Mesenchymal tumours of the gastrointestinal tract

Non-gastrointestinal stromal tumor, mesenchymal neoplasms of the gastrointestinal tract: a review of tumor genetics, pathology, and cross-sectional imaging findings

There is a diverse group of non-gastrointestinal stromal tumor (GIST), mesenchymal neoplasms of the gastrointestinal (GI) tract that demonstrate characteristic pathology and histogenesis as well as variable imaging findings and biological behavior. Recent advancements in tumor genetics have unveiled specific abnormalities associated with certain tumors, influencing their molecular pathogenesis, biology, response to treatment, and prognosis. Notably, giant fibrovascular polyps of the esophagus, identified through MDM2 gene amplifications, are now classified as liposarcomas. Some tumors exhibit distinctive patterns of disease distribution. Glomus tumors and plexiform fibromyxomas exhibit a pronounced affinity for the gastric antrum. In contrast, smooth muscle tumors within the GI tract are predominantly found in the esophagus and colorectum, surpassing the incidence of GISTs in these locations. Surgical resection suffices for symptomatic benign tumors; multimodality treatment may be necessary for frank sarcomas. This article aims to elucidate the cross-sectional imaging findings associated with a wide spectrum of these tumors, providing insights that align with their histopathological features.

Solitary Glomus Tumor on the Base of the Right Thumb: A Rare Case Report and a Literature Review from Saudi Arabia

A glomus tumor (GT) is a rare and usually benign tumor that originates from the glomus body, which is involved in thermoregulation in the skin. Solitary or multiple, digital or extra-digital, these cutaneous tumors can be benign or malignant. This report describes the diagnosis and surgical management of a solitary glomus tumor at the base of the right thumb in a young Sudanese woman. The diagnosis of glomus tumor was confirmed by medical history, sonographic findings and histopathological report. The lesion was excised via direct complete excision under local anesthesia, resulting in a complete resolution of symptoms. Owing to its high sensitivity level, the use of ultrasound is appropriate to evaluate a lesion suspected to be a glomus tumor. A clinician needs to take into consideration the likelihood of glomus tumors when assessing a patient who has a skin lesion on fingers, toes, or extra-digital area, with pain triggered by temperature changes, pressure, or touch. Additionally, this report includes a review of recent globally reported cases of glomus tumor in the hand to highlight the distinctiveness of this report in context to its atypical location in the area of the thenar eminence and underscoring it as a unique report of its kind from Saudi Arabia.

A 65-Year-Old Man Presenting to the Emergency Department with Gastric Hemorrhage Caused by a Glomus Tumor

BACKGROUND Glomus tumor is a benign but rapidly growing mesenchymal tumor that is a rare in the gastrointestinal tract, can be locally invasive due to its rapid growth, and can result in perforation of a viscus. We report a 65-year-old man presenting as an emergency with gastric hemorrhage and gastric glomus tumor. CASE REPORT A 65-year-old man came to our hospital for a life-threatening upper digestive hemorrhage. The preoperative examinations (digestive endoscopy without sampling of biopsy fragments and contrast-enhanced computer tomography) led to the presumptive diagnosis of gastrointestinal stromal tumor. Wedge resection of the gastric wall was performed. The histopathological examinations revealed a proliferation of round-oval cells of medium size with a solid disposition and in nests. This proliferation dissected the muscular tunic and caused ulceration of the gastric mucosa. Immunohistochemical tests confirmed the diagnosis of glomus tumor and excluded other diagnoses (neuroendocrine tumor or gastrointestinal stromal tumor). The postoperative evolution was favorable, and at the time of discharge, the biochemical test values normalized. CONCLUSIONS Pathologists are faced with a challenging task due to the deceptive appearance that can be presented by such a rare tumor. Histopathological and immunohistochemical examinations are essential in achieving a precise diagnosis and assessing the biological potential of the glomus tumor. Even if it is a benign tumor, the clinical picture it causes can still be a major risk to the patient's life. Consequently, ensuring effective case management becomes crucial, as it requires a thorough comprehension of all conditions encompassed in the differential diagnosis.

Classification of GIST and other benign gastric tumors based on minimally invasive surgical strategy

PURPOSE

Gastrointestinal mesenchymal tumors (GMTs) include malignant, intermediate malignancy, and benign lesions. The aim is to propose a new surgical classification to guide the intraoperative minimally invasive surgical strategy in case of non-malignant GMTs less than 5 cm.

METHODS

Primary endpoint is the creation of a classification regarding minimally invasive surgical technique for these tumors based on their gastric location. Secondary endpoint is to analyze the R0 rate and the postoperative morbidity and mortality rates. Tumors were classified in two groups based on their morphology (group A: exophytic, group B: transmural/intragastric). Each group is then divided based on the tumor location and consequently surgical technique used in subgroup: AI (whole stomach area) and AII (iuxta-cardial and pre-pyloric areas) both for the anterior and posterior gastric wall; BIa (greater curvature on the anterior and posterior wall), BIb (lesser curvature on the anterior wall); BII (iuxta-cardial and pre-pyloric area in the anterior and posterior wall, including the lesser curvature on the posterior wall).

