Objective To investigate the correlation between CT texture analysis and synchronous distant metastasis in patients with lymph node-negative colorectal cancer. Methods The preoperative CT images of 82 patients with lymph node-negative colorectal cancer were analyzed retrospectively.There were 12 patients with simultaneous distant metastasis and 70 patients without simultaneous distant metastasis.The maximum plane of the lesion on plain scan and portal CT images was analyzed by TexRAD software.When the spatial scaling factor(SSF)was 0 and 2-6,six texture parameters were obtained,and the differences of texture parameters between the two groups were compared.The counting data were analyzed by chi-square test and the measurement data by Mann-Whitney test. Results There was a significant difference in the skewness of SSF=3 between the simultaneous distant metastasis group and the non-synchronous metastasis group on plain CT scan(
Colorectal Neoplasms/diagnostic imaging* ; Humans ; Lymph Nodes/diagnostic imaging* ; Neoplasm Metastasis ; Retrospective Studies ; Tomography, X-Ray Computed

OBJECTIVETo compare the difference in CT manifestations between primary colorectal mucinous adenocarcinoma and signet ring cell carcinoma in order to improve radiologic diagnosis.

METHODSClinicopathological data and CT findings of 109 patients with colorectal mucinous adenocarcinoma and 46 patients with primary colorectal signet-ring cell carcinoma confirmed by surgery and pathology from March 2008 to February 2015 in the Tumor Hospital of Yunnan Province were retrospectively collected. Differences in age, gender, tumor location, length and thickness of the involved intestinal wall, thickening pattern of the intestinal wall, lesion density, calcification, contrast-enhanced form, peri-intestinal invasion, occurrence of intestinal obstruction and metastasis of other organs were compared between the two groups.

RESULTSAmong 109 patients with colorectal mucinous adenocarcinoma, 68 were men and 41 were women with a mean age of (56.8±15.4) years. Among 46 patients with primary colorectal signet-ring cell carcinoma, 26 were men and 20 were women with a mean age of (42.9±15.6) years. Compared with mucinous adenocarcinoma group, signet-ring cell carcinoma group showed more concentric bowel-wall thickening[93.5%(43/46) vs. 81.6%(89/109), χ=9.19, P=0.030], higher lesion density [(42.0±3.0) Hu vs. (28.5±1.5) Hu, t=37.30, P=0.000], more marked enhancement [54.3%(25/46) vs. 12.8%(14/109), χ=35.21, P=0.000], less vast-low-density region in enhanced CT imaging[2.2%(1/46) vs. 45.0%(49/109), χ=73.31, P=0.000] and more severe peri-intestinal invasion [41.3% (19/46) vs. 17.4%(19/109), χ=10.25, P=0.006]. Calcification was found in 18.3%(20/109) of mucinous adenocarcinoma cases, but was not found in signet-ring cell carcinoma cases (χ=9.69, P=0.002). Target ring sign in contrast-enhanced scan was observed in 15.2%(7/46) of signet-ring cell carcinoma cases, while in none of mucinous adenocarcinoma cases (χ=17.37, P=0.000). There were no statistically significant differences in lesion location, length and thickness of the involved intestinal wall, occurrence of intestinal obstruction, lymph node metastasis, liver or peritoneum metastasis between two groups(all P>0.05).

CONCLUSIONSSignet-ring cell carcinoma is often found in younger patients, whose CT manifestation is characterized by the target ring sign in contrast-enhanced scan, while primary colorectal mucinous adenocarcinoma is often in older patients, whose CT manifestation is characterized by calcification in unenhanced scan and low density region in enhanced CT show.

Adenocarcinoma, Mucinous ; diagnostic imaging ; pathology ; Adult ; Age Factors ; Aged ; Calcinosis ; diagnostic imaging ; pathology ; Carcinoma, Signet Ring Cell ; diagnostic imaging ; pathology ; China ; Colorectal Neoplasms ; diagnostic imaging ; pathology ; Female ; Humans ; Male ; Middle Aged ; Neoplasm Staging ; Retrospective Studies ; Tomography, X-Ray Computed ; methods

OBJECTIVETo investigate the clinical application of 256 multi-slice spiral computed tomography angiography (MSCTA) technique in the preoperative evaluation of mesenteric angiography in order to provide a reference to vessel anatomy and dissociation in laparoscopic radical operation for colorectal carcinoma.

METHODSClinical data of 50 patients with colorectal cancer who underwent preoperative MSCTA+FDCT and laparoscopic curative operation at our hospital from October 2013 to March 2015 were collected (MSCTA group). The evaluation item was visualization of mesenteric artery, which was compared with the findings under laparoscopic surgery. Meanwhile, another 50 colorectal cancer patients undergoing laparoscopic radical operation by the same surgeon team without preoperative MSCTA examination were used as control(control group). Clinical data were compared between the two groups.

