Solitary metastases from colorectal carcinoma in the absence of hepatic or pulmonary metastases are rare. These can have a diverse imaging appearance, particularly after chemotherapy. It is important identify patients with solitary skeletal metastases, as they have a better prognosis than those with multiple skeletal or visceral metastases. We describe an unusual case of a solitary metastasis to the femur in a case of colon carcinoma that went undiagnosed and later presented with imaging features of osteogenic sarcoma.
Adult ; Bone Neoplasms/diagnosis/radiography/secondary ; Carcinoma/*diagnosis/pathology/radiography ; Colorectal Neoplasms/*diagnosis/pathology/radiography ; Female ; Femur/radiography ; Humans ; Magnetic Resonance Imaging ; Prognosis ; Tomography, X-Ray Computed

OBJECTIVE: We wanted to evaluate the usefulness of the computer-aided detection (CAD) system for detecting pulmonary nodules in real clinical practice by using the CT images. MATERIALS AND METHODS: Our Institutional Review Board approved our retrospective study with a waiver of informed consent. This study included 166 CT examinations that were performed for the evaluation of pulmonary metastasis in 166 patients with colorectal cancer. All the CT examinations were interpreted by radiologists and they were also evaluated by the CAD system. All the nodules detected by the CAD system were evaluated with regard to whether or not they were true nodules, and they were classified into micronodules (MN, diameter < 4 mm) and significant nodules (SN, 4 < or = diameter < or = 10 mm). The radiologic reports and CAD results were compared. RESULTS: The CAD system helped detect 426 nodules; 115 (27%) of the 426 nodules were classified as true nodules and 35 (30%) of the 115 nodules were SNs, and 83 (72%) of the 115 were not mentioned in the radiologists' reports and three (4%) of the 83 nodules were non-calcified SNs. One of three non-calcified SNs was confirmed as a metastatic nodule. According to the radiologists' reports, 60 true nodules were detected, and 28 of the 60 were not detected by the CAD system. CONCLUSION: Although the CAD system missed many SNs that are detected by radiologists, it helps detect additional nodules that are missed by the radiologists in real clinical practice. Therefore, the CAD system can be useful to support a radiologist's detection performance.
Colorectal Neoplasms/*pathology ; *Diagnosis, Computer-Assisted ; Female ; Humans ; Lung Neoplasms/*radiography/secondary ; Male ; Middle Aged ; Retrospective Studies ; Solitary Pulmonary Nodule/*radiography/secondary ; *Tomography, X-Ray Computed

Contrast-enhanced computed tomography colonography (CE-CTC) is a useful guide for the laparoscopic surgeon to avoid incorrectly removing the colonic segment and the failure to diagnose of synchronous colonic and extra-colonic lesions. Lymph node dissection and vessel ligation under a laparoscopic approach can be time-consuming and can damage vessels and organs. Moreover, mesenteric vessels have extreme variations in terms of their courses and numbers. We describe the benefit of using an abdominal vascular map created by CE-CTC in laparoscopic colorectal surgery candidates. We describe patients with different diseases (colorectal cancer, diverticular disease, and inflammatory bowel disease) who underwent CE-CTC just prior to laparoscopic surgery.
Adult ; Aged ; Colectomy/*methods ; Colon/blood supply/pathology/radiography ; Colonography, Computed Tomographic/*methods ; Colorectal Neoplasms/pathology/*radiography/*surgery ; Contrast Media ; Female ; Humans ; Laparoscopy/*methods ; Lymph Node Excision/methods ; Male ; Middle Aged ; Neoplasm Staging/methods

PURPOSE: We sought to evaluate the clinical usefulness of CT colonography (CTC) after incomplete conventional colonoscopy (CC) for occlusive colorectal cancer (CRC) according to the tumor location. MATERIALS AND METHODS: Seventy-five patients with occlusive CRC underwent subsequent CTC immediately after incomplete CC. Fifty-nine patients had distal CRC and 16 had proximal colon cancer. Experienced radiologists prospectively analyzed the location, length, and TNM staging of the main tumor. The colorectal polyps in the remaining colorectum and additional extraluminal findings were also recorded. Sixty-seven patients underwent colorectal resection. We retrospectively analyzed the surgical outcome and correlated CTC and CC findings. RESULTS: The overall accuracies of tumor staging were: T staging, 86%; N staging (nodal positivity), 70% (80%); and intra-abdominal M staging, 94%. Additional colonic polyps were found in 23 patients. Six synchronous carcinomas were detected (9%); three in the proximal colon and three in the distal colon of occlusion. Clinically significant localization errors at CC were noted in 8 patients (12%, 5 proximal colon cancers and 3 distal CRCs) and were corrected by CTC. After CTC, the surgeons modified the initial surgical plan in 11 cases (16%). CONCLUSION: In occlusive CRC, CTC is not only useful in the evaluation of the proximal bowel, but can also provide surgeons with accurate information about staging and tumor localization. CTC is recommended when endoscopists encounter occlusive CRC, regardless of tumor location.
Adult ; Aged ; Aged, 80 and over ; Colonography, Computed Tomographic/*methods ; Colonoscopy/*methods ; Colorectal Neoplasms/pathology/radiography/*surgery ; Female ; Humans ; Male ; Middle Aged ; Neoplasm Staging ; Reproducibility of Results

