title: Lymphocyte responses following open and minimally invasive thoracic surgery.
abstract: BACKGROUND
  Immunosuppression associated with surgery may predispose to increased tumour growth or recurrence. Lymphocytes are central components of the immune network, signalling specific and non-specific responses in tumour immunosurveillance. This study was therefore designed to compare the effects of minimally invasive and conventional approaches to major thoracic surgery on lymphocyte populations and oxidative activity.
  
  
  METHODS
  The effects of conventional and minimally invasive video-assisted thoracic surgery (VATS) on the numbers and types of circulating lymphocytes and on lymphocyte oxidation were compared in a prospective randomized study of 41 patients undergoing lobectomy for peripheral bronchogenic carcinoma. Blood taken pre-operatively and on days 2 and 7 post-operatively was analysed for T (CD4, CD8), B (CD19) and natural killer (NK) (CD56, CD16) cell counts and for lymphocyte oxidative activity. Leucocyte numbers were compared with pre-surgical values and oxidative rate with healthy donor controls.
  
  
  RESULTS
  Lymphocyte counts fell after surgery; VATS was associated with less effect on circulating T (CD4) cells at 2 days and on NK lymphocytes at 7 days post-surgery. Lymphocyte oxidation was less suppressed in the VATS group 2 days after surgery. In general, post-surgical changes in key cells of cellular immunity were smaller in the VATS group, and recovery to normal levels was more rapid.
  
  
  CONCLUSIONS
  The degree of invasiveness of thoracic surgery may influence the extent of immunosuppression in patients undergoing pulmonary lobectomy for pulmonary neoplasm.
authors.affiliation: Royal Infirmary of Edinburgh; University of Edinburgh, Edinburgh, UK.
authors.forename: H A
authors.initials: HA
authors.lastname: Leaver
authors.forename: S R
authors.initials: SR
authors.lastname: Craig
authors.forename: P L
authors.initials: PL
authors.lastname: Yap
authors.forename: W S
authors.initials: WS
authors.lastname: Walker
mesh_terms: D000368:Aged; D002283:Carcinoma, Bronchogenic / Q000601:surgery; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007111:Immunity, Cellular / Q000502:physiology*; D018655:Lymphocyte Count; D008214:Lymphocytes / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures; D018384:Oxidative Stress / Q000502:physiology*; D011013:Pneumonectomy; D011446:Prospective Studies; D018709:Statistics, Nonparametric; D019616:Thoracic Surgical Procedures