Double contrast-enhanced ultrasonography improves diagnostic accuracy of T staging compared with multi-detector computed tomography in gastric cancer patients

BACKGROUND Gastric cancer(GC)is the most common malignant tumor and ranks third for cancer-related deaths among the worldwide.The disease poses a serious public health problem in China,ranking fifth for incidence and third for mortality.Knowledge of the invasive depth of the tumor is vital to treatment decisions.AIM To evaluate the diagnostic performance of double contrast-enhanced ultrasonography(DCEUS)for preoperative T staging in patients with GC by comparing with multi-detector computed tomography(MDCT).METHODS This single prospective study enrolled patients with GC confirmed by preoperative gastroscopy from July 2021 to March 2023.Patients underwent DCEUS,including ultrasonography(US)and intravenous contrast-enhanced ultrasonography(CEUS),and MDCT examinations for the assessment of preoperative T staging.Features of GC were identified on DCEUS and criteria developed to evaluate T staging according to the 8th edition of AJCC cancer staging manual.The diagnostic performance of DCEUS was evaluated by comparing it with that of MDCT and surgical-pathological findings were considered as the gold standard.RESULTS A total of 229 patients with GC(80 T1,33 T2,59 T3 and 57 T4)were included.Overall accuracies were 86.9%for DCEUS and 61.1%for MDCT(P<0.001).DCEUS was superior to MDCT for T1(92.5%vs 70.0%,P<0.001),T2(72.7%vs 51.5%,P=0.041),T3(86.4%vs 45.8%,P<0.001)and T4(87.7%vs 70.2%,P=0.022)staging of GC.CONCLUSION DCEUS improved the diagnostic accuracy of preoperative T staging in patients with GC compared with MDCT,and constitutes a promising imaging modality for preoperative evaluation of GC to aid individualized treatment decision-making.

Assessment of spermatogenesis in camels via seminiferous tubule staging and testosterone profiling

Objective:To investigate the successive morphological stages of spermatogenesis,hormonal regulation,and testosterone profile in dromedary camel reproduction.Methods:Testicular tissue samples were obtained from 12 dromedary bull camels aged 7 to 8 at a local abattoir.The histological assessment involved tissue processing,hematoxylin and eosin(H&E)staining,and examination under a microscope.Stereological analysis,germ cell identification,and assessment of seminiferous tubules and maturation were conducted.Testosterone assay was performed by radioimmunoassay using blood samples collected at regular intervals.Results:The study revealed 12 phases of the dromedary camel's seminiferous epithelium cycle,highlighting distinct morphological characteristics and cellular processes.Acrosomal migration,maturation,cap formation,and the Golgi-mediated synthesis of proacrosomal vesicles were also explained in dimension,as were the steps of acrosome biogenesis.Spermatids and mature sperm cells were present when spermatogenesis phases were examined.An analysis of the dimensions of seminiferous tubules revealed specific measures for diameter,area,and epithelial height about luminal characteristics.Moreover,there were noticeable variations in the serum testosterone concentrations during the study period,indicating temporal dynamics.Conclusions:This study outlines the spermatogenesis process in dromedary camels across 12 stages,emphasizing cellular dynamics and acrosomal biogenesis.It also provides seminiferous tubule measurements and observes seasonal testosterone fluctuations,offering insights into reproductive regulation and potential strategies for camel breeding conservation.

Development of a novel staging classification for Siewert Ⅱ adenocarcinoma of the esophagogastric junction after neoadjuvant chemotherapy

BACKGROUND Stage classification for Siewert Ⅱ adenocarcinoma of the esophagogastric junction(AEG)treated with neoadjuvant chemotherapy(NAC)has not been established.AIM To investigate the optimal stage classification for Siewert Ⅱ AEG with NAC.METHODS A nomogram was established based on Cox regression model that analyzed variables associated with overall survival(OS)and disease-specific survival(DSS).The nomogram performance in terms of discrimination and calibration ability was evaluated using the likelihood-ratio test,Akaike information criterion,Harrell concordance index,time-receiver operating characteristic curve,and decision curve analysis.RESULTS Data from 725 patients with Siewert type Ⅱ AEG who underwent neoadjuvant therapy and gastrectomy were obtained from the Surveillance,Epidemiology,and End Results database.Univariate and multivariate analyses revealed that sex,marital status,race,ypT stage,and ypN stage were independent prognostic factors of OS,whereas sex,race,ypT stage,and ypN stage were independent prognostic factors for DSS.These factors were incorporated into the OS and DSS nomograms.Our novel nomogram model performed better in terms of OS and DSS prediction compared to the 8th American Joint Committee of Cancer pathological staging system for esophageal and gastric cancer.Finally,a user-friendly web application was developed for clinical use.CONCLUSION The nomogram established specifically for patients with Siewert type Ⅱ AEG receiving NAC demonstrated good prognostic performance.Validation using external data is warranted before its widespread clinical application.

