A case of a duodenal duplication cyst presenting as melena.

Duodenal duplication cysts are benign rare congenital anomalies reported mainly in the pediatric population, but seldom in adults. Symptoms depend on the type and location and can present as abdominal pain, distension, dysphagia or dyspepsia. They have been reported to be responsible for duodenal obstruction, pancreatitis and, in rare cases, gastrointestinal bleeding. We present a case of a duodenal duplication cyst in a 43-year-old man presenting as melena. Initial gastroduodenoscopy and colonoscopy did not reveal any bleeding focus. However, the patient began passing melena after 3 d, with an acute decrease in hemoglobin levels. Subsequent studies revealed a duplication cyst in the second portion of the duodenum which was surgically resected. Histology revealed a duodenal duplication cyst consisting of intestinal mucosa. There was no further bleeding and the patient recovered completely. In rare cases, duodenal duplication cysts might cause gastrointestinal bleeding and should be included in the differential diagnosis.

EGFR mutation status in primary lung adenocarcinomas and corresponding metastatic lesions: discordance in pleural metastases.

UNLABELLED: We evaluated EGFR and KRAS mutations between 37 paired primary tumors and corresponding metastases in lung adenocarcinoma. A substantial discordance was found in EGFR mutation status between primary tumors and corresponding metastases including pleural metastases. Moreover, the responsiveness to EGFR tyrosine kinase inhibitors tend to be correlated with EGFR mutation status in metastatic lesions than in primary tumors. INTRODUCTION: The aim of this study was to compare epidermal growth factor receptor (EGFR) and KRAS mutations between primary tumors and corresponding metastases including pleural metastases in lung adenocarcinoma. METHODS: Thirty-seven paired primary lung adenocarcinomas and corresponding metastatic tumors were analyzed for EGFR and KRAS mutations. In addition, 21 pleural metastases including malignant pleural effusion or pleural biopsy were used in performing these mutation analyses. RESULTS: EGFR mutations were detected in 18 primary lung adenocarcinomas (48.6%) and in 16 corresponding metastases (43.2%). EGFR mutations showed a discordance rate of 16.2% (6 of 37 patients) between primary lung adenocarcinomas and corresponding metastases. Among 21 pleural metastases, 3 patients (14.3%) showed that the EGFR mutation was discordant. KRAS mutations were detected in one primary tumor and in two metastatic tumors. Eighteen patients were treated with EGFR tyrosine kinase inhibitors. One of seven patients who experienced partial response had EGFR mutations only in the metastasis, and two of seven patients who experienced progressive disease carried wild-type EGFR only in the metastasis. CONCLUSIONS: EGFR mutations were discordant between primary tumors and corresponding metastases in a significant portion of lung adenocarcinomas. Furthermore, these discordance was also observed in metastases to the pleura, the nearest metastatic site.

Characterization of Monoclonal Antibodies against Human Leukocyte Common Antigen (CD45).

BACKGROUND: The leukocyte common antigen (CD45) is a transmembrane-type protein tyrosine phosphatase that has five isoforms. METHODS: We generated seven murine mAbs against human CD45 by injecting cells from different origins, such as human thymocytes, PBMCs, and leukemic cell lines. By using various immunological methods including flow cytometry, immunohistochemistry, and immunoprecipitation, we evaluated the reactivity of those mAbs to CD45 of thymus as well as tonsil lysates. Furthermore, we transiently transfected COS-7 cells with each of gene constructs that express five human CD45 isoforms respectively, and examined the specificities of the mAbs against the transfected isoforms. RESULTS: In case of thymocytes, lymphocytes, and monocytes, all the seven mAbs demonstrated positive reactivities whereas none was reactive to erythrocytes and platelets. The majority of immune cells in formalin-fixed paraffin-embedded thymus and tonsil tissues displayed strong membranous immunoreactivity, and the main antigen was detected near 220 kDa in all cases. Among the mAbs, four mAbs (AP4, DN11, SHL-1, and P6) recognized a region commonly present in all the five isoforms. One mAb, YG27, recognized four isoforms (ABC, AB, BC, and O). Two mAbs, P1 and P14, recognized the isoforms that contain exon A encoded regions (ABC and AB). CONCLUSION: In this study, we confirmed that AP4, DN11, SHL-1, YG27 and P6, are mAbs reactive with the CD45 antigen whereas P1 and P14 are reactive with the CD45RA antigen.

[A case of Kaposi's sarcoma associated with ulcerative colitis].

Kaposi's sarcoma is a rare and slowly progressive disease that primarily affects the skin but has an associated visceral involvement. It can occur in the HIV-positive patients or patients treated with immunosuppressants. However, it is extremely rare in the patients receiving the treatment for inflammatory bowel disease. We used corticosteroid for the treatment of ulcerative colitis in 60-year-old woman. Then, Kaposi's sarcoma occurred in the skin and colon of the patient. Since she was HIV-negative, we believed that it was developed from the condition of corticosteroid-induced immunosuppression. We present a case of skin and colonic Kaposi's sarcoma in a HIV-negative woman following treatment with corticosteroid for ulcerative colitis.

[A recurred case of a mature ovarian teratoma presenting as a rectal mass].

Mature teratoma is the most common germ cell tumor of the ovary. The tumor is essentially a benign neoplasm and surgical resection of the tumor is the treatment of choice. Recurrence with colorectal involvement after surgical removal of the primary lesion is exceedingly rare and has not been reported in Korea. We present a 43-year-old patient with a rectal mass who had already undergone left oophorectomy due to mature cystic teratoma and right oophorectomy due to hemorrhagic corpus luteum. The rectal mass was composed of a mature teratoma tissue. We postulate that leakage of the tumor elements from the cyst wall led to peritoneal tumor implantation and invasion to the rectal wall.