[A Case of Resected Metachronous Pancreatic Metastasis from Rectal Carcinoma].

A 69-year-old man underwent a Miles operation with D3 lymph node dissection for rectal cancer. The pathological diagnosis was adenocarcinoma(Rb, A, ly2, v3, N2M0P0H0, Stage Ⅲb). Adjuvant chemotherapy was added for 6 months after the rectal resection. Metastasis in the left lung was detected 1 year and 10 months after rectal resection for which large segmental resection was performed. Without the onset of any new lesions, the patient underwent subsequent follow-up examinations. Abdominal CT performed for increased tumor marker levels observed at 6 years and 8 months after rectal resection revealed a mass suggestive of pancreatic ductal adenocarcinoma for which distal pancreatectomy was performed. The pathological diagnosis was metastasis to the pancreas from the rectal cancer as the tumor cells were immunohistochemically negative for cytokeratin 7 and positive for cytokeratin 20. There has been no indication of recurrence for 13 months after the pancreatic surgery. Resectable pancreatic metastasis from colorectal cancer is rarely reported. However, pancreatic resection may result in long-term survival in some cases. Patients that tolerate pancreatectomy and have no metastasis in the other organs should be considered good candidates for pancreatic resection. We present this case with a review of the literature.

[A Resected Case of Castleman's Disease That Was Difficult to Diagnose Preoperatively].

A 70-year-old man was referred to our hospital and admitted after abdominal computed tomography(CT)examination revealed a tumor in the retroperitoneum. The specific blood test findings were poor, and surveillance CT demonstrated a wellcircumscribed, enhanced mass measuring 40mm with calcification behind the horizontal portion of the duodenum. The tumor presented with a slightly high signal in low signal, T2 in T1, and it showed a diffusion decrease in DWI; the simple abdominal MRIrevealed heterogeneous accumulation of SUVmax 3.0 only for the lesion in FDG/PET-CT. Specific findings did not lead to a diagnosis, although EUS-FNA lower aspiration biopsy cytology was performed. Laparoscopic tumorectomy was performed to help determine the treatment strategy. Histopathological examination indicated that the tumor was composed of multiple lymph follicles with concentric layers of mantle zone cells, showing an onion skin-like lesion and atrophic germinal centers. The germinal centers had penetrating arterioles with hyalinized vessel walls, and Castleman's disease(hyaline vascular type)was therefore diagnosed. In this case, it was difficult to diagnose Castleman's disease before surgery. Surgical excision is a diagnostic as well as a curative method for management of this disease.