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- “Probably the single best staging method for malignant conditions of the abdomen and retroperitoneum is a multiphasic, contrast-enhanced CT with thin, preferably submillimeter, axial sections from chest to pelvis. Importantly, all CT scans are not alike, and a single-phase, thick-slice CT is inadequate for staging. Surprisingly, this point is not stressed by consensus guidelines for gastric cancer. With a high-resolution CT scan, most liver, lung, lymph node, and overt peritoneal disease will be detected, making other staging studies unnecessary.”
Optimal Staging for Gastric Cancer Starts With High-Resolution Computed Tomography
Audrey E. Brown, Eric K. Nakakura
JAMA Surgery Published online October 27, 2021 - "Another important point to emphasize is that a typical FDG-PET/CT does not include a high-resolution, contrast- enhanced CT scan. Rather, the CT accompanying an FGD- PET/CT is usually done without contrast, making an FDG- PET/CT alone inadequate to stage gastric cancer. In patients with gastric cancer, FDG-PET/CT has been shown to be most useful in assessing metastases to lymph nodes, particularly those that are not pathologically enlarged. Prior to obtaining an FDG-PET/CT, it is imperative to obtain a multiphasic, contrast-enhanced CT with thin (preferably submillimeter) axial sections from chest to pelvis. A request for 0.625-mm axial sections increases the resolution by 8-fold compared with 5-mm cuts. Now, that is high resolution!”
Optimal Staging for Gastric Cancer Starts With High-Resolution Computed Tomography
Audrey E. Brown, Eric K. Nakakura
JAMA Surgery Published online October 27, 2021 - CCS is a non-familial gastrointestinal polyposis syndrome. The first two cases of CCS were described by Cronkhite and Canada in the year 1995. To the best of our knowledge, more than 400 cases have been reported so far in the literature, two-third of which are from Japan, with a male preponderance (male-female ratio is 2:1). The most common age of onset of this disease is 50–60 years. The disease has characteristic features of diffuse gastrointestinal polyposis and ectodermal changes (alopecia, hyperpigmentation and onychodystrophy). Gastrointestinal polyposis leads to malabsorption and protein-losing enteropathy, resulting in clinical symptoms of abdominal pain, diarrhoea and weight loss.
- The differential diagnoses of polyps include juvenile polyposis, hyperplastic polyposis, lipomatous polyposis, nodular lymphoid hyperplasia, inflammatory polyposis, lymphomatous polyposis, Peutz-Jeghers polyposis and Menetrier’s disease. Confusion can also arise with villous atrophy, Helicobacter pylori gastritis, eosinophilic gastroenteritis and intestinal candidiasis. The aetiology of CCS is uncertain.
- “MDCT using gaseous and hydro-distension of stomach is an excellent modality for near accurate preoperative T staging of gastric cancer. However, CT has a limited role in the N staging of gastric cancer. This study also suggested that the combined use of virtual gastroscopy and MPR images helps in better detection of early gastric cancers.”
Preoperative Staging of Gastric Cancer Using Computed Tomography and Its Correlation with Histopathology with Emphasis on Multi-planar Reformations and Virtual Gastroscopy
Wani AH et al.
Journal of Gastrointestinal Cancer https://doi.org/10.1007/s12029-020-00436-6 - Our study suggests that MDCT using gaseous and hydrodistension of stomach is an excellent modality for near accurate preoperative tumor staging of gastric cancer, thereby helping in determining its operability. The addition of CT virtual gastroscopy to multi-planar reformations helps in detection of early gastric cancers. CT has limited role in nodal staging of gastric cancer.”
Preoperative Staging of Gastric Cancer Using Computed Tomography and Its Correlation with Histopathology with Emphasis on Multi-planar Reformations and Virtual Gastroscopy
Wani AH et al.
Journal of Gastrointestinal Cancer https://doi.org/10.1007/s12029-020-00436-6
- Gastric Cancer: Statistics 2019
- Gastric Cancer: Statistics 2019
- Gastric Cancer: Statistics 2019
- Gastric Cancer: Statistics 2019
- Gastric Cancer: Statistics 2019
- Gastric Cancer: Statistics 2019
- Gastric Cancer: Statistics 2019
- Gastric Cancer: Statistics 2019
- Gastric Cancer: Statistics 2019
- “In all cases of penetrating trauma, it is crucial to identify the injury tract. The stomach often collapses around the site of injury, so that a defect is not visible at imaging, making the injury tract the only sign of gastric trauma.”