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

BACKGROUNDThe continual and rapid development of techniques which are used for diagnosis and treatment makes management of colorectal cancer more difficult depending on single discipline. Colorectal cancer multidisciplinary team (MDT) working model is recommended by UK and other countries, but there is little information on the impact of MDT working on management of colorectal cancer in China. The aim of this study was to assess the effect on management of colorectal cancer after the inception of an MDT.

METHODSA total of 595 consecutive colorectal cancer patients were referred to the Department of Gastroenterological Surgery, the pre-MDT cohort include 297 patients, recruited from January 1999 to November 2002, and the MDT cohort had 298 patients enrolled from December 2002 to September 2006. Information recorded included: TNM stage from histological reports, degree of differentiation, the number of examined lymph nodes and CT TNM staging performed or not, and its accuracy, including local and distant recurrence.

RESULTSThe number of examined lymph nodes and the accuracy of TNM staging by CT in the MDT group were significantly more than those in pre-MDT group. CT TNM staging was more accurate in the MDT group compared to the pre-MDT group (P = 0.044). The rate of tumor recurrence in the MDT group was lower than pre-MDT group (log-rank test, P < 0.001). Multivariate analysis revealed that age (P = 0.001), management after inception of the MDT (P = 0.002), degree of differentiation (P = 0.003), number of examined lymph nodes (P = 0.002), and TNM stage (P = 0.000) were important factors that independently influence overall survival.

CONCLUSIONSThe inception of MDT working improved the diagnostic accuracy and overall survival of colorectal cancer patients. MDT working promoted communication and cooperation between disciplines and ensured high-quality diagnosis, evidence-based decision making, and optimal treatment planning.

Aged ; Colorectal Neoplasms ; diagnostic imaging ; pathology ; surgery ; Disease Management ; Female ; Humans ; Interdisciplinary Communication ; Male ; Middle Aged ; Neoplasm Staging ; Radiography ; Treatment Outcome

Basaloid squamous cell carcinoma is a rare and aggressive variant of squamous cell carcinoma, which mostly occurs in the upper aerodigestive tracts. Basaloid squamous cell carcinoma also typically arises in the anal canal, but is extremely rare in the lower gastrointestinal tract. A 70-year-old man presented with loose stool and intermittent hematochezia 2 months ago. Colonoscopy showed an ulceroinfiltrative mass on the rectosigmoid colon from 16 cm to 18 cm above the anal verge. Conventional colonoscope could not pass through the lesion but it was possible with pediatric colonoscope. Abdominal CT scan showed 1.6 cm sized wall thickening with circumferential luminal narrowing in the rectosigmoid colon and multiple ill-defined low density masses in both lobes of the liver. Therefore, colon cancer with liver metastasis was suspected. However, basaloid cells were noted on histologic examination, and they were weakly positive for synaptophysin on immunohistochemical study. After palliative lower anterior resection, histologic examination of the resected specimen revealed basaloid differentiation with keratin pearls, and tumor cells were positively stained with high molecular weighted cytokeratin (34BE12) and CK 5/6. Thus, the patient was finally diagnosed with basaloid squamous cell carcinoma of rectosigmoid colon with distant metastases.
Aged ; Carcinoma, Squamous Cell/*diagnosis/pathology/surgery ; Colonoscopy ; Colorectal Neoplasms/*diagnosis/pathology/surgery ; Humans ; Immunohistochemistry ; Keratins/metabolism ; Liver Neoplasms/radiography/secondary ; Lung Neoplasms/radionuclide imaging/secondary ; Male ; Positron-Emission Tomography ; Synaptophysin/metabolism ; Tomography, X-Ray Computed

