title: Potential of limited day 21 post-chemotherapy CT scan in predicting need for post-chemotherapy surgery in nonseminomatous testicular germ cell cancer.
abstract: Nonseminomatous germ cell cancers (NSGCC) have a varied response to chemotherapy, some melting away with resultant cure, some have tumour stem cell necrosis and residual benign disease whilst others are resistant to treatment. The latter two require surgical excision in order to identify those needing high intensity chemotherapy.
  
  
  OBJECTIVE
  The aim of this study was to investigate whether it was possible to give an earlier prediction of need for surgery after chemotherapy on the basis of a limited CT scan performed after the first course.
  
  
  METHODS
  Twenty-three patients with metastatic NSGCC undergoing induction chemotherapy were studied. The site of the maximum disease was noted before treatment and only this area was rescanned at day 21. The change in disease bulk, measured as maximum transverse diameter (MTD), was compared with appearances on a CT scan immediately after chemotherapy and post-treatment response.
  
  
  RESULTS
  Of those patients showing a poor response on the day 21 scan (i.e. no change, or less than 50% reduction in MTD), 70% required early surgical excision of residual disease, while none of the good responders (i.e. greater than 50% reduction in MTD), required immediate surgery (p < 0.001).
  
  
  CONCLUSIONS
  It is concluded that a limited day 21 CT scan may represent an independent predictor of good and poor response to chemotherapy, thus enabling reduction in chemotherapy and its toxicity in good responders and early identification of those who may need surgical excision, thereby permitting easier scheduling of these often difficult surgical procedures.
authors.affiliation: Department of Medical Imaging, The Royal Hospitals NHS Trust, The Royal London Hospital, London, UK.
authors.forename: D
authors.initials: D
authors.lastname: Tsetis
authors.forename: A
authors.initials: A
authors.lastname: Sharma
authors.forename: M
authors.initials: M
authors.lastname: Easty
authors.forename: I
authors.initials: I
authors.lastname: Brown
authors.forename: T
authors.initials: T
authors.lastname: Oliver
authors.forename: O
authors.initials: O
authors.lastname: Chan
mesh_terms: D000328:Adult; D003131:Combined Modality Therapy; D006801:Humans; D008297:Male; D009362:Neoplasm Metastasis / Q000000981:diagnostic imaging / Q000473:pathology; D009373:Neoplasms, Germ Cell and Embryonal / Q000000981:diagnostic imaging* / Q000473:pathology / Q000628:therapy; D011237:Predictive Value of Tests; D011446:Prospective Studies; D013736:Testicular Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000628:therapy; D014057:Tomography, X-Ray Computed