CT of Gastric Emergencies Guniganti PG et al. RadioGraphics 2015; 35:1909–1921 - “Arterial supply to the stomach comes from all three branches of the celiac axis: the left gastric, common hepatic, and splenic arteries, forming two arterial arcades. Numerous anastomoses make the stomach relatively resistant to ischemia.”
CT of Gastric Emergencies Guniganti PG et al. RadioGraphics 2015; 35:1909–1921
- “The optimal cut-off values of SAD were determined as follows: overall, 9 mm; differentiated type, 9 mm; undifferentiated type, 8 mm; lesser curvature region, 7 mm; greater curvature region, 6 mm; and suprapancreatic region, 9 mm. The diagnostic accuracies for lymph node metastasis using individual cut-off values were 71.1% based on histological type and 76.6% based on region of lymph node location.”
Accuracy of multidetector-row CT in diagnosing lymph node metastasis in patients with gastric cancer. Saito Tet al. Eur Radiol. 2015 Feb;25(2):368-74.
- “The purpose of this study was to determine the optimal cut-off value of lymph node size for diagnosing metastasis in gastric cancer with multidetector-row computed tomography (MDCT) after categorizing perigastric lymph nodes into three regions.
The long-axis diameter (LAD) and short-axis diameter (SAD) of all visualized lymph nodes were measured with transverse MDCT images. The locations of lymph nodes were categorized into three regions: lesser curvature, greater curvature, and suprapancreatic. The diagnostic value of lymph node metastasis was assessed with receiver operating characteristic (ROC) analysis.”
Accuracy of multidetector-row CT in diagnosing lymph node metastasis in patients with gastric cancer. Saito Tet al. Eur Radiol. 2015 Feb;25(2):368-74.
- “CT scan is routinely used for preoperative staging. It has an overall accuracy of 43% to 82% for T staging. PET/CT has a low detection rate because of the low tracer accumulation in diffuse and mucinous tumor types, which are frequent in gastric cancer. It has a significantly lower sensitivity compared to CT in the detection of local lymph node involvement (56% vs.78%), although it has an improved specificity (92% vs. 62%).53 Combined PET/CT imaging, on the other hand, has several potential advantages over PET scan alone. PET/CT has a significantly higher accuracy in preoperative staging (68%) than PET (47%) or CT (53%) alone. Recent reports have confirmed that PET alone is not an adequate diagnostic procedure in the detection and preoperative staging of gastric cancer but it could be helpful when used in conjunction with CT.”
NCCN Guidelines Gastric Cancer (2015) - Syndromes Associated with Increased Incidence of Gastric Cancer
- Hereditary diffuse gastric cancer (HDGC)
- Lynch syndrome (also referred to as hereditary non-polyposis colorectal cancer)
- Juvenile polyposis syndrome (JPS)
- Peutz-Jeghers syndrome (PJS)
- Familial adenomatous polyposis (FAP) - Syndromes Associated with Increased Incidence of Gastric Cancer
- Hereditary diffuse gastric cancer (HDGC)
- autosomal dominant syndrome characterized by the development of gastric cancers, predominantly the diffuse type, at a young age
- average age at diagnosis of gastric cancer is 37 years, and the lifetime risk for the development of gastric cancer by the age of 80 years is estimated at 67% for men and 83% for women
- Germline truncating mutations in the tumor suppressor gene CDH1 (encoding the cell-to-cell adhesion protein E-cadherin) are found in 30% to 50% of families with HDGC - Syndromes Associated with Increased Incidence of Gastric Cancer
- Lynch syndrome (also referred to as hereditary non-polyposis colorectal cancer)
- autosomal dominant syndrome characterized by the early onset of colorectal cancer and endometrial cancer as well as a variety of other cancers including gastric cancer
- Gastric cancer is the second most common extracolonic cancer (after endometrial cancer) in patients with Lynch syndrome, and these patients have a 1% to 13% risk of developing gastric cancer, predominantly the intestinal type, occurring at an earlier age than the general population. - Syndromes Associated with Increased Incidence of Gastric Cancer
- Juvenile polyposis syndrome (JPS)
- rare autosomal dominant syndrome characterized by the presence of multiple juvenile polyps along the GI tract and is associated with an increased risk of developing GI cancers.
