Gene Regulation and Targeted Therapy in Gastric Cancer Peritoneal Metastasis: Radiological Findings from Dual Energy CT and PET/CT

This protocol describes the value of dual energy CT and PET/CT imaging methods in tumor imaging and efficacy evaluation. This article demonstrates the research methods and results acquired by dual energy CT and PET/CT to evaluate the gene regulation and targeted treatment of gastric cancer peritoneal metastasis.

Transcript

The overall goal of this non-invasive imaging procedure is to connect research on gastric cancer peritoneal metastasis and the mechanisms of tumorigenesis and to monitor tumor growth and the effects of therapeutic interventions on gastric cancer. This method can help answer some key questions in a tumor research feud, such as how the peritoneal metastasis mechanism functions and how to perform early diagnosis, treatment, response monitoring and prognosis. The main advantage of this technique is that it can identify the region and the metastasis process of gastric cancer and it can monitor the kidneys in response to treatments.

To begin this procedure establish the gastric cancer peritoneal metastasis animal model and set up the dual energy CT scan as outlined in the text protocol. After selecting and anesthetizing the experimental mice, click the new patient icon in the DECT program. Input the mouse's basic information including it's patient ID and name.

Then in the user protocol section click abdomen protocol and select the animal DECT scan protocol to enter the operation interface. Move each anesthetized mouse onto an animal fixture platform in the supine position. Using tape fix the mouses tail to make sure it does not bend.

Sterilize the tail with alcohol. After this move the CT scan bed so that the external positioning line laser is over the mouse's lower abdomen. When the positioning is complete click the reset button.

Next click confirm. Follow the flashing order of the buttons on the keyboard to complete the scout scanning. Then select the next series icon and enter the interface for non-enhanced scanning.

In the right screen set the start location and end location on the scout views to define the scan range. Maintain the same range in lateral scout and AP scout and cover the entire body volume of the animal. Click the confirm icon and then follow the flashing order of the buttons on the keyboard to complete the scout scanning.

After this inject each mouse with iopamidol through the tail vein. Click next series to perform enhanced scanning. Set the start location and end location as before during the non-enhanced scan.

Next click the confirm icon and follow the flashing order of the buttons on the keyboard to complete the dynamic enhanced scans, including arterial phase, portal phase and delayed phase. After this click end exam to exit the scanning interface. The image series will automatically be uploaded to the workstation.

First locate the mice series on the DECT workstation interface. Select the plus C mono phase series list. Open the GSI volume viewer.

And select the GSI VV general protocol from the GSI protocol manager interface. Then click the view type active annotation in the upper left corner of the image view ports and select coronal orientation from the drop down menu. Other orientation images like transverse or sagittal position can be selected from this drop-down menu as well.

For one image view port click the volume one active annotation and select mono volumes from the drop-down menu. In a second image view port select iodine water volumes. Click and hold the left mouse button to drag the image from the iodine water view port to the mono view port.

Check the mix the views box to get the color fused images. After this click and drag from the center of the image scroll icon to observe the images. Save any that show positive results as color fused images.

To begin set up the micro pet CT imaging protocol as outlined in the text protocol. After injecting the FDG and anesthetizing move the animal to the entrance of the pet CT scanner. Click the laser icon from the toolbar viewer and use the touch pad control interface to move the bed so that the mouse's abdomen is located in the center of the pet and CT fields of view.

In the laser aligned window select the first scan type as CT scan with pet acquisition included in the workflow as the option. Next open the scout view window and acquire a scout view XR radiograph. Adjust the position of the animal bed so that the CT center field of view is located at the center of the mouse's body.

Select the prepared micro pet CT protocol. Input the number of mice to be successively imaged in the pop-up window. Click the set up option and enter the weight.

Then click the set up option again and follow the pop up window instructions to complete the set up. Click the start workflow icon to start scanning. After the scanning is complete evaluate the quality of the acquired CT and pet images.

Transfer the data through the network to the post imaging analysis. Next open the pet CT workstation software and import the CT and pet image series data. In the registration window click the general analysis option to register CT and pet images together.

Then we click the button in the tools application to adjust the window and level of images. Under the review window choose the sky model to show a perfect alignment between the CT and pet images. In the region of interest quantification window identify the peritoneal nodules with references provided by the co-registered images.

Draw the region of interest or ROI with tools over the fused images. Edit the size and shape of the ROI and record the maximum standard uptake value. Then output and save the selected merged images.

In this study, DECT and pet CT scanning are performed on nude mice after two weeks of cell lined injections. GSI images yielded excellent results for displaying subcutaneous metastasis beyond the contour of the abdomen for the SFRP1 over expression group. And metastasis with peripheral enhancement is confirmed by color scale image.

The acquired pet CT images depict focally abnormal FDG uptake of metastasis, including in the peritoneal and subcutaneous metastasis. The gross specimen and histological section further illustrate that peritoneal metastasis and large subcutaneous metastasis. The abdominal cavity in the SFRP1 empty loading group contains no visible lesions, obvious abnormal enhancements or high FDG uptake.

However, the gross specimen and histological results confirm that implantation of this group was successful. Non-invasive imaging scans for mice treated with transforming growth factor beta one depict obvious enhancement and focal abnormal fludeoxyglucose uptake of metastasis. The gross specimens for this treatment group are seen to have only eight nodules of peritoneal metastasis with diffused distribution in the abdominal cavity.

However, mice in the control group that was given normal saline also showed visible legions and focally abnormal uptake of metastasis. These gross specimens are seen to have 22 nodules of peritoneal metastasis and the local metastasis nodules were adherent to the abdominal cavity. We are attempting this procedure.

It is important to make sure that the time period of each experiment or arrangement is reasonable. And performance study has the necessary animal For researchers in a feud of oncology and medicine to research the metastasis mechanism and prognosis evaluation for other tumors like ovarian cancer or rectal cancer. After watching this video you should with understanding of how to use a QCT in a part of CT to access the process of tumor peritoneal metastasis affected by and the treatment efficacy with Don't forget that working with imaging can be extremely hazardous and the precautions such as should always be taken while performing this procedure.

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Journal (Medicine)

Gene Regulation and Targeted Therapy in Gastric Cancer Peritoneal Metastasis: Radiological Findings from Dual Energy CT and PET/CT

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