSMA PET/CT in high-risk prostate cancer patients prior to radical prostatectomy. We found that lymph node metastasis detection rates were substantially influenced by lymph node metastasis size.

Application of computed tomography virtual noncontrast spectral imaging in evaluation of hepatic metastases: a preliminary study.

Objective:The objective was to qualitatively and quantitatively evaluate hepatic metastases using computed tomography (CT) virtual noncontrast (VNC) spectral imaging in a retrospective analysis.Methods:Forty hepatic metastases patients underwent CT scans including the conventional true noncontrast (TNC) and the tri-phasic contrast-enhanced dual energy spectral scans in the hepatic arterial, portal venous, and equilibrium phases. The tri-phasic spectral CT images were used to obtain three groups of VNC images including in the arterial (VNCa), venous (VNCv), and equilibrium (VNCe) phase by the material decomposition process using water and iodine as a base material pair. The image quality and the contrast-to-noise ratio (CNR) of metastasis of the four groups were compared with ANOVA analysis. The metastasis detection rates with the four nonenhanced image groups were calculated and compared using the Chi-square test.Results:There were no significant differences in image quality among TNC, VNCa and VNCv images (P > 0.05). The quality of VNCe images was significantly worse than that of other three groups (P < 0.05). The mean CNR of metastasis in the TNC and VNCs images was 1.86, 2.42, 1.92, and 1.94, respectively; the mean CNR of metastasis in VNCa images was significantly higher than that in other three groups (P < 0.05), while no statistically significant difference was observed among VNCv, VNCe and TNC images (P > 0.05). The metastasis detection rate of the four nonenhanced groups with no statistically significant difference (P > 0.05).Conclusions:The quality of VNCa and VNCv images is identical to that of TNC images, and the metastasis detection rate in VNC images is similar to that in TNC images. VNC images obtained from arterial phase show metastases more clearly. Thus, VNCa imaging may be a surrogate to TNC imaging in hepatic metastasis diagnosis.

The impact of nodal tumour burden on lymphoscintigraphic imaging in patients with melanomas.

To retrospectively study the influence of nodal tumour burden on lymphoscintigraphic imaging in 509 consecutive patients with melanomas. Bidirectional lymphatic drainage, the clear depiction of an afferent lymphatic vessel, time to depiction of the first sentinel lymph node (SLN) and number of depicted and excised nodes were recorded. Nodal tumour load was classified as SLN-negative, SLN micrometastases or macrometastases. In the overall population, using multivariate regression analysis, a short SLN depiction time was significantly associated with the depiction of a greater number of radioactive nodes, a short distance between the primary tumour site and the nodal basin, younger age and lower nodal tumour burden. The proportion of patients with clear depiction of an afferent lymphatic vessel depended on the nodal tumour load (46% in SLN-negative patients, 57% in SLN positive patients, and 69% in patients with macrometastases; P = 0.009). Macrometastasis was significantly associated with delayed depiction of the first radioactive node and a greater number of depicted hotspots. In patients with clinically nonsuspicious nodes, i.e. the classical target group for SLN biopsy, clear depiction of an afferent vessel was significantly associated with a higher number of SLNs during dynamic acquisition, SLN micrometastasis and a higher overall number of metastatic lymph nodes after SLN biopsy plus completion lymphadenectomy. The excision of more than two SLNs did not increase the metastasis detection rate. In patients with bidirectional or tridirectional lymphatic drainage, the SLN positivity rates for the first, second and third basin were 25.4%, 11.7% and 0.0 %, respectively (P = 0.002). In patients with clinically nonsuspicious lymph nodes, clear depiction of an afferent lymph vessel may be a sign of micrometastasis. Macrometastasis is associated with prominent afferent vessels, delayed depiction of the first radioactive node and a higher number of depicted hotspots.

