Preoperative local staging of colorectal cancer patients with MDCT.

Abstract

To evaluate tumor invasion (T staging) and lymph node metastasis (N staging) of colorectal cancer preoperatively by using multi-detector computerized tomography (MDCT) and to compare with the histopathological findings.
MDCT scan was performed for 73 patients with pathological proven colorectal carcinoma. One radiologist prospectively evaluated the depth of tumor invasion (T staging) and regional lymph node involvement (N staging). The MDCT assessment was then compared with the histopathological findings for accuracy, sensitivity and specificity.
In this study, the best accuracy results had been acquired for T1 and T2 tumors as 90.4% and 73.9%, respectively. For both histopathologically staged N0 and N1 patients, the accuracy results were 61.6%. The distant metastases were not detected in this study.
Our study results showed that the MDCT may be useful in the preoperative assessment for the T and N staging in colorectal carcinoma.

Full text

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COLORECTAL
Οriginal Paper
Preoperative Local Staging of Colorectal
Cancer Patients with MDCT
Mustafa Duman1, Sukru Tas1, Eren Ali Mecit1, Erdal Polat1, Ugur Duman2,
Betul Ayca Kurtulus3, Hayrettin Varolgunes1 and Erdal Birol Bostanci1
1Department of Gastrointestinal Surgery and 3Department of Radiology,
Kartal Kosuyolu Training and Research Hospital, Istanbul, Turkey
2Department of General Surgery, Bursa Sevket Yilmaz Training and Research Hospital, Bursa, Turkey
Corresponding author: Ugur Duman, MD, Bursa Sevket Yilmaz Training and Research Hospital, Department of General
Surgery, Bursa, Turkey; Tel.: +90-224-2955000, Fax: +90-224-2944499; E-mail: drugurduman@yahoo.com
ABSTRACT
INTRODUCTION
Colorectal cancer is the third common malignancy
worldwide and one of the common causes of cancer re-
lated death (1,2). Preoperative evaluation of the extent
of colorectal carcinoma spread indicates the expected
prognosis and also assists management (3). The depth
of bowel wall invasion, presence of lymph node metas-
tases and distant metastases are the major factors that
affect the prognosis of the patient (4). Accurate staging
of colorectal cancer is important to provide the optimal
treatment strategy. Despite preoperative evaluation and
staging of colorectal cancer patient is difficult, comput-
erized tomography (CT) scanning has been very often
used in preoperative staging of colorectal cancer as a
non-invasive instrument with the development of high
resolution scanners, technical refinements in obtaining
better quality as a result. CT is an excellent imaging tool
for screening the distant metastases (5-7). Convention-
al colonoscopy is known to be the gold standard proce-
dure for screening the colon, but does not provide infor-
mation about the depth of the tumor invasion in the wall
of colon, lymph node involvement and distant metasta-
ses (8-10). Advances in CT technologies have increased
interest in the potential role of multi-detector comput-
erized tomography (MDCT) for detection and staging of
colorectal cancer (11). CT is the basic imaging method
of choice for the preoperative staging colorectal carcino-
mas at our clinic. For this instance, the aim of this study
is to determine the accuracy of standard protocol MDCT
in the evaluation of local tumor (T) staging and regional
lymph node (N) status in colorectal carcinomas.
METHODOLOGY
This study had been approved by local ethics commit-
tee of human studies and we got written informed con-
sent from all patients included in the study.
Between August 2007 and November 2010, seventy-
three consecutive patients (34 men with an age range
of 30-79 years and mean age of 61.7 years; 39 women
with an age range of 35-83 years and mean age of 54.38
years) with biopsy proved colorectal carcinoma were
prospectively included in this study. Among the 73 pa-
tients who had a prior colonoscopy, 24 had incomplete
application due to inability to pass a distal stricture. All
patients were operated within two weeks after CT ex-
amination.
An MDCT (Toshiba Aquilion 64™, Toshiba Medical
Systems Corp., Tokyo, Japan) scanner was used for this
study. All patients were fasted for at least 10 hours be-
fore MDCT scan and given oral colon cleaning prepara-
tion 12 hours prior to MDCT examination. Oral and in-
travenous contrasts were used in all patients. One thou-
sand milliliters of 3% diluted contrast agent solution
was given orally 60 minutes before imaging. 120mL in-
travenous non-ionic contrast agent (Ultravist®, 370mg
iodine/mL; Schering, Berlin, Germany) was adminis-
tered slowly (3mL/sec.) during the MDCT examination.