RESULTSMSCTA precisely and correctly demonstrated anatomy and variations of the mesenteric artery and relative nutrient vessel in carcinoma. The angiography reconstruction images were consistent with the visual anatomy and variation from laparoscopic findings, whose diagnostic conformity rate of 100%. As compared to control group, operative time was shorter [(195.0±23.2) minutes vs.(218.0±19.6) minutes, t=8.326, P=0.015], and blood loss was less[(168.1±18.8) ml vs. (206.5±14.3) ml, t=-19.369, P=0.002] in MSCTA group. Differences of number of harvested lymph node, postoperative complication morbidity, postoperative hospital stay and hospitalization cost were not significant between two groups(all P>0.05).

CONCLUSIONPreoperative MSCTA can demonstrate anatomy and variations of the mesenteric artery precisely and correctly, thus it is beneficial to shorten the operation time and to reduce blood loss.

Angiography ; Colorectal Neoplasms ; diagnostic imaging ; surgery ; Humans ; Image Processing, Computer-Assisted ; Laparoscopy ; Lymph Nodes ; Mesenteric Arteries ; diagnostic imaging ; Operative Time ; Tomography, Spiral Computed

Colorectal carcinoma is a common lethal disease with signs and symptoms that may be nonspecific. Computed tomography (CT) of the abdomen and pelvis with or without contrast is frequently performed for various general abdominal complaints, but unlike CT colonography, the large bowel may not be optimally prepared for evaluation. As such, careful and diligent assessment of the non-prepared colon in all CT images of the abdomen and pelvis is important, as it ensures that incidental colorectal malignancy is not missed, especially in older patients. This article gives an overview of multidetector CT imaging signs and subtle clues to aid in the diagnosis of colorectal carcinoma, as well as their pitfalls.
Colonic Polyps ; pathology ; Colonography, Computed Tomographic ; Colorectal Neoplasms ; diagnosis ; diagnostic imaging ; Diagnosis, Differential ; Humans ; Incidental Findings ; Pelvis ; diagnostic imaging ; Radiography, Abdominal ; Tomography, X-Ray Computed

OBJECTIVETo explore the value of computed tomography colonography with low radiation dose combined with the enhanced scanning in the diagnosis of colorectal carcinoma.

METHODSA total of 120 patients with clinical suspected colorectal carcinoma undergoing CT colonography and enhanced scanning were randomly divided into routine dose group and low dose group. Conventional colonoscopy and/or surgical pathology were used as the gold standard. Sensitivity, specificity and Youden's index of colorectal cancer TNM staging accuracy were calculated in two groups. The radiation dose of two groups was compared.

RESULTSFor conventional dose and low dose group, in the diagnosis of colorectal cancer (including cancer and adenoma), the sensitivity was 100% (45/45 and 44/44), specificity was 93.3%(14/15) and 87.5%(14/16), the Youden's index was 0.93 and 0.88. There were no significant differences between two groups in T, N and M staging accuracy preoperatively (P>0.05). The effective radiation dose of low dose group was significantly lower than that of conventional dose group [(15.9 ± 4.3) mSv vs. (21.4 ± 5.5) mSv, P<0.01].

CONCLUSIONLow dose CTC combined with enhanced scanning not only reduces the radiation dose of patients, but can possesses similar value of conventional dose CTC in the early diagnosis and preoperative pathological staging of colorectal cancer.

Colonography, Computed Tomographic ; Colonoscopy ; Colorectal Neoplasms ; diagnostic imaging ; Humans ; Radiation Dosage

OBJECTIVETo explore the correlation between metabolic tumour volume (MTV) and microvessel density (MVD) and blood-borne metastasis in colorectal carcinoma.

METHODSThirty-six patients with CRC conformed by pathology underwent PET-CT examination before operation. SUVmax and MTV were obtained by PET VCRA software. The blood vessels were identified with CD34 immunohistochemical staining, and the MVD was recorded. The correlation between SUVmax and MTV with histological differentiation, T stage, MVD and blood-borne metastasis was analyzed.