Reappraisal of Mechanical Exfoliating Cytology for the Detection of Peritoneal Dissemination during the Surgical Staging of Epithelial Ovarian Carcinomas and Borderline Tumours

Objective: This study aimed to evaluate the usability of peritoneal swabbing cytology (PSC) with cotton swabs as an effective method for the detection of peritoneal metastasis during the staging laparotomy of epithelial ovarian carcinomas and borderline tumours (EOC/BT). Study Design: One hundred and ninety-two patients with EOC/BT who underwent laparotomy at the Yokohama City University Hospital from 2004 to 2010 were analysed retrospectively. The positive rates of the PSC and ascites/peritoneal-wash cytology (A/PWC) were compared. Results and Conclusion: Both A/PWC and PSC were performed during laparotomy (n = 140). The rate of metastasis detection with A/PWC was significantly higher than with PSC (50.0 vs. 20.7%, p < 0.001 by χ² test). The superior detection ability of A/PWC was observed regardless of the presence of macroscopic peritoneal metastasis in 56 cases with macroscopic peritoneal metastasis, with A/PWC detecting 80.3% of cases versus PSC detecting 37.5% (p = 0.013). In 84 cases without macroscopic peritoneal metastasis, A/PWC detected 29.8% of cases versus 9.5% with PSC (p = 0.003). Our results suggest that PSC is insufficient to evaluate the peritoneal metastasis for the surgical staging of EOC/BT. Other procedures such as subdiaphragmatic A/PWC should be included when possible to maximize the accuracy of diagnosis.

Sentinel and nonsentinel lymph node assessment using a combination of one-step nucleic acid amplification and conventional histological examination

BackgroundClinical significance of intraoperative sentinel lymph node (SLN) metastases detection using one-step nucleic acid amplification (OSNA) has not been thoroughly investigated. The aim of this study was to assess the usefulness of using a combination of OSNA and conventional histological examinations. Materials and methodsWe included 772 consecutive patients with clinical node-negative cTis-cT3 primary breast cancer who underwent SLN biopsy with intraoperative OSNA and multi-section histological examination at our institution. We estimated the concordance rate and compared SLN metastases detection rates between the two methods. We also compared non-SLN metastasis detection rate between patients who tested positive in OSNA and those who tested positive in histology. ResultsAmong 772 patients, SLN metastases were intraoperatively detected in 211 (26.4%) by either OSNA or histology, in 168 (21.8%) by OSNA, and in 150 (19.4%) by histology. The concordance rate between OSNA and histological examination was 89.2%, but only 123 (58.8%) patients tested positive in both OSNA and histology; 45 were positive in OSNA only and 43 were positive in histology only.SLN status as per both OSNA and histology was significantly correlated with the presence of non-SLN metastases and multivariate analysis-identified independent predictive factors of non-SLN metastases. ConclusionsIntraoperative SLN metastases detection may be more accurate with a combination of OSNA and histological examination than with OSNA or histological examination alone. By using both methods, we can reduce the risk of false negative rate in SLN biopsy, and may prevent physicians from overlooking patients with non-SLN metastases.

Comparison of diagnostic ability between 99mTc-MDP bone scan and 18F-FDG PET/CT for bone metastasis in patients with small cell lung cancer

The aim of this study was to compare the diagnostic ability of (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography/computed tomography (PET/CT) with that of (99m)Tc-methylene diphosphonate ((99m)Tc-MDP) bone scan for bone metastasis in staging patients with small cell lung cancer (SCLC). Ninety-five patients with SCLC who underwent both (18)F-FDG PET/CT and (99m)Tc-MDP bone scan for initial staging work-up were retrospectively enrolled. All (18)F-FDG PET/CT and bone scan images were visually assessed. Bone metastasis was confirmed by histopathological results and all available clinical information. Of 95 patients with SCLC, metastatic bone lesions were found in 30 patients, and 84 metastatic lesions were evaluated on a lesion-basis analysis. The sensitivity of (18)F-FDG PET/CT was 100 % on a per-patient basis and 87 % on a per-lesion basis, and there was no false-positive lesion on PET/CT images. In contrast, the sensitivity of the bone scan was 37 % on a per-patient basis and 29 % on a per-lesion basis. The bone scan showed 11 false-positive lesions. The bone scan detected two metastatic lesions that were not detected by PET/CT, which were outside the region scanned by PET/CT. On follow-up bone scan, 21 lesions that were not detected by the initial bone scan but were detected by PET/CT were newly detected. In patients with SCLC, (18)F-FDG PET/CT showed higher detection rate of bone metastasis than (99m)Tc-MDP bone scan. Thus, (18)F-FDG PET/CT can replace bone scan in staging patients with SCLC.

