Cross-sectional imaging of extranodal involvement in abdominopelvic lymphoproliferative malignancies

A rare case of Burkitt's lymphoma of the duodenal bulb in a 9 year-old child - A case report and review of the literature

INTRODUCTION AND IMPORTANCE

The presence of Burkitt's lymphoma in the duodenum is very rare, as this lymphoma is most commonly found at the end of the ileum, as it contains a high proportion of lymphoid tissue, spreads rapidly, and is aggressive. Primary diagnosis by histological examination. It gives a starry sky view with positive for tumor markers.

CASE PRESENTATION

We reported a child suffering from recurrent vomiting with weight loss, and a radiological examination revealed the presence of a mass in the duodenum causing obstruction there. Upper gastrointestinal endoscopy was performed, and biopsies were obtained for histologic examination. Burkitt's lymphoma was then diagnosed, palliative surgery was performed, and appropriate chemotherapy was subsequently applied.

CLINICAL DISCUSSION

Burkitt's lymphoma is rare in the duodenum. However, it should be considered in the differential diagnosis of duodenal problems to allow early diagnosis and treatment.

CONCLUSION

Burkitt's lymphoma is diagnosed by histologic examination and is very aggressive. However, it is highly responsive to chemotherapy in the absence of poor prognostic factors.

Adrenal Neoplasms: Lessons from Adrenal Multidisciplinary Tumor Boards

The radiologic diagnosis of adrenal disease can be challenging in settings of atypical presentations, mimics of benign and malignant adrenal masses, and rare adrenal anomalies. Misdiagnosis may lead to suboptimal management and adverse outcomes. Adrenal adenoma is the most common benign adrenal tumor that arises from the cortex, whereas adrenocortical carcinoma (ACC) is a rare malignant tumor of the cortex. Adrenal cyst and myelolipoma are other benign adrenal lesions and are characterized by their fluid and fat content, respectively. Pheochromocytoma is a rare neuroendocrine tumor of the adrenal medulla. Metastases to the adrenal glands are the most common malignant adrenal tumors. While many of these masses have classic imaging appearances, considerable overlap exists between benign and malignant lesions and can pose a diagnostic challenge. Atypical adrenal adenomas include those that are lipid poor; contain macroscopic fat, hemorrhage, and/or iron; are heterogeneous and/or large; and demonstrate growth. Heterogeneous adrenal adenomas may mimic ACC, metastasis, or pheochromocytoma, particularly when they are 4 cm or larger, whereas smaller versions of ACC, metastasis, and pheochromocytoma and those with washout greater than 60% may mimic adenoma. Because of its nonenhanced CT attenuation of less than or equal to 10 HU, a lipid-rich adrenal adenoma may be mimicked by a benign adrenal cyst, or it may be mimicked by a tumor with central cystic and/or necrotic change such as ACC, pheochromocytoma, or metastasis. Rare adrenal tumors such as hemangioma, ganglioneuroma, and oncocytoma also may mimic adrenal adenoma, ACC, metastasis, and pheochromocytoma. The authors describe cases of adrenal neoplasms that they have encountered in clinical practice and presented to adrenal multidisciplinary tumor boards. Key lessons to aid in diagnosis and further guide appropriate management are provided. © RSNA, 2023 Online supplemental material is available for this article. Quiz questions for this article are available through the Online Learning Center.

A case report of a collision tumor composed of pancreatic ductal adenocarcinoma and peri-pancreatic mucosa-associated lymphoid tissue lymphoma

BACKGROUND

Collision tumors are composed of two distinct tumor components. Collision tumors composed of pancreatic ductal adenocarcinoma and malignant lymphoma occurring in the pancreas have not been previously described in the scientific literature. In this case report, we describe a unique patient with a collision tumor composed of pancreatic ductal adenocarcinoma and peri-pancreatic mucosa-associated lymphoid tissue (MALT) lymphoma occurring in the pancreas.

CASE PRESENTATION

An 82-year-old woman presented to our hospital complaining of dizziness. Computed tomography (CT) and magnetic resonance imaging (MRI) showed a large lymphoid lesion spreading from the peri-pancreatic tissue heading to the hepatic hilar plate, involving the hepatoduodenal ligament and the entire duodenum, also showing a hard tumor in the pancreas head. We performed echo-guided needle biopsies for each tumor and diagnosed a collision tumor composed of pancreatic ductal adenocarcinoma and low-grade B cell lymphoma. The patient underwent pancreaticoduodenectomy. The resected specimen showed an elastic hard tumor, 90 × 75 mm in size, located in the pancreatic head, and a whitish-yellow hard tumor involving the lower bile duct, 31 mm in size, located in the center of the pancreatic head. Pathological and immunohistochemical examination proved that pancreatic ductal adenocarcinoma and MALT lymphoma originating from the peri-pancreatic head collided in the pancreatic head.

CONCLUSIONS

To best of our knowledge, this is the first report of a surgically resected collision tumor of pancreatic ductal adenocarcinoma and MALT lymphoma originating from the peri-pancreatic head. A needle biopsy is useful when inconsistent findings are observed on diagnostic CT and MRI of tumor lesions since there is the possibility of a collision tumor.

Multiple hepatic and osseous focal lesions without splenomegaly and/or lymph nodes enlargement

Background

Hepatic involvement is a common extranodal manifestation of common and some rare hematologic malignancies. Although the imaging features of more common hepatic diseases such as hepatocellular carcinoma, metastases, and infection may overlap with those of hepatic hematologic malignancies, combining the imaging features with clinical manifestations and laboratory findings can facilitate correct diagnosis. Imaging has an important role in the diagnosis of hepatic focal lesions.

Case presentation

A case presented with isolated multiple hepatic focal lesions without nodal or spleen enlargement diagnosed only by immunohistochemical study and turned out to be primary hepatic lymphoma (PHL). PHL is rare with roughly 100 described cases and accounts for less than 1% of all non-Hodgkin lymphomas. Osseous involvement adds more challenge to the diagnosis.

