Hospital owner Spire Healthcare Group said it had traded in line with expectations in the first quarter and reiterated its annual guidance.In the three months to 31 March, the FTSE 250 group reported a 10% growth in revenue year-on-year, boosted by strong performances in all of its three divisions, particularly in the self-pay and national health services divisions."While the growth in the NHS business in the period has been strong, it is also gratifying that there has been continued strong growth in the self-pay business," said group chief executive Rob Roger.Spire said that excluding its acquisition of St Anthony's Hospital last May revenue rose 6%, adding its development projects remained on schedule, with a new six-operating-theatre block at St Anthony's set to be completed by July 2016.Meanwhile, construction of a new cancer radiotherapy centre in Chelmsford, Essex, is expected to be ultimate within the year and work on the site for two proposed hospitals in Manchester and Nottingham had got underway.Spire shares were up 0.20% to 350.10p at 09:25 on Tuesday.