Contrast material is contraindicated in patients who
were not included in study. CT acquisitions were per-
formed in the arterial phase (start-delay of 25 seconds)
and in the venous phase (start-delay of 70 seconds). A
section of 0.5mm width was performed. MDCT exami-
nation included from the domes of the diaphragm to the
symphysis pubis. Rectal contrast material or air insuffla-
tions were not the process of CT in patients.
One radiologist who had 6 years of experience in ab-
dominal CT evaluated the images on the workstation by
using soft tissue window settings before surgery in a
blind fashion to colonoscopy results. For the location of
each lesion, the large intestine was divided into eight an-
atomic segments: caecum, ascending colon, hepatic flex-
ure, transverse colon, splenic flexure, descending colon,
Background/Aims: To evaluate tumor invasion (T
staging) and lymph node metastasis (N staging) of
colorectal cancer preoperatively by using multi-de-
tector computerized tomography (MDCT) and to com-
pare with the histopathological findings. Methodolo-
gy: MDCT scan was performed for 73 patients with
pathological proven colorectal carcinoma. One radiol-
ogist prospectively evaluated the depth of tumor inva-
sion (T staging) and regional lymph node involvement
(N staging). The MDCT assessment was then compared
with the histopathological findings for accuracy, sen-
sitivity and specificity. Results: In this study, the best
accuracy results had been acquired for T1 and T2 tu-
mors as 90.4% and 73.9%, respectively. For both histo-
pathologically staged N0 and N1 patients, the accuracy
results were 61.6%. The distant metastases were not
detected in this study. Conclusions: Our study results
showed that the MDCT may be useful in the preoper-
ative assessment for the T and N staging in colorectal
carcinoma.
Key Words:
Colorectal cancer;
MDCT; Preopera-
tive staging.
Abbreviations:
Multidetector
Computed Tomog-
raphy (MDCT);
Computed Tomog-
raphy (CT).
Hepato-Gastroenterology 2012; 59:1108-1112 doi 10.5754/hge11869
© H.G.E. Update Medical Publishing S.A., Athens

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Hepato-Gastroenterology 59 (2012)Preoperative Staging of Colorectal Cancer
sigmoid colon and rectum. All patients with colorectal
carcinoma were staged on MDCT according to the mod-
ified TN classification. Modified CT criteria were adapt-
ed from Burton et al. (5) and Hennedige et al. (6). The
reader identified the location of the cancer, extent of
local invasion, lymph node spread and adjacent organ
involvement (Tables 1 and 2). The MDCT staging cri-
teria had been used for local tumor spread and lymph
node involvement (5,6). The radiological assessment
was then compared with the surgical and histopatho-
logical findings. Pathological staging was performed ac-
cording to the tumor, node, metastasis (TNM) classifica-
tion described by the American Joint Committee on Can-
cer (AJCC) for colorectal carcinoma (11). Tomographic T
and N staging data were recorded prospectively in pa-
tients and accuracies were evaluated for postoperative
histopathological T and N staging. Abdominal wall and
spread to adjacent organs were evaluated in operation.
Stage values of T and N were evaluated according to the
localization of the tumor in colon.
Statistical analysis
Sensitivity, specificity, accuracy were calculated for T
and N staging from MDCT image results. Differences in
accuracy for N and T staging and also differences in ac-
curacy for the locations of T and N staging were assessed
by χ2 and related-samples marginal homogenity tests.
SPSS 19.0 was used for statistical tests and statistical
significance was identified at a confidence level of 5%.
RESULTS
Seventy three patients were enrolled in the study (39
females and 34 males). According to localization, 21 tu-
mors were localized in the right colon ((caecum (n=10),
ascending colon (n=5), hepatic flexure (n=2) and trans-
verse colon (n=4)), 32 tumors were localized in the left
colon (splenic flexure (n=5), descending colon (n=2),
sigmoid colon (n=25)) and 20 tumors were localized in
rectum.
