Specialist healthcare group BTG expects full-year sales to be at the top end of the guidance after a 'transformational year'.Revenues for the financial year to March 31st are expected to be at the upper end of the £275-285m guidance range, which the company had reiterated as recently as January. This is up from £234m the year before.The firm highlighted a strong performance in the Interventional Medicine business, due to the continued expansion of the embolisation and drug-eluting bead products - known as 'the Beads' - and new sales contributions from the acquisitions of TheraSphere and EKOS Corporation in July 2013.Licensing revenues were higher as a result of increased worldwide use of Johnson & Johnson's prostate cancer drug Zytiga. This helped to offset lower growth in the Specialty Pharmaceuticals business after the maturity of the antidote portfolio.Chief Executive Louise Makin said BTG has made "tremendous progress during a truly transformational year"."The acquisitions and the approval of Varithena make us a leader in interventional medicine with four differentiated, growing products. We will continue the US roll-out of Varithena and the activities to support expansion of the Beads, TheraSphere and EKOS into new indications and additional geographical markets, confident that we are well positioned to deliver sustainable, profitable growth."The stock was 4.2% higher at 563.94p in early trading on Thursday.BC