RESULTSThe SUVmax, MTV and MVD in patients with blood-borne metastasis were 5.15 ± 5.41, (22.99 ± 18.63) cm³ and 14.17 ± 3.63, and were 10.65 ± 3.79, (16.95 ± 11.82) cm³ and 11.27 ± 3.69, respectively, in patients with non-blood-borne metastasis. The differences of SUVmax, MTV and MVD between blood-borne metastasis and non-blood-borne metastasis patients were statistically significant (all P > 0.05). Pearson correlation analysis found that there was no linear correlation between SUVmax and MVD, and the SUVmax was not statistically significant between high and low MVD groups (t = 0.919, P = 0.364). But there was a linear correlation between MTV and MVD (r = 0.621, P = 0.000), and the MTV was statistically significant between high and low MVD groups (t = 3.567, P = 0.001). The receiver-operating characteristic curves showed that MTV could be used to predict blood-borne metastasis of CRC, and the best cutoff value for MTV was 14.975 cm³, and the sensitivity, specificity, negative predictive value and positive predictive value were 85.7%, 54.5%, 72.3% and 64.2%, respectively. There were no significant relationships between SUVmax, MTV, MVD, blood-borne metastasis and histological differentiation (P > 0.05). With the increased T stage, the MTV, MVD and the probability of blood-borne metastasis were also increased (all P < 0.05).

CONCLUSIONSThere are correlations between MTV and MVD and blood-borne metastasis in CRC. The risk of blood-borne metastasis in patients with MTV > 14.975 cm³ is higher, and needs to take more effective intervention.

Colorectal Neoplasms ; blood supply ; diagnostic imaging ; pathology ; Fluorodeoxyglucose F18 ; Humans ; Microvessels ; pathology ; Multimodal Imaging ; Neoplasm Staging ; Neoplastic Cells, Circulating ; Positron-Emission Tomography ; ROC Curve ; Radiopharmaceuticals ; Sensitivity and Specificity ; Tomography, X-Ray Computed

INTRODUCTIONThis study assessed the health screening behaviour of Singaporeans and evaluated factors associated with low uptake of screening tests.

MATERIALS AND METHODSData from the 2010 National Health Survey, which was conducted on Singapore citizens and permanent residents, was used in this analysis. Multivariate Cox regression was used to evaluate the relationship between sociodemographics and health screening behaviour for selected chronic diseases (hypertension, diabetes and hypercholesterolaemia) and cancers (cervical, breast and colorectal). National recommendations for age at which screening should be initiated and appropriate screening interval were used to define appropriate screening behaviour.

RESULTSMore respondents have had their last chronic disease screening done within the recommended time period compared to cancer screening. A total of 77.8%, 63.4% and 54.9% of the respondents had their last hypertension, diabetes and hypercholesterolaemia done within the recommended time period respectively, while less than 50% of the respondents had their cervical (45.8%), breast (32.9%) and colorectal (20.2%) cancer screenings done within the recommended time period. Respondents with higher household income or more years of education were more likely to have undergone screening within the recommended time period. Indians, who are at higher risk of chronic diseases such as diabetes and hypercholesterolaemia, were also more likely to have been screened. A total of 69.9% and 79.5% of the respondents with previously undiagnosed diabetes and hypertension had reported to have done diabetes and hypertension screenings respectively, within the recommended time period.

CONCLUSIONSociodemographic factors that could be associated with a lower uptake of screening tests include: 1) low household income, 2) low education level, and 3) Malay ethnicity. Health promotion programmes and outreach to these groups can be enhanced to further improve screening uptake.

Adult ; Aged ; Breast Neoplasms ; diagnostic imaging ; Colonoscopy ; utilization ; Colorectal Neoplasms ; diagnosis ; Diabetes Mellitus ; diagnosis ; Early Detection of Cancer ; utilization ; Female ; Health Behavior ; Humans ; Hypercholesterolemia ; diagnosis ; Hypertension ; diagnosis ; Male ; Mammography ; utilization ; Mass Screening ; utilization ; Middle Aged ; Neoplasms ; diagnosis ; Occult Blood ; Papanicolaou Test ; utilization ; Proportional Hazards Models ; Singapore ; Surveys and Questionnaires ; Uterine Cervical Neoplasms ; diagnosis ; Vaginal Smears ; utilization