Abstract 720: Identification of novel molecular markers for detecting lymph node metastasis of oral squamous cell carcinoma

Abstract Cervical lymph node metastasis is a potent prognostic factor in oral squamous cell carcinoma (OSCC). Management of occult metastasis is an important issue for the surgeons. Sentinel lymph node biopsy (SLNB) is highlighted for its role in deciding making of neck dissection. We have performed the SLNB for cN0 cases routinely and reported the clinical usefulness. Accurate diagnosis of the metastasis in sentinel lymph nodes is important but depends on a heavy workload of the pathologist. We carried out a clinical study to evaluate a novel automated assay system for cytokeratin 19 (CK19) mRNA, the one-step nucleic acid amplification (OSNA) method, to detect the lymph node metastasis of OSCC. The accuracy of OSNA assay was nearly 95%, but it could not detect occult metastasis in case of no or low expression of CK19 mRNA in the primary tumor. In this study, we attempted to identify novel molecular markers to find the harboring cancer cells in the lymph node. First, we determined the gene expression profiles in 7 metastatic lymph nodes from patients with OSCC, 1 benign lymph node, and 5 salivary gland tissues from non-cancerous patients by microarray analysis. We found the overexpression of 36 genes in all metastatic lymph nodes but not in benign lymph node and salivary glands. Subsequently, we examined the expression of these genes in newly 15 metastatic lymph nodes and 9 benign lymph nodes by real-time quantitative RT-PCR method. Among the 36 genes, the expression of annexin A8-like 2 (ANXA8L2) and desmoglein 3 (DSG3) was commonly detected in metastatic lymph nodes at much higher level but not in benign lymph nodes at all. Furthermore, we retrospectively evaluated the usefulness of these markers with the use of 330 lymph nodes that were histopathologically metastasis-positive in 62 and metastasis-negative in 268. The accuracy of each marker CK19, ANXA8L2 and DSG3 is all near 90%. However, the combination of these markers improved the sensitivity up to 96-100%. Expression of ANXA8L2 and DSG3 was also detected in approximately 3% of the histopathologically metastasis-negative lymph nodes. These results suggested that ANXA8L2 and DSG3 could be useful molecular markers and improve detection rate of occult metastasis. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 720. doi:1538-7445.AM2012-720

Contribution of pelvic and para-aortic lymphadenectomy with sentinel node biopsy in patients with IB2–IIB cervical cancer

Objective:Detection of lymph node involvement in women with IB2–IIB cervical cancer could have a positive effect on survival. We set out to evaluate the incidence of pelvic and/or para-aortic lymph node involvement using the sentinel node (SN) biopsy and its impact on survival.Methods:From 2002 to 2010, 66 women with IB2–IIB cervical cancer underwent a pelvic and paraaortic lymphadenectomy with SN biopsy. Survival between groups according to lymph node status was evaluated.Results:Mean tumour size was 43.5 mm. At least one SN was detected in 69% of the 45 SN procedures performed. Sixteen of these patients had metastatic SN and the false negative rate was 20%. Metastatic pelvic SNs or non-SNs were detected in 33 patients (50%), including pelvic-positive nodes in 26 (40%), pelvic- and paraaortic-positive lymph nodes in seven (11%), and paraaortic skip metastases in two (6%). Positive paraaortic node was the sole determinant for disease-free survival (DFS) and overall survival (OS; P<0.001). Differences in DFS and OS between groups according to the nodal status were observed (P<0.001).Conclusion:SN procedure gave a higher rate of metastasis detection. Further studies are required to evaluate whether pre-therapeutic node staging, including paraaortic and pelvic lymphanedectomy, should be performed.