- JPS arises from a germline mutation in the SMAD4 or BMPR1A genes.
- The lifetime risk of developing GI cancers in patients with JPS varies from 9% to 50% and varies with the type of mutation. In patients with gastric polyps, JPS carries a lifetime risk of 21% for developing gastric cancer. - Syndromes Associated with Increased Incidence of Gastric Cancer
- Peutz-Jeghers syndrome (PJS)
- autosomal dominant syndrome caused by germline mutations in the STK11/LKB1 tumor suppressor gene. Mutations in the STK11/LKB1 gene have been identified in 30% to 80% of patients.
- PJS is characterized by mucocutaneous pigmentation and GI polyposis and is associated with an elevated risk of developing GI cancers.36-40 Individuals with PJS have a 29% lifetime risk of developing gastric cancer. - Syndromes Associated with Increased Incidence of Gastric Cancer
- Familial adenomatous polyposis (FAP)
- an inherited autosomal-dominant colorectal cancer syndrome resulting from the germline mutations in the adenomatous polyposis coli (APC) gene on chromosome 5q
- FAP is characterized by adenomatous colorectal polyps that progress to colorectal cancer at 35 to 40 years of age. Upper GI polyps in the stomach, duodenum and periampullary region are the most common extracolonic manifestations of FAP.
- The majority (approximately 90%) of gastric polyps is nonadenomatous benign fundic gland polyps, developing in approximately 50% of patients with FAP whereas gastric adenomatous polyps represent 10% of gastric polyps and can lead to gastric cancer. - Accuracy of CT for Lymph Node Involvement in Gastric Cancer
- Location of nodes
- Size of nodes
- Number of nodes present
- Attenuation/enhancement of the nodes - “The diagnostic accuracy of lymph node metastasis in gastric cancer was improved by using individual cut-off values for each lymph node region.”
Accuracy of multidetector-row CT in diagnosing lymph node metastasis in patients with gastric cancer.
Saito T et al.
Eur Radiol. 2015 Feb;25(2):368-74 - “The area under the curve was larger for SAD than LAD in all groups. The optimal cut-off values of SAD were determined as follows: overall, 9 mm; differentiated type, 9 mm; undifferentiated type, 8 mm; lesser curvature region, 7 mm; greater curvature region, 6 mm; and suprapancreatic region, 9 mm. The diagnostic accuracies for lymph node metastasis using individual cut-off values were 71.1% based on histological type and 76.6% based on region of lymph node location.”
Accuracy of multidetector-row CT in diagnosing lymph node metastasis in patients with gastric cancer.
Saito T et al.
Eur Radiol. 2015 Feb;25(2):368-74 - OBJECTIVES: The purpose of this study was to determine the optimal cut-off value of lymph node size for diagnosing metastasis in gastric cancer with multidetector-row computed tomography (MDCT) after categorizing perigastric lymph nodes into three regions.
CONCLUSIONS: The diagnostic accuracy of lymph node metastasis in gastric cancer was improved by using individual cut-off values for each lymph node region.
Accuracy of multidetector-row CT in diagnosing lymph node metastasis in patients with gastric cancer.
Saito T et al.
Eur Radiol. 2015 Feb;25(2):368-74
- “The CT findings helpful for differentiating gastric adenocarcinoma from malignant gastric lymphoma are the pattern of involvement, the perigastric fat plane, and the location of lesion. Localized involvement of the lesion, abnormal perigastric fat plane and location involving one region of the stomach tend to indicate gastric adenocarcinoma; while diffused involvement of the lesion, preserved perigastric fat plane and location involving more than one region of the stomach tend to indicate malignant gastric lymphoma.”
Computed tomographic features of adenocarcinoma compared to malignant lymphoma of the stomach.
Chamadol N et al
J Med Assoc Thai. 2011 Nov;94(11):1387-93.
