A tissue removing catheter includes an apposition mechanism that selectively imparts an axially compressive load on the catheter body to bend the catheter and urge a tissue-removing element toward a blood vessel wall. The apposition mechanism can include one or more adjustment lines and an adjustment mechanism for selectively tensioning one of the adjustment lines to impart the compressive load on the catheter body. Two adjustment lines can have diametrically opposed positions and be wound onto a spool of the adjustment mechanism in opposite directions so that rotation of the spool simultaneously shortens one adjustment line and lengthens the other. The catheter body can have a more flexible bending segment adjacent the tissue-removing element to promote bending near the tissue-removing element operative to urge the tissue-removing element in apposition with the blood vessel.