Early diagnosis of undiscovered nodosity metastasis by hepatic artery Doppler flow imaging perfusion index and contrast-enhanced ultrasound

Objective To investigate the diagnostic value of early undiscovered nodosity metastasis by hepatic artery Doppler flow imaging perfusion index(DPI) and contrast-enhanced ultrasound (CEUS).Methods Six hundred and fifty-five patients were collected who suffered with malignant tumor which is not from liver and without liver metastasis.DPI were detected in all patients first,and then patients of higher DPI were taken CEUS and contrast-enhanced CT(CECT).All the diagnosis were confirmed by operation,biopsy under ultrasound or follow-up.Results After 6 months' follow-up,there were 19 patients found liver metastasis in 562 patients without increase of DPI,and 75 patients found liver metastasis in 93 patients with increase of DPI(DPI＞30％).The negative and the positive predictive value were respectively 96.6％and 80.6％.Seventy-five patients were found 132 liver metastasis who were given CEUS,and 60 patients were found 94 liver metastasis who were given CECT,there was significance difference between them( P ＜0.01).Conclusions The combination of DPI and CEUS can get higher detection rate of liver metastasis. Key words: Ultrasonography; Microbubbles; Liver neoplasms; Neoplasm metastasis; Liver artery; Hemodynamic phenomena

Establishment of Nude mice model of breast cancer osseous metastasis under the support of radio- nuclide bone imaging

Objective To estabish the animal model of breast cancer osseous metastasis. Methods MDA-MB-231BO was injected in left ventricle of hairless mice at the density of 0. 8 ×10^7/ml and 1.0 ×10^7/ml, respectively, and the nude mice model of breast cancer osseous metastasis was detected by radionuclide imaging and X-ray. The survival time, the rate of body weight descending, the extent of osseous metastasis and the rate of metastasis in the organs of the nude mice with breast cancer osseous metastasis were investigated. Results In the 0. 8×10^7/ml group and the 1.0 x 107/ml group, the nude mice model of breast cancer osseous metastasis was established successfully. The extent of osseous metastasis, the rate of body weight descending and the rate of metastasis number/total cellular score of MDA-MB-231 BO in the 1.0 ×10^7/ml group were significantly increased as compared with the 0. 8×10^7/ml group （P 〈0. 05 ,P 〈 0. 01 ）. The survival time in the 0. 8 ×10^7/ml group were longer than that in the 1.0×10^7/ml group sig- nificantly （P 〈0. 05）. The metastasis number of 1.0 ×10^7/ml group was greater than that ofO. 8×10^77/ml group and the detection rate of metastasis by radionuclide imaging was 100%. Conclusion The radionu- clide imaging thchnology can diagnosis early hairless mice osseous metastasis. The nude mice model of breast cancer osseous metastasis was established at the MDA-MB-231BO at the density of 0. 8 ×10^7/ml successfully. The nude mice model simulated the pathologic progress of breast cancer osseous metastasis completely. Key words: Radionaclide imaging; Breast carcinoma ; Osseous metastasis ; Model, animal

Retropharyngeal Node Metastasis in Nasopharyngeal Carcinoma

Objective: PET/CT has been proposed to enhance pretreatment evaluation of cervical nodal status in patients with nasopharyngeal carcinoma (NPC). The purpose of this study was to compare PET/CT and enhanced CT in the detection of retropharyngeal lymph node (RLN) metastasis in NPC, and to ascertain the factors affecting its diagnostic performance. Method: From 2007 to 2008, 33 patients with newly diagnosed NPC were prospectively studied. All patients underwent an enhanced CT scan and FDG-PET/CT. Results: The detection rate of RLN metastasis on PET/CT was significantly lower than that on enhanced CT (36.4% vs 75.8%), Pmax of RLNs was positively correlated with the minimal axial diameter (r=0.803), P &lt; 5 mm, 9% for those 5 to 10 mm, and 73% for those ≥1 cm. The detection rate of PET/CT at C1 level was significant lower than that at C2 level (22% vs 67%, P = .035), suggesting that RLNs in close proximity to the primary tumor hindered the recognition by PET/CT. Conclusion: PET/CT is inferior to enhanced CT in detecting RLN metastasis in NPC, especially in lymph nodes with a diameter less than 1 cm or in close proximity to the primary tumor. Using enhanced CT in PET/CT is complementary in delineating the RLN metastasis in patients with NPC.