Localized-domains staging structure and evolution in lithiated graphite

Intercalation provides to the host materials a means for controlled variation of many physical/chemical properties and dominates the reactions in metal‐ion batteries.Of particular interest is the graphite intercalation compounds with intriguing staging structures,which however are still unclear,especially in their nanostructure and dynamic transition mechanism.Herein,the nature of the staging structure and evolution of the lithium(Li)‐intercalated graphite was revealed by cryogenic‐transmission electron microscopy and other methods at the nanoscale.The intercalated Li‐ions distribute unevenly,generating local stress and dislocations in the graphitic structure.Each staging compound is found macroscopically ordered but microscopically inhomogeneous,exhibiting a localized‐domains structural model.Our findings uncover the correlation between the long‐range ordered structure and short‐range domains,refresh the insights on the staging structure and transition of Li‐intercalated/deintercalated graphite,and provide effective ways to enhance the reaction kinetic in rechargeable batteries by defect engineering.

Is There Re-staging Surgery Necessity for Borderline Ovarian Tumors

Objective:This study assessed the necessity of surgical re-staging in women with borderline ovarian tumors(BOTs)and evaluated the impact of complete surgical staging,lymphadenectomy,and omentectomy on disease recurrence and survival.Methods:We retrospectively reviewed the medical records of patients with BOTs.A total of 901 patients were eligible for inclusion in the study,and we evaluated some of the variables and clinical/surgical characteristics of the cases.The effects of the type of surgical procedure,surgical staging,and complete or incomplete staging on recurrence were calculated.The rates of disease-free survival,overall survival,and recurrence were compared according to complete surgical staging.A Cox regression analysis was performed to identify potential prognostic factors,and survival curves were constructed using the Kaplan-Meier method.Results:The overall recurrence rate was 13.9%,and recurrence was comparable between the complete surgical staging group and the incomplete groups(P>0.05).The performance of complete surgical staging did not show an effect on long-term survival,and complete surgical staging,omentectomy,and lymphadenectomy had no effect on recurrence.In multivariate analyses,only radical surgery and adjuvant chemotherapy were risk factors for the recurrence of BOTs.Furthermore,we found that omentectomy led to a relatively low recurrence rate in patients with International Federation of Gynecology and Obstetrics(FIGO)stage>Ⅰ(P=0.022).Conclusion:Our results suggest that complete surgical staging should be considered a standard treatment for patients with advanced stage BOTs but not for those at FIGO stageⅠ.It might be safe to reduce the scope of surgical procedures in patients with early-stage BOTs.However,it is not necessary to perform re-staging operations for BOTs with a macroscopically normal extra-ovarian appearance.

Systematic review of diagnostic tools for peritoneal metastasis in gastric cancer-staging laparoscopy and its alternatives

BACKGROUND Gastric cancer is one of the leading causes of cancer burden and mortality,often resulting in peritoneal metastasis in advanced stages with negative survival outcomes.Staging laparoscopy has become standard practice for suspected cases before a definitive gastrectomy or palliation.This systematic review aims to compare the efficacy of other diagnostic modalities instead of staging laparoscopy as the alternatives are able to reduce cost and invasive staging procedures.Recently,a radiomic model based on computed tomography and positron emission tomography(PET)has also emerged as another method to predict peritoneal metastasis.AIM To determine if the efficacy of computed tomography,magnetic resonance imaging and PET is comparable with staging laparoscopy.METHODS Articles comparing computed tomography,PET,magnetic resonance imaging,and radiomic models based on computed tomography and PET to staging laparoscopies were filtered out from the Cochrane Library,EMBASE,PubMed,Web of Science,and Reference Citations Analysis(https://www.referencecitationanalysis.com/).In the search for studies comparing computed tomography(CT)to staging laparoscopy,five retrospective studies and three prospective studies were found.Similarly,five retrospective studies and two prospective studies were also included for papers comparing CT to PET scans.Only one retrospective study and one prospective study were found to be suitable for papers comparing CT to magnetic resonance imaging scans.RESULTS Staging laparoscopy outperformed computed tomography in all measured aspects,namely sensitivity,specificity,positive predictive value and negative predictive value.Magnetic resonance imaging and PET produced mixed results,with the former shown to be only marginally better than computed tomography.CT performed slightly better than PET in most measured domains,except in specificity and true negative rates.We speculate that this may be due to the limited F-fluorodeoxyglucose uptake in small peritoneal metastases and in linitis plastica.Radiomic modelling,in its current state,shows promise as an alternative for predicting peritoneal metastases.With further research,deep learning and radiomic modelling can be refined and potentially applied as a preoperative diagnostic tool to reduce the need for invasive staging laparoscopy.CONCLUSION Staging laparoscopy was superior in all measured aspects.However,associated risks and costs must be considered.Refinements in radiomic modelling are necessary to establish it as a reliable screening technique.

