Biological agents – hope and caution

Having actively participated in the field of growth factor research since the early days of growth factor discovery ^1,2 I can comment with great delight and amazement on the progress made since those early days. Not only our basic knowledge has expanded exponentially, but growth factors, their receptors and complicated signaling systems became legitimate targets of sometimes quite effective chemotherapy. This issue brings a variety of interesting papers dealing with various aspects of tumor therapy, ranging from traditional combination protocols for management of cholangiocarcinoma ³ to novel hypofractionated stereotactic radiation therapy of pituitary adenomas ⁴ to several papers which critically appraise the state of the art of cancer treatment with several recently introduced biological agents. ^5-8