1. Editor's preface

   EditorialNotes Pages: 321 - 321

2. Natural killer cells: Artifact to reality:

   • Robert K. Oldham

   OriginalPaper Pages: 323 - 336

3. Natural killer cells in human solid tumors

   • Martino Introna
   • Alberto Mantovani

   OriginalPaper Pages: 337 - 350

4. The detection and evaluation of human tumor metastases

   • D. J. R. Laurence
   • A. M. Neville

   OriginalPaper Pages: 351 - 374

5. On a possible epigenetic mechanism(s) of tumor cell heterogeneity

   • Philip Frost
   • Robert S. Kerbel

   OriginalPaper Pages: 375 - 378