RESULTS

Forty-two patients were classified and allocated in each subgroup: 17 in AI, 2 in AII, 5 in BIa, 3 in BIb, and 15 in BII. Two postoperative Clavien-Dindo I complications (4.8%, subgroup BIa and BIb) occurred. One patient (2.4%, subgroup AI) underwent reintervention due to R0 resection.

CONCLUSIONS

This classification proved to be able to classify gastric lesions based on their morphology, location, and surgical treatment, obtaining encouraging perioperative results. Further studies with wider sample of patients are required to draw definitive conclusions.

A national cancer database analysis of the clinicopathologic characteristics and outcomes of appendiceal malignant mesenchymal tumors

The present study aimed to assess the characteristics and outcomes of appendiceal malignant mesenchymal tumors. This was a retrospective case-series study of patients with appendiceal malignant mesenchymal tumors in the national cancer database (2005-2019). The main outcomes were overall survival (OS) and short-term mortality. 53 patients (40 GISTs and 13 sarcomas) were included. 92.6% of GIST patients had stage I disease and 76.9% of GISTs were ≤2 cm. Most appendiceal GISTs were treated with appendectomy or partial colectomy whereas half of patients with appendiceal sarcoma underwent hemicolectomy or subtotal colectomy. Only one short-term mortality was recorded in the sarcoma group. One-third of patients with sarcoma had positive surgical margins versus 5.1% of patients with GISTs. GIST patients had longer median OS (117.1 vs 54.8 months) than sarcoma patients.

Updates in the diagnosis and management of small-bowel tumors

Small-bowel tumors represent a rare entity comprising 0.6% of all new cancer cases in the US, and only 3% of all gastrointestinal neoplasms. They are a heterogenous group of neoplasms comprising of about forty different histological subtypes with the most common being adenocarcinoma, neuroendocrine tumors, stromal tumors and lymphomas. Their incidence has been reportedly increasing over recent years, partly owing to the advances and developments in the diagnostic modalities. Small-bowel capsule endoscopy, device assisted enteroscopy and dedicated small-bowel cross-sectional imaging are complimentary tools, supplementing each other in the diagnostic process. Therapeutic management of small-bowel tumors largely depends on the histological type and staging at diagnosis. The aim of the present review article is to discuss relevant advances in the diagnosis and management of small-bowel tumors.

Preoperative endoscopy and pathology report of the specimen to be recommended in sleeve gastrectomy?

Objective

Preoperative upper gastrointestinal endoscopy (UGIE) and postoperative histopathological examination (HPE) of resected specimens are still controversial issues in bariatric surgery.

Methods

A retrospective review of prospectively collected laparoscopic sleeve gastrectomies (SG) performed at our institution for morbid obesity was carried out. All patients underwent pre-operative UGIE with biopsy, post-operative HPE and conventional post-operative follow-up.

Results

From January 2019 through January 2021 we performed a total of 501 laparoscopic SG. A total of 12 (2.4%) neoplasms were found, 2 evident at preoperative UGIE, 4 detected during operation, and 6 at HPE. Eight of these 12 cases had some malignant potential and 5 would not have been detected without HPE of the specimen. The most significant unexpected case was a fundic gland type adenocarcinoma in a 64-year-old female with severe obesity.

Conclusion

On the basis of our clinical experience, we recommend both preoperative endoscopic assessment and postoperative HPE of the specimen to provide the best available treatment to these patients.

Emerging Targeted Therapeutic Strategies to Overcome Imatinib Resistance of Gastrointestinal Stromal Tumors

Gastrointestinal stromal tumors (GISTs) are the most common malignant mesenchymal neoplasms of the gastrointestinal tract. The gold standard for the diagnosis of GISTs is morphologic analysis with an immunohistochemical evaluation plus genomic profiling to assess the mutational status of lesions. The majority of GISTs are driven by gain-of-function mutations in the proto-oncogene c-KIT encoding the tyrosine kinase receptor (TKR) known as KIT and in the platelet-derived growth factor-alpha receptor (PDGFRA) genes. Approved therapeutics are orally available as tyrosine kinase inhibitors (TKIs) targeting KIT and/or PDGFRA oncogenic activation. Among these, imatinib has changed the management of patients with unresectable or metastatic GISTs, improving their survival time and delaying disease progression. Nevertheless, the majority of patients with GISTs experience disease progression after 2-3 years of imatinib therapy due to the development of secondary KIT mutations. Today, based on the identification of new driving oncogenic mutations, targeted therapy and precision medicine are regarded as the new frontiers for GISTs. This article reviews the most important mutations in GISTs and highlights their importance in the current understanding and treatment options of GISTs, with an emphasis on the most recent clinical trials.

