Clues for diagnosing primary pancreatic lymphoma

Primary Pancreatic Lymphoma in the Tail: A Rare Anatomic Presentation

Non-Hodgkin's lymphoma is a common type of cancer, whose most common site of extranodal involvement is the gastrointestinal tract. However, primary presentation in the pancreas remains uncommon. Among cases with pancreatic involvement, the disease is often found in the head and rarely in the tail. Here, we present a case of a 56-year-old male patient with acute epigastric pain, early satiety, and abdominal distention. CT imaging showed a mass of the pancreatic tail with surrounding lymphadenopathy, concerning lymphoma. Endoscopic ultrasound-guided fine needle aspiration (EUS-guided FNA) diagnosed mature B-cell lymphoma, meeting novel diagnostic criteria for the rare diagnosis of primary pancreatic lymphoma (PPL).

Primary Pancreatic Mantle Cell Lymphoma Diagnosed via Endoscopic Ultrasound-Guided Fine-Needle Aspiration

Primary pancreatic lymphomas (PPLs) are rare, and the histological classification of these tumors is difficult. To accurately diagnose and determine the appropriate treatment for PPLs, sufficient sample amounts are necessary. Here, we report a 73-year-old man with a primary pancreatic mantle cell lymphoma. Histological samples were obtained via endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). The tumor cells predominantly composed of atypical small to medium round cells, with diffuse immunoreactivity of CD20 and cyclin D1. In addition, immunoglobulin gene H chain rearrangement was detected. The patient underwent chemotherapy, resulting in complete remission. Eight years after the initiation of chemotherapy, the patient was still alive. EUS-FNA could be a useful and safe diagnostic modality for PPLs by providing enough samples for testing.

Features of primary pancreatic lymphoma: A bi-institutional review with an emphasis on typical and atypical imaging features

BACKGROUND

Primary pancreatic lymphoma (PPL) is a rare neoplasm. Being able to distinguish it from other pancreatic malignancies such as pancreatic ductal adenocarcinoma (PDAC) is important for appropriate management. Unlike PDAC, PPL is highly sensitive to chemotherapy and usually does not require surgery. Therefore, being able to identify PPL preoperatively will not only direct physicians towards the correct avenue of treatment, it will also avoid unnecessary surgical intervention.

AIM

To evaluate the typical and atypical multi-phasic computed tomography (CT) imaging features of PPL.

METHODS

A retrospective review was conducted of the clinical, radiological, and pathological records of all subjects with pathologically proven PPL who presented to our institutions between January 2000 and December 2020. Institutional review board approval was obtained for this investigation. The collected data were analyzed for subject demographics, clinical presentation, laboratory values, CT imaging features, and the treatment received. Presence of all CT imaging findings including size, site, morphology and imaging characteristics of PPL such as the presence or absence of nodal, vascular and ductal involvement in these subjects were recorded. Only those subjects who had a pre-treatment multiphasic CT of the abdomen were included in the study.

RESULTS

Twenty-nine cases of PPL were diagnosed between January 2000 and December 2020 (mean age 66 years; 13 males/16 females). All twenty-nine subjects were symptomatic but only 4 of the 29 subjects (14%) had B symptoms. Obstructive jaundice occurred in 24% of subjects. Elevated lactate dehydrogenase was seen in 81% of cases, whereas elevated cancer antigen 19-9 levels were present in only 10% of cases for which levels were recorded. The vast majority (90%) of tumors involved the pancreatic head and uncinate process. Mean tumor size was 7.8 cm (range, 4.0-13.8 cm). PPL presented homogenous hypoenhancement on CT in 72% of cases. Small volume peripancreatic lymphadenopathy was seen in 28% of subjects. Tumors demonstrated encasement of superior mesenteric vessels in 69% of cases but vascular stenosis or occlusion only manifested in 5 out of the twenty-nine individuals (17%). Mild pancreatic duct dilatation was also infrequent and seen in only 17% of cases, whereas common bile duct (CBD) dilation was seen in 41% of subjects. Necrosis occurred in 10% of cases. Size did not impact the prevalence of pancreatic and CBD dilation, necrosis, or mesenteric root infiltration (P = 0.525, P = 0.294, P = 0.543, and P = 0.097, respectively). Pancreatic atrophy was not present in any of the subjects.

CONCLUSION

PPL is an uncommon diagnosis best made preoperatively to avoid unnecessary surgery and ensure adequate treatment. In addition to the typical CT findings of PPL, such as homogeneous hypoenhancement, absence of vascular stenosis and occlusion despite encasement, and peripancreatic lymphadenopathy, this study highlighted many less typical findings, including small volume necrosis and pancreatic and bile duct dilation.

Primary Pancreatic Lymphoma: Recommendations for Diagnosis and Management

BACKGROUND

Primary pancreatic lymphoma (PPL) is a rare disease representing 0.1% of all malignant lymphomas, which lacks well-defined diagnostic and therapeutic protocols. We conducted a systematic review to analyze demographic, diagnostic and therapeutic features of PPL.

METHODS

This review identified small series and single case reports. Sources were MEDLINE, PubMed, and the Cochrane library from January 2001 to December 2020. Data were screened, extracted and the risk of bias analyzed by three independent reviewers.

