[Collision Tumor Involving Primary Ascending Colon Cancer and Malignant Lymphoma].

A 78-year-old male was diagnosed with a primary gastric B-cell malignant lymphoma and metastatic lung tumor 10 years ago. He underwent chemotherapy at another hospital, achieved complete remission, and was actively undergoing follow- up. He presented to our hospital with a 1-month history of a bulge in his right lower abdomen. CT revealed thickening of the ascending colon and dilatation of the oral intestine. He was diagnosed with ascending colon cancer and underwent right hemicolectomy. The subsequent pathological examination revealed a collision tumor involving diffuse, large B-cell lymphoma and well-differentiated adenocarcinoma. He was discharged from our hospital and received chemotherapy at another institution. Unfortunately, the patient died of interstitial pneumonia 31 months postoperatively. This report describes the resection of a collision tumor involving ascending colon cancer and malignant lymphoma. Surgical treatment combined with postoperative chemotherapy improved this patient's long-term survival.

[Laparoscopic Tumor Resection for Asymptomatic Paraganglioma-A Case Study].

A 55-year-old man was referred for the close examination of an abdominal mass noted on abdominal ultrasonography during a physical examination. A contrast-enhanced computed tomography(CT)scan of his abdomen revealed a 36-mm heterogeneously contrast-enhanced mass on the left side of the aorta. He was referred for laparoscopic tumor resection without preoperative histological examination. The tumor was identified from the dorsal aspect of the mesentery of the transverse colon and was resected only because it was detachable from the duodenum. A temporary abnormal hypertension was observed intraoperatively. However, he exhibited a favorable postoperative course and was discharged on the 8th postoperative day. Grossly, it was a nodular tumor with a diameter of 38 mm. Histopathological examination revealed that the tumor cells having abundant cytoplasm formed large foci and were surrounded by sinusoidal vessels. Immunohistochemistry results were positive for chromogranin A, synaptophysin, and neural cell adhesion molecule; thus, paraganglioma was diagnosed. Herein, we report a case of laparoscopic resection of an asymptomatic paraganglioma.

Effect of Notch expression in glioma stem cells on therapeutic response to chemo-radiotherapy in recurrent glioblastoma.

Glioma stem cells (GSCs) have the capacity to repopulate tumors and mediate resistance to radiotherapy and chemotherapy. The Notch signaling pathway is important in proliferation, stem cell maintenance, cell differentiation, and tumorigenesis in GSCs. In this study, we compared CD133, Notch, and VEGF expressions in histological sections of primary and recurrent glioblastomas after radiotherapy and chemotherapy. In vitro study, the γ-secretase inhibitor inhibited NICD, Hes1 and pVEGFR2 expressions in GSCs. GSCs cultured under endothelial conditions undergo endothelial differentiation. Tumor samples were collected from 27 patients at the time of tumor recurrence. We used immunohistochemical techniques to compare expression of CD133, Notch-1 and VEGF. Expressions of CD133-, Notch-1-, and VEGF-positive glioma cells were higher in recurrent glioblastoma after radiotherapy and chemotherapy. To determine the clinical importance of Notch-1 expression in glioblastoma, we analyzed 15 patients who had received bevacizumab therapy followed by a second surgery at recurrence. OS was significantly longer in cases with Notch-1 negativity (8.8 months) than in those with I Notch-1 positivity (6.8 months). We noted that GSCs have the potential for endothelial differentiation with Notch activity. We believe that Notch-1 is a potential target and/or biomarker for antiangiogenic treatments.

Multiple necrotic nodules of the liver simulating liver metastasis.

A 70-year-old man was referred to our hospital due to anemia and elevated serum tumor marker levels. He had advanced colon cancer, and hepatic lesions were found incidentally. On ultrasonography (US) and computed tomography (CT), the hepatic lesions had a maximum diameter of 20 mm and were located in Couinaud's segments V, VI, VII, and VIII, which suggested liver metastasis. On early- and late-phase CT during hepatic arteriography (CTHA), all of the lesions had rim enhancement. On early-phase CT during arterioportography (CTAP), all of the lesions were seen as nodules with an irregular perfusion defect, and on late-phase CTAP, all the lesions gradually became iso-dense, and their shape and size changed. Based on the CTAP findings, these lesions were thought to be fibrotic tumors. Partial resection of the liver (including the lesions in Couinaud's segments V and VIII) was done. Histological examination revealed that the lesions were necrotic nodules. Thus, CT angiography (CTHA and CTAP) was useful for identifying necrotic nodules, because their appearance on this modality is different from that of liver metastases.

Single case of renal cell carcinoma and endocrine pancreatic head cancer occurring with von Hippel-Lindau disease.

Von Hippel-Lindau (VHL) disease is an autosomal dominant genetic disease in which various neoplastic lesions occur in multiple organs. Reported here is a case of VHL disease with concurrent renal cell carcinoma and endocrine pancreatic cancer. The patient was a 43-year old woman. On this occasion, the patient had sought treatment from her local physician, complaining chiefly of yellowing of the skin and bulbar conjunctiva. Abdominal ultrasound and computed tomography scans revealed a mass in the right kidney and a mass in the pancreatic head. Peripheral blood genetic analysis revealed an Arg/stop heteroconjugative mutation in codon 113 in exon 1 of the VHL gene on the short arm of chromosome 3 (p25-26). After various tests were performed, the patient was diagnosed with right renal cell carcinoma, malignant tumor of the pancreatic head, and multiple pancreatic cysts accompanying von Hippel-Lindau disease. Right nephrectomy and pancreatoduodenectomy were performed. Based on the histopathological results, the patient was diagnosed with right renal cell carcinoma and highly differentiated endocrine pancreatic cancer. Immunohistologically, a large number of atypical cells were found to be positive for both anti-chromogranin and anti-synaptophysin antibodies in the endocrine tumor. Immunostaining for each type of gut hormone was also performed, but all results were negative. Based on the above findings, nonfunctioning, highly differentiating endocrine cancer was diagnosed. This is the first confirmed case of renal cell carcinoma and endocrine pancreatic cancer occurring concurrently with VHL. This is an important case, so it is presented here along with a short discussion of the literature.