Conclusion

Hepatologists must be aware of PHL as it may be confused with more common hepatic diseases, mainly multifocal HCC and/or hepatic metastasis.

Two-Stage Deep Learning Model for Automated Segmentation and Classification of Splenomegaly

Splenomegaly is a common cross-sectional imaging finding with a variety of differential diagnoses. This study aimed to evaluate whether a deep learning model could automatically segment the spleen and identify the cause of splenomegaly in patients with cirrhotic portal hypertension versus patients with lymphoma disease. This retrospective study included 149 patients with splenomegaly on computed tomography (CT) images (77 patients with cirrhotic portal hypertension, 72 patients with lymphoma) who underwent a CT scan between October 2020 and July 2021. The dataset was divided into a training (n = 99), a validation (n = 25) and a test cohort (n = 25). In the first stage, the spleen was automatically segmented using a modified U-Net architecture. In the second stage, the CT images were classified into two groups using a 3D DenseNet to discriminate between the causes of splenomegaly, first using the whole abdominal CT, and second using only the spleen segmentation mask. The classification performances were evaluated using the area under the receiver operating characteristic curve (AUC), accuracy (ACC), sensitivity (SEN), and specificity (SPE). Occlusion sensitivity maps were applied to the whole abdominal CT images, to illustrate which regions were important for the prediction. When trained on the whole abdominal CT volume, the DenseNet was able to differentiate between the lymphoma and liver cirrhosis in the test cohort with an AUC of 0.88 and an ACC of 0.88. When the model was trained on the spleen segmentation mask, the performance decreased (AUC = 0.81, ACC = 0.76). Our model was able to accurately segment splenomegaly and recognize the underlying cause. Training on whole abdomen scans outperformed training using the segmentation mask. Nonetheless, considering the performance, a broader and more general application to differentiate other causes for splenomegaly is also conceivable.

Adrenal Lesions: A Review of Imaging

Adrenal lesions are frequently incidentally diagnosed during investigations for other clinical conditions. Despite being usually benign, nonfunctioning, and silent, they can occasionally cause discomfort or be responsible for various clinical conditions due to hormonal dysregulation; therefore, their characterization is of paramount importance for establishing the best therapeutic strategy. Imaging techniques such as ultrasound, computed tomography, magnetic resonance, and PET-TC, providing anatomical and functional information, play a central role in the diagnostic workup, allowing clinicians and surgeons to choose the optimal lesion management. This review aims at providing an overview of the most encountered adrenal lesions, both benign and malignant, including describing their imaging characteristics.

FDG-PET/CT Variants and Pitfalls in Haematological Malignancies

Hematologic malignancies represent a vast group of hematopoietic and lymphoid cancers that typically involve the blood, the bone marrow, and the lymphatic organs. Due to extensive research and well defined and standardized response criteria, the role of [¹⁸F]FDG-PET/CT is well defined in these malignancies. Never the less, the reliability of visual and quantitative interpretation of PET/CT may be impaired by several factors including inconsistent scanning protocols and image reconstruction methods. Furthermore, the uptake of [¹⁸F]FDG not only reflects tissue glucose consumption by malignant lesions, but also in other situations such as in inflammatory lesions, local and systemic infections, benign tumors, reactive thymic hyperplasia, histiocytic infiltration, among others; or following granulocyte colony stimulating factors therapy, radiation therapy, chemotherapy or surgical interventions, all of which are a potential source of false-positive or negative interpretations. Therefore it is of paramount importance for the Nuclear Medicine Physician to be familiar with, not only the normal distribution of [¹⁸F]FDG in the body, but also with the most frequent findings that may hamper a correct interpretation of the scan, which could ultimately alter the patients management. In this review, we describe these myriad of situations so the interpreting physician can be familiar with them, providing tools for their correct identification and interpretation when possible.

Incidental Splenic Findings on Cross-Sectional Imaging

Incidental splenic focal findings are commonly encountered in clinical practice and frequently represent a diagnostic dilemma due to nonspecific imaging features. Most are benign, particularly in patients without a history of malignancy and without symptoms of fever, weight loss, or left upper quadrant or epigastric pain. Incidental malignant splenic processes are exceedingly rare. This article reviews imaging characteristics of incidental focal splenic findings, and proposes a practical approach for management of such findings, which can prevent unnecessary workup and its related drawbacks in clinical practice.

Granuloma With an Underlying Lymphoma: A Diagnostic Challenge and a Wider Histologic Spectrum Including Adult T-Cell Leukemia/Lymphoma

Granulomatous reaction is not uncommon in histopathology, with various etiologies in different organs and geographic regions. Lymphoma is one of the underlying causes of granuloma; and sometimes the neoplastic cells may be masked by the granulomatous reaction. In this report, we present our experience with 7 lymphoma cases of various histologic types with coexisting granuloma to show the diagnostic challenges. In all cases, a granulomatous reaction was simultaneously present with the neoplastic cells. The 7 cases included 3 cases of adult T-cell leukemia/lymphoma in the lymph node or skin including one coexisting with mycobacterial infection, 2 cases of classical Hodgkin lymphoma involving the liver, and 1 case each of systemic Epstein-Barr virus-positive peripheral T-cell lymphoma and a hepatic inflammatory pseudotumor-like follicular dendritic cell sarcoma. Three cases were initially misdiagnosed as reactive change or mycobacterial infection instead of lymphoma, and a wrong histologic lymphoma type was diagnosed in 1 case. In this report, we showed that granulomatous reaction might mask lymphomas of various histologic types; and a diagnosis of mycobacterial infection or sarcoidosis could not exclude the possibility of an underlying lymphoma. We emphasized the importance of detailed histologic examination with the aid of ancillary studies to reach a correct diagnosis and to avoid inappropriate management of the patients. Our study also broadened the spectrum of lymphoma types coexisting with granuloma.

Pitfalls and differential diagnosis on adrenal lesions: current concepts in CT/MR imaging: a narrative review

The purpose of this pictorial essay is to review the imaging findings of adrenal lesions. Adrenal lesions could be divided into functioning or non-functioning masses, primary or metastatic, and benign or malignant. Imaging techniques have undergone significant advances in recent years. The most significant objective of adrenal imaging is represented by the detection and, when possible, characterization of adrenal lesions in order to direct patient management correctly. The detection and management of adrenal lesions is based on cross-sectional imaging obtained with non-contrast CT (tumour density), contrast-enhanced CT including delayed washout (either absolute percentage washout or relative percentage one) and finally with MR chemical shift analysis (loss of signal intensity between in-phase and out-of-phase images including both qualitative and quantitative estimates of signal loss). The small incidental adrenal nodules are benign, in most of cases; some tumors such as lipid-rich adenoma and myelolipoma have characteristic features that can be diagnosed accurately in CT. On contrary, if the presenting contrast-enhanced CT shows an adrenal mass with uncertain or malignant morphologic features, particularly in patients with a known history of malignancy, further evaluations should be considered. The most significative implications for radiologists are represented by how to assess risk of malignancy on imaging and what follow-up to indicate if an adrenal incidentaloma is not surgically removed.

Primary hepatic diffuse large B-cell lymphoma presenting unusual imaging features

Primary hepatic lymphomas are frequently misdiagnosed, due to their rarity and non-specific clinical manifestations. As these tumors can be successfully treated with chemotherapy and/or radiotherapy, early recognition on imaging is essential to avoid unnecessary surgery. We report a case of primary hepatic lymphoma in a 73-year-old woman presenting with a 1-week history of persistent fever and elevated hepatobiliary enzymes. Ultrasound showed a hypoechoic hepatic mass in the anterior segment. Dynamic contrast-enhanced computed tomography (CT) revealed an ill-defined solitary mass showing peripherally dominant slight-to-moderate enhancement contrasting with a hypovascular central area. On magnetic resonance imaging, the mass showed moderate hyperintensity on T2-weighted imaging, hypointensity on T1-weighted imaging, doughnut-like hyperintensity on diffusion-weighted imaging, and an obviously low apparent diffusion coefficient (ADC). The pattern of enhancement resembled that of CT. Neither calcification nor any fat component was observed. Doughnut-like accumulation was seen on ¹⁸F-fluorodeoxyglucose (FDG)-positron emission tomography/CT without other FDG-avid lesions. Imaging findings suggested the possibility of cholangiocellular carcinoma, but the low ADC and extremely high FDG accumulation were suggestive of malignant lymphoma, and diffuse large B-cell lymphoma was pathologically confirmed from percutaneous biopsy. The mass disappeared after radiochemotherapy, and no recurrence has been observed for 3 years.

Correlative analysis of overall survival with clinical characteristics in 127 patients with mantle cell lymphoma: a multi-institutional cohort in Taiwan

Mantle cell lymphoma (MCL) is a B-cell non-Hodgkin lymphoma often with extranodal involvement at diagnosis, and yet how this feature correlates with survival awaits elucidation. To address this issue, a correlative analysis between clinical features of 127 MCL patients and their overall survival (OS) was conducted. In this cohort, the median age at MCL diagnosis was 62 years and 81% were males. Eighty-four percent of patients were Ann Arbor stage 4, and 15% were blastoid variants. In patients with gastrointestinal MCL, approximately 40% had gastric involvement. In treatment, CHOP-based induction chemotherapy was given to 61.1% of patients. One-third of patients undertook autologous stem cell transplant (SCT), and 4.7% had allogeneic SCT. The median OS was 82 months and well-stratified in MIPI risk groups. In the multivariate analysis for OS, blastoid variants and gastric involvement were both independent risk factors whereas auto-SCT had a protective effect. Overall, this study corroborated with the current understandings and international therapeutic standards for MCL. Auto-SCT associated with a better OS while allo-SCT remained an option for blastoid variants and those who failed Auto-SCT. Interestingly, patients with gastric involvement tended to have worse survival, a finding that spawns more studies to investigate the mechanism.

Diagnostic approach in hepatic lymphoma: radiological imaging findings and literature review

PURPOSE

Imaging manifestations of hepatic lymphoma, both primary (PHL) and secondary (SHL), are extremely variable and non-specific, but some features are useful diagnostic clues in an appropriate clinical setting. Through a PubMed search, we found several published reviews focused on PHL and SHL diagnosis. However, to the best of our knowledge, few of them encompass a comprehensive analysis of all the diagnostic tools and relative radiological findings. The aim of this review is to provide a description of the radiological features of both PHL and SHL, by critically analyzing the available literature.

MATERIALS AND METHODS

An extensive review of published literature along with a description of personal case series of both PHL and SHL has been conducted.

RESULTS

SHL can be easily diagnosed with imaging techniques, as it is usually associated with node disease. On the contrary the diagnosis can be a challenge in PHL, often mimicking HCC or liver metastasis of adenocarcinoma. In this context, multiparametric MRI plays a fundamental role in the differential diagnosis. Both for PHL and SHL, liver involvement presents as solitary or multiple lesions or as diffuse infiltrative disease.

CONCLUSION

PHL and SHL may be correctly characterized using different radiological techniques. Both CT and MRI have showed a good correlation with histology, as they permit to distinguish between lymphomatous tissue, and necrotic and fibrotic areas.

LI-RADS to categorize liver nodules in patients at risk of HCC: tool or a gadget in daily practice?

PURPOSE

To determine the effectiveness of liver reporting and data system (LI-RADS) to diagnose hepatocellular carcinoma (HCC) and to retrospectively evaluate its impact on the adopted therapeutic strategy.

MATERIALS AND METHODS

Preoperative imaging of 40 of 350 patients (median age 66, 31 M/9 F) submitted to liver resection for suspected HCC, between January 2008 and August 2019, has been retrospectively analyzed by two radiologists with different expertise, according to CT/MRI LI-RADS^® v2018, both blinded to clinical and pathological results and untrained to using aforementioned scoring system.

RESULTS

The perfect agreement between the readers was about 62.5% (25/40) (Cohen k: 0.41), better for LR-5 category (16/25) and higher in magnetic resonance imaging (MRI) investigations (68%; 13/19), which has been demonstrated the modality of choice for diagnosis of high probable and certain HCC, with arterial phase hyperenhancement as the most sensitive and accurate major feature. Compared to final histology, LR4 and LR5 scores assigned by senior radiologist reached sensitivity, specificity, positive and negative predictive values (PPV, PNV) and diagnostic accuracy of 90,9%, 29,0%, 93,8%, 62,5% and 87,5%, respectively, slightly higher than junior's ones. Misdiagnosis of HCC was done by both radiologists in the same two patients: 1 primary hepatic lymphoma (PHL) and 1 regenerative liver nodule (RLN). If LI-RADS would have been applied at the time of pre-surgical imaging, treatment planning would be modified in 10% of patients (4/40); the patient scheduled as LR-3 and finally resulted a focal nodular hyperplasia would have avoided liver resection.

CONCLUSIONS

Application of LI-RADS, especially on MRI, may provide a more accurate evaluation of suspected HCC. PHL and RLN are the Achille's heels according to our experience.

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.

Imaging features of adrenal masses

The widespread use of imaging examinations has increased the detection of incidental adrenal lesions, which are mostly benign and non-functioning adenomas. The differentiation of a benign from a malignant adrenal mass can be crucial especially in oncology patients since it would greatly affect treatment and prognosis. In this setting, imaging plays a key role in the detection and characterization of adrenal lesions, with several imaging tools which can be employed by radiologists. A thorough knowledge of the imaging features of adrenal masses is essential to better characterize these lesions, avoiding a misinterpretation of imaging findings, which frequently overlap between benign and malignant conditions, thus helping clinicians and surgeons in the management of patients. The purpose of this paper is to provide an overview of the main imaging features of adrenal masses and tumor-like conditions recalling the strengths and weaknesses of imaging modalities commonly used in adrenal imaging.

A primary retroperitoneal anaplastic lymphoma kinase-positive anaplastic large cell lymphoma with tumor thrombosis

Anaplastic lymphoma kinase (ALK)-positive anaplastic large cell lymphoma (ALCL) is a T cell subtype of non-Hodgkin’s lymphoma (NHL). Typically, lymphoma rarely infiltrates vascular structure. In this article, we present a case of retroperitoneal ALK-positive ALCL with splenic venous tumor thrombosis. A 62-year-old patient presented to our institute with the symptoms of epigastric pain, abdominal distension, and reduced bowel movement. Physical examination indicated no enlarged peripheral lymph nodes or abdominal mass. Laboratory workup revealed granulocytosis, abnormal coagulation function, and normal level of lactic dehydrogenase (LDH). Contrast-enhanced computed tomography (CT) showed a retroperitoneal mass with involvement of pancreas and duodenum and formation of splenic venous tumor thrombus. Ultrasonography-guided retroperitoneal lesion biopsy confirmed the diagnosis of ALK-positive ALCL. The patient was able to tolerate oral intake after two cycles of chemotherapy and showed no sign of lymphoma by positron emission tomography (PET)-CT after the fourth cycle of chemotherapy. In spite of its rarity, lymphoma should be taken into account as a differential diagnosis of other malignancies with tumor thrombosis.

Adult multicentric burkitt lymphoma with bowel obstruction due to intussusception

Primary malignant tumors of the small intestine are very rare, accounting for 2%-3% of all gastrointestinal malignancies. Lymphoma constitutes about 15%-20% of all small intestine neoplasms and 20%-30% of all primary gastrointestinal lymphomas. The ileum is the most common site for gastrointestinal lymphomas. Because the symptoms and physical findings are non-specific, the preoperative diagnosis is usually difficult. In this case report, we describe the highly unusual case of sporadic Burkitt lymphoma with complete intestinal obstruction due to intussusception of the proximal jejunum and discuss the treatment options.

Low rate of spleen involvement in sporadic Burkitt lymphoma at staging on PET-CT

BACKGROUND

Burkitt lymphoma is a highly aggressive B cell non-Hodgkin lymphoma. Cross-sectional imaging techniques that are used to detect liver and spleen involvement by lymphoma have high rates of false negative and false positive findings, and as such may reduce the accuracy of staging.

PURPOSE

This retrospective study evaluated the use of FDG PET-CT in determining splenic involvement at staging, in a relatively large cohort of adult patients with the sporadic form of Burkitt lymphoma (SBL).

PATIENTS AND METHODS

All adult patients who underwent FDG PET-CT for staging of SBL at one medical center during 2005-2014 were enrolled for this retrospective study.

RESULTS

Data were analyzed of 20 patients, with median age 49 years; 17 were male. PET-CT revealed highly intense FDG uptake, mean SUV max 11.4 ± 7.49 (range 4.3-38) in various tissues. None of the 20 patients had either focal or diffuse increased uptake of FDG in the spleen parenchyma. In 2 patients, there were highly FDG-avid soft tissue masses adjacent to the spleen, both in the context of direct peritoneal disease extension.

CONCLUSION

The spleen is rarely involved in SBL at the time of staging, according to PET-CT, except in cases with direct extension from adjacent peritoneal mass. The low rate of spleen involvement according to PET-CT may serve as a specific characteristic of SBL. Larger-scale clinical studies incorporating PET-CT scans in SBL are needed to confirm our observation.

The use of Deauville 5-point score could reduce the risk of false-positive fluorodeoxyglucose-positron emission tomography in the posttherapy evaluation of patients with primary bone lymphomas

Primary bone lymphoma (PBL) is a rare disease. Little is reported about response evaluation procedures in these patients. Our aim was to evaluate response to therapy according to fluorodeoxyglucose-positron emission tomography (FDG-PET) results, and in particular to test the Deauville 5-point scale as compared to the visual evaluation of FDG-PET scans in PBL. In this single-center study, we diagnosed 31 consecutive patients with PBL, of which 24 were evaluated with end-of-treatment FDG-PET. Patients' ages ranged from 19 to 82 years. Six patients were treated with chemotherapy, 24 with chemotherapy and radiotherapy, and one patient with radiotherapy alone. Six patients were affected by a pathological fracture. Four patients died within the range of 3 to 36 months after diagnosis. The average follow-up of the remaining patients was 70 (24–173) months. Overall survival was 87% at 5 years. The only positive prognostic factor was complete remission after chemotherapy. According to visual criteria, end-of-treatment FDG-PET was evaluated in 24 patients and it was positive in 11 (46%) and negative in 13 patients. We organized a retrospective central-blinded revision of end-of-therapy FDG-PET scans using the 5-point Deauville Score (DS). We reviewed 17 out of 24 patients and obtained the following results: at the end of therapy, 12 patients with DS score 2, three patients with DS score 3, one patient with DS score 4, and none with DS score 5. Considering that all the 24 patients achieved complete remission after treatment, visual interpretation produced 11/24 false-positive results, and DS interpretation produced 1/17 false-positive results, thus significantly reducing the number of false positives. In PBL, the final evaluation at the end of therapy with FDG-PET should be evaluated using Deauville 5-point scale in order to significantly reduce the risk of false-positive scans.

Imaging of pathology involving the space around the hepatic veins: "perivenous pattern"

We aimed to illustrate diseases involving the potential space around the hepatic veins. Perivenous halo sign can be seen in patients with congestive heart failure or fluid overload. Perivenous involvement can be observed in patients with alcoholic fatty liver disease, which can be focal or diffuse. Metastasis and primary liver tumor spread can also involve this space most likely due to involvement of lymphatics around hepatic veins.

Discriminatory CT-textural features in splenic infiltration of lymphoma versus splenomegaly in liver cirrhosis versus normal spleens in controls and evaluation of their role for longitudinal lymphoma monitoring

PURPOSE

To find CT-texture analysis (CTTA) features for the discrimination of splenomegaly due to diffuse lymphoma involvement and liver cirrhosis versus normal-sized spleens in controls and to assess their potential role for longitudinal lymphoma monitoring.

MATERIAL AND METHODS

We had retrospectively identified 74 subjects with diffuse splenic involvement due to lymphoma (n = 29) and liver cirrhosis (n = 30), and healthy controls (n = 15), who underwent contrast-enhanced abdominal CT between August 2013 and October 2017. CTTA evaluation included heterogeneity, intensity, average, deviation, skewness, entropy of co-occurrence, number non-uniformity (NGLDM) and entropy NGLDM. A greater than 50% reduction of spleen volume after chemotherapy was considered proof for splenic involvement.

RESULTS

There were significant differences of splenic CTTA-values before and after treatment of patients with lymphoma, including mean of entropy(p < .001), uniformity of average(p < .001), uniformity of deviation(p = .002) and entropy of skewness(p < .001). Significant differences of splenic CTTA-values in subjects with lymphoma vs. healthy controls were found for mean intensity(p < .001), mean average(p < .001), and entropy of deviation(p < .001). No significant differences in splenic CTTA-values were found in subjects with lymphoma that reached complete remission vs. controls. Splenic CTTA values mean intensity(p = .002) and mean average(p = .004) were significantly different between subjects with untreated lymphoma and subjects with liver cirrhosis. At end-of-treatment all lymphomas reached complete remission. Entropy/uniformity of heterogeneity(p < .001), mean intensity(p = .007), mean average (p = .007), uniformity of average(p = .008) and mean/entropy/uniformity of skewness(p = .001) measured at this time differed significantly from baseline.

CONCLUSIONS

CTTA features in subjects with splenomegaly due to lymphoma and liver cirrhosis differ significantly from those of healthy controls and can be also used for monitoring lymphoma treatment. Quantitative CTTA features may increase the accuracy of diagnosing causes of splenomegaly.

Extranodal lymphomas of abdomen and pelvis: imaging findings and differential diagnosis

A wide spectrum of extranodal lymphomas in the abdomen and pelvis is commonly encountered by imaging. Diagnosing these lesions generally requires a multimodality approach. This review highlights imaging appearances of extranodal lymphomas in the abdomen and pelvis with emphasis on computed tomography, magnetic resonance imaging, and positron emission tomography-computed tomography along with the relevant differential diagnosis.

Radiographic Enlargement of Mandibular Canal as an Extranodal Primary Non-Hodgkin's Lymphoma Early Sign in an Asymptomatic Patient

Non-Hodgkin's lymphoma (NHL) is a lymphoproliferative disorder, from a subgroup of heterogeneous hematologic malignancies; the term “extranodal” refers to malignant involvement of tissues other than lymph nodes, tonsils, spleen, pharyngeal lymphatic ring, or thymus. Only 0.6% of all NHL are at mandible alone, and it may involve the inferior alveolar canal. We describe a case of bilateral enlargement of the mandibular canal without symptomatology, which was shown in a panoramic radiograph and cone beam computed tomography in a rehabilitation routine exam, as an early sign of primary extranodal NHL.

Imaging features of Burkitt lymphoma in pediatric patients

Burkitt lymphoma is an aggressive and rapidly growing tumor that is curable and highly sensitive to chemotherapy. It can affect almost every tissue in the body, producing various clinical presentations and imaging appearances, according to the predilection of the different subtypes for certain sites. Awareness of its diagnostically specific imaging appearances plays an important role in rapid detection and treatment. In this pictorial review, we aimed to identify the most common imaging features of Burkitt lymphoma in pediatric patients.

Imaging of Extranodal Genitourinary Lymphoma

The genitourinary (GU) system is commonly affected by disseminated lymphoma. Rarely, lymphoma can originate from and remain localized to one of the GU organs and thus presents as primary extranodal disease. Up to 40% of lymphomas present as extranodal disease, with only 3% having the GU system as the primary site of involvement. This article describes and correlates the radiologic and pathologic features of extranodal lymphomatous disease affecting the GU system with specific focus on the kidneys, adrenal glands, testicles, and ovaries. Lymphoma of the uterine body and cervix, external female genitalia, urinary bladder, and prostate gland is briefly discussed.