"MDCT may be a reliable means of noninvasive diagnosis in the care of patients with endoscopically detected giant gastric folds and may be useful fot differentiating benign from malignant disease."
MDCT of Giant Gastric Folds: Differential Diagnosis
Chen CY et al.
AJR 2010; 195:1124-1130"The assessment of direct transmural and extraserosal spread of disease (T staging) and nodal involvement (N staging) has improved markedly with the advent of 3D MDCT with its excellent spatial and temporal resolution and its ability for multiplanar image reconstruction."
Gastric Cancer: Patterns of Disease Spread via the Perigastric Ligaments Shown by CT
Tan CH et al.
AJR 2010; 195:398-404"However, the tumor detection rate was significantly higher on gas distention CT scans using 2D and surface shaded display images for both radiologists compared with the rates for water distension CT scans or gas distention CT scans using only 2D images."
Three-Dimensional MDCT for Preoperative local Staging of Gastric Cancer Using Gas and Water Distension Methods: A Retrospective Cohort Study
Park HS et al.
AJR 2010; 195:1316-1323"MDCT using the gas distention technique showed performance comparable to that of water distension technique for the T staging of preoperative gastric cancer with better lesion detectability."
Three-Dimensional MDCT for Preoperative local Staging of Gastric Cancer Using Gas and Water Distension Methods: A Retrospective Cohort Study
Park HS et al.
AJR 2010; 195:1316-1323"In our study, MDCT had results comparable with those of conventional gastroscopy in differentiation of malignant and benign gastric ulcers. The sensitivity was 80.8-90.9% and the specificity was 73.1-77.8% on virtual gastroscopic images and the sensitivity 73.1%-80.8% and the specificity on MPR images."
MDCT for Differentiation of Category T1 and T2 Malignant Lesions from Benign Gastric Ulcers
Chen CY et al.
AJR 2008; 190:1505-1511"MDCT combined with virtual gastroscopy and multiplanar reconstruction enhances the morphologic details of gastric ulcers and is a useful way to differentiate malignant (T1 and T2) and benign gastric ulcers."
MDCT for Differentiation of Category T1 and T2 Malignant Lesions from Benign Gastric Ulcers
Chen CY et al.
AJR 2008; 190:1505-1511"The preoperative prediction of T4 tumors is of particular importance in determining tumor resectability, and the optimal extent of surgery. Researchers in some studies reported that the combined resection of invaded organs increased mortality and morbidity without overall survival gain, and T4 tumors have been traditonally regarded as unresectable."
Staging of T3 and T4 Gastric Carcinoma with Multiplanar CT: Added Value of Multiplanar Reformations for Prediction of Adjacent Organ Invasion
Kim YH et al.
Radiology 2009; 250:767-775"In discriminating between T3 and T4 tumors, even if the fat plane intervening between the primary tumor and adjacent organ is effaced, invasion is not likely to be present if a distinct and smooth interface is maintained between them, whereas an indistinct or irregular interface probably suggests invasion."
Staging of T3 and T4 Gastric Carcinoma with Multiplanar CT: Added Value of Multiplanar Reformations for Prediction of Adjacent Organ Invasion
Kim YH et al.
Radiology 2009; 250:767-775"A combination of transverse CT and multiplanar reconstruction (MPR) is more accurate than transverse CT images alone in aiding prediction of tumor invasion of adjacent organs, particularly the transverse colon or mesocolon and pancreas, and , therefore in helping to identify patients with T4 gastric cancer."
Staging of T3 and T4 Gastric Carcinoma with Multiplanar CT: Added Value of Multiplanar Reformations for Prediction of Adjacent Organ Invasion
Kim YH et al.
Radiology 2009; 250:767-775- "MPR images are useful in identifying candidates for extended surgery and in planning appropriate surgical procedures."
Staging of T3 and T4 Gastric Carcinoma with Multiplanar CT: Added Value of Multiplanar Reformations for Prediction of Adjacent Organ Invasion
Kim YH et al.
Radiology 2009; 250:767-775 "Adding MPR images to transverse CT images improves the capability for distinguishing T3 from T4 gastric cancer and prediction of adjacent organ invasion."
