Reference Equations for the Six-Minute Walk Distance in Healthy Korean Adults, Aged 22-59 Years / 결핵및호흡기질환

BACKGROUND: The six-minute walk test has been widely used in people with chronic cardiopulmonary disorders as an outcome assessment with regards to therapeutic or prognostic determinants. This study was undertaken to determine the six-minute walk distance (6MWD) in a sample of healthy Koreans and to create a reference equation. We also compared the 6MWD of our cohort with previously published equations. METHODS: Two hundred fifty-nine healthy subjects (95 males) aged 22-59 years performed two walking tests using a standardized protocol. 6MWD was defined as the greatest distance achieved from the two tests. The effect of anthropometrics on the 6MWD was also investigated. RESULTS: The average 6MWD was 598.5+/-57.92 m, with significantly longer distances by males (628.9+/-59.51 m) than females (580.9+/-47.80 m) (p<0.001). Age, height, weight, and body mass index were significantly correlated with 6MWD in univariate analysis. Stepwise multiple regression showed height to be single independent predictor of 6MWD (r2=0.205, p<0.001). The reference equations derived in Caucasian and North African populations tend to overestimate the distance walked by Korean subjects, while Asian equations underestimate it. CONCLUSION: The average 6MWD in these Korean populations was 600 m. The regression equation revealed that individual's height was the most significant predictor of distance, explaining 20.5% of the distance variance.

Synchronous, Orthotopic Occurrence of Early Gastric Cancer with Gastrointestinal Stromal Tumor that Mimicked Advanced Gastric Cancer

In recent years, the synchronous occurrence of two adjacent but histologically distinct tumors arising in the same organ has been reported. The simultaneous development of gastric adenocarcinoma and gastrointestinal stromal tumor (GIST) is very uncommon. The question raised was whether such a coexistence is a simple incidental finding or whether the two neighboring tumors are caused by a same unknown carcinogenic agent. Many doctors may have an interest in this rare condition and we expect further studies will be done in order to determine if there is any association between the two different tumors. We report a unique case of a synchronous, orthotopic occurrence of an early gastric cancer with GIST in the same location that mimicked advanced gastric cancer.