Abdominal manifestations of extranodal lymphoma: pictorial essay

In the appropriate clinical setting, certain aspects of extranodal abdominal lymphoma, as revealed by current cross-sectional imaging techniques, should be considered potentially diagnostic and can hasten the diagnosis. In addition, diagnostic imaging in the context of biopsy-proven lymphoma can accurately stage the disease for its appropriate treatment. The purpose of this article was to illustrate the various imaging aspects of extranodal lymphoma in the abdomen.

Spectrum of Radiological Manifestations in Lymphoproliferative Malignancies with Unusual Extra Nodal Soft Tissue Involvement

Lymphoproliferative malignancies constitute a wide spectrum of haematological malignancies and their prevalence is widely increasing. Non-Hodgkin lymphomas and Hodgkin disease, frequently involve extranodal soft tissue structures in the head and neck, thorax and abdomen. These malignancies may involve virtually any type of soft tissues to any extent; hence many different imaging manifestations are possible which may mimic other disorders. The imaging characteristics of extranodal lymphomatous soft tissue involvement are described and classified here according to the site of involvement in 6 cases (primary diseases with orbital, muscle, extra testicular, scalp, sinonasal and pachymeningeal/dural involvement). In majority of these cases at presentation we found a predominantly homogeneous soft tissue mass with mildly high attenuation on CT and a T2 intermediate signal on MRI at these sites without any manifestation of disease elsewhere but on follow-up two out of these six cases developed systemic disease elsewhere. Few consistent patterns were noticed on CT and MRI which might help to include lymphomas as an important differential diagnosis of soft tissue masses. Though a definitive diagnosis requires a biopsy (bone marrow, lymph node, or mass), and other laboratory tests, imaging primarily aims at staging of the disease and identification of new or recurrent disease.

Diffuse Infiltrative Splenic Lymphoma: Diagnostic Efficacy of Arterial-Phase CT

Objective

To evaluate the diagnostic performance of obliteration of normal heterogeneous enhancement of the spleen (ONHES) on arterial phase (AP) computed tomography (CT) images in diffuse infiltrative splenic lymphoma (DISL).

Materials and Methods

One hundred and thirty-six patients with lymphoma who had undergone two-phase (arterial and portal venous) abdominal CT were included in this study. We retrospectively evaluated the diagnostic performance of ONHES on AP CT in diagnosing DISL. Two observers evaluated ONHES on AP CT using the 5-point confidence level and assessed the presence or absence of subjective splenomegaly on axial CT images. Another two observers measured the splenic index as proposed by objective CT criteria. Statistical analysis included interobserver agreement and diagnostic performance of CT findings.

Results

Eleven of the 136 patients with lymphoma had DISL. The area under the receiver operating characteristic curve of ONHES (0.948 for observer 1 and 0.922 for observer 2) was superior to that of the splenic index (0.872 for observer 3 and 0.877 for observer 4), but the difference was not statistically significant (p > 0.05). The diagnostic performance of ONHES in conjunction with subjective splenomegaly showed higher diagnostic performance, as compared with subjective splenomegaly alone (accuracy: 100% and 85.3% for observer 1, 98.5% and 87.5% for observer 2; positive predictive value: 100% and 35.5% for observer 1, 90.9% and 39.3% for observer 2, respectively).

Conclusion

Obliteration of normal heterogeneous enhancement of the spleen in conjunction with subjective splenomegaly can improve the diagnostic performance for DISL. Our results suggest that ONHES on AP CT images could be useful as an adjunctive diagnostic indicator of DISL in patients with lymphoma.

Perirenal Involvement of Mantle Cell Lymphoma: Imaging Features

Perirenal lymphoma is a rare disease and accounts for less than 10% of all malignant lymphomas. Mantle cell lymphoma (MCL) is the rarest but 1 of the most aggressive non-Hodgkin's lymphoma subtype. The perirenal involvement of MCL has not been reported previously. A 69-year-old male, who had been diagnosed as having MCL 1 year ago, presented with recent-onset right back pain. Herein we present the key imaging findings of perirenal soft tissue manifestation of MCL.

Unusual childhood presentations of abdominal non-Hodgkin's lymphoma

Non-Hodgkin's lymphoma (NHL) is a relatively common childhood cancer that can present in a myriad of ways. It is essential that NHL is included in the differential diagnosis of children presenting with an abdominal complaint, especially those with unexplained or prolonged symptoms. We describe three acute pediatric presentations of abdominal NHL, two of which presented as acute abdomen (the first mimicking intussusception and the second appendicitis), and the third involving lower limb edema. This case series illustrates the array of presentations of abdominal NHL and the diagnostic challenges that they can provide.

Hematologic malignancies of the liver: spectrum of disease

The incidence of hematologic malignancies and their extranodal manifestations is continuously increasing. Previously unsuspected hepatic involvement in hematologic malignancies such as Hodgkin disease and non-Hodgkin lymphoma, posttransplant lymphoproliferative disorder, myeloid sarcoma (chloroma), multiple myeloma, Castleman disease, and lymphohistiocytosis may be seen by radiologists. Although the imaging features of more common hepatic diseases such as hepatocellular carcinoma, metastases, and infection may overlap with those of hepatic hematologic malignancies, combining the imaging features with clinical manifestations and laboratory findings can facilitate correct diagnosis. Clinical features that suggest a hematologic neoplasm as the cause of liver lesions include a young patient (<40 years of age), no known history of cancer, abnormal bone marrow biopsy results, fever of unknown origin, and night sweats. Imaging features that suggest hematologic malignancy include hepatosplenomegaly or splenic lesions, vascular encasement by a tumor without occlusion or thrombosis, an infiltrating mass at the hepatic hilum with no biliary obstruction, and widespread adenopathy above and below the diaphragm. Familiarity with the imaging features of hepatic hematologic malignancies permits correct provisional diagnosis and may influence therapeutic management. For example, when biopsy is performed, core biopsy may be needed in addition to fine-needle aspiration so that the tissue architecture of the neoplasm can be discerned. The predominant treatment of hematologic malignancies is chemotherapy or radiation therapy rather than surgery. Online supplemental material is available for this article.

