The aim of personalized medicine is to offer a tailor-made therapy. Side effects could be avoided so that the patient derives optimal benefit from a therapy. Medical resources should thus be optimally deployed and potential side effects avoided. However, more is now expected of PM. PM should allow not only determination of the response to therapy but also estimation of the disease recurrence risk. Against the background of the future financial viability of the healthcare system and the innovation this will require, PM arouses great interest in all involved in the healthcare system. PM has the potential to improve the quality of medical care for individual patients, and at the same time to improve the efficiency and affordability of the healthcare system. Thus PM offers new opportunities for patients, physicians, insurance companies, politicians and industry. Despