Primary gastrointestinal lymphoma: spectrum of imaging findings with pathologic correlation

Insights into gastrointestinal manifestation of human immunodeficiency virus: A narrative review

Human immunodeficiency virus (HIV) modifies CD4-positive cells, resulting in immunodeficiency and a wide range of gastrointestinal (GI) manifestations. The burden of HIV-related GI illnesses has significantly evolved with the widespread use of antiretroviral therapy (ART). While ART has effectively reduced the occurrence of opportunistic infections, it has led to an increase in therapy-related GI illnesses. Common esophageal conditions in HIV patients include gastroesophageal reflux disease, idiopathic esophageal ulcers, herpes simplex virus, cytomegalovirus (CMV), and candidal esophagitis. Kaposi’s sarcoma, a hallmark of acquired immunodeficiency syndrome, may affect the entire GI system. Gastritis and peptic ulcer disease are also frequently seen in patients with HIV. Diarrhea, often linked to both opportunistic infections and ART, requires careful evaluation. Bloody diarrhea, often a sign of colitis caused by bacterial infections such as Shigella or Clostridium difficile, is prevalent. Small bowel lymphoma, although rare, is increasing in prevalence. Anorectal disorders, including proctitis, fissures, and anal squamous cell carcinoma, are particularly relevant in homosexual men, underlining the importance of timely diagnosis. This review comprehensively explores the epidemiology, pathogenesis, and treatment considerations for the various GI disorders associated with HIV, highlighting the importance of accurate diagnosis and effective treatment to improve outcomes for HIV-infected patients.

Diffusely Infiltrative Small Bowel Disease

Multiple infiltrative disorders can affect the small bowel, often resulting in diffuse small bowel wall thickening. These infiltrative disorders can manifest owing to various factors such as an influx of immunologic or neoplastic cells or the accumulation of substances within one or more layers of the intestinal wall. Although there can be considerable overlap in the appearances of infiltrative diseases on cross-sectional images, a comprehensive understanding of more specific ancillary imaging features and clinicopathologic correlation can substantially narrow the differential diagnosis. The radiologist can be instrumental in synthesizing the clinical and imaging information and guiding subsequent workup. The authors present a comprehensive review of the infiltrative disorders that commonly involve the small bowel. These disorders are organized on the basis of their pathophysiologic features, with multiple illustrative case examples to enhance understanding of these entities. CT and MRI are currently the most commonly used imaging modalities for evaluating small bowel disorders, and this review is focused on these two modalities. Detailed information regarding the pathologic features, clinical presentation, and imaging findings of these infiltrative disorders is provided to aid radiologists in recognizing and differentiating these conditions. ©RSNA, 2024.

Burkitt's lymphoma revealed by intestinal obstruction: A case report

Intestinal obstruction is a surgical emergency frequently encountered in routine practice, usually caused by abdominal adhesions. Although extra nodal lymphoma is most often localized in the gastrointestinal tract and may be responsible for intestinal obstruction, Burkitt's lymphoma is a very rare cause in adults. We report a case of Burkitt's lymphoma mimicking an intestinal obstruction in a 48-year-old adult who presented with an obstructive syndrome and altered general condition. Imaging and anatomopathological examination after immunohistochemical analysis concluded to a multi-systemic Burkitt's lymphoma. Chemotherapy was immediately started with complete remission.

Primary diffuse large B-cell lymphoma of the cecum

When found in the cecum or rectosigmoid junction, primary colorectal B-cell lymphoma is a rare malignant non-Hodgkin's lymphoma often associated with an unfavorable prognosis. Due to the nonspecific clinical symptoms, these uncommon tumors are often left undefined or misdiagnosed, resulting in delays in treatment and adverse patient outcomes. Contrast-enhanced computed tomography is the most commonly used medical imaging process for primary colorectal lymphoma, but due to the rarity of this disorder, accurate imaging diagnosis remains a clinical challenge. In this article, we report the case of a 70-year-old male who was diagnosed with primary B-cell lymphoma of the cecum. We focus on improving diagnosis through the utilization of radiological imaging modalities, particularly computed tomography (CT) and fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (18-F-FDG PET/CT). While imaging modalities are important in recognizing colonic lymphomas, there are no pathognomonic imaging features for lymphoma; therefore, biopsy remains necessary for diagnostic confirmation.

MR Enterography in Ulcerative Colitis: Beyond Endoscopy

Ulcerative colitis (UC) is a chronic idiopathic inflammatory bowel disease (IBD) that progressively affects mucosa and submuccosa of the colon and rectum in a continual pattern. In comparison, Crohn disease (CD), the other type of IBD, is a chronic transmural inflammatory disorder that can involve any part of the gastrointestinal tract. MR enterography (MRE) has emerged as an important imaging modality for the diagnosis and detection of disease activity and complications in CD, with comparable results to those of endoscopy. But MRE has been underused for assessment of UC in recent years, and clinicians heavily rely on endoscopic findings for management of UC. Despite UC being considered an endoscopically assessable disease, MRE can provide useful information beyond that obtained with endoscopy about mural or extramural abnormalities, inaccessible parts of the colonic lumen, associated extraintestinal diseases, and superimposed pathologic conditions. Moreover, endoscopy might be contraindicated in some clinical settings due to the risk of colonic perforation. In addition to depicting the features of UC activity in different phases, MRE demonstrates findings of disease chronicity that cannot be achieved with endoscopy, particularly in a patient with colitis of unknown cause. The valuable diagnostic role of MRE to exclude undiagnosed CD in patients with UC who have refractory disease or those with postproctocolectomy complications is also emphasized. Radiologists can play a crucial role in the management of UC with MRE by addressing what is beyond endoscopy. ©RSNA, 2023 Test Your Knowledge questions are available in the supplemental material.

MR imaging findings of ovarian lymphoma: differentiation from other solid ovarian tumors

PURPOSE

To evaluate magnetic resonance imaging (MRI) findings for distinguishing ovarian lymphomas from other solid ovarian tumors.