Imaging features of haematological malignancies of kidneys

Haematological malignancies are relatively uncommon neoplasms of kidneys. Nevertheless, the incidence of these neoplasms is increasing, partly due to more widespread use of computed tomography and magnetic resonance imaging. This article discusses the clinical and imaging features of renal lymphoma, leukaemia, extra-osseous multiple myeloma, and post-transplant lymphoproliferative disorder. Although there is overlap of imaging features with other more common malignancies, such as transitional and renal cell cancers, the combination of imaging findings and the appropriate clinical picture should allow the radiologist to raise a provisional diagnosis of a haematological neoplasm. This has management implications including the preference for image-guided core biopsies and a shift towards medical rather than surgical therapy.

Imaging findings for intravascular large B-cell lymphoma of the liver

Intravascular large B-cell lymphoma (IVLBCL) is a rare subtype of extranodal diffuse large B-cell lymphoma that most commonly involves the central nervous system and skin. To our knowledge, no state-of-the art imaging findings have been reported for hepatic IVLBCL in the English literature. We report the first case of hepatic involvement of IVLBCL along with a literature review.

Fluorine-18 fluorodeoxyglucose PET-CT for extranodal staging of non-Hodgkin and Hodgkin lymphoma

PURPOSE

We aimed to evaluate the role of fluorine-18 fluorodeoxyglucose positron emission tomography-computed tomography (18F-FDG PET-CT) involving care-dose unenhanced CT to detect extranodal involvement in patients with non-Hodgkin and Hodgkin lymphoma.

MATERIALS AND METHODS

Lymphoma patients (35 Hodgkin lymphoma, 75 non-Hodgkin lymphoma) who were referred for 18F-FDG PET-CT imaging, following a diagnostic contrast-enhanced CT (CE-CT) performed within the last month, were included in our study. A total of 129 PET-CT images, and all radiologic, clinical, and pathological records of these patients were retrospectively reviewed.

RESULTS

In total, 137 hypermetabolic extranodal infiltration sites were detected by 18F-FDG PET-CT in 62 of 110 patients. There were no positive findings by CE-CT that reflected organ involvement in 40 of 137 18F-FDG-positive sites. The κ statistics revealed fair agreement between PET-CT and CE-CT for the detection of extranodal involvement (κ=0.60). The organs showing a disagreement between the two modalities were the spleen, bone marrow, bone, and thyroid and prostate glands. In all lesions that were negative at CE-CT, there was a diffuse 18F-FDG uptake pattern in the PET-CT images. The frequency of extranodal involvement was 51% and 58% in Hodgkin and non-Hodgkin lymphoma patients, respectively. There was a high positive correlation between the maximum standardized uptake values of the highest 18F-FDG-accumulating lymph nodes and extranodal sites (r=0.67) in patients with nodal and extranodal involvement.

CONCLUSION

18F-FDG PET-CT is a more effective technique than CE-CT for the evaluation of extranodal involvement in Hodgkin and non-Hodgkin lymphoma patients. PET-CT has a significant advantage for the diagnosis of diffusely infiltrating organs without mass lesions or contrast enhancement compared to CE-CT.

Primary lymphomas of the female genital tract: imaging findings

Primary lymphomas of the female genital tract are extremely rare, and a definitive diagnosis requires correlation of the clinical, radiological, and pathological findings. Unlike nonlymphomatous malignant tumors, the treatment of lymphoma is typically nonsurgical, thus raising the possibility of lymphoma in the differential diagnosis of a pelvic mass, a radiologist can significantly change the approach to the disease. Although some imaging findings may appear nonspecific, others may suggest the possibility of lymphoma, such as the presence of one or more solid, well-defined, homogeneous masses without necrosis despite a large size or the presence of diffuse infiltration leading to organomegaly with architectural preservation. Additionally, pelvic lymphadenopathy may be evident. In this pictorial essay, we discuss the radiological appearances of gynecological primary lymphomas, grouped by organ, in ultrasonography, computed tomography, and magnetic resonance imaging.

From the radiologic pathology archives: Adrenal tumors and tumor-like conditions in the adult: radiologic-pathologic correlation

Advanced imaging often reveals adrenal tumors and tumor-like conditions in both symptomatic and asymptomatic patients. When adrenal disease is clinically suspected, cross-sectional imaging can be helpful in evaluating the etiology of the patient's symptoms. When adrenal disease is incidentally identified, what the clinician and patient really want to know is whether the findings are benign or malignant, as this ultimately will affect their next step in management. Using radiologic-pathologic correlation, we broadly classify common, uncommon, and rare tumors and tumor-like conditions that can occur in the adrenal as benign or malignant. This classification follows predominant trends in observed biologic behavior while acknowledging those tumors that may behave in the minority in an unpredictable manner. We review the clinical background and presentation of functional adrenal tumors including Conn syndrome, Cushing syndrome, and catecholamine-secreting tumors, as well as their relationship with adrenal anatomy. We discuss a variety of benign tumors, including adrenal cortical adenoma (including oncocytoma) and pheochromocytoma, as well as uncommonly and rarely encountered tumors such as myelolipoma, hemangioma, lymphangioma, schwannoma, ganglioneuroma, and adenomatoid tumor. A variety of tumefactive but nonneoplastic lesions are addressed, including adrenal cortical hyperplasia, adrenal hemorrhage, adrenal cysts, and infections. Malignant tumors discussed include adrenal cortical carcinoma, the rare malignant pheochromocytoma, lymphoma, metastases, and sarcomas. For each tumor and tumor-like lesion, the clinical presentation, epidemiology, key imaging findings, diagnostic differential considerations, and management options are briefly addressed. Finally, an approach to the workup of suspected or incidentally discovered tumors is presented based on a selected literature survey and our clinical experience. Radiologists play an important role in identification and diagnosis of adrenal tumors and tumor-like conditions in both symptomatic and asymptomatic patients.