Application of CD34 expression combined with three-phase dynamic contrast-enhanced computed tomography scanning in preoperative staging of gastric cancer

BACKGROUND Accurate preoperative staging of gastric cancer(GC),a common malignant tumor worldwide,is critical for appropriate treatment plans and prognosis.Dynamic three-phase enhanced computed tomography(CT)scanning for preoperative staging of GC has limitations in evaluating tumor angiogenesis.CD34,a marker on vascular endothelial cell surfaces,is promising in evaluating tumor angiogenesis.We explored the value of their combination for preoperative staging of GC to improve the efficacy and prognosis of patients with GC.Medical records of 106 patients with GC treated at the First People's Hospital of Lianyungang between February 2021 and January 2023 were retrospectively studied.All patients underwent three-phase dynamic contrast-enhanced CT scanning before surgery,and CD34 was detected in gastroscopic biopsy specimens.Using surgical and pathological results as the gold standard,the diagnostic results of three-phase dynamic contrast-enhanced CT scanning at different T and N stages were analyzed,and the expression of CD34-marked microvessel density(MVD)at different T and N stages was determined.The specificity and sensitivity of three-phase dynamic contrast-enhanced CT and CD34 in T and N staging were calculated;those of the combined diagnosis of the two were evaluated in parallel.Independent factors affecting lymph node metastasis were analyzed using multiple logistic regression.RESULTS The accuracy of three-phase dynamic contrast-enhanced CT scanning in diagnosing stages T1,T2,T3 and T4 were 68.00%,75.00%,79.41%,and 73.68%,respectively,and for diagnosing stages N0,N1,N2,and N3 were 75.68%,74.07%,85.00%,and 77.27%,respectively.CD34-marked MVD expression increased with increasing T and N stages.Specificity and sensitivity of three-phase dynamic contrast-enhanced CT in T staging were 86.79%and 88.68%;for N staging,89.06%and 92.86%;for CD34 in T staging,64.15%and 88.68%;and for CD34 in N staging,84.38%and 78.57%,respectively.Specificity and sensitivity of joint diagnosis in T staging were 55.68%and 98.72%,and N staging were 75.15%and 98.47%,respectively,with the area under the curve for diagnosis improving accordingly.According to multivariate analysis,a longer tumor diameter,higher pathological T stage,lower differ-entiation degree,and higher expression of CD34-marked MVD were independent risk factors for lymph node metastasis in patients with GC.CONCLUSION With high accuracy in preoperatively determining the invasion depth and lymph node metastasis of GC,CD34 expression and three-phase dynamic contrast-enhanced CT can provide a reliable basis for surgical resection.

Progress of Imaging Histology in the Diagnosis and TNM Staging of Gastric Cancer

Gastric cancer is one of the most common malignant tumours with complex dynamic heterogeneity and aggressiveness, and the information that can be evaluated by traditional imaging is limited and subjective. With the development of machine learning, radiomics can combine medical imaging with genomics and proteomics to discover latent information, a feature that makes it a beneficial aid to assist physicians in clinical decision making and is used in all areas of gastric cancer diagnosis and treatment. In this paper, we describe the workflow of radiomics and the research progress in gastric cancer diagnosis.

Incorporation of perigastric tumor deposits into the TNM staging system for primary gastric cancer

BACKGROUND The current prognostic significance of perigastric tumor deposits(TDs)in gastric cancer(GC)remains unclear.AIM To assess the prognostic value of perigastric TDs and put forward a new TNM staging framework involving TDs for primary GC.METHODS This study retrospectively analyzed the pathological data of 6672 patients with GC who underwent gastrectomy or surgery for GC with other diseases from January 1,2012 to December 31,2017 at the Chinese PLA General Hospital.According to the presence of perigastric TDs or not,the patients were divided into TD-positive and TD-negative groups by using the method of propensity score matching.The differences between TD-positive and TD-negative patients were analyzed using binary logistic regression modeling.The Kaplan-Meier method was used to plot survival curves.Multivariate Cox regression modeling and the log-rank test were used to analyze the data.RESULTS Perigastric TDs were found to be positive in 339(5.09%)of the 6672 patients with GC,among whom 237 were men(69.91%)and 102 were women(30.09%)(2.32:1).The median age was 59 years(range,27 to 78 years).Univariate and multivariate survival analyses indicated that TD-positive GC patients had a poorer prognosis than TD-negative patients(P<0.05).The 1-,3-,and 5-year overall survival rates of GC patients with TDs were 68.3%,19.6%,and 11.2%,respectively,and these were significantly poorer than those without TDs of the same stages.There was significant variation in survival according to TD locations among the GC patients(P<0.05).A new TNM staging framework for GC was formulated according to TD location.When TDs appear in the gastric body,the original stages T1,T2,and T3 are classified as T4a with the new framework,and the original stages T4a and T4b both are classified as T4b.When TDs appear in the lesser curvature,the previous stages N0,N1,N2,and N3 now both are classified as N3.When TDs appear in the greater curvature or the distant tissue,the patient should be categorized as having M1.With the new GC staging scheme including TDs,the survival curves of patients in the lower grade TNM stage with TDs were closer to those of patients in the higher grade TNM stage without TDs.CONCLUSION TDs are a poor prognostic factor for patients with primary GC.The location of TDs is associated with the prognosis of patients with primary GC.Accordingly,we developed a new TNM staging framework involving TDs that is more appropriate for patients with primary GC.

Prognostic role of ultrasonography staging in patients with anal cancer

BACKGROUND Carcinomas of the anal canal are staged according to the size and extent of the disease;however,we propose including a novel ultrasound(US)staging system,based on depth of tumor invasion.In this study the clinical American Joint Committee on Cancer(AJCC)staging guidelines and the US classificationss in patients with anal cancer were compared.AIM To evaluate the prognostic role of the US staging system in patients with anal cancer.METHODS The data of 48 patients with anal canal squamous cells carcinoma,observed at our University Hospital between 2007 and 2017,who underwent pre-treatment assessment with pelvic magnetic resonance imaging(MRI),total body computed tomography(CT)scan and endoanal US were retrospectively reviewed.Anal canal tumors were clinically staged according to AJCC,determined by MRI by measurement of the longest tumor diameter,and CT scan.Endoanal US was performed with a high multi-frequency(9-16 MHz),360°rotational mechanical probe;US classification was based on depth of tumor penetration through the anal wall,according to Giovannini’s study.All patients were treated with definitive radiation combined with 5-fluorouracile and Mitomycin-C.After treatment patients were followed-up regularly.RESULTS At baseline there were 30 and 32 T1-2,18 and 16 T3-4,31 and 19 N+patients classified according to the clinical AJCC and US staging system respectively.After a mean follow-up of 98 months,38 patients(79.1%)are alive and 28(58.3%)are disease free.During follow up 20 patients(41.6%)experienced recurrences.After univariate analysis,American Society of Anesthesiologists(ASA)score(P=0.00000001)and US staging(P=0.009)were significantly related to disease-free survival(DFS).When overall survival and DFS functions were compared,a statistically significant difference was observed for DFS survival when the US staging was applied with respect to the clinical AJCC staging.By combining the 2 significant prognostic variables,namely the US staging with the ASA score,four risks groups with different prognoses were identified.CONCLUSION Our findings suggest that US staging may be superior to traditional clinical staging,since it is significantly associated with DFS in anal cancer patients.