METHODS

This retrospective multicenter study included 14 women (median age, 46.5 years; range, 26-81 years) with surgically proven ovarian lymphoma and 28 women with solid ovarian tumors other than lymphoma. We conducted a subjective image analysis of factors including laterality, shape, composition, T2 signal intensity (SI), heterogeneity, diffusion restriction, enhancement, and presence of peripheral follicles. A generalized estimating equation was used to identify MRI findings that could be used to distinguish ovarian lymphomas from other solid ovarian tumors. Diagnostic performance of the identified MRI findings was assessed using the area under the receiver-operating characteristic curve (AUC).

RESULTS

Ovarian lymphoma more frequently showed homogeneous high SI on T2-weighted imaging (81.8% vs. 19.4%, P < 0.001) and peripheral ovarian follicles (40.9% vs. 8.3%, P = 0.01) than other ovarian solid tumors did. Bilaterality, shape, size, diffusion restriction, and enhancement did not differ between the two groups (P > 0.05 for all). Homogeneous high SI on T2-weighted imaging was the only independent MRI finding (OR = 15.19; 95% CI 3.15-73.33; P = 0.001) in the multivariable analysis. Homogeneous high SI on T2-weighted imaging yielded an AUC of 0.82 with a sensitivity of 81.8% and specificity of 80.6% in distinguishing ovarian lymphomas from other solid ovarian tumors.

CONCLUSION

Homogeneous high signal intensity on T2-weighted imaging was helpful in distinguishing ovarian lymphomas from other solid ovarian tumors. Peripheral ovarian follicles might be an additional clue that suggests a diagnosis of ovarian lymphoma.

Typical and Atypical Imaging Features of Malignant Lymphoma in the Abdomen and Mimicking Diseases

Malignant lymphoma typically presents with homogeneous enhancement of enlarged lymph nodes without internal necrotic or cystic changes on multiphasic CT, which can be suspected without invasive diagnostic methods. However, some subtypes of malignant lymphoma show atypical imaging features, which makes diagnosis challenging for radiologists. Moreover, there are several lymphoma-mimicking diseases in current clinical practice, including leukemia, viral infections in immunocompromised patients, and primary or metastatic cancer. The ability of diagnostic processes to distinguish malignant lymphoma from mimicking diseases is necessary to establish effective management strategies for initial radiological examinations. Therefore, this study aimed to discuss the typical and atypical imaging features of malignant lymphoma as well as mimicking diseases and discuss important diagnostic clues that can help narrow down the differential diagnosis.

Imaging Features of Gastrointestinal Neoplasms Complicating Inflammatory Bowel Diseases

Inflammatory bowel diseases (IBD) are chronic inflammatory diseases affecting the gastrointestinal (GI) tract. Patients with IBD, besides other non-neoplastic complications, are also at increased risk of GI malignancies such as colorectal cancer, small bowel adenocarcinoma and lymphoma. The principal purpose of imaging in patients with IBD to assess complications and to stage a clinically known cancer. In addition, the goal of imaging has expanded to include the diagnosis of GI malignancies in clinical situations where colonoscopy cannot be performed or is incomplete. In addition, imaging allows the detection of cancers in patients where the development of either disease-related or treatment-related neoplasia is clinically suspected. The purpose of this review is to present the different imaging techniques used to detect GI malignancies in IBD patients and describe the radiological appearances of GI malignancies in IBD patients.

Delayed Metastatic Cholangiocarcinoma to the Stomach With Imaging Characteristics Resembling Gastrointestinal Stromal Tumor: A Case Report and Review of the Literature

Intrahepatic cholangiocarcinoma (ICC) is a relatively rare subtype of cholangiocarcinoma, and there has been an increasing incidence of ICC in Western countries in recent years. Surgical resection is the most effective treatment for ICC. However, overall outcomes are extremely poor given that most patients are diagnosed at an advanced stage, and postoperative ICC recurrence is still very high despite hepatic resection. We report a case of metastatic ICC to the stomach presenting after resection of the original tumor, with imaging characteristics highly resembling gastrointestinal stromal tumor (GIST) on imaging. Reported cases of metastatic ICC to the liver are sparse. Given that there is a significant difference in the survival rate between metastatic cholangiocarcinoma and other tumors arising from the gastrointestinal tract, including GISTs, it is important to delineate the differences via imaging features. We further discuss the imaging characteristics of intrahepatic ICC, comparing and contrasting it to other gastric tumors.

Isolated gastric involvement of recurrent Hodgkin lymphoma: a case report and review of the literature

BACKGROUND

Although the gastrointestinal tract is one of the most common sites for extranodal lymphoma, gastrointestinal lymphoma is a rare disease that is almost exclusively non-Hodgkin lymphoma.

CASE PRESENTATION

We present a rare condition of Hodgkin lymphoma relapse after 12 years as isolated gastric involvement caused massive gastrointestinal bleeding in a 34-year-old Iranian woman. According to the result of the upper endoscopy, laparotomy was performed, and a large mass in the upper part of the fundus, alongside the esophagogastric junction, was seen, so gastrectomy was performed.

CONCLUSION

All symptoms and paraclinical findings for gastrointestinal Hodgkin lymphoma are nonspecific. Therefore, the preoperative diagnosis is challenging. It seems that surgery is a suitable diagnostic and therapeutic method in this field.

FDG PET/CT in a Case of Esophageal Extranodal NK/T-Cell Lymphoma, Nasal Type

ABSTRACT

Lymphoma involving the esophagus is rare. We describe FDG PET/CT findings in a case of extranodal NK/T-cell lymphoma, nasal type involving the larynx, hypopharynx, and cervical and upper thoracic esophagus. The esophageal tumor showed segmentally increased FDG uptake mimicking esophagitis. This case indicates that esophageal lymphoma should be included in the differential diagnosis of the hypermetabolic esophageal diseases.