BACKGROUND/AIMS: The aim of this study was to evaluate the influence of recent chemotherapy on the patterns of the maximum-standardized uptake value (M-SUV) and sensitivity of 18F-fluoro-deoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) in colorectal cancer. METHODS: We retrospectively analyzed the FDG-PET/CT of 509 patients who underwent surgery for colorectal cancer. Subgroup analysis was performed according to chemotherapy status; 401 patients were not treated with chemotherapy and 108 patients were treated with chemotherapy within 6 months prior to surgery. Pathologic analysis of the surgical specimen was used as the gold standard. RESULTS: The M-SUV was significantly lower in patients treated with chemotherapy than in those not treated with chemotherapy in pathologically confirmed same stages of disease. The difference in the sensitivity of the M-SUV according to chemotherapy status was greatest using a cutoff M-SUV value of 6.4 (p<0.001). The longest diameter of the primary tumor was the most important factor that correlated with M-SUV of the primary tumor irrespective of the chemotherapy effect (p<0.001). The M-SUV of the primary tumor was not an independent predictor of lymph node metastasis in colorectal cancer. CONCLUSIONS: The results indicate that the M-SUV of FDG-PET/CT should be interpreted in the context of concurrent chemotherapy.
Aged ; Antineoplastic Agents/*adverse effects ; Chemoradiotherapy, Adjuvant/adverse effects ; Chemotherapy, Adjuvant/adverse effects ; Colorectal Neoplasms/drug therapy/pathology/*radionuclide imaging ; Female ; Fluorodeoxyglucose F18/diagnostic use/*pharmacology ; Humans ; Male ; Neoplasm Invasiveness ; Neoplasm Metastasis ; Positron-Emission Tomography/methods ; Radiopharmaceuticals/diagnostic use/*pharmacology ; Retrospective Studies

OBJECTIVETo investigate the value of water enema (18)F-fluorodexyglucose positron emission tomography and computed tomography((18)F-FDG PET-CT) in incidental finding of hypermetabolism focus in the colon and rectum for differential diagnosis of benign or malignant lesions.

METHODSFrom June 2010 to December 2012 in our hospital, 77 patients were found incidentally with uncertain hypermetabolism focuses in the colon and rectum during PET-CT examination. Water enema (18)F-FDG PET-CT was performed to classify the lesions. According to the pathological examination and clinical follow-up, these cases were divided into malignant disease (including advanced colorectal adenoma), benign adenoma, inflammation and physiological uptake. Radioactive uptake level (SUVmax) and change of water enema imaging (retention index, RI) of hypermetabolism focus were compared between groups.

RESULTOf these 77 cases, 23 were malignant diseases, 16 benign adenoma, 7 inflammation and 31 physiological uptake. The difference of average SUVmax was not statistically significant between benign and malignant lesions as well as physiological uptake(P>0.05). But the difference of RI was statistically significant between neoplastic lesions and inflammation(P<0.05). The accuracy of water enema (18)F-FDG PET-CT in diagnosing non-neoplastic uptake was 100%, and the sensitivity, specificity and accuracy in differentiation of malignancy form benign lesions were 95.6%, 96.3%, and 96.1% respectively.

CONCLUSIONSThe incidental focal colorectal (18)F-FDG uptake in PET-CT may indicate potential colorectal malignant lesions and adenoma. Water enema can effectively differentiate the physiological uptake and predict benign lesions or malignancy in the colon and rectum colorectum with good accuracy.

Adenoma ; Colorectal Neoplasms ; diagnostic imaging ; Diagnosis, Differential ; Enema ; Fluorodeoxyglucose F18 ; Humans ; Incidental Findings ; Positron-Emission Tomography ; Radiopharmaceuticals ; Tomography, X-Ray Computed ; Water

OBJECTIVETo explore the value of comprehensive application of CT and PET/CT in differential diagnosing mucinous and non-mucinous colorectal adenocarcinoma.

METHODSCT and PET/CT image data of 37 patients with mucinous adenocarcinoma and 50 patients with non-mucinous adenocarcinoma confirmed by pathology in our hospital from January 2010 to December 2012 were analyzed retrospectively. Differences of image were compared between two methods.

RESULTSOn CT, lesion density of pre-contrast, pro-contrast phase and enhancement degree were significantly lower in mucinous adenocarcinoma than those in non-mucinous adenocarcinoma(all P<0.01). Enhancement degree of hypointense area, hypointense area proportion of total lesion, and lymphatic or distant metastasis ratio were significantly higher in mucinous adenocarcinoma than those in non-mucinous adenocarcinoma(all P<0.05). On PET/CT, maximal SUV value of mucinous adenocarcinoma was significantly lower as compared to non-mucinous adenocarcinoma[(8.64±4.34) Bq/L vs. (12.38±5.96) Bq/L, P=0.015].

CONCLUSIONSCT combined with PET/CT provides better valuable information in differential diagnosing between mucinous and non-mucinous colorectal adenocarcinoma and clinical practice.

Adenocarcinoma ; diagnostic imaging ; Adenocarcinoma, Mucinous ; diagnostic imaging ; Colorectal Neoplasms ; diagnostic imaging ; Humans ; Multimodal Imaging ; Positron-Emission Tomography ; Retrospective Studies ; Tomography, X-Ray Computed