Second Place Tie Residents' Competition: comparison of pulmonary nodule detection rates between preoperative CT imaging and intraoperative lung palpation

Background Recent advances in computed tomographic (CT) imaging have improved the detection rate of pulmonary metastasis. The aim of this study was to test the hypothesis that the pulmonary nodule detection rate for preoperative CT imaging and intraoperative palpation are now equivalent. Methods A retrospective review of 108 pulmonary metastasectomies in 84 patients was performed. The number of nodules detected on preoperative CT imaging by radiologist report was compared with the number of malignant nodules identified on pathology. Secondary outcome measures were operative approach and primary malignancy. Results Sarcoma metastases were the most common indication for resection (n = 54 [50%]). Thirty-three percent of metastasectomies were performed using a thoracoscopic approach. When thoracotomy was used, significantly more nodules were palpated and resected than were identified on preoperative CT imaging (3.24 vs 2.12, P < .001). Significantly more of these nodules were confirmed malignant on final pathology (2.40 vs 1.60, P = .01). This difference was not seen for thoracoscopic resections. Conclusions Although the sensitivity of CT imaging has improved, a significant number of malignant pulmonary nodules are detected intraoperatively that are not identified on preoperative imaging. Patients undergoing pulmonary metastasectomy require careful intraoperative palpation of lung parenchyma, and therefore open thoracotomy remains the standard of care.

Which patients benefit from intra-operative assessment of sentinel nodes?

Introduction: Pre-operative axillary imaging with ultrasound is now standard prior to surgery for early breast cancer. Intra-operative sentinel node assessment techniques are used to detect metastasis intra-operatively and proceed to axillary dissection. We evaluated detection rate and type of axillary metastasis, by ultrasound and histopathology.

Nano-imaging of the lymph network structure with quantum dots

Sentinel lymph node diagnosis contributes to operative strategy in cancer surgery. Duringlymph node metastasis, cancer cells first reach the sentinel lymph node (SLN) via lymphflow. To perform SLN biopsy effectively, it is important that cancer cells are detected withhigh sensitivity in SLN connected to the tumor site. Here we present a method to visualizea high-risk area in the SLN for lymph node metastasis with a high degree of accuracy.Quantum dots (QDs), bright fluorescent nanoparticles, were endoscopically injectedinto the gastrointestinal wall of pigs, and their signal was specifically detected inthe SLN with a laparoscopic device. Single-particle imaging under a confocalmicroscope showed that the QDs were distributed heterogeneously in the SLN and thattheir distribution marked the inflow locus of afferent lymphatic vessels wherelymph node metastasis begins. Moreover, we developed a method using cellularmarker conjugated QDs that visualizes specific cells in SLNs, suggesting thatthis method can be applied for the detection of cancer cells in sentinel lymphnodes using tumor-specific-molecular conjugated QDs. These results show that ourmethod might significantly increase the detection rate of cancer metastasis in SLNs.

18F-FDG PET for retropharyngeal lymph node metastasis in oropharyngeal and hypopharyngeal cancers: impact on diagnosis and prediction analysis

Retropharyngeal lymph node (RPLN) metastasis is a poor prognosticator in oropharyngeal and hypopharyngeal cancers. The purpose of this study is to evaluate the impact of F-fluorodeoxyglucose positron emission tomography (F-FDG PET) on the diagnosis and predictor analysis of RPLN in these cancers. We enrolled patients with oropharyngeal and hypopharyngeal cancers before receiving definitive treatment. Staging was performed by F-FDG PET and conventional imaging modalities. Differences in RPLN metastasis detection rates were compared. Independent predictors of RPLN involvement were also assessed. A total of 224 patients were investigated. RPLN involvement was identified in 17% of the study patients. In 18% of the 38 patients with RPLN involvement, RPLN metastases were identified by F-FDG PET only. Only 4% of the patients with oropharyngeal cancer and RPLN metastasis were not identified without the use of F-FDG PET, compared with 46% of patients with hypopharyngeal cancer. In multivariate analysis, posterior pharyngeal wall tumor (P=0.02) or the presence of ipsilateral level V lymph node metastasis (P=0.025) were independent predictors of RPLN involvement in hypopharyngeal cancer. In oropharyngeal cancer, no factors retained their independent significance. We concluded that F-FDG PET is helpful in detecting RPLN metastasis in hypopharyngeal cancer. The presence of ipsilateral level V lymph node metastasis or tumors originating from the posterior pharyngeal wall can predict RPLN involvement in hypopharyngeal cancer and might represent an indication for elective irradiation of this nodal basin. However, regional lymph node involvement is not an independent predictor in oropharyngeal cancer. The predictor for RPLN metastasis seems to change after the introduction of PET.