Spontaneous perforation of primary gastric diffuse large B-cell lymphoma

Primary gastric malignant lymphoma is a rare tumor. The complications associated with lymphoma are perforation, bleeding, or upper gastrointestinal stricture. While it is well known that perforations in gastric lymphoma often occurs during chemotherapy, spontaneous perforation is extremely rare in patients who did not receive chemotherapy. This complication requires a surgical treatment.

Gastric perforation secondary to T-cell lymphoma

Introduction

Malignant primary lymphoma represents only 1%-5% of all gastric tumours. Spontaneous gastric perforation in the absence of chemotherapy in these cases is extremely rare. The vast majority of primary gastric lymphomas have a B-cell phenotype that originates from mucosa-associated lymphoid tissue and primary gastric lymphomas with a T-cell phenotype are rarely reported. This report describes a case of a primary gastric T-cell malignant lymphoma associated to spontaneous perforation and peritonitis.

Case presentation

An 80-year-old woman referring 24 hours of abdominal pain associated to cognitive impairment consulted to our Emergency Department. Her past medical history revealed smoking, hypothyroidism, dilated cardiomyopathy, hypertension, celiac disease with poor adherence to gluten-free diet and a Non-Hodgkin T cell lymphoma associated to enteropathy in 2010. At physical examination, she presented with tachycardia, hypotension and abdominal tenderness. Lab test revealed low red cell count and an abdomen computed tomography scan showed pneumoperitoneum secondary to a large gastric perforation located in the anterior wall of the antrum. Urgent surgery was performed. At exploratory laparoscopy, a 5 cm perforation of the anterior wall of prepyloric antrum was observed associated to a 4-quadrant peritonitis. Conversion to open surgery was decided to perform an open antrectomy and Billroth II gastro-jejunostomy. The patient was transferred to ICU after surgery under mechanical respiratory assistance for closed monitoring but evolved with a cardiogenic shock and deceased on the first postoperative day. The final histopathological and immunohistochemical analysis reported enteropathy-associated T-cell lymphoma of gastric localisation with concomitant celiac disease.

Discussion

We present a rare case of a patient with a history of celiac disease who developed a gastric perforation secondary to an enteropathy-associated T-cell lymphoma of gastric localisation. To the best of authors' knowledge, there have been reported less than 30 cases of spontaneous perforation of gastric lymphoma in the absence of chemotherapy in the last 35 years. Malignant gastric lymphoma, accounting only for 1% of primary gastric malignancies, is usually a diffuse large B-cell lymphoma. Incidence of perforation of gastric lymphomas in patients receiving chemotherapy rounds 0.9%-1.1%. However, it is a rare condition in patients not receiving chemotherapy.

Conclusion

This is a rare case of a patient with an enteropathy-associated T-cell lymphoma of gastric localisation, who developed a spontaneous gastric perforation in the absence of chemotherapy. Despite it is a rare condition, it must be suspected in patients with a history of lymphoma in the context of acute abdominal pain.

Radiologic Review of Small Bowel Malignancies and Their Mimicking Lesions

Because of their small size, small bowel malignancies are often easily missed when radiologists read CT images, which can lead to errors in the normal small bowel due to their similar enhancement to the small bowel or non-specific enhancement. In addition, small bowel malignancies are sometimes mistaken for masses of other origins, such as the uterus, rectum, or omentum. In this article, we describe various small-bowel malignancies, their mimicking lesions and the typical and atypical features on CT imaging along with their clinical manifestations.

Surgical management of monomorphic epitheliotropic intestinal T-cell lymphoma followed by chemotherapy and stem-cell transplant: A case report and review of the literature

BACKGROUND

Monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL) is a rare and rapidly progressive intestinal T-cell non-Hodgkin lymphoma associated with a very poor prognosis and a median survival of 7 mo. Advances in the identification of MEITL over the last two decades have led to its recognition as a separate entity. MEITL patients, predominantly male, typically present with vague and nonspecific symptoms and diagnosis is predominantly confirmed at laparotomy. Currently, there are no standardized treatment protocols, and the optimal therapy remains unclear.

CASE SUMMARY

We report a case of MEITL that was initially considered to be gastrointestinal stromal tumor (GIST) and Imatinib was administered for one cycle. The 62-year-old man presented with abdominal pain, abdominal distension, and weight loss of 20 pounds. Within 2 wk, the size of the mass considerably increased on computed tomography scans. The patient underwent surgery followed by chemotherapy with CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) and stem-cell transplant. A correct diagnosis of MEITL was established based on postoperative pathology. Immunophenotypically, the neoplastic cells fulfilled the diagnostic criteria for MEITL as they were CD3⁺, CD4⁺, CD8⁺, CD56⁺, and TIA-1⁺.

CONCLUSION

Given that MEITL has no predisposing factor and presents with vague symptoms with rapid progression, the concomitant presence of abdominal symptoms and B symptoms (weight loss, fever, and night sweats) with hypoalbuminemia, anemia, low lymphocytic count and endoscopic findings of diffuse infiltrating type lesions should alert physicians to this rare disease, especially when it comes to Asian patients. Immediate laparotomy should then be carried out followed by chemotherapy and stem-cell transplant.

An unusual ileocecal tumor

We report the case of diffuse large B-cell lymphoma (DLBCL) with a fistula from the ileum to the cecum. A 57-year-old male came to the hospital complaining of abdominal pain. He underwent an abdominal computed tomography with contrast, which showed full-thickness wall thickening at the ileocecal region. He underwent a lower gastrointestinal endoscopy. No tumor was found at the ileocecal valve, and macroscopic findings were normal. The scope was advanced to the cecum, an additional outpouching was found. The outpouching appeared to be an ileocecal fistula. The diagnosis was DLBCL.

