Shares of Boston Scientific Corp. BSX, -0.44% dropped 6.3% in premarket trading Tuesday, after the medical technology company provided a fourth-quarter sales outlook that was below expectations. On a preliminary basis, sales rose 13.4% to $2.90 billion, below the FactSet consensus of $2.93 billion, as MedSurg revenue rose 9.8%, Rhythm and Neuro grew 3.5%, Cardiovascular increased 18.7% and medical devices rose 11.2%. The company said it is still closing its books for the quarter, but estimates it will report adjusted earnings per share within its previously issued guidance range of 42 cents to 45 cents; the FactSet consensus was 44 cents. The stock has run up 19.8% over the past three months through Monday, while the SPDR Health Care Select Sector ETF XLV, -0.35% has rallied 14.0% and the S&P 500 SPX, +0.70% has gained 10.9%.