Staging of T3 and T4 Gastric Carcinoma with Multiplanar CT: Added Value of Multiplanar Reformations for Prediction of Adjacent Organ Invasion
Kim YH et al.
Radiology 2009; 250:767-775- N Staging
- Lymphatic spread is found in 74-88% of patients with gastric cancer because of the abundant lymphatic vessels in the stomach
- The frequency of lymphatic mets is related to the size and depth of tumor penetration "The diagnostic performance for overall lesion detection in patients with early gastric cancer was significantly higher with virtual gastroscopy than with 2D axial CT. Virtual gastroscopy showed a higher sensitivity for EGC than 2D axial CT."
Diagnostic Performance of Virtual Gastroscopy Using MDCT in Early Gastric Cancer Compared with 2D Axial CT: Focusing on Interobserver Variation
Kim JH et al.
AJR 2007; 189:299-305"Virtual gastroscopy showed excellent results with a good interobserver reliability for the detection of early gastric cancer compared with 2D axial CT."
Diagnostic Performance of Virtual Gastroscopy Using MDCT in Early Gastric Cancer Compared with 2D Axial CT: Focusing on Interobserver Variation
Kim JH et al.
AJR 2007; 189:299-305- Gastric Cancer: Role of CT
- CT is the primary imaging modality for staging gastric cancer and can detect up to 95% of primary tumors in patients with AGC
- In patients with EGC, CT often used for N and M staging only, as visualization of the primary tumor can be difficult on axial imaging alone.
- Gastric Cancer
- Significant cause of worldwide morbidity & mortality
- Estimated 5 year survival rate less than 20%
- But, early gastric cancers are curable, with a survival rate of more than 90% - Peak incidence between 50-60Highest prevalence in Japan
Predisposing factors
- Atrophic gastritis, pernicious anemia (2-3 X), gastric polyps, partial gastrectomy, Menetrier, H. pylori (2-3X), Adenomatous polyps, Blood type A, smoking
- Gastric Cancer
- Decreasing incidence in the US
- Estimated 22,000 cases in US /year
- 3rd most common GI malignancy in US after colorectal & pancreatic malignancy
- Adenocarcinoma (95%)
- Most are at an advanced stage at time of diagnosis
- 2/3 of patients are not candidates for curative resection Lymphoma vs Adenocarcinoma
CT findings can overlap
Lymphoma
- Adenopathy can extend below the renal hilum without perigastric adenopathy
- Can extend into duodenum
- Nodes usually larger in lymphoma
- Perigastric fat plane more likely to be preserved.- Gastric Cancer
Nodal metastases- CT limitations
*Metastatic disease is not reliably associated with lymph node enlargement
-- metastases have been found in 2mm nodes
-- large nodes can be reactive
*Sensitivity of CT (47-97%), EUS is better
*Accuracy not really improved with 3D imaging. (Kim et al, Radiology 2005) - N Staging
- Lymphatic spread is found in 74-88% of patients with gastric cancer because of the abundant lymphatic vessels in the stomach
- The frequency of lymphatic mets is related to the size and depth of tumor penetration "The diagnostic performance for overall lesion detection in patients with early gastric cancer was significantly higher with virtual gastroscopy than with 2D axial CT. Virtual gastroscopy showed a higher sensitivity for EGC than 2D axial CT."
Diagnostic Performance of Virtual Gastroscopy Using MDCT in Early Gastric Cancer Compared with 2D Axial CT: Focusing on Interobserver Variation
Kim JH et al.
AJR 2007; 189:299-305"Virtual gastroscopy showed excellent results with a good interobserver reliability for the detection of early gastric cancer compared with 2D axial CT."
Diagnostic Performance of Virtual Gastroscopy Using MDCT in Early Gastric Cancer Compared with 2D Axial CT: Focusing on Interobserver Variation
Kim JH et al.