RESULTS

A total of 107 eligible papers (17 small series, 90 single case reports) describing 266 patients were identified. Patients had a median age of 53.1 (range 3-86) years and were males in 64.6% of cases. Abdominal pain and jaundice were the most common presenting symptoms, affecting 75.3% and 41.8% of patients, respectively. PPL had a median size of 60.6 mm (range 16-200) and it was localized in the pancreatic head in 63.7% of cases. At diagnosis most patients underwent ultrasonography followed by computed tomography. PPL typically showed low echogenicity, and lower contrast enhancement than solid tumors. Histopathological specimens were obtained by percutaneous or endoscopic biopsies in 47.7% of patients; abdominal surgery was performed in 33.5% of cases. Overall, diffuse large B-cell lymphoma was the most frequent histological diagnosis (53.6%). However, patients aged <18 years were affected by Burkitt lymphoma in 52.4% of cases. Most patients (53.6%) received immunochemotherapy (IC) or IC plus radiotherapy (14%). Demolitive surgery appeared to be associated with impaired survival. Central nervous system (CNS) relapse or progression was observed in 20% of patients.

CONCLUSION

PPL is a rare entity, with some peculiar features at modern imaging. For diagnostic purposes percutaneous or endoscopic biopsies might be preferable, as opposed to surgery. No definite data is available about the optimal treatment, which should be tailored on the histological type and associated with CNS prophylaxis.

Pancreatic lymphoma: A cytologic diagnosis challenge

Very rarely lymphoma primarily or secondarily involves the pancreas. Involvement of the pancreatic parenchyma with lymphoma clinically may mimic pancreatic ductal adenocarcinoma (PDA) and other mass-forming pancreatic lesions. Endoscopic ultrasound fine needle aspiration (EUS-FNA) is the first step in the diagnostic pathway of managing these patients by providing a cytology specimen. Cytologically, lymphoma of pancreas can be misdiagnosed for a wide variety of pancreatic neoplastic and non-neoplastic lesions. Cytological differential diagnosis includes well-differentiated adenocarcinoma, acinar cell carcinoma, well differentiated neuroendocrine tumor, and autoimmune pancreatitis. Gastroenterologist's skills in providing adequate sample for preparing smears, cell blocks and/or performing flow cytometry, and also cytopathologist's skills in detecting atypical lymphocytic population are crucial factors. Although cytology examination has limitations to subclassify lymphoma, it plays a key role to redirect clinicians into the right patient-care pathway. In this article, we present two cases of pancreatic lymphoma with emphasis on the discriminating cytomorphological features, and we also review literatures with reports of primary pancreatic lymphoma (PPL) to better understand the characteristics of this rare lesion.

Clinicopathological characteristics of primary pancreatic lymphoma: report of two cases

Primary pancreatic lymphoma (PPL), originating from the pancreatic parenchyma, is a rare type of lymphoma. The symptoms and radiographic findings of PPL are quite similar to pancreatic adenocarcinoma (PAC), and thus it is often misdiagnosed. In this study, we described the clinical features, radiographic findings, histological and immunohistochemical analysis, molecular detection and clinical treatment of two cases of PPL, aiming to distinguish PPL from PAC. The two cases were both low-grade PPL. One was follicular lymphoma and the other was small lymphocytic lymphoma. Imaging examination of the two cases both showed solid mass, thus highly suspecting of PAC. However, after surgery, PPL was diagnosed by the pathologists through histopathological observation, immunohistochemistry (IHC) assay and clonality analysis. Therefore, accurately diagnosing and classifying of PPL is essential for patient management, since PPL is a treatable malignant tumor.

Primary pancreatic lymphoma: what we need to know

Hodgkin's lymphoma is a group of malignant lymphoid which involve various organs including gastrointestinal tract. Stomach and small intestine are commonly involved more; however, pancreas can be primarily involved as well. The secondary involvement of pancreas caused by Hodgkin's lymphoma is more prevalent than the primarily involvement (1 .25-2.2% vs. <1%). Primary pancreatic lymphomas (PPLs) consist of 1-2% of all lymphoma outside nods. The symptoms and findings of PPL imaging can be akin to that of pancreas adenocarcinoma and differentiating them is difficult without examining the tissue sample. The prognosis and treatment of PPL are different from those of adenocarcinoma and due to the superior prognosis of PPL compared to pancreas adenocarcinoma, the proper diagnosis of the disease is important.

A Man with Pancreatic Head Mass Lesion on Endoscopic Ultrasound and Granuloma on Cytopathology

Primary pancreatic lymphoma is an unlikely malignancy accounting for less than 0.5% of pancreatic tumors. Clinical presentation is often nonspecific and may be clinically misdiagnosed as pancreatic adenocarcinoma. Here we present an Iranian case of primary pancreatic lymphoma in a 47-year-old male suffering from jaundice and 20% weight loss. Endoscopic ultrasound revealed a mixed echoic mass lesion at the head of pancreas. The patient underwent endoscopic ultrasound-guided fine needle aspiration of solid pancreatic mass and histopathologic diagnosis revealed granuloma. Computed tomography-guided core needle biopsy was performed and eventually histological examination showed granuloma that was coherent with the diagnosis of primary pancreatic lymphoma. Primary pancreatic lymphoma is a rare entity presenting with nonspecific symptoms, laboratory and radiological findings. Computed tomography results in combination with clinical and radiological studies generally provide guidance for appropriate investigation.