At histopathological examination, 1 of 73 (1.6%) tu-
mors was staged as T1, 25 of 73 tumors (34.2%) were
staged as T2, 41 of 73 tumors (56.1%) were staged as
T3 and 6 of 73 tumors (8.2%) were staged as T4. MDCT
correctly staged 1 of 1 patient with T1 (100%). On histo-
pathology, 25 patients were staged as T2. MDCT correct-
ly staged 22 of 25 (88%) patients with T2 disease. Two
patients were understaged and one patient was over-
staged as T3 on MDCT. MDCT correctly staged 22 of 41
(53.6%) with T3. Seventeen patients were understaged
and two patients overstaged on MDCT. There were six
patients with T4 stage on histopathology; MDCT cor-
rectly staged 0 of 6 (0%) patients with T4 stage. Six pa-
tients were understaged as T2 or T3 stage on MDCT.
On histopathological examination, 36 of 73 (49.3%)
cancers were staged as N0, 23 of 73 (31.5%) cancers
were staged as N1, 8 of 73 (10.9%) cancers were staged
as N2 and 6 of 73 (8.2%) cancers were staged as N3. On
histopathology 36 patients were staged N0, MDCT cor-
rectly staged of 22 of 36 (61.1%) patients with N0 stage.
Fourteen patients were overstaged as N1-N2 disease.
MDCT correctly staged 12 of 23 (52.1%) patients with
N1 disease. Nine patients were understaged as N0 dis-
ease and two patients overstaged as N2. MDCT correct-
ly staged 1 of 8 (12.5%) patients with N2 disease. Four
patients were understaged as N0 disease and three pa-
tients were understaged as N1 disease. MDCT correctly
staged 1 of 6 (16.6%) patients with N3 stage. Three pa-
tients were understaged as N1 and two patients were
understaged as N0 stage.
MDCT for the assessment of all phases of the T and N
stages were measured separately for the accuracy, sensi-
tivity, specificity and positive predictive value, negative
predictive value (Table 3).
The distribution of CT and histopathological T stages
which were from the same patients were compared us-
ing χ2 and related samples marginal homogeneity tests.
It was found that there was a statistically significant dif-
ference between CT and histopathological T stages of
the same patients (χ2=30.75, p=0.00 (p<0.05)). T3 and
T4 stages were observed different than expected (Fig-
ure 1). Related samples homogeneity test result was
56.00 (p=0.000 (p<0.05)) and it is shown that T stages
are not distributed homogeneously in CT and histopath-
ological findings.
The distribution of CT and histopathological N stages
from the same patients were compared using χ2 and re-
lated samples marginal homogeneity tests. It was found
that there were no statistically significant differences
between CT and histopathological N stages of the same
patients (χ2=16.51, p=0.057 (p>0.05)) (Figure 2). Relat-
ed samples homogeneity test result was 29.00 (p=0.258
Stage MDCT criteria
T1
Intraluminal projection of a colonic lesion without
any visible distortion of the wall layers.
T2
Asymmetrical thickening projecting intraluminally.
Smooth preservation of muscle coat and clear
adjacent pericolic fat.
Smooth and nodular extension of a discrete mass
and disruption of the muscle coat and extension
into pericolic fat.
Nodular penetration through the peritonealised
areas of the muscle coat. Advancing edge of tumour
penetrating the adjacent organs.
T3
T4
TABLE 1. MDCT staging criteria for tumor staging. Modified
from Hennedige et al. (6) and Burton et al. (5).
StageMDCT criteria
N0
No lymph node >0.5cm and no abnormal
clustering.
N1
1-3 lymph node >0.5cm, or abnormal clustering
of 3 more normal- sized lymph nodes.
N2
N3
3-6 lymph nodes >0.5cm.
More than 6 lymph nodes >0.5cm.
TABLE 2. MDCT staging criteria for nodal staging.
Modified from Hennedige et al. (6), Burton et al. (5)
and Dighe et al. (15).
Final
StageSensitivity Specificity
T1 100
T288
T353.65
T40
N061.1
N152.17
N212.5
N316.6
Positive
predictive value
12.5
57.89
88
0
61.11
41.37
16.66
100
Negative
predictive valueAccuracy
100
91.42
60.41
91.54
62.16
75
89.55
93.05
90.27
66.7
90.6
97
62.1
66
90.7
100
90.41
73.97
69.86
2.73
61.64
61.64
83.56
93.15
TABLE 3. MDCT assessment of all phases of the T and N stages.