Complications of lymphoma in the abdomen and pelvis: clinical and imaging review

Involvement of the abdomen and pelvis is common in lymphoma. Nodal and extranodal abdominal and pelvic lymphoma may present with various complications. Complications are most common in high-grade lymphomas, especially diffuse large B-cell lymphoma. Complications may occur as the initial manifestation of lymphoma, during treatment course, or late following complete disease remission. Most complications are associated with worse prognosis and increased mortality. Imaging is essential in evaluation of disease extent and diagnosis of complications. Therefore, radiologists should be familiar with the clinical context and imaging features of abdominal and pelvic lymphoma complications. We provide a comprehensive, organ system-based approach, and clinical and imaging review of complications of abdominal and pelvic lymphoma along with radiologic images of illustrated cases of the most commonly encountered complications.

A lumpy bumpy stomach: The more the murkier

This report describes the radiological and endoscopic findings in a 54-year-old male who presented with epigastric pain. The patient underwent an upper gastrointestinal (GI) barium study followed by axial imaging, which demonstrated nodular gastric wall thickening. The classic findings of aggressive primary gastric diffuse large B-Cell lymphoma are presented with a brief review differentiating the pathological subtypes, important for patient prognostication and planning of therapy.

Protein Loss Enteropathy as an Initial Presentation of Gastric Epstein–Barr Virus Lymphoma

Protein loss enteropathy (PLE) is a complex disease process that can result in potentially fatal protein losses. Gastrointestinal protein losses usually arise from damage to the gastrointestinal mucosa or from lymphatic obstruction. The goal of management is to identify and treat the underlying causes and maintain normal serum protein levels. Here, we present a patient with diarrhea and generalized edema, with decreased serum albumin and gamma-globulin levels, concerning for protein loss enteropathy. He was ultimately found to be positive for HIV infection, and his stool alpha-1 antitrypsin levels were diagnostic of protein loss enteropathy. His endoscopic and histologic evaluation revealed gastric Epstein–Barr virus-encoded small RNA- (EBER-) positive lymphoma. Though gastrointestinal lymphomas are known to cause PLE, this will be the first documented case of EBER-positive gastric lymphoma presenting with PLE. We hope to bring awareness to this unique presentation to aid in expedient diagnosis and treatment to avoid delays in treatment and potentially fatal outcomes.

Unusual presentation of aggressive high-grade B-cell lymphoma of colonic origin: A case report and review of the literature

Colonic lymphoma is a rare disease. The presented case is unique, being manifested with abrupt onset, including circulatory shock and lactic acidosis as the initial presentation.

Schwannoma in and around the porta hepatis: radiological features in eight cases and literature review

PURPOSE

Schwannomas in and around the porta hepatis (porta hepatic schwannomas) are rare benign tumors easily misdiagnosed as other pathologies, including malignancies. We aimed to evaluate their imaging features on ultrasonography, computed tomography (CT), magnetic resonance imaging (MRI), and ¹⁸F-fluorodeoxyglucose-positron emission tomography/CT (FDG-PET/CT).

METHODS

We performed a multi-institutional retrospective study by reviewing the clinical and imaging findings of pathologically proven eight porta hepatic schwannomas (mean age, 55 years; range, 38-80 years; one male and seven females). Preoperative imaging included three ultrasonography, eight CT, eight MRI, and two FDG-PET/CT.

RESULTS

All patients were asymptomatic. The mean tumor size was 61.9 mm (range, 30-180 mm), and all tumors demonstrated well-defined lesions on ultrasonography and their solid components showed soft tissue attenuation on non-contrast CT. MRI showed two distinct components in all cases: the component with T1-weighted hypointensities and T2-weighted hyperintensities with poor enhancement (suggestive of Antoni B histology); the component with T2-weighted hypointensities with gradually increasing enhancement (suggestive of Antoni A histology), resulting in a heterogeneous pattern on post-contrast CT or MRI (8/8, 100%). The separated deviation of surrounding bile ducts and vessels without obstruction allowed the recognition of extrahepatic localization and their benign nature. A ginger root-like morphology (2/8, 25%) seemed to be suggestive of extension along the Glisson's sheath, although this finding was not seen frequently.

CONCLUSION

Recognizing imaging features such as extrahepatic location, benign nature with internal structures suggestive of Antoni A/B histology, and characteristic tumor extension may provide key diagnostic clues for porta hepatic schwannomas.

Imaging of Bowel Lymphoma: A Pictorial Review

Intestinal lymphoma, although rare, is the second most common extra-nodal site of lymphoma, following stomach. It is usually secondary to systemic involvement and is predominantly of non-Hodgkin's subtype. In addition to the risk factors for lymphomas occurring elsewhere, certain risk factors are specific for intestinal lymphoma. These include enteropathies such as celiac disease and inflammatory bowel disease. Imaging is the cornerstone in the management of intestinal lymphoma. Contrast-enhanced computed tomography or positron emission tomography-computed tomography are the preferred modalities for diagnosis, staging, monitoring response to treatment, and for follow-up evaluation. Bowel lymphomas can have various morphological patterns on imaging; however, certain characteristic features, if present, may prove invaluable in its diagnosis. Hence, it is imperative to be acquainted with the myriad of imaging findings in bowel lymphoma and its complications which may not only help in vivo distinction from other commoner bowel lesions but alter the management accordingly.

Fluoroscopic Evaluation of Duodenal Diseases

The duodenum can be affected by a variety of abnormalities because of its development during embryogenesis and its dual intra- and retroperitoneal location. If small bowel embryogenesis is disturbed, congenital errors occur. Although some congenital variants may be asymptomatic and inconsequential to the patient, other anomalies can result in life-threatening emergencies such as malrotation, leading to midgut volvulus. Many infectious processes affect the duodenum, including duodenal ulcers and opportunistic infection in patients with HIV/AIDS or Crohn disease. Small bowel malignancies are uncommon but important to recognize, because the duodenum can be involved in polyposis syndromes or the development of primary adenocarcinoma, neuroendocrine tumors, lymphoma, and metastasis. Although endoscopy is currently the most used diagnostic method to assess the lumen of the upper gastrointestinal tract, fluoroscopy is a valuable adjunct technique and the study of choice for many diseases, specifically those for which anatomic and functional information is required. Fluoroscopy is also commonly used postoperatively to assess for complications such as obstruction and extraluminal leaks. Compared with endoscopy, fluoroscopy is an inexpensive and noninvasive technique that provides salient anatomic information and allows delineation of the duodenal mucosa and assessment of real-time duodenal motility. The authors examine the broad spectrum of conditions that can involve the duodenum, including congenital, infectious, inflammatory, and neoplastic abnormalities, and review their typical appearances at fluoroscopy. Online supplemental material is available for this article. ^©RSNA, 2022.

