Cyclooxygenase-2 expression is associated with well-differentiated and intestinal-type pathways in gastric carcinogenesis.

BACKGROUND/AIMS: Cyclooxygenase-2 (COX-2) expression appears to be increased in several different types of human cancers, suggesting that the presence of COX-2 is associated with carcinogenesis. Recently, increased expression of COX-2 has been frequently detected in gastric cancer, and this may have prognostic significance. In the present study, we aimed to analyze the expression of COX-2 in a much larger sample to determine whether COX-2 expression is related to the clinicopathological features and survival rates of patients with gastric cancer. METHODS: We investigated 140 patients with gastric cancer who underwent surgery between January 1992 and December 1993 and examined the expression of COX-2 in human gastric cancer tissue by immunohistochemistry. RESULTS: COX-2 expression was present in the cytoplasm of tumor cells but not in normal gastric epithelia. Positive expression of COX-2 was detected in 86 of 140 gastric cancers analyzed (61.4%). Positive expression of COX-2 correlated with the depth of tumor invasion (p = 0.015). However, there was no association between COX-2 expression and tumor stage or status of lymph node or distant metastasis. Furthermore, COX-2 expression was not associated with patient survival (p = 0.816). Positive expression of COX-2 occurred more frequently in intestinal than in diffuse or mixed types of cancer and correlated with tumor differentiation (p < 0.001, p = 0.001, respectively). CONCLUSION: These results suggest that COX-2 may play an important role in the evolution of gastric carcinogenesis and be associated with well-differentiated and intestinal type pathways in gastric carcinogenesis. However, COX-2 expression seems to be less useful for establishing prognosis for gastric cancer.

A Case of AML Atypical M2 with Granulocytic Sarcoma in the Meninges Induced Remission by All-Trans Retinoic Acid and Combined Chemotherapy / 대한혈액학회지

We repoarted a rare case of AML atypical M2 who developed granulocytic granulocyte sarcoma in the meninges which was induced complete remission with all-trans retinoic acid (ATRA), daunorubicin and cytosine arabinoside (Ara-C). Morphological and immunophenotypic study of leukemic cells in this patient suggested acute promyelocytic leukemia. However, leukemic clees lacked both t (15;17) and PML-RARalpha gene rearragement, rather showed t (8;21). The patient was diagnosed as AML atypical M2.