CASE REPORT

A 73-year-old caucasian male with a medical history of ulcerative proctitis (treated with mesalazine 3g/day) and gastroesophageal reflux disease (treated with omeprazol 20mg/day) was referred to our center due to epigastric discomfort. He was submitted to an upper endoscopy, which showed a peripapillary duodenal polypoid mass with approximately 30mm. Endoscopic biopsy showed a mixed inflammatory infiltrate and fibronecrotic tissue. A magnetic resonance cholangiopancreatography (MRCP) and an endoscopic examination with a duodenoscope were requested and were consistent with a subepithelial lesion located about 8mm from the papilla of Vater. New biopsies were taken, revealing the same findings. Apart from a mild lymphocytosis (3,66 x 109/L), laboratory tests were unremarkable (including CEA, CA 19.9, bilirubin, alkaline phosphatase and gama-glutamyl transferase). An endoscopic ultrasound was carried out, which identified a 30mm homogeneous hypoechoic lesion in the second part of the duodenum, not related to the papilla, arising in the 4th duodenal wall layer (muscularis propria), without invasion of adjacent layers (Figure 1 A-C).

Figure 1: Homogeneous and hypoechoic lesion in the second part of the duodenum, arising in the 4th wall layer, observed on radial (A) and linear (B) endoscopic ultrasonography (EUS); the ampulla of Vater was normal (C).

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) was performed (22G needle, 3 passes) providing samples for conventional smear, liquid-based cytology (ThinPrep CytoLyt®) and into a 10% formalin solution (Figure 2).

Figure 2: EUS-FNA of the lesion.

Cytological analysis was compatible with a primary duodenal follicular lymphoma (Figure 3).

Figure 3: Histopathological examination showing small to medium lymphocytes with rare nucleoli (A and B) whose immunohistochemistry (IHC) study was compatible with follicular lymphoma (C – Bcl2+, D – CD10+).

The patient underwent therapy with rituximab and is currently in clinical remission with 5 months of follow-up.

Commentary
Small bowel malignancies comprise less than 2% of all gastrointestinal neoplasms, and only about a fifth correspond to primary gastrointestinal lymphomas (PGL).¹ Moreover, both the follicular subtype and the duodenal location are rare (1-4% and 6-8% of all PGL, respectively).² However, when follicular PGL occur, there’s a predilection for the duodenum (35% of the duodenal lymphomas are of the follicular subtype), with some authors recognizing this close association as corresponding to a distinct entity with specific immunophenotypic and behavioral features.^3-5 In the present case, with an initial suspicion of an epithelial or mesenchymal tumour, endoscopic ultrasound-guided fine-needle aspiration was crucial to provide an unusual histopathological diagnosis, defining a proper therapeutic strategy and avoiding a potentially unnecessary aggressive surgical procedure.

References

1. Ghimire P, Wu GY, Zhu L. Primary gastrointestinal lymphoma. World J Gastroenterol. 2011; Feb(14);17(6):697-707
2. Graham R, Mardones MA, Krause JR. Primary follicular lymphoma of the duodenum. Proc Bayl Univ Med Cent. 2015; 28(3):381–383
3. Dickson BC, Serra S, Chetty R. Primary gastrointestinal tract lymphoma: diagnosis and management of common neoplasms. Expert Rev Anticancer Ther. 2006; 6:1609-1628
4. Sentani K, Maeshima AM, Nomoto J, et al. Follicular Lymphoma of the Duodenum: A Clinicopathologic Analysis of 26 Cases. Jpn J Clin Oncol. 2008;38(8)547– 552
5. Schmatz AI, Kretschmer-Chott E, Puspok A, et al. Primary Follicular Lymphoma of the Duodenum Is a Distinct Mucosal/Submucosal Variant of Follicular Lymphoma: A Retrospective Study of 63 Cases . J Clin Onc. 2011; 26(11)

Authors

Carlos Bernardes1, Rafaela Loureiro¹, Sara Santos¹, Diana Carvalho¹, Mário Oliveira², Luís Mascarenhas², Emanuel Vigia³, Gonçalo Ramos¹
1 – Serviço de Gastrenterologia, CH Lisboa Central;
2 – Serviço de Anatomia Patológica, CH Lisboa Central;
3 – Serviço de Cirurgia Hepato-Bílio-Pancreática, CH Lisboa Central.