Multiple genetic alterations and behavior of cellular biology in gastric cancer and other gastric mucosal lesions:H.pylori infection,histological types and staging

AIM To investigate the expression of multiplegenes and the behavior of cellular biology ingastric cancer（GC）and other gastric mucosallesions and their relations to Helicobacter pylori（H.pylori）infection,tumor staging andhistological subtypes.METHODS Three hundred and twenty-sevenspecimens of gastric mucosa obtained viaendoscopy or surgical resection,and ABCimmunohistochemical staining were used todetect the expression of p53,p16,Bcl-2 andCOX-2 proteins.H.pylori was determined byrapid urea test combined with pathologicalstaining or14C urea breath test.Cellular image analysis was performed in 66 patients withintestinal metaplasia（IM）and/or dysplasia（Dys）.In 30 of them,both cancer and theparacancerous tissues were obtained at the timeof surgery.Histological pattern,tumor staging,lymph node metastasis,grading ofdifferentiation and other clinical data werestudied in the medical records.RESULTS p16 expression of IM or Dys wassignificantly lower in positive H.pylori chronicatrophic gastritis（CAG）than those withnegative H.pylori（CAG:54.8% vs 88.0%,IM:34.4% vs 69.6%,Dys:23.8% vs 53.6%,allP【0.05）,Bcl-2 or COX-2 expression of IM orDys in positive H.pylori cases was significantlyhigher than that without H.pylori（Bcl-2:68.8%vs23.9%,90.5% vs 60.7%;COX-2:50.0% vs10.8%,61.8% vs 17.8%;all P【0.05）.Themean number of most parameters of cellularimage analysis in positive H.pylori group wassignificantly higher than that in negative H.pylori group（Ellipser:53±14,40±12μm,Area1:748±572,302±202 μm2,Area2:3050±1661,1681±1990 μm2,all P【0.05;Ellipseb:79±23,58±15 μm,Ratio1:22%±5%,13%±4%,Ratio2:79%±17%,53%±20%,all P【0.01）.There was significant correlation between Bcl-2and histologic pattern of gastric carcinoma,andbetween COX-2 and tumor staging or lymph nodemetastasis（Bcl-2:75.0% vs 16.7%;COX-2:76.0% vs 20.0%,79.2% vs 16.7%;allP【0.05）.CONCLUSION p1l6, Bcl-2, and COX-2 but not p53 gene may play a role in the early genesis/ progression of gastric carcinoma and are associated with H. pylori infection. p53 gene is relatively late event in gastric tumorigenesis and mainly relates to its progression. There is more cellular-biological behavior of malignant tumor in gastric mucosal lesions with H. pylori infection. Aberrant Bcl-2 protein expression appears to be preferentially associated with the intestinal type cancer. COX-2 seems to be related to tumor staging and lymph node metastasis.

Colorectal cancer:Current imaging methods and future perspectives for the diagnosis, staging and therapeutic response evaluation

In the last 10 years the mortality rate of colorectal cancer(CRC)has decreased by more than 20%due to the rising developments in diagnostic techniques and optimization of surgical,neoadjuvant and palliative therapies.Diagnostic methods currently used in the evaluation of CRC are heterogeneous and can vary within the countries and the institutions.This article aims to discuss in depth currently applied imaging modalities such as virtual computed tomography colonoscopy,endorectal ultrasound,computed tomography(CT)and magnetic resonance imaging(MRI)in the diagnosis of CRC.Special focus is put on the potential of recent diagnostic developments as diffusion weighted imaging MRI,MRI biomarkers(dynamic enhanced MRI),positron emission tomography with 2-(fluorine-18)-fluoro-2-deoxy-D-glucose(FDG-PET)combined with computed tomography(PET/CT)and new hepatobiliary MRI contrast agents.The precise role,advantage and disadvantages of these modalities are evaluated controversially in local staging,metastatic spread and treatment monitoring of CRC.Finally,the authors will touch upon the future perspectives in functional imaging evaluating the role of integrated FDG-PET/CT with perfusion CT,MRI spectroscopy of primary CRC and hepatic transit time analysis using contrast enhanced ultrasound and MRI in the detection of liver metastases.Validation of these newer imaging techniques may lead to significant improvements in the management of patients with colorectal cancer.

How useful is rectal endosonography in the staging of rectal cancer?