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Hepato-Gastroenterology 59 (2012)
(p>0.05)), and it was shown that N stages were distrib-
uted homogeneously in CT and histopathological find-
ings.
Colon tumors were classified according to localiza-
tion in colon segment. T stages were found correctly by
MDCT as follows: for right colon 15 of 21 (71.42%), for
left colon 20 of 32 (62.5%), for rectum 10 of 20 (50%).
N stages were found correctly by MDCT as follows: for
right colon 11 of 21 (52.38%), for left colon 15 of 32
(46.87%) and for rectum 10 of 20 (50%). There was no
significant difference between data for T and N stages
according to localization of the tumors (p>0.05).
DISCUSSION
Accurate preoperative evaluation of the local staging
of the colorectal cancer is required to predict prognosis
and to select most appropriate management. There is no
guideline clearly stating an optimal strategy for preoper-
ative imaging (11,12). Colonoscopy and barium contrast
radiography are the conventional gold standard methods
for detecting and diagnosing colorectal cancers. Howev-
er, total colonoscopy can not be performed in cases with
obstructing colonic lesions and colonoscopy can evaluate
the entire colon successfully in only 60-90% of patients.
It has been demonstrated that the long-term survival rate
increases when a full colonic examination is performed
before surgery (5,8-10,13). Colonoscopy and barium en-
ema do not permit a precise preoperative prediction of tu-
mor spread into adjacent organs, surrounding tissue and
lymph nodes. CT is widely used for preoperative staging
of colorectal cancer but there is no concensus on its use
(3,9,14).
CT is nowadays the standard modality for staging
colorectal cancers before curative surgical resection. Re-
cently in rectal cancers, preoperative identification of
poor prognostic factors enables safe administration of
neoadjuvant therapies. Similar to rectal cancers, preop-
erative neoadjuvant strategies colonic cancers will be re-
liant on the staging accuracy of CT (15,16). Preoperative
neoadjuvant therapy can provide down staging of tumors
in patients with high risk of poor prognosis. CT has shown
potential not only as a staging tool but also in predicting
prognosis (17). Therefore, the main objective of this study
was to evaluate the overall diagnostic accuracy of MDCT
in T and N staging of colorectal neoplasms.
Advances in CT technology have raised interest in the
potential role of CT for detecting and staging of colorec-
tal cancers. With the development of MDCT thin section
images, faster scan acquisitions, improved resolution and
multi-planar reconstruction images have shown better
accuracy in T and N staging (4,14,18). MDCT has fewer
motion artefacts due to either voluntary or involuntary
movements than single row CT (19). In this study we pre-
ferred to use MDCT as the diagnostic tool of choice to eval-
uate accuracy.
In our experience, the best sensitivity and accura-
cy values had been acquired for T1, T2 and T3 stages. T
staging accuracy had been found as 90.4% for T1, 73.97%
for T2 and 69.86% for T3. The sensitivities according to
T stages had been found as 100% for T1, 88% for T2 and
53.6 for T3. According to previous reports the overall ac-
curacy of CT in T staging of colorectal cancer ranges be-
tween 41% and 82%. The wide range of accuracy rates
depends on various CT technologies used to evaluate T
stages (20-23). Accuracy rates for T staging with MDCT
were reported to be improved when axial and multi-
planar reconstruction images were evaluated in combi-
M Duman, S Tas, EA Mecit, et al.
FIGURE 1.
Distribution
of CT and
histopathological
T stages. (CT:
Multidetector
Computerized
Tomography; P:
Histopathology;
p<0.05).
FIGURE 4.
Computerized
tomography
in a 56 year
old woman
ascending colon
cancer found to
be of T3 stage.
Histopathology
confirmed T3
stage.
FIGURE 3.
Computerized to-
mography in a 72
year old woman.
This rectal can-
cer found to be
of T2 stage. His-
topathology con-
firmed T2 stage.
FIGURE 2.
Distribution
of CT and
histopathological
N stages. (CT:
Multidetector
Computerized
Tomography; P:
Histopathology;
p>0.05).

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Hepato-Gastroenterology 59 (2012)
nation. Small strands of tumor tissue in pericolic fat on
CT images give clues in differentiating T2 from T3 stage.