AJR 2007; 189:299-305- Gastric Cancer: Role of CT
- CT is the primary imaging modality for staging gastric cancer and can detect up to 95% of primary tumors in patients with AGC
- In patients with EGC, CT often used for N and M staging only, as visualization of the primary tumor can be difficult on axial imaging alone. - Gastric Cancer
- Significant cause of worldwide morbidity & mortality
- Estimated 5 year survival rate less than 20%
- But, early gastric cancers are curable, with a survival rate of more than 90% - Gastric Cancer
- Decreasing incidence in the US
- Estimated 22,000 cases in US /year
- 3rd most common GI malignancy in US after colorectal & pancreatic malignancy
- Adenocarcinoma (95%) Most are at an advanced stage at time of diagnosis
- 2/3 of patients are not candidates for curative resection
- Peak incidence between 50-60
- Highest prevalence in Japan
- Predisposing factors
----Atrophic gastritis, pernicious anemia (2-3 X), gastric polyps, partial gastrectomy, Menetrier, H. pylori (2-3X), Adenomatous polyps, Blood type A, smoking
- Multiple Gastric Tumors: Differential Diagnosis
- Carcinoid tumor
- Hyperplastic polyps (75% of cases)
- Adenomatous polyps Peutz-Jeghers syndrome
- Multiple hamartoma syndrome (Cowden disease)
Multiple Gastric Carcinoids
wang E, Sagel SS, Brunt EM
RadioGraphics 2009;29:1206-1209 - "MDCT combined with virtual gastroscopy and multiplanar reconstruction enhances the morphologic details of gastric ulcers and is a useful way to differentiate malignant (T1 and T2) and benign gastric ulcers."
MDCT for Differentiation of Category T1 and T2 Malignant Lesions from Benign Gastric Ulcers
Chen CY et al.
AJR 2008; 190:1505-1511 - "In our study, MDCT had results comparable with those of conventional gastroscopy in differentiation of malignant and benign gastric ulcers. The sensitivity was 80.8-90.9% and the specificity was 73.1-77.8% on virtual gastroscopic images and the sensitivity 73.1%-80.8% and the specificity on MPR images."
MDCT for Differentiation of Category T1 and T2 Malignant Lesions from Benign Gastric Ulcers
Chen CY et al.
AJR 2008; 190:1505-1511 - "In our study, MDCT had results comparable with those of conventional gastroscopy in differentiation of malignant and benign gastric ulcers."
MDCT for Differentiation of Category T1 and T2 Malignant Lesions from Benign Gastric Ulcers
Chen CY et al.
AJR 2008; 190:1505-1511 - Gastric Cancer
- Decreasing incidence in the US
- Estimated 22,000 cases in US /year
- 3rd most common GI malignancy in US after colorectal & pancreatic malignancy
- Adenocarcinoma (95%)
- Most are at an advanced stage at time of diagnosis
- 2/3 of patients are not candidates for curative resection - Gastric Cancer
- Peak incidence between 50-60
- Highest prevalence in Japan
- Predisposing factors
- Atrophic gastritis, pernicious anemia (2-3 X), gastric polyps, partial gastrectomy, Menetrier, H. pylor1 (2-3X), Adenomatous polyps, Blood type A, smoking - Gastric Cancer
- Significant Cause of worldwide morbidity & mortality
- Estimated 5 year survival rate less than 20%
- But, early gastric cancers are curable, with a survival rate of more than 90% - T Staging
- T1
- Strong enhancement with focal thickening in inner and/or middle layers (no enhancement outer layer)
- Enhancement, but no thickening
- No abnormal enhancement but non-transmural thickening
- T2
- Transmural enhancement with focal thickening or obliteration of middle layer - T Staging
- T3
- Irregular outer border of thickened wall or loss of fat plane
- T4
- Gross infiltration of adjacent organs - T Staging
- EUS is more accurate than CT in preoperative T staging
- EUS can depict the normal gastric wall with 5 layers so the depth of tumor penetration can be evaluated with excellent detail. - Early Gastric Cancer (T1)
- CT Findings
- Focal thickening or enhancement
- Shallow ulceration - Advanced Gastric Cancer (T2-T4)
- Primary Tumor- CT Findings
- Focal wall thickening (transmural)
- Polypoid mass
- +/- ulceration
- +/- calcification
- Diffuse thickening and rigidity (linitis plastica) - Gastric Cancer (T3 and T4)
