Giant cystic lymphangioma in the pancreatic tail–splenic hilum region managed by en bloc resection

Rationale: Lymphangioma is a benign lymphatic malformation that occurs predominantly in children and at superficial sites. Intra-abdominal lymphangioma is uncommon, and involvement of the pancreatic tail–splenic hilum region is particularly rare. Such lesions may mimic pancreatic or peripancreatic cystic disease, making preoperative diagnosis challenging. Patient concerns: We report a 43-year-old woman who presented with persistent dull left upper abdominal pain for 2 days. Laboratory tests showed nonspecific inflammatory and mild hepatobiliary abnormalities. Diagnoses: Ultrasonography and contrast-enhanced computed tomography demonstrated a giant multiloculated cystic lesion measuring approximately 160 × 110 mm and closely related to the pancreatic tail and splenic hilum. Histopathology demonstrated dilated endothelial-lined lymphatic spaces, and the written pathology report recorded D2-40 positivity, supporting the diagnosis of lymphangioma. Interventions: Exploratory laparotomy was performed. Because the lesion was densely adherent to the pancreatic tail and splenic hilum without a safe dissection plane, en bloc resection with distal pancreatectomy, splenectomy, and cholecystectomy was undertaken. Outcomes: Drain amylase was 1264 U/L on postoperative day 1 and 3337 U/L on postoperative day 3. The patient had no related symptoms, required no additional intervention, and had no delayed recovery, consistent with a biochemical leak under the 2016 International Study Group of Pancreatic Surgery definition. The drain was removed after ultrasonography showed no significant fluid collection, and the patient was discharged on postoperative day 11. Lessons: Lymphangioma should be considered in the differential diagnosis of giant multiloculated cystic lesions near the pancreatic tail and splenic hilum. When a symptomatic giant lesion cannot be safely separated from adjacent organs, complete en bloc resection may provide both definitive diagnosis and treatment.