Small Intestinal Adenocarcinoma Arising at the Anastomotic Site after Kasai Operation for Biliary Atresia: A Case Report and Literature Review.

Biliary atresia is an obliterative cholangiopathy of unknown etiology. Hepatic portoenterostomy, in which obliterated extrahepatic bile ducts are resected and bile flow is restored, known as Kasai operation, is performed within 3 months after birth. While this operation enhances long-term survival of patients, the occurrence of primary malignant hepatic tumors has been increasing. We report a case of small intestinal adenocarcinoma arising at the anastomotic site after Kasai operation. A 49-year-old man, who underwent Kasai operation for biliary atresia when he was 2 months old, experienced rapidly progressive jaundice and liver dysfunction. Deceased-donor liver transplantation was performed for liver failure. Macroscopically, there was a white-yellow tumor located at the anastomotic site of hepatic portoenterostomy of the resected liver. Pathological examination revealed a well-differentiated adenocarcinoma with some Paneth cells in the neoplastic lesion. Immunohistochemically, the tumor cells were negative for cytokeratin 7 (CK7) but positive for cytokeratin 20 (CK20) and a homeobox domain-containing transcription factor (CDX2). Mucin expression in tumor cells was negative for mucin 1 (MUC1) and mucin 6 (MUC6) and positive for mucin 2 (MUC2) and mucin 5AC (MUC5AC). The pathological diagnosis was small intestinal adenocarcinoma originating from the jejunum. The patient was discharged 48 days after the operation. The patient had not experienced recurrence at 10 months after the operation. This is the first report of small intestinal adenocarcinoma arising at the anastomotic site after Kasai operation for biliary atresia. Special care should be taken for the patients after Kasai operation with acute progressive jaundice and liver dysfunction because there is a possibility of malignancy in their native liver.

Ultra-High-Molecular-Weight Polyethylene Merlon Shape: Novel Fixation of Artificial Bone for Cranioplasty.

BACKGROUND: Cranioplasty is a surgical procedure widely performed for repairing cranial defects caused by external decompression surgery for cerebrovascular disease or traumatic brain injury. We devised a new cranioplasty method using artificial bone made up of ultra-high molecular-weight polyethylene, with serrated wings on the edge. We named this newly designed artificial bone as Merlon shape. OBJECTIVE: To describe our initial experience with the Merlon shape and evaluate its usefulness and safety in cranioplasty. METHODS: The serrated wings of the Merlon shape were preoperatively designed for solid fixation and improving cosmetic results by reducing the thickness of the artificial bone. We evaluated 25 patients who underwent cranioplasty with the Merlon shape between December 2018 and December 2021. The causes of bone defects in these patients (male: 9, female: 16; median age: 62 years) were subarachnoid hemorrhage (n = 14), cerebral infarction (n = 8), and traumatic brain injury (n = 3). RESULTS: There were no postoperative adverse events such as infection, bone resorption, implant exposure, or graft sinking in 24 patients during an average follow-up period of 19 months. One patient experienced acute epidural hemorrhage and required reoperation. CONCLUSION: This is the first report on the use of the ultra-high molecular-weight polyethylene Merlon shape. Our initial 4-year case series showed good outcomes with this method.