- Perigastric spread- CT Findings
- Extension of tumor into perigastric fat
- Increased attenuation in fat surrounding the stomach
- Obliteration of fat plane between tumor and adjacent structures
- Direct invasion of adjacent organs - T-Staging
- Differentiation between T1 and T2 and T3 or T4 was correct 87% on transverse and 92% on 3D
- Improvement in staging mainly in T-staging, not N or M staging. - N-Staging
- N0 - no adenopathy
- N1-N3
- short axis > 6mm for perigastric nodes,
- >8 mm for extragastric nodes
- Other criteria for malignant nodes
- Round shape
- Missing or eccentric fatty hilum
- Marked heterogeneous enhancement - N-Staging
- N1 - 1-5 affected nodes
- N2 - 6-15 affected nodes
- N3 >15 affected nodes - N-Staging
- Lymphatic spread is found in 74-88% of patients with gastric cancer because of the abundant lymphatic vessels in the stomach
- The frequency of lymphatic mets is related to the size and depth of tumor penetration - Gastric Cancer
- Nodal metastases- CT limitations
- Metastatic disease is not reliably associated with lymph node enlargement
- metastases have been found in 2mm nodes
- large nodes can be reactive
- Sensitivity of CT (47-97%), EUS is better
- Accuracy not really improved with 3D imaging. (Kim et al, Radiology 2005) - Gastric Cancer
- Distant metastases
- CT is the imaging modality of choice for detcting metastases.
- Only better is Surgery or laparoscopy
- Still some limitations
- Small liver mets
- Small peritoneal implants - M-Staging
- Hematogenous
- Liver, Lungs, Adrenals
- Kidneys, Bone, Brain, Ovary (Krukenberg)
- Rectal wall ( Blumer shelf)
- Peritoneal Adenopathy outside perigastric region is M1
- Left supraclavicular node (Virchow node) - "Multi-detector row CT scanning of patients with gastric cancer gave 93% accuracy in the assessment of serosal invasion in patients with gastric cancer."
T Staging of Gastric Cancer: Role of Multidetector Row CT
Kumano S et al. Radiology 2005; 237:961-966 - "In conclusion, multidetector row CT in patients with gastric cancer is a valid method for pre-operative staging, especially given the high accuracy of CT for the assessment of serosal invasion in gastric cancer."
T Staging of Gastric Cancer: Role of Multidetector Row CT
Kumano S et al. Radiology 2005; 237:961-966 - "Three dimensional CTA using MDCT clearly revealed individual vascular anomalies around the stomach and could play an important role in safely facilitating the laparoscopy assisted gastrectomy procedure."
Preoperative Assessment of Vascular Anatomy Around the Stomach by 3D Imaging Using MIDST Before Laparoscopy Assited Gastrectomy
Matsuki M et al
AJR 2004;183:145-151 - "This technique made possible safe and rapid manipulation of the origins of the arteries and veins and lymph node excision without incurring injury to the involved arteries and veins."
Preoperative Assessment of Vascular Anatomy Around the Stomach by 3D Imaging Using MIDST Before Laparoscopy Assisted Gastrectomy
Matsuki M et al
AJR 2004;183:145-151 - Gastric Cancer: CT Evaluation of Postoperative Recurrence
- Local recurrence
- Direct extension to adjacent organs via ligaments or peritoneal reflections
- Lymphatic spread
- Intraperitoneal seeding
- Hematogenous metastases - "When thin collimation is used, near isotrophic imaging of the stomach is possible, allowing high quality multiplanar reformation and three dimensional reconstruction of gastric images."
Dedicated Multidetector CT of the Stomach: Spectrum of Diseases
Ba-Ssalamah A et al.
RadioGraphics 2003; 23:625-644 - Gastric Adenocarcinoma: Sites of Metastases
Lymphatic spread
- Local and distant lymph nodes
Peritoneal spread
- Peritoneal implants
- Implants on the ovaries (Krukenberg tumor) - Gastric Adenocarcinoma: Sites of Metastases
Hematogenous spread
- Liver
- Lung
- Adrenal gland
- Bone
- brain - Gastric Adenocarcinoma: T Staging (bottom line)
- T1- minimal focal wall thickening
- T2- moderate wall thickening without spread to soft tissues around stomach
- T3- moderate wall thickening with perigastric spread of disease
- T4- infiltration of adjacent organs