Recent randomized trials have questioned the need for systematic use of whole breast irradiation after lumpectomy in the context of selection by age, tumor size, or tamoxifen treatment . While the data in PBI consolidate and mature, there is solid evidence to support moderation in clinical practice modification. Professor Bartelink  has summarized arguments to question the potential contribution of PBI, in particular IORT, to change clínical practice in the treatment of early breast cancer. The most relevant issues to be addressed, for an sceptical or conservative opinion regarding PBI, are as follows:
The omission of external beam irradiation without validated tools for selection of patients according to biological risk might compromise local control and survival.
The biological effects (both in tumor control and normal tissue toxicity) of a high single radiation dose, as is used in IORT, or altered fractionation as is used in other PBI techniques trials are speculative, with a significant risk for unpredictable late damage to normal tissue.
Target volume definition and dosimetric characteristics of the two ongoing randomized clinical trials have major methodological and technical differences, which will make local results uncomparable.
Some additional topics will be introduced for discussion in the presentation, such as influence of PBI in the radiotherapy management of metastatic axia, modification of scales for cosmetic assessment, treatment planning availability, dosimetric disturbances with the use of shielding material, and opportunities for prospective testing of biological predictive factors on tolerance of normal tissues.
The mentioned arguments seem valid and should be influential in the scientific development of PBI for breast cancer. Experts in PBI and precision radiotherapy for human cancer have been particularly meticulous in analyzing local effects and topography of recurrences. If PBI successfully contributes to the treatment of breast cancer, then surgeons and radiation oncologists should be open minded and change their clinical practice. Health authorities should facilitate the appropiate technology to ensure that this particular population breast cancer patients receives quality treatment.