These strands indicate tumoral involvement in the peri-
colic fat or serosa. Fibrosis, inflammation or congestive
changes may also result in these strand images (4,18,24).
Peritumoral reaction consisting of fibrosis and inflamma-
tion is an important cause of overstaging (25,26). Even
with the improved spatial resolution of MDCT, it is diffi-
cult to differentiate bowel wall layers as conventional sin-
gle row CT (27).
The sensitivity of CT detection depends mainly on the
size of the colorectal tumor and quality of the CT examina-
tion. Conventional CT has undergone significant changes
with the development of MDCT. The prognosis of colorec-
tal cancer is directly related to extent of colorectal wall in-
vasion, lymph node involvement and distant metastases
(28-31). In this study, analysis of the data makes a sugges-
tion that MDCT may correctly stage two parameters, lo-
cal invasion and lymph node metastasis. Despite the fre-
quent use of CT in preoperative evaluation of disseminat-
ed disease in rectal cancer, the role of the CT in local stag-
ing is limited with reported accuracies ranging from 33%
to 82% for T stage (31-33). In our study, MDCT showed an
accuracy of 75% for T1 stage, 70% for T2 stage and 60%
for T3 stage in the assessment of rectal cancer patients. In
the assessment of colon cancer patients, MDCT showed
an accuracy of 96.2% for T1 stage, 75.4 % for T2 stage
and 73.5% for T3 stage (Figures 3 and 4). No patient was
evaluated as T4 either for rectal cancer or colon cancer by
MDCT. It is reported that CT is not enough to detect mi-
croscopic extratumoral extension into the fat surround-
ing the colon and rectum and this situation results in un-
derstaging. Higher soft tissue contrast resolution makes
magnetic resonance imaging more suitable than CT for
evaluating local extent of disease in the pelvis especially
for rectal cancer patients (34).
Intwo recent meta-analyses of 130 and 78 stud-
ies, the comparison of the staging of the colorectal can-
cer using preoperative CT to histopathological examina-
tion have shown that MDCT has the potential to make a
considerable impact in improving the accuracy of stag-
ing of colorectal cancer. According to these analyses, the
main limitation of CT is the inability to accurately iden-
tify malignant nodes. The most impressive results have
been demonstrated by the studies that have utilized sec-
tions thicknesses of 5mm or less. Also these analyses have
shown that preoperative staging of colorectal cancer us-
ing MDCT is highly accurate and safe. Despite the improve-
ments in CT technology, there is already a wide variation
(22-73%) in accuracy for N staging in preoperative eval-
uation of rectal cancer patients with CT (15,16,31,35). In
our study, MDCT showed an accuracy of 75% for N0 stage,
60% for N1 stage, 85% for N2 stage and 80% N3 stage in
the assessment of rectal cancer patients. MDCT showed
an accuracy of 56.6% for N0 stage, 62.6 for N1 stage, 83.1
% for N2 stage and 98.1% N3 stage in the assessment of
colon cancer patients (Figures 5 and 6). There is a lack
of reliable CT criteria for metastatic lymph nodes. Efforts
have been made to identify CT findings indicating metas-
tasis based on analysis of morphologic features. On the
other hand, these efforts are inaccurate to diagnose nor-
mal sized nodes with microscopic tumor involvement or
enlarged benign reactive nodes. Changing the size crite-
ria towards larger or smaller cut-off values does not solve
the conflict in diagnosis because this is the intrinsic limi-
tation of CT for N staging (34,36).
Mostly in practice, CT is evaluated by a single radiol-
ogist. Therefore one radiologist evaluated the MDCT in
our study and the accuracy rate for staging was within
the range reported by other studies previously. Most er-
rors in this study resulted from inaccurate evaluation of
T4 stage, N2 and N3 stage.
In conclusion, our results suggest that the preoper-
ative staging of colorectal cancer using MDCT has good
accuracy in the prediction of T stage (especially T1, T2
and T3 stage) and good accuracy for N staging. Although
there are internal limitations in detecting microscopic in-
vasions, MDCT is a simple and useful technique for either
detecting macroscopic local invasion or whole colon ex-
amination especially in obstructing lesions. MDCT can
identify synchronous carcinomas and/or coexisting po-
lips (37). Advances in imaging technology will increase
the accuracy and usefulness of CT.