A Stromal Tumor Presenting as a Pseudoaneurysmal Dilation of the Small Bowel Mimicking a Lymphoma on FDG PET/CT

ABSTRACT

An 84-year-old woman visited our hospital with hematochezia for 1 month. Abdominal CT and FDG PET/CT showed local thickening of the small intestine, resembling an intestinal aneurysmal dilatation. Thus, a lymphoma was suspected, and surgical resection was performed. The final pathology revealed an exophytic small bowel stromal tumor with perforation, causing pseudoaneurysmal dilation of the small bowel. This case emphasized the importance of considering a small bowel stromal tumor when faced with similar FDG PET/CT findings.

Imaging of Gastric Carcinoma. Part One: Diagnosis and Staging

Gastric cancer is one of the leading causes of death from malignancy. Despite the enormous advancement in medical oncology over the past decade, surgical resection of early tumors remains the most effective treatment. Accurate interpretation of radiologic imaging studies is crucial for staging local disease spread, predicting possible lymphatic involvement, and identifying metastatic disease, thereby guiding management plans. This article reviews imaging patterns of the normal stomach along with appearances of gastric cancer, its local spread patterns and distant metastasis, and also describes key features pertaining to preoperative staging.

En Bloc Resection of Primary Large Esophageal Mucosa-Associated Lymphoid Tissue Lymphoma by Endoscopic Submucosal Dissection: A Case Report

Treatment of mucosa-associated lymphoid tissue (MALT) lymphoma has recently received considerable attention. Here, we report a case of large esophageal MALT lymphoma that was successfully en bloc resected using endoscopic submucosal dissection (ESD). A 77-year-old woman was admitted to our hospital with progressive dysphagia for more than 2 months. Upper gastrointestinal endoscopy revealed a large rounded submucosal mass covered by normal mucosa, located at the lower esophagus. Endoscopic ultrasonography (EUS) showed a well-demarcated hypoechoic mass chiefly located in the esophageal wall, but the layers of the esophageal wall were not clear. ESD was performed for diagnostic and treatment purposes. No complications occurred during or after ESD. The resected specimen measured 4.3 cm × 2.8 cm × 1.5 cm. The histologic findings were diagnostic of esophageal MALT lymphoma. Infiltration of neoplastic cells in the lateral margins of the resected specimen was not observed. However, vertical margins showed an R1 situation and mild damage to the muscularis propria. After 3 months, her dysphagia disappeared. Additional radiation therapy was then administered. After 5 months, the patient was still under surveillance and free of recurrent disease. Resection with ESD of such a large mass of MALT in the esophageal region has rarely been reported before in the literature.

Primary esophageal non-Hodgkin's lymphoma: demographics, clinical characteristics, histopathologic types, and survival in 179 patients from the SEER program and systematic review of the literature

BACKGROUND

The most frequent site for the extranodal appearance of primary non-Hodgkin's lymphomas (NHL) is the gastrointestinal (G.I.) tract. However, primary esophageal lymphoma is extremely rare. The purpose of the present study was to describe and analyze the demographics, clinical characteristics, histopathologic types, and long-term survival of patients with primary esophageal NHL registered in the surveillance, epidemiology, and end results (SEER) database.

METHODS

Retrospective cohort study. Individuals with primary esophageal lymphoma (PEL) were identified using the international classification of disease for oncology, third edition histology codes. Patients were excluded if there was no microscopic confirmation of the neoplasm or if the diagnosis was made by autopsy or death certificate. Data on demographics, clinical characteristics, histopathology and survival were analyzed using the Kaplan-Meier method, life table, and cox proportional hazard models.

RESULTS

179 patients were included (68% males, median age 66 years [IQR 46-79]). The overall survival at 1, 5 and 10 years was 65% (95% CI 57.9-72.3%), 49% (95% CI 42.1-57.3%), and 31% (95% CI 24.5-38.6%), respectively. On univariate analyses, individuals with extranodal marginal zone lymphoma (MZL) had a significantly higher overall survival when compared to patients with diffuse large B cell lymphoma (HR 0.29; 95% CI 0.11-0.73. p = 0.008). Furthermore, patients whose cancer was diagnosed after 1997 showed an improved overall survival (HR 0.40; 95% CI 0.26-0.61. p < 0.001) when compared to those diagnosed before 1997.

CONCLUSIONS

In this large population-based series, diagnosis after 1997 (year of rituximab approval by the FDA) and MZL subtype were associated with improved survival outcomes in patients with PEL.

Oncologic causes of oculopalatal tremors: neurophysiology and treatment

Oculopalatal tremor (OPT) is an acquired pathology characterized by continuous and rhythmical soft palatal movements combined with pendular nystagmus. Aside from vascular lesions, oncological masses affecting the dentatorubro-olivary pathway can impair brainstem and/or cerebellar pathways, manifesting as dyssynchronous movement. In this review, we delve into the neurophysiology of OPT along with oncological causes and treatment options based on the most recent clinical trial data. This literature review includes medication treatment data from clinical trials enrolling individuals with features of OPT, including acquired pendular nystagmus (APN). Trials were deemed eligible for inclusion in this review if one or more participants had symptoms determined by the trial authors to be caused by OPT. Trials investigating the treatment of APN secondary to a separate cause, such as multiple sclerosis, were excluded from this review. Several early treatments failed to demonstrate a benefit for patients with APN due to OPT. Trials of anticholinergic agents were largely ineffective and poorly tolerated. Botulinum toxin A demonstrated improvement in APN symptoms. Most recently, trials including memantine and gabapentin have demonstrated success with attenuation of APN. Surgical modalities such as DBS have yet to show improvement, though with only a single case report as evidence. Oculopalatal tremor is a unique manifestation of posterior fossa tumors disrupting the Guillain-Mollaret triangle. Symptom control through medication management has had limited success attributed to poor response and medication intolerance. Surgical modalities like DBS may have an emerging role in OPT treatment by targeting dyssynchronous activity in the dentatorubro-olivary pathway.