Colorectal cancer is the second most common cancer in males and the fourth most common in females in Korea. Since the most of colorectal cancer occur through the prolonged transformation of adenomas into carcinomas, early detection and removal of colorectal adenomas are one of the most effective methods to prevent colorectal cancer. Considering the increasing incidence of colorectal cancer and polyps in Korea, it is very important to establish Korean guideline for colorectal cancer screening and polyp detection. Korean Multi-Society Take Force developed the guidelines with evidence-based methods. Parts of the statements drawn by systematic reviews and meta-analyses. Herein we discussed the epidemiology of colorectal cancers and adenomas in Korea, optimal screening methods for colorectal cancer, and detection for adenomas including fecal occult blood tests, radiologic tests, and endoscopic examinations.
Adenoma/*diagnosis/epidemiology/radiography ; Age Factors ; Colonic Polyps/pathology ; Colonoscopy ; Colorectal Neoplasms/*diagnosis/epidemiology/radiography ; Databases, Factual ; Early Detection of Cancer ; Female ; Humans ; Immunohistochemistry ; Male ; Occult Blood ; Republic of Korea ; Tomography, X-Ray Computed

OBJECTIVE: The purpose of this study was to prospectively compare pre-operative computed tomography (CT) perfusion parameters with tumor grade from colorectal adenocarcinoma (CRC) and to correlate pre-operative CT perfusion parameters with microvessel density (MVD) to evaluate angiogenesis in CRC. MATERIALS AND METHODS: Pre-operative perfusion CTs were performed with a 64-channel multidetector row CT in 27 patients (17 women and 10 men; age range 32-82 years) who were diagnosed with CRC involving the sigmoid and rectum between August 2006 and November 2007. All patients underwent surgery without pre-operative chemotherapy or radiation therapy. Dynamic perfusion CTs were performed for 65 seconds after intravenous injection of contrast medium (100 mL, 300 mg of iodine per mL, 5 mL/sec). Before surgery, blood flow (BF), blood volume, mean transit time (MTT), and permeability-surface area product were measured in the tumor. After surgery, one gastrointestinal pathologist evaluated tumor grade and performed immunohistochemical staining using CD 34 to determine MVD in each tumor. The Kruskal-Wallis test was used to compare CT perfusion parameters with tumor grade, and Pearson's correlation analysis was used to correlate CT perfusion parameters with MVD. RESULTS: In 27 patients with CRC, tumor grading was as follows: well differentiated (n = 8); moderately differentiated (n = 15); and poorly differentiated (n = 4). BF was higher in moderately differentiated CRC than well differentiated and poorly differentiated CRCs (p = 0.14). MTT was shorter in moderately differentiated than well differentiated and poorly differentiated CRCs (p = 0.039). The MVD was greater in poorly differentiated than well differentiated and moderately differentiated CRCs (p = 0.034). There was no significant correlation between other perfusion parameters and tumor grade. There was no significant correlation between CT perfusion parameters and MVD. CONCLUSION: BF and MTT measurement by perfusion CT is effective in predicting moderately differentiated CRCs. However, perfusion CT is limited in distinguishing well differentiated and poorly differentiated CRCs. Pre-operative perfusion CT does not reflect the MVD of CRCs.
Adenocarcinoma/pathology/*radiography ; Adult ; Aged ; Aged, 80 and over ; Colorectal Neoplasms/pathology/*radiography ; Contrast Media/diagnostic use ; Female ; Humans ; Iohexol/analogs & derivatives/diagnostic use ; Male ; Microcirculation ; Middle Aged ; Neoplasm Grading ; Neovascularization, Pathologic/*radiography ; Prospective Studies ; Statistics, Nonparametric ; Tomography, X-Ray Computed/*methods

We report here two cases of foreign body granulomas that arose from the pelvic wall and liver, respectively, and simulated recurrent colorectal carcinomas in patients with a history of surgery. On contrast-enhanced CT and MR images, a pelvic wall mass appeared as a well-enhancing mass that had invaded the distal ureter, resulting in the development of hydronephrosis. In addition, a liver mass had a hypointense rim that corresponded to the fibrous wall on a T2-weighted MR image, and showed persistent peripheral enhancement that corresponded to the granulation tissues and fibrous wall on dynamic MR images. These lesions also displayed very intense homogeneous FDG uptake on PET/CT.
Adult ; Aged ; Colorectal Neoplasms/pathology/*surgery ; Contrast Media/diagnostic use ; Diagnosis, Differential ; Fluorodeoxyglucose F18/diagnostic use ; Granuloma, Foreign-Body/complications/*diagnosis ; Humans ; Hydronephrosis/etiology ; Image Enhancement/methods ; Liver/pathology/radionuclide imaging ; Liver Neoplasms/*diagnosis/secondary ; Magnetic Resonance Imaging ; Male ; Pelvic Neoplasms/*diagnosis/secondary ; Pelvis/pathology/radiography ; Positron-Emission Tomography ; Radiopharmaceuticals/diagnostic use ; Tomography, X-Ray Computed