Preoperative Staging of Colorectal Cancer
FIGURE 5. Computerized tomography in a 56 year old woman. Lymph
nodes associated with the ascending colon tumor found to be of N2 stage.
Histopathology confirmed N2 stage.
FIGURE 6. Computerized tomography in a 72 year old woman. Lymph
nodes associated with the rectal cancer found to be of N1 stage. Histopa-
thology confirmed N1 stage.

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Hepato-Gastroenterology 59 (2012)M Duman, S Tas, EA Mecit, et al.
REFERENCES
1. You TY, Chien CRC, Wang YJ, et al.: Evaluation of contrast-en-
hanced computed tomographic colonography in detection of
local recurrent colorectal cancer. World J Gastroenterol 2006;
12(1):123-126.
Silva AC, Hara AK, Leighton JA, Heppel JP: CT colonogra-
phy with intravenous contrast material: varied appearances of
colorectal carcinoma. Radiographics 2005; 25:1321-1334.
Sun CH, Li ZP, Meng QF, Yu SP, Xu DS: Assessment of spiral
CT pneumocolon in preoperative colorectal carcinoma. World
J Gastroenterol 2005; 11(25):3866-3870.
Flippone A, Ambrosini R, Fuschi M, Marinelli T, Genovesi D,
Bonomo L: Preoperative T and N staging of colorectal cancer:
accuracy of contrast- enhanced multi-detector row CT colonog-
raphy-initial experience. Radiology 2004; 231:83-90.
Burton S, Brown G, Bees N, et al.: Accuracy of CT prediction
of poor prognostic features in colonic cancer. Br J Radiol 2008;
81:10-19.
Hennedige T, Teo L, Cheong WK, Venkatesh SK: Accuracy of
preoperative CT for local staging in colorectal carcinomas. Sin-
gapore Med J 2010; 51(6):475-480.
Ju H, Xu D, Li D, Chen G, Shao G: Comparison between endo-
luminal ultrasonography and spiral computerized tomography
for the preoperative local staging of rectal carcinoma. BioSci
Trends 2009; 3(2):73-76.
Miao YM, Amin Z, Healy J, et al.: A prospective single centre
study comparing computed tomography pneumocolon against
colonoscopy in detection of colorectal neoplasms. Gut 2000;
47:823-837.
Harvey CJ, Amin Z, Hare CMB, et al.: Helical CT pneumocolon
to assess colonic tumors. AJR 1998; 170:1439-1443.
10. Selcuk D, Demirel K, Ozer H, et al.: Comparison of virtual colo-
noscopy with conventional colonoscopy in detection of colorec-
tal polyps. Turk J Gastroenterol 2006; 17(4):288-293.
11. Shin SS, Jeong YY, Min JJ, Kim HR, Chung TW, Kang HK: Pre-
operative staging of colorectal cancer: CT vs. integrated FDG
PET/CT. Abdom Imaging 2008; 33:270-277.
12. Kosmider S, Stella DL, Field K, et al.: Preoperative investiga-
tions for metastatic staging of colon and rectal cancer across
multiple centres-what is the current practice. Colorectal Dis
2009; 11(6):592-600.
13. Iyer RB, Silverman PM, DuBrow RA, Charnsangavej C: Imag-
ing in the diagnosis, staging, and follow-up of colorectal cancer.
AJR 2002; 179:3-13.
14. Gollub MJ, Schwartz LH, Akhurst T: Update on colorectal can-
cer imaging. Radiol Clin North Am 2007; 45:85-118.
15. Dighe S, Purkayastha S, Swift I, Tekkis PP, Darzi A, Hern RA,
Brown G: Diagnostic precision of CT in local staging of colon
cancers: a meta-analysis. Clin Radiol 2010; 65:708-719.
16. Dighe S, Blake H, Koh MD, et al.: Accuracy of multidetector
computed tomography in identifying poor prognostic factors in
colonic cancer. Br J Surg 2010; 97:1407-1415.
17. Smith NJ, Bees N, Barbachano Y, Norman AR, Swift RI,
Brown G: Preoperative computed tomography staging of non-
metastatic colon cancer predicts outcome: implications for clin-
ical trials. Br J Cancer 2007; 96:1030-1036.
18. Kulinna C, Eibel R, Matzek W, et al.: Staging of rectal cancer:
diagnostic potential of multiplanar reconstructions with MDCT.