It is essential in treating rectal cancer to have adequate preoperative imaging,as accurate staging can influence the management strategy,type of resection,and candidacy for neoadjuvant therapy.In the last twenty years,endorectal ultrasound(ERUS) has become the primary method for locoregional staging of rectal cancer.ERUS is the most accurate modality for assessing local depth of invasion of rectal carcinoma into the rectal wall layers(T stage) .Lower accuracy for T2 tumors is commonly reported,which could lead to sonographic overstaging of T3 tumors following preoperative therapy.Unfortunately,ERUS is not as good for predicting nodal metastases as it is for tumor depth,which could be related to the unclear definition of nodal metastases.The use of multiple criteria might improve accuracy.Failure to evaluate nodal status could lead to inadequate surgical resection.ERUS can accurately distinguish early cancers from advanced ones,with a high detection rate of residual carcinoma in the rectal wall.ERUS is also useful for detection of local recurrence at the anastomosis site,which might require fine-needle aspiration of the tissue.Overstaging is more frequent than understaging,mostly due to inflammatory changes.Limitations of ERUS are operator and experiencedependency,limited tolerance of patients,and limited range of depth of the transducer.The ERUS technique requires a learning curve for orientation and identification of images and planes.With sufficient time and effort,quality and accuracy of the ERUS procedure could be improved.

Staging laparoscopy improves treatment decision-makingfor advanced gastric cancer

AIM To evaluate the clinical value of staging laparoscopyin treatment decision-making for advancedgastric cancer （GC）.METHODS： Clinical data of 582 patients with advancedGC were retrospectively analyzed. All patientsunderwent staging laparoscopy. The strength ofagreement between computed tomography （CT） stage,endoscopic ultrasound （EUS） stage, laparoscopic stage,and final stage were determined by weighted Kappastatistic （Kw）. The number of patients with treatmentdecision-changes was counted. A χ 2 test was used toanalyze the correlation between peritoneal metastasisor positive cytology and clinical characteristics.RESULTS： Among the 582 patients, the distributions ofpathological T classifications were T2/3 （153, 26.3%）,T4a （262, 45.0%）, and T4b （167, 28.7%）. Treatmentplans for 211 （36.3%） patients were changed after staging laparoscopy was performed. Two （10.5%） of19 patients in M1 regained the opportunity for potentialradical resection by staging laparoscopy. Unnecessarylaparotomy was avoided in 71 （12.2%） patients. Thestrength of agreement between preoperative T stageand final T stage was in almost perfect agreement （Kw= 0.838; 95% confidence interval （CI）： 0.803-0.872;P 〈 0.05） for staging laparoscopy; compared with CTand EUS, which was in fair agreement. The strengthof agreement between preoperative M stage andfinal M stage was in almost perfect agreement （Kw= 0.990; 95% CI： 0.977-1.000; P 〈 0.05） for staginglaparoscopy; compared with CT, which was in slightagreement. Multivariate analysis revealed that tumorsize （≥ 40 mm）, depth of tumor invasion （T4b）, andBorrmann type （Ⅲ or Ⅳ） were significantly correlatedwith either peritoneal metastasis or positive cytology.The best performance in diagnosing P-positive wasobtained when two or three risk factors existed.CONCLUSION： Staging laparoscopy can improvetreatment decision-making for advanced GC anddecrease unnecessary exploratory laparotomy.

Radiological diagnosis and staging of hilar cholangiocarcinoma

Hilar cholangiocarcinoma is a rare malignant tumor arising from the epithelium of the bile ducts.Surgery is still the only chance of potentially curative treatment in patients with perihilar cholangiocarcinoma.However,radical resection requires aggressive surgical strategies that should be tailored optimally according to the location,size and vascular invasion of the tumors.Accurate diagnosis and staging of these tumors is therefore critical for optimal treatment planning and for determining a prognosis.Multidetector computed tomography(MDCT),magnetic resonance imaging(MRI) and MR cholangiography are useful tools,both to diagnose and stage hilar cholangiocarcinoma.Modern imaging techniques allow accurate detection of the level of obstruction and the longitudinal and radial spread of the tumor.In addition,high-resolution MDCT and MR provide specific radiographic features to determine vascular involvement of anatomic structures,such as the hepatic artery or the portal vein,which are critical to decide the surgical strategy.Finally,radiological staging allows detection of patients with distant metastasis in the liver or peritoneum who will not benefit from a surgical approach.

