A Case of Liver Metastasis from Small Intestinal Gastrointestinal Stromal Tumor 25 Years after Surgery including Autopsy Findings

18F-FDG PET/CT and MR imaging features of liver metastases in gastrointestinal stromal tumors: a cross-sectional analysis

BACKGROUND

Early detection of gastrointestinal stromal tumor (GIST) liver metastases is crucial for the management and prognosis. In our experience, GIST liver metastases can display hypermetabolism on ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) and marked enhancement on magnetic resonance imaging (MRI), which are uncommon in other tumors before treatment. Most literature focus on the imaging evaluation, prognosis after treatment and less is known about imaging features on both imaging methods before treatment. This study analyzes the imaging features of newly diagnosed GIST liver metastases on ¹⁸F-FDG PET/CT and MRI, with goal of improving diagnostic accuracy.

METHODS

This retrospective study included 55 patients with pathological or radiographical confirmed GIST liver metastases who underwent PET/CT (n=29), MRI (n=22), or both methods (n=4). PET/CT and MRI interpretation including lesion's morphologic features, number, density or signal intensity, hemorrhage, cystic changes or necrosis, maximum standardized uptake value (SUV_max) of liver metastases and liver background on PET imaging, degree and pattern of enhancement on MRI were obtained by two experienced nuclear medicine physicians and two radiologists respectively. Data are presented as numbers, percentages, means ± standard deviations or median (interquartile range). The correlation between diameter and SUV_max of metastases, and primary tumor SUV_max and synchronous liver metastases SUV_max were analyzed by Spearman's rank test.

RESULTS

On PET/CT visual analysis, 38.9%, 23.9%, and 37.2% of lesions showed significant hypermetabolism, slightly higher metabolism, and equal or lower metabolism than liver, respectively. There was a weak correlation between the diameter and SUV_max of liver metastases (r_s =0.370, P<0.001), and a moderate correlation between SUV_max of synchronous liver metastases and the primary tumors (r_s =0.492, P<0.001). On contrast-enhanced MRI, 90.8% of lesions showed heterogeneous enhancement in the arterial phase with the variable presentation, and 74.3% had different enhancement patterns between margins and intratumoral parenchyma.

CONCLUSIONS

Liver lesions in GIST displaying significant, slight hypermetabolism on ¹⁸F-FDG PET/CT, marked or heterogeneous gradual enhancement within the intratumoral parenchyma with ring-like enhancement on MRI may denote the diagnosis of liver metastasis. However, GIST liver metastases may also display equal or lower metabolism than liver parenchyma on PET, making small lesions more difficult to diagnose.

Clinical Research on Gastrointestinal Surgery Based on Smart Medicine

Smart medical technology uses the medical information platform, with the help of current technical means, so that the information between medical staff and medical equipment can be shared. The combination of current technology and the medical field has become the norm. In the future, more artificial intelligence technologies will be incorporated in the medical field to promote the development of medical undertakings. At present, the information on the Internet is very large and complex, and general search engines often do not have knowledge in certain professional fields and can only perform shallow keyword searches, so it is difficult to meet people's medical diagnostic needs. Smart medical technology can solve the problem of these needs. Surgery, commonly known as operation, refers to the process of entering the body to change the condition of the disease through technical means and under the guidance of professionals. Earlier operations only performed cutting on the body surface. With the continuous maturity of surgical operations, operations can now be performed on any part, but manual operations are still the main one. In addition to manual surgery, there are many machine surgeries, such as laser surgeries. Clinical research takes the diagnosis and treatment of diseases as the main content, takes patients as the research object, and is a scientific research activity involving multiple personnel. This article aimed to study the clinical research of gastrointestinal surgery based on smart medicine and hoped to use smart medical technology to improve the clinical research level of gastrointestinal surgery and provide technical support for surgery. This study proposes to apply natural language processing technology to the medical field, build an intelligent diagnostic auxiliary system, and use the existing medical record data to realize the corresponding medical auxiliary function. The research measures and analyzes the basic information of medical students, the incidence of functional gastrointestinal disease, the incidence of common symptoms of functional gastrointestinal disease, and the differential distribution of various symptoms in different professions, genders, and ages. The experimental results of this article show that there are 27 cases of gastrointestinal bleeding, accounting for 18%; 10 cases of dysphagia, accounting for 7%; 78 cases of abdominal pain and bloating, accounting for 53%; and 19 cases of melena, accounting for 13%. Abdominal pain and bloating are the most common clinical manifestations of the gastrointestinal tract and require more attention.