3d scanning following en bloc resection of solid tumor for virtual mapping of cancer resections

Advanced CAD Imaging for Surgical Margin Analysis in Cancer Care

The goal of oncologic resection is the complete removal of cancer with surgical margins microscopically clear of tumor cells. In head and neck cancer, the surgical margin status is the most important pathologic risk factor1. A positive surgical margin increases the risk of 5-year local recurrence and all-cause mortality by &#62;90%2. Despite advances in medical technology and surgical techniques in recent years, positive margin rates in head and neck cancer remain high3. For locally advanced oral cavity cancers, the positive margin rate within the United States is 18.1%4.
For head and neck surgeons to ensure complete oncologic resection while minimizing disruption of surrounding structures, intraoperative sampling of margins via frozen section analysis (FSA) is performed. FSA provides a rapid intraoperative pathology consultation that is widely used and is the standard of care5,6,7,8,9. Fresh tissue is frozen, thinly sliced, placed on a glass slide, and stained for immediate interpretation while the patient is still under anesthesia.
Head and neck oncologic specimens present several distinct challenges in accurately assessing margin status, including the anatomic complexity of head and neck cancer specimens, the minimal reserve in the head and neck region for wide excision given the proximity to vital structures such as the eyes, face, and important nerves and vasculature, and the multiple tissue types often present in the resected specimen (i.e., mucosa, cartilage, muscle, bone)10,11. Thus, a specimen-based approach to margin analysis requires an enhanced level of communication between surgeon and pathologist12. A face-to-face conversation is often warranted to ensure correct specimen orientation and discussion of concerning margins. However, this is not always safe or feasible as it requires either the surgeon to leave the operating room (OR) while the patient remains under general anesthesia or the pathologist to leave the gross pathology lab, interrupting their workflow. In addition, there may be a significant travel time between the OR and the pathology lab, or in some cases, the pathology lab may be off-site altogether.
Following FSA, the oncologic specimen is fixed in formalin and formally processed through inking, sectioning, and margin sampling. Slides are created and microscopically interpreted by the pathologist to create a final pathology report. For complex head and neck cancer resection, this can often take 1-2 weeks. Unfortunately, processing of the specimen commonly results in the destruction of the resected cancer specimen. This may create further confusion as the final pathology report, multidisciplinary tumor board discussions, adjuvant radiation therapy planning, and re-resection in the setting of positive margins, must all proceed without a visual record of the oncologic specimen and its pathologic processing.
To address this clinical unmet need, we have developed a 3D scanning and specimen mapping protocol to enhance communication between surgeons, pathologists, and other members of the multidisciplinary cancer care team.

Author Spotlight: 3D Scanning and Augmented Reality for Enhanced Cancer Surgery Communication

Enhanced Communication of Tumor Margins Using 3D Scanning and Mapping

The scope of our research is to use 3D scanning and augmented reality technology to improve communication of cancer surgery results among the multidisciplinary cancer care team. More specifically, we're hoping to allow for a surgeon to re-resect cancer more precisely and allow for more precise radiation therapy. In the hospital environment, space is often limited, and finding additional room for extra personnel and equipment can be difficult.The learning curve on this protocol can also be challenging, especially for those without prior experience in 3D scanning and computer-aided design. We've created a 3D scanning and virtual mapping protocol for cancer specimens, providing a permanent visual record to go alongside written pathology reports. This is a powerful communication tool for the entire cancer care team and is now being investigated in multidisciplinary tumor board discussions, as well as adjuvant radiation therapy treatment planning.When a surgical specimen is processed for pathologic analysis, it is often destroyed, without any visual documentation. This results in lengthy written pathology reports and can often lead to challenging clinical scenarios in cases of a close or positive margin. Our research protocol creates an interactive, permanent visual record of the resected cancer specimen.Our protocol offers a novel visual representation of a surgically resected oncologic specimen and a map of how it was processed pathologically. This data previously did not exist and now allows providers to look back at a specimen for reference, multidisciplinary care discussions, and future treatment planning.

3D Scanning Following En Bloc Resection of Solid Tumor for Virtual Mapping of Cancer Resections

To begin, set up the 3D scanner for scanning the solid tumor. Place a thin sheet of plastic on the 3D scanner turntable to protect the target points from human tissue. Position the prepared resected oncologic specimen onto the plastic sheet with the anterior surface facing up.Now, open the 3D scanner software application on the laptop's desktop. Click on the 3D scanner icon on the right side of the screen and select the New Work button. Using an easy-to-understand naming convention, create a new folder.To initiate the texture scanning process, select Texture Scan from the menu and leave the Open global markers file section blank. Now, navigate to the left side of the screen and select HDR off. Select the on option for With Turntable.Set Align mode to Turntable Coded Targets, Turntable Steps to eight, Turntable Speed to 10, and Turntable Turns to one turn. Adjust the brightness slider bar to increase exposure on the specimen's darker surfaces. Now click the triangle play button labeled Start Scan on the right hand toolbar, or press the space bar to start the first round of scanning.Once initiated, wait for the platform to complete all eight rotations. Then rotate the scanned image to inspect for any data captured outside the designated green dots on the screen or for any clear artifacts. If the scan is satisfactory, click on the check mark located on the right side of the edit screen to proceed to the next phase of the scan.In case any artifact is detected, hold down the shift key and use the cursor to encircle the artifact outside the intended scan area. Watch for a red circle to manifest around the unwanted artifact. Then click on the Delete data button marked by a garbage can icon located on the right hand toolbar.To initiate the manual alignment, press the Align button, represented by a puzzle piece icon on the right hand toolbar. Click and drag one set of scan data into each alignment frame. Place group one in the fixed box and group two in the floated box.Use the right-click function to orient the two halves of the scan, with one side displaying the specimen's exterior and the other showcasing its interior. Align the two halves so their silhouettes match when superimposed. Use the middle scroll button on the mouse to zoom in and out on the specimen.Identify three distinct landmarks on each set of scan data visible in both sets, serving as alignment points. To select corresponding alignment points, press shift and left-click on the first of three chosen points in each group of data. After selecting two corresponding points, observe a red dot appearing at the selected positions.Check the alignment result in the larger pane beneath the two halves. If the scan is well-aligned, move forward to optimization. To redo the selection of alignment points, press the control key plus Z to undo previous selections, or click on the X box in the top right corner of each pane.Upon completion, export the model in both 3mf and obj file formats. Save the files in the folder created at the start of the scanning process.

Research

JoVE Journal

Medicine

After oncologic resection of malignant tumors, specimens are sent to pathology for processing to determine the surgical margin status. These results are ...