Multimodal imaging evaluation in staging of rectal cancer

Rectal cancer is a common cancer and a major cause of mortality in Western countries.Accurate staging is essential for determining the optimal treatment strategies and planning appropriate surgical procedures to control rectal cancer.Endorectal ultrasonography(EUS)is suitable for assessing the extent of tumor invasion,particularly in early-stage or superficial rectal cancer cases.In advanced cases with distant metastases,computed tomography(CT)is the primary approach used to evaluate the disease.Magnetic resonance imaging(MRI)is often used to assess preoperative staging and the circumferential resection margin involvement,which assists in evaluating a patient’s risk of recurrence and their optimal therapeutic strategy.Positron emission tomography(PET)-CT may be useful in detecting occult synchronous tumors or metastases at the time of initial presentation.Restaging after neoadjuvant chemoradiotherapy(CRT)remains a challenge with all modalities because it is difficult to reliably differentiate between the tumor mass and other radiation-induced changes in the images.EUS does not appear to have a useful role in post-therapeutic response assessments.Although CT is most commonly used to evaluate treatment responses,its utility for identifying and following-up metastatic lesions is limited.Preoperative high-resolution MRI in combination with diffusion-weighted imaging,and/or PET-CT could provide valuable prognostic information for rectal cancer patients with locally advanced disease receiving preoperative CRT.Based on these results,we conclude that a combination of multimodal imaging methods should be used to precisely assess the restaging of rectal cancer following CRT.

Revisions to the Tumor,Node,Metastasis staging of lung cancer(8th edition):Rationale,radiologic findings and clinical implications

The Tumor, Node, Metastasis(TNM) staging system,adopted by the Union for International Cancer Control(UICC) and the American Joint Committee on Cancer(AJCC), has been recently revised, with the new 8^(th) edition of the staging manual being published in January 2017. This edition has few but important evidencebased changes to the TNM staging system used for lung cancer. Radiologists should be aware of the updated classification system to accurately provide staging information to oncologists and oncosurgeons. In this article, we discuss the rationale, illustrate the changes with relevance to Radiology, and review the clinical implications of the 8^(th) edition of the UICC/AJCC TNM staging system with regards to lung cancer.

New approaches to gastric cancer staging:Beyond endoscopic ultrasound,computed tomography and positron emission tomography

Currently,there is no single gold standard modality for staging of gastric cancer and several methods have been used complementarily in the each clinical situation. To make up for the shortcomings of conventional modalities such as endoscopic ultrasound,computed tomography and 18F-fluoro-2-deoxyglucose positron emission tomography,numerous attempts with new approaches have been made for gastric cancer staging. For T staging,magnifying endoscopy with narrow-band was evaluated to differentiate mucosal cancer from submucosal cancer. Single/double contrast-enhanced ultrasound and diffusion-weighted magnetic resonance imaging were also tried to improve diagnostic accuracy of gastric cancer. For intraoperative staging with sentinel node mapping,indocyanine green infrared and fluorescence imaging was introduced. In addition,to detect micrometastasis,real-time reverse transcription-polymerase chain reaction system with multiple markers was studied.Staging laparoscopy using 5-aminolevulinic acid-mediated photodynamic diagnosis and percutaneous diagnostic peritoneal lavage were also evaluated.However,most studies reporting new staging methods is preliminary and further studies for validation in clinical practice are needed.In this mini-review,we discuss new progress in gastric cancer staging.Especially,we focus on new diagnostic approach to gastric cancer staging beyond the conventional modalities and briefly review the remarkable clinical results of the studies published over the past three years.

Magnetic resonance imaging staging of nasopharyngeal carcinoma in the head and neck

Magnetic resonance imaging (MRI) is the modality of choice for staging nasopharyngeal carcinoma in the head and neck. This article will review the patterns of primary and nodal spread on MRI with reference to the latest 7th edition of the International Union Against Cancer/American Joint Committee on Cancer staging system.

Prostate cancer： diagnosis and staging

Prostate cancer represents an increasing health burden. The past 20 years, with the introduction of prostate-specific antigen （PSA）, has seen prostate cancer move increasingly from a condition that presented with locally advanced disease or metastases to one that is found upon screening. More is also known about the pathology ofpre-malignant lesions. Di- agnosis relies on trans-rectal ultrasound （TRUS） to obtain biopsies from throughout the prostate, but TRUS is not useful for staging. Imaging for staging, such as magnetic resonance imaging or computed tomography, still has a low accuracy compared with pathological specimens. Current techniques are also inaccurate in identifying lymph node and bony me- tastases. Nomograms have been developed from the PSA, Gleason score and clinical grading to help quantify the risk of extra-capsular extension in radical prostatectomy specimens. Improved clinical staging modalities are required for more reliable prediction of pathological stage and for monitoring of response to treatments.