Small intestinal follicular lymphoma induced by methotrexate: a case report.

BACKGROUND: Methotrexate-associated lymphoproliferative disorder (MTX-LPD) is a rare but critical complication that develops in patients treated with MTX. Although MTX-LPD has been recently reported, the incidence of follicular lymphoma in the intestine is very low. CASE PRESENTATION: A 73-year-old woman who had been receiving MTX for over 10 years visited our hospital complaining of postprandial abdominal pain and nausea. Upper and lower digestive tract endoscopies did not show any abnormal findings. A patency capsule was stagnated at the proximal part of the ileum with a mild dilation on the oral side. An oral balloon endoscopy revealed shallow ulcerative lesions in the jejunum. She was diagnosed with MTX-LPD based on histopathological findings. The symptoms did not improve with the discontinuation of MTX, and the patient required partial resection of the small intestine. The test result for Epstein-Barr virus-encoded small RNA was negative. She was diagnosed with follicular lymphoma based on the histology findings of a surgical specimen. Postoperative positron emission tomography-computed tomography and bone marrow aspiration did not show any findings of lymphoma. On follow-up, no recurrence was noted four years after the surgery. CONCLUSIONS: Herein, we report the first case of follicular lymphoma that occurred in the small intestine, negative for Epstein-Barr virus-encoded small RNA. If intestinal symptoms occur during MTX administration, it is important to directly observe by endoscopy and perform histological examination.

Unilateral drainage and chemotherapy prolong the patency of a plastic stent placed above the sphincter of Oddi in patients with malignant hilar biliary obstruction.

Objectives: To evaluate the results of inside stent therapy for unresectable malignant hilar biliary obstruction and identify factors related to stent patency duration. Methods: Of 44 patients who underwent initial inside-stent placement above the sphincter of Oddi from April 2017 to December 2022, 42 with the resolution of jaundice (clinical success rate, 95.5%) were retrospectively analyzed. Univariate and multivariate logistic regression analysis identified factors associated with stent patency duration. Results: Univariate analysis revealed significant differences in the drainage method (406 days for unilateral drainage vs. 305 days for bilateral drainage of the right and left liver lobes, p = 0.022) with or without chemotherapy (406 days with vs. 154 days without, p = 0.038). Multivariate analysis (Cox proportional hazards analysis) revealed similar results, with unilateral drainage (p = 0.031) and chemotherapy (p = 0.048) identified as independent factors associated with prolonged stent patency. Early adverse events were observed in two patients (4.8%; one cholangitis, one pancreatitis). Conclusions: Inside-stent therapy was safely performed in patients with malignant hilar biliary obstruction. Simple unilateral drainage and chemotherapy may prolong stent patency.