Development and translational imaging of a TP53 porcine tumorigenesis model

Cancer is the second deadliest disease in the United States, necessitating improvements in tumor diagnosis and treatment. Current model systems of cancer are informative, but translating promising imaging approaches and therapies to clinical practice has been challenging. In particular, the lack of a large-animal model that accurately mimics human cancer has been a major barrier to the development of effective diagnostic tools along with surgical and therapeutic interventions. Here, we developed a genetically modified porcine model of cancer in which animals express a mutation in TP53 (which encodes p53) that is orthologous to one commonly found in humans (R175H in people, R167H in pigs). TP53(R167H/R167H) mutant pigs primarily developed lymphomas and osteogenic tumors, recapitulating the tumor types observed in mice and humans expressing orthologous TP53 mutant alleles. CT and MRI imaging data effectively detected developing tumors, which were validated by histopathological evaluation after necropsy. Molecular genetic analyses confirmed that these animals expressed the R167H mutant p53, and evaluation of tumors revealed characteristic chromosomal instability. Together, these results demonstrated that TP53(R167H/R167H) pigs represent a large-animal tumor model that replicates the human condition. Our data further suggest that this model will be uniquely suited for developing clinically relevant, noninvasive imaging approaches to facilitate earlier detection, diagnosis, and treatment of human cancers.

Adult abdominal Burkitt lymphoma with isolated peritoneal involvement

Burkitt lymphoma is a fast-growing high grade B-cell neoplasm that rarely affects adults. Three clinical variants are described in the World Health Organization classification: endemic, sporadic, and immunodeficiency-associated. The non-endemic form typically presents as an abdominal mass in children. Symptoms usually occur due to mass effect or direct intestinal involvement. We describe a very unusual presentation of a sporadic Burkitt lymphoma case in a 61-year-old male with diffuse peritoneal and omental involvement, without lymphadenopathies, mimicking peritoneal carcinomatosis.

Renal and urologic disorders in antiretroviral-treated patients with HIV infection or AIDS: spectrum of cross-sectional imaging findings

In the aging human immunodeficiency virus (HIV)-infected population with improved immune function under antiretroviral treatment, many different opportunistic disorders may be encountered, along with rare presentations or complicated forms of common diseases. Renal and urologic abnormalities observed in the setting of HIV infection or acquired immunodeficiency syndrome are reviewed with their imaging appearances, including renal dysfunction, urolithiasis, urinary tract infections and related complications, genitourinary tuberculosis, vascular lesions, urogenital tumors, and bladder abnormalities, with emphasis on characterization. In HIV-positive patients, early cross-sectional imaging is warranted to detect uncommon disorders and complications, with the aim to preserve renal function.

Imaging findings of primary splenic lymphoma: a review of 17 cases in which diagnosis was made at splenectomy

Purpose

This study sought to characterize the imaging features of primary splenic lymphoma (PSL).

Materials and Methods

Pathological and imaging data from 17 patients with primary splenic lymphoma initially diagnosed at splenectomy were retrospectively analyzed. Pretreatment computed tomography (CT) imaging was available for 16 patients, and magnetic resonance imaging (MRI) data were available for 4 patients. Splenic lymphoma imaging data were categorized based on the gross pathological presentation in the following manner: type 1, homogeneous enlargement; type 2, miliary nodules; type 3, multifocal masses of varying size; and type 4, solitary large mass.

Results

Of the 17 patients with PSL, 16 cases were non-Hodgkin lymphoma, and of these, 9 cases were diffuse large B cell lymphomas (DLBCL) and 4 cases were splenic marginal zone B-cell lymphoma (SMZL). Imaging showed the following types of PSL presentation: 1 case of type 1, 0 cases of type 2, 4 cases of type 3, and 12 cases of type 4. There was evidence of necrosis in 12 cases (70.6%), and there was evidence of mild enhancement in enhanced CT in 14 cases and in enhanced MRI in 3 cases. Prior to surgery, PSL was considered possible in 8 patients.

Conclusion

The most frequent histological subtype was DLBCL, followed by SMZL. In both CT and MRI, PSL generally presents as a solitary mass or masses rather than as splenomegaly. In addition, necrosis and mild enhancement are commonly observed, and splenectomy may be required to confirm the diagnosis.

Primary gynecologic lymphoma: imaging findings

OBJECTIVE

The purpose of this article is to review the imaging features, particularly on MR images, useful in identifying primary gynecologic lymphoma.

CONCLUSION

Primary gynecologic lymphoma is rare. Nonetheless, the distinction between primary and secondary involvement is important because of critical differences in prognosis and treatment. The prospective diagnosis of primary gynecologic lymphoma enables immediate chemotherapy or radiation therapy and avoids unnecessary surgery, which delays treatment. Diagnostic imaging can be key in differentiating lymphoma from the far more common pelvic malignancies.

Abdominal manifestations of lymphoma: spectrum of imaging features

Non-Hodgkin and Hodgkin lymphomas frequently involve many structures in the abdomen and pelvis. Extranodal disease is more common with Non-Hodgkin's lymphoma than with Hodgkin's lymphoma. Though it may be part of a systemic lymphoma, single onset of nodal lymphoma is not rare. Extranodal lymphoma has been described in virtually every organ and tissue. In decreasing order of frequency, the spleen, liver, gastrointestinal tract, pancreas, abdominal wall, genitourinary tract, adrenal, peritoneal cavity, and biliary tract are involved. The purpose of this review is to discuss and illustrate the spectrum of appearances of nodal and extranodal lymphomas, including AIDS-related lymphomas, in the abdominopelvic region using a multimodality approach, especially cross-sectional imaging techniques. The most common radiologic patterns of involvement are illustrated. Familiarity with the imaging manifestations that are diagnostically specific for lymphoma is important because imaging plays an important role in the noninvasive management of disease.