Gastrointestinal Stromal Tumor Recurrence Presenting as a Small Bowel Obstruction: A Case Report

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the alimentary tract in adults. The most common site is the stomach, followed by the small intestine. The clinical presentation varies from an incidental finding in asymptomatic patients to a large palpable mass causing complications such as bowel obstruction or viscus perforation. The best imaging modality is a CT scan of the abdomen. Treatment is determined by the size and location of the GISTs. Surgical intervention is considered for resectable tumors, while tyrosine kinase inhibitor therapy is considered for irresectable, metastatic, or recurrent GISTs. In this case report, we present a 30-year-old female who is a known case of gastric GIST and liver metastases. She presented to the emergency department with intestinal obstruction secondary to a recurrent GIST abdominal mass and underwent emergency laparotomy for mass resection. Following surgery, the patient developed aspiration pneumonia, which was treated with proper antibiotics. She was discharged in stable clinical condition with a recommendation to start alternative tyrosine kinase therapy. GISTs are difficult to diagnose preoperatively, as most patients are asymptomatic, and they may present with complications, as in our case, a small bowel obstruction. A proper imaging modality will guide the physician toward the diagnosis, but the final diagnosis will be achieved by biopsy. The diagnosis may be challenging, as small bowel obstruction has many causes, although GISTs should be kept in mind as one of the deferential diagnoses.

Giant esophageal liposarcoma with squamous cell carcinoma resected via the cervical approach: a case report

Background

Liposarcoma is one of the most common soft tissue sarcomas, but is extremely rarely found in the esophagus. There have been no reports of esophageal liposarcoma together with superficial carcinoma of the esophagus. Here, we report a patient who underwent complete resection of esophageal liposarcoma with carcinoma via a cervical approach.

Case presentation

A 66-year-old man was diagnosed with an esophageal tumor 11 years ago, but he left it untreated. He presented to our hospital with progressive dysphagia and appetite loss since the previous year. Esophagogastroduodenoscopy (EGD) showed a large pedunculated submucosal tumor (SMT) originating at the esophageal entrance, extending to the gastroesophageal junction. Additionally, there was a superficial carcinoma on the surface of the SMT, 30 cm from the incisor teeth. Three-dimensional computed tomography (3D-CT) showed a giant elongated intraluminal tumor extending downwards from the cervical esophagus. We diagnosed a giant esophageal polyp accompanied by a superficial carcinoma and performed tumor resection via a cervical approach. The excised specimen consisted of a 23.0 × 8.5 cm polypoid mass. The final diagnosis by histopathological and immunohistochemical examination was well-differentiated liposarcoma and esophageal squamous cell carcinoma. He was discharged on postoperative day 14 with drastic improvement in his swallowing ability.

Conclusion

We reported an extremely rare case of esophageal liposarcoma together with esophageal squamous cell carcinoma that was successfully resected through a small cervical incision.

Bacterial Involvement in Progression and Metastasis of Colorectal Neoplasia

While the gut microbiome is composed of numerous bacteria, specific bacteria within the gut may play a significant role in carcinogenesis, progression, and metastasis of colorectal carcinoma (CRC). Certain microbial species are known to be associated with specific cancers; however, the interrelationship between bacteria and metastasis is still enigmatic. Mounting evidence suggests that bacteria participate in cancer organotropism during solid tumor metastasis. A critical review of the literature was conducted to better characterize what is known about bacteria populating a distant site and whether a tumor depends upon the same microenvironment during or after metastasis. The processes of carcinogenesis, tumor growth and metastatic spread in the setting of bacterial infection were examined in detail. The literature was scrutinized to discover the role of the lymphatic and venous systems in tumor metastasis and how microbes affect these processes. Some bacteria have a potent ability to enhance epithelial–mesenchymal transition, a critical step in the metastatic cascade. Bacteria also can modify the microenvironment and the local immune profile at a metastatic site. Early targeted antibiotic therapy should be further investigated as a measure to prevent metastatic spread in the setting of bacterial infection.

Massive Digestive Hemorrhagia Revealing a Gastro-Intestinal Stromal Tumor of the Jejunum

Gastrointestinal stromal tumors (GISTs) are mesenchymal tumors that originate from Cajal cells located in different sites of the digestive system. They may occur in the entire gastrointestinal tract. They are diagnosed on the basis of the identification of c-kit-positive cells. We report a case of a stromal tumor of the jejunum revealed by a massive digestive hemorrhagia. Surgical resection is the basis of the treatment of GISTs. Imatinib, a tyrosine kinase inhibitor, is a beneficial treatment after surgical resection of high-risk GISTs.