Multicentric Study of Clinicopathological Features of Primary Gastrointestinal Lymphoma of Iran: from 2011 - 2016

Background: Gastrointestinal (GI) tract is the most common site for extranodal lymphoma. The primary GI lymphoma pattern in Iran is different from western countries and has been changed during the past 40 years. Objectives: This study was done to determine the clinical and pathological characteristics of primary GI lymphoma in Tehran, Hamedan, and Mashhad regions in Iran. Methods: In this cross-sectional comparative-descriptive study, 200 patients with primary GI lymphoma in Tehran, Hamadan, and Mashhad regions from 2011 to 2016 were enrolled in a consecutive manner, where the clinical and pathological characteristics of cases were determined. Results: Among 200 patients, 141 (70.5%) subjects were male and 59 (29.5%) subjects were female. The mean age at diagnosis was 54.3 ± 19.3 years. Also, 84%, 8.5%, and 7.5% of the patients’ specimens were from Tehran, Hamedan, and Mashhad, respectively. The stomach was the principal involved location in approximately half of the cases. Diffuse large B-cell lymphoma (DLBCL), was the main subtype that was observed in 64% of the cases. Treatment in 72% of cases was a combination of surgery and chemotherapy. The 5-year survival was assessed in 147 patients with a rate of 68%. Conclusions: Primary GI lymphoma is seen more in male subjects younger than 60 years of age with non-specific symptoms. Also, DLBCL and MALToma are the main histologic types, and the 5-year survival for all cases is 68.0%. The clinical symptoms showed no specific pattern and accordingly, patients with weight loss and abdominal pain should be considered in in differential diagnosis of malignant lymphoma.

Human Gut Microbiota-associated Gastrointestinal Malignancies: A Comprehensive Review

The human gastrointestinal tract houses trillions of microbes. The gut and various types of microorganisms, including bacteria, viruses, fungi, and archaea, form a complex ecosystem known as the gut microbiota, and the whole genome of the gut microbiota is referred to as the gut microbiome. The gut microbiota is essential for homeostasis and the overall well-being of a person and is increasingly considered an adjunct "virtual organ," with a complexity level comparable to that of the other organ systems. The gut microbiota plays an essential role in nutrition, local mucosal homeostasis, inflammation, and the mucosal immune system. An imbalanced state of the gut microbiota, known as dysbiosis, can predispose to development of various gastrointestinal malignancies through three speculated pathogenic mechanisms: (a) direct cytotoxic effects with damage to the host DNA, (b) disproportionate proinflammatory signaling inducing inflammation, and (c) activation of tumorigenic pathways or suppression of tumor-suppressing pathways. Several microorganisms, including Helicobacter pylori, Epstein-Barr virus, human papillomavirus, Mycoplasma species, Escherichia coli, and Streptococcus bovis, are associated with gastrointestinal malignancies such as esophageal adenocarcinoma, gastric adenocarcinoma, gastric mucosa-associated lymphoid tissue lymphoma, colorectal adenocarcinoma, and anal squamous cell carcinoma. Imaging plays a pivotal role in diagnosis and management of microbiota-associated gastrointestinal malignancies. Appropriate use of probiotics, fecal microbiota transplantation, and overall promotion of the healthy gut are ongoing areas of research for prevention and treatment of malignancies. Online supplemental material is available for this article. ^©RSNA, 2021.

Pediatric Stomach and Duodenal Imaging

Pediatric stomach and duodenum abnormalities constitute a unique spectrum of conditions unlike adults which are categorized broadly into congenital, inflammatory, neoplastic and miscellaneous conditions. The aim of this article is to describe the role of imaging modalities in gastric and duodenal pathology in children. Some of the entities are unique to this age group and their imaging findings are also highlighted.

Mesenchymal Tumors and Lymphoproliferative Diseases of the Stomach and Duodenum

Neoplasms of the stomach are classified into two large categories on the basis of the cell of origin: epithelial and nonepithelia. The vast majority of both benign and malignant tumors of the stomach are of epithelial origin, with mesenchymal and neuroendocrine tumors being much less common. The epithelial tumors arise from the mucosa while the nonepithelial tumors arise from the submucosa, muscularis propria, or serosa. The nonepithelial or intramural tumors of stomach include gastrointestinal stromal tumors, leiomyomas, schwannoma, granular cell tumors, glomus tumor, leiomyosarcoma, Kaposi sarcoma, lymphoma, and others. In this review, radiological appearance of mesenchymal tumors and lymphoproliferative tumors are described.

Ileo-Colonic Fistula Due to Diffuse Large B Cell Lymphoma: Unusual Presentation of a Rare Disease

Malignant ileocolonic fistulas have seldom been documented as complications of a primary gastrointestinal lymphoma (PGIL) such as aggressive diffuse large B cell lymphoma (DLBCL). These fistulas are frequently misdiagnosed due to the nonspecific clinical presentation. Currently, there is no standardized treatment approach, although a couple have been suggested with varying outcomes. We describe a case of DLBCL complicated with a malignant ileocolonic fistula in a 55-year-old male with a favorable outcome after surgery and chemotherapy.

