Hideki Machishi

A rare case of huge gastrointestinal stromal tumor (GIST) of the stomach extending into the posterior mediastinum.

It has recently been proposed that tumors deriving from mesenchymal cells of the gastrointestinal wall be given the general name gastrointestinal stromal tumor (GIST). Based on analysis of the immunohistochemical and electron microscopic findings, Rosai (1) classified GISTs into four major types: (1) smooth muscle, (2) neural, (3) combined smooth muscle and neural, and (4) uncommitted. Many authors have reported using this classification to type tumors mainly by immunohistochemical analysis. When analyzed immunohistochemically, myogenic tumors are positive for desmin, vimentin, and -smooth muscle antigen (SMA), and neurogenic tumors are positive for S-100 protein and neuron-specific enolase (NSE) (1, 2). The biological behavior and outcome of GISTs can be difficult to predict, and many morphological prognostic indicators, such as size, mitotic count, cytologic grade, and tumor necrosis, have been reported (1, 2). However, it is difficult to make predictions on the basis of morphological prognostic indicators alone, and new parameters, including DNA content and proliferative index measurements such as the MIB-1 labeling index, have recently come into use as objective prognostic indicators (3, 4). In this report, we describe a case of a huge GIST of the stomach that had extended into the posterior mediastinum, a rare occurrence according to the literature. We completely resected the lesion and immunohistochemically characterized it ( -SMA, vimentin, NSE, S-100 protein) to evaluate the direction in which it was tending to differentiate, and assesed the prognostic indicators (morphological indicators, DNA content, and MIB-1 labeling index) in terms of prediction of the biological behavior and outcome.

A case of transverse colon cancer secondarily involving the liver, duodenum, and pancreas.

A 68-year-old woman presented with transverse colon cancer invading the liver, duodenum, and pancreas. The patient underwent a curative resection including a right hemicolectomy, partial hepatectomy, and pancreaticoduodenectomy (PD). The pathological examination showed adenocarcinoma of the colon with a direct extension into the duodenum, liver, and pancreas. Several lymph nodes were also involved. The patient is still alive and disease-free 2 years and 6 months after the operation. This case illustrates that even in patients with locally advanced colon cancer, a favorable prognosis can be obtained by aggressive surgery incorporating the resection of the adjacent involved organs.

Manual laparoscopy-assisted intraoperative reduction for adult ileocolic intussusception with ileal adenoma: A case report

Highlights • Adult intussusception is a rare condition with a pathological lead point.• Manual intraoperative reduction of adult intussusception is safe and can eliminate the need for extensive or invasive resection.• Laparoscopy is a beneficial and minimally invasive technique for patients with intussusception.

Anatomical hepatectomy for liver metastasis from rectal adenocarcinoma presenting with intrabiliary extension: a case report

Liver metastases from colorectal carcinoma commonly form nodular lesions in the liver parenchyma. We report a case of liver metastasis from rectal adenocarcinoma that extended predominantly into the bile duct. A 62-year-old Japanese man underwent low anterior resection for rectal adenocarcinoma 9 years ago. Approximately 3 years later, he underwent radiofrequency ablation therapy for a metastatic liver tumor. Nine years after surgery, a tumor in liver segment III exhibiting intrabiliary extension was discovered; it was unclear if this was a metastatic liver tumor or intrahepatic cholangiocarcinoma. Accordingly, we performed a left hepatectomy with lymph node dissection. The tumor was negative for cytokeratins 7 and 20, and was histologically similar to the primary rectal adenocarcinoma; it was diagnosed as rectal carcinoma metastasis. The patient has survived for 3 years after the hepatic surgery, for 9 years after radiofrequency ablation therapy, and for 12 years after the primary surgery. This case shows that liver metastasis from colorectal carcinoma can present as a predominantly intrabiliary growth that mimics intrahepatic cholangiocarcinoma on imaging. Moreover, our case provides evidence for the superiority of anatomical hepatectomy over partial hepatectomy for metastatic liver tumors with intrabiliary growth arising from rectal adenocarcinomas.