AJR 2004; 183:421-427.
19. McCollough CH: Optimization of multidetector array CT acqui-
sition parameters for CT colonography. Abdom Imaging 2002;
27(3):253-259.
2.
3.
4.
5.
6.
7.
8.
9.
20. Angelelli G, Macarini L, Lupo L, et al.: Rectal carcinoma:
CT staging with water as contrast medium. Radiology 1990;
177:511-514.
21. Chiesura-Corona M, Muzzio PC, Giust G, Zuliani M, Pucci-
arelli S, Toppan P: Rectal cancer: CT local staging with histo-
pathologic correlation. Abdom Imaging 2001; 26:134-138.
22. Hundt W, Braunschweig R, Reister M: Evaluation of spiral
CT in staging of colon and rectum carcinoma. Eur Radiol 1999;
9:78-84.
23. Thoeni RF: Colorectal cancer: radiologic staging. Radiol Clin
North Am 1997; 35:457-485.
24. Hulsmans FJ, Tio TL, Fockens P, Bosma A, Tytgat GN: Assess-
ment of tumor infiltration depth in rectal cancer with transrec-
tal sonography: caution is necessary. Radiology 1994; 190:715-
720.
25. Maier AG, Barton PP, Neuhold NR, Herbst F, Teleky BK, Lech-
ner GL: Peritumoral tissue reaction at transrectal US as a possi-
ble cause of overstaging in rectal cancer: histopathologic corre-
lation. Radiology 1997; 203:785-789.
26. Jin KN, Lee JM, Kim SH, Shin KS, Lee JY, Han JK, Choi BI: The
diagnostic value of multiplanar reconstruction on MDCT colo-
nography for the preoperative staging of colorectal cancer. Eur
Radiol 2006; 16:2284-2291.
27. Furukawa H, Ikuma H, Seki A, et al.: Positron emission to-
mography scanning is not superior to whole body Multidetec-
tor helical computed tomography in the preoperative staging of
colorectal cancer. Gut 2006; 55:1007-1011.
28. Ahmetoğlu A, Cansu A, Baki D, Kul S, Çobanoğlu Ü, Alhan E,
Özdemir F: MDCT with multiplanar reconstruction in the pre-
operative local staging of rectal tumor. Abdom Imaging 2011;
36(1):31-37.
29. Chamadol N, Ninpiethoon T, Bhudhisawasd V, Pairojkul C:
The role of CT scan in preoperative staging of colorectal carci-
noma. J Med Assoc Thai 2005; 88(12):1847-1853.
30. Balthazar EJ, Megibow AJ, Hulnick D, Naidich DP: Carcino-
ma of the colon: Detection and preoperative staging by CT. AJR
1988; 150:301-306.
31. Karantanas AH, Yarmenitis S, Papanikolaou N, Gourtsoyi-
annis N: Preoperative imaging staging of rectal cancer. Dig Dis
2007; 25:20-32.
32. Dighe S, Swift I, Brown G: CT staging of colon cancer. Clin Ra-
diol 2008; 63:1372-1379.
33. Ashraf K, Ashraf O, Haider Z, Rafique Z: Colorectal carcinoma,
preoperative evaluation by spiral computed tomography. JPMA
2006; 56:149-153.
34. Iannaccone R, Laghi A, Passariello R: Colorectal carcinoma:
detection and staging with multislice CT (MSCT) colonography.
Abdom Imaging 2005; 30:13-19.
35. Kanamoto T, Matsuki M, Okuda J, et al.: Preoperative evalua-
tion of local invasion and metastatic lymph nodes of colorectal
cancer and mesenteric vascular variations using multidetector-
row computed tomography before laparoscopic surgery. J Com-
put Assist Tomogr 2007; 31:831-839.
36. Veit P, Ruehm S, Kuehl H, Stergar H, Mueller S, Boskisch A,
Antoch G: Lymph node staging with dual-modality PET/CT: en-
hancing the diagnostic accuracy in oncology. Eur J Radiol 2006;
58:383-389.
37. Fenlon HM, McAney DB, Nunes DP, Clarke PD, Ferrucci JT:
Occlusive colon carcinoma: virtual colonoscopy in the pre-
operative evaluationof the proximal colon. Radiology 1999;
210:423-428.