Lymphoma presenting as small bowel obstruction: A case report

Small bowel lymphoma accounts for 10%-30% of gastro-intestinal tumors. Clinical presentation is not specific. CT scans helps the diagnosis showing some characteristic appearances such as wall thickening of the loops, enlarged lymph nodes and infiltration of mesenteric fat. Pseudoaneurysmal intestinal dilatation is uncommon and may cause bowel obstruction which is a diagnostic and therapeutic emergency. We report the case of a 73-year-old man, who presented for occlusive syndrome revealing hail lymphoma. Pseudoaneurysmal intestinal dilatation is an uncommon presentation of lymphoma that should evoke the diagnosis especially when associated to wall thickening of the loops and lymphadenopathy.

Imaging Findings of a Malignant Rhabdoid Tumor in the Stomach: A Case Report

악성 횡문근양 종양은 주로 영유아의 신장에서 발생하는 공격적인 종양이다. 신장 이외의 조직에서 발생한 경우 신외성 악성 횡문근양 종양이라 하고 중추신경계, 간, 뇌, 피부, 연조직 등에서 드물게 보고되었다. 위에서 발생한 악성 횡문근양 종양은 매우 드물다. 저자들은 흑색변을 주소로 내원한 72세 남자의 위에서 발견된 악성 신외성 횡문근양 종양이 림프종과 유사한 영상 소견을 보인 예를 경험하여 보고한다.

Ileo-colonic lymphoma: presentation, diagnosis, and management

PURPOSE OF REVIEW

The gut-associated lymphoid tissue (GALT), the bulk of which is located in the ileo-colonic region comprises the lymphoid cells of the gastrointestinal tract and confers specific immunological responses. Repetitive antigenic stimulation of these cells predispose to a monoclonal proliferation of this tissue and the eventual development of lymphoma. The gastrointestinal tract is the most commonly involved site of extranodal lymphomas. This review will focus primarily on lymphomas of the ileo-colonic region (defined as the terminal ileum, the colon, and the rectum). We will discuss the epidemiology, pathogenesis, and presentation as well as current practices in diagnosis and management.

RECENT FINDINGS

Despite the majority of the GALT to be located in the ileo-colonic region of the gut, the lymphomas in this location are relatively rare. However, the overall annual incidence of ileo-colonic lymphomas is steadily increasing. This entity has a varied spectrum of clinical presentations. Ileo-colonoscopy with adequate targeted biopsies can serve as a gold standard for definitive diagnosis. Ileo-colonic lymphomas may be managed with chemotherapy alone while surgery is reserved for highly aggressive tumors or clinical emergencies. Radiation is not a preferred adjuvant treatment for lymphomas in this location of the gut. Adequate endoscopic surveillance measures and tools to potentially prevent recurrence and improve the overall prognosis of this disease are lacking.

SUMMARY

Ileo-colonic lymphomas are rare and can present with varied symptoms and signs. Endoscopy with adequate sampling can aid in making a definitive diagnosis. Chemotherapy can be highly effective in management while surgery is indicated for emergency presentations. Adequate endoscopic surveillance tools are lacking, yet imperative to prevent recurrence and improve prognosis.

Aneurysmal dilatation of colon: A rare imaging presentation of colon cancer

Aneurysmal dilatation of colon is a rare imaging feature of colon adenocarcinoma. Two cases with massive aneurysmal dilatation of the colon secondary to moderately differentiated adenocarcinomas are described. The 2 cases presented with asymmetric and progressive abdominal distension with no obstructive symptoms. Contrast-enhanced computed tomography of the abdomen and pelvis demonstrated marked aneurysmal dilatation of the involved segments of the colon and circumferential mural thickening. Colonoscopy found markedly dilated lumen in the involved segment of the colon. Histology of the biopsy specimens taken during colonoscopy revealed moderately differentiated adenocarcinoma with extensive infiltration of colon wall and damage of myenteric nerve plexus.

The pediatric stomach - masses and mass-like pathology

Diagnostic imaging of pediatric gastric masses often provides a challenge for the practicing radiologist. Radiologists should be aware of this relatively unusual pathology, particularly in cross-sectional imaging findings. We will review pediatric gastric masses and mass-like lesions, focusing on neoplastic and inflammatory etiologies.

Exploring the neglected segment of the intestine: the duodenum and its pathologies

Herein we reviewed the computed tomography (CT) findings of a spectrum of pathological entities affecting the duodenum. We discuss the CT findings of some congenital, inflammatory, traumatic, and neoplastic pathologies of the duodenum along with the conventional barium studies of selected conditions. Pathologies of this C-shaped intestinal segment, derived from both foregut and midgut, are often overlooked in clinical practice and radiological literature. While congenital anomalies like duplication cysts and diverticula are usually asymptomatic, annular pancreas and malrotation may manifest in the first decade of life. Primary as well as secondary involvement of the duodenum by various disease processes can be evaluated by careful CT technique and proper attention to the duodenum. Among congenital conditions, annular pancreas, duplication cyst, superior mesenteric artery syndrome, midgut volvulus, and diverticula are presented. Duodenal involvement in adenocarcinoma, lymphoma, gastrointestinal stromal tumours, Crohn’s disease, and groove pancreatitis are discussed. Duodenal wall haematoma and traumatic duodenal perforation causing pneumoretroperitoneum in two patients after blunt trauma of the abdomen are also illustrated. CT provides superb anatomic detail and offers high diagnostic specificity for the detection of duodenal pathologies because it allows direct imaging of the intestinal wall, secondary signs of bowel disease within the surrounding mesentery, and abnormal findings in adjacent structures. Primary duodenal malignancies and local extension from adjacent malignancies can be diagnosed by CT reliably. CT also plays a vital role in the diagnosis of traumatic duodenal injury by differentiating between mural haematoma and a duodenal perforation because the latter requires immediate surgical intervention.

Beyond adenocarcinoma: MRI of uncommon rectal neoplasms and mimickers

OBJECTIVE

To provide a review of rare rectal tumors beyond adenocarcinoma.

RESULTS

Rectal cancer is a common malignancy, both in the United States and abroad. In addition to adenocarcinoma, abdominal radiologists will encounter a variety of other less common rectal masses, both benign and malignant neoplasms as well as non-neoplastic mimickers. Familiarity with these conditions and their characteristic features on MRI is useful in clinical practice. In this article, a number of such conditions are discussed, with an emphasis on distinguishing features on MRI of the rectum.

CONCLUSION

Familiarity with the MRI features of rare rectal tumors beyond adenocarcinoma, as well as a small number of non-neoplastic mimics, is important for abdominal imagers to make diagnostic differentials and to assist in treatment planning.

Primary colorectal lymphoma: computed tomography and double-contrast barium enema examination findings with histopathological correlation in 19 patients

Background

Primary colorectal lymphoma (PCL) is a rare disorder, the accurate imaging diagnosis of which remains a clinical challenge. This study aimed to characterize the imaging features of PCL by double-contrast barium enema (DCBE) examination and computed tomography (CT) and correlate them with histopathological findings.

Methods

DCBE (n=6) and CT (n=19) findings for 19 pathologically proven PCLs were evaluated and compared with histopathological findings in this retrospective analysis.

Results

Non-Hodgkin lymphoma was present in all patients, and the most common histological type was diffuse large B-cell lymphoma (63.2%, 12/19). The most common site was the ileocecum (84.2%, 16/19). CT revealed circumferential infiltrative lesions (68.4%, 13/19), polypoid masses (26.3%, 5/19) and ulcerative lesions (5.3%, 1/19). Most (94.7%, 18/19) lesions appeared as moderate enhancements. Fourteen (73.7%, 14/19) patients had serous membrane infiltration presenting as a poorly defined serous membrane and focal opacities in the pericolonic fat. Regional lymph node involvement was observed in twelve (63.2%, 12/19) patients who presented with aggregated nodules or masses. Frequent findings of the DCBE exam included a filling defect and niche with slight mucosal destruction, mild luminal narrowing and preserved peristalsis. The imaging appearance reflected the gross pathological findings well, although the preoperative diagnostic accuracy was low.

Conclusions

The imaging features of PCL have a relatively characteristic appearance but are still, at times, hardly differentiated from carcinoma. Familiarity with the radiological features of PCL on DCBE and CT can help ensure a correct diagnosis.

Primary lymphomas of the intraabdominal solid organs and the gastrointestinal tract: spectrum of imaging findings with histopathological confirmation

Unlike nodal lymphoma, primary lymphomas of the intraabdominal organs are uncommon neoplasms whose diagnosis may be challenging in certain clinical circumstances. Despite this difficulty for imaging diagnosis, there are several imaging features on ultrasonography, computed tomography, magnetic resonance imaging, and positron emission tomography that may suggest the correct diagnosis. The scope of this review is to describe and illustrate the imaging features of primary lymphoma of intraabdominal organs providing clues to the diagnosis, together with their pathological correlations.

[Extranodal abdominal lymphomas]

BACKGROUND

Extranodal manifestations occur in up to 40% of non-Hodgkin lymphomas. The prevalence of extranodal involvement has increased.

OBJECTIVES

A comprehensive overview on lymphoma involvement in the parenchymatous abdominal organs, the gastrointestinal tract, and the peritoneal cavity under due consideration of clinical implications is given.

MATERIALS AND METHODS

A selective literature search with analysis of dedicated original research articles and reviews was carried out. Clinical guidelines are discussed.

RESULTS

Extranodal abdominal lymphoma involvement usually occurs secondarily in advanced disease. Sites involved most frequently are the liver and the gastrointestinal tract. Extranodal abdominal lymphoma involvement is more common in the immunocompromised patient.

CONCLUSION

Imaging findings of extranodal abdominal lymphoma are variable. Lymphoma is an important differential diagnosis to be considered in unclear tumor diseases.

Comparison of the Diagnostic Ability of Endoscopic Ultrasonography and Abdominopelvic Computed Tomography in the Diagnosis of Gastric Subepithelial Tumors

Background/Aims

Endoscopic ultrasonography (EUS) is the most efficient imaging modality for gastric subepithelial tumors (SETs). However, abdominopelvic computed tomography (APCT) has other advantages in evaluating the characteristics, local extension, or invasion of SETs to adjacent organs. This study aimed to compare the diagnostic ability of EUS and APCT based on surgical histopathology results.

Methods

We retrospectively reviewed data from 53 patients who underwent both EUS and APCT before laparoscopic wedge resection for gastric SETs from January 2010 to December 2017 at a single institution. On the basis of histopathology results, we assessed the diagnostic ability of the 2 tests.

Results

The overall accuracy of EUS and APCT was 64.2% and 50.9%, respectively. In particular, the accuracy of EUS vs. APCT for the diagnosis of gastrointestinal stromal tumors (GISTs), leiomyomas, and ectopic pancreas was 83.9% vs. 74.2%, 37.5% vs. 0.0%, and 57.1% vs. 14.3%, respectively. Most of the incorrect diagnoses with EUS involved hypoechoic lesions originating in the fourth echolayer, with the most common misdiagnosed lesions being GISTs mistaken for leiomyomas and vice versa.

Conclusions

APCT showed a lower overall accuracy than EUS; however, APCT remains a useful modality for malignant/potentially malignant gastric SETs.

Primary Diffuse Large B-Cell Lymphoma of the Descending Colon

Primary non-Hodgkin lymphoma of the gastrointestinal tract is rare with an incidence of 10-15% of all non-Hodgkin lymphoma cases and 1-4% of all gastrointestinal tumors. The most common sites of involvement include the stomach, small intestines, colon and rectum. Primary colorectal lymphoma is extremely rare representing only 0.2-0.6% of all colorectal malignancies. The presentation is usually non-specific leading to delay in diagnosis. Imaging is used to locate the tumor and its extension. Colonoscopy usually shows a fungating mass, infiltrative or ulcerative lesion. Diffuse large B-cell lymphoma is the most common histological subtype. Management of diffuse large B-cell lymphoma usually involves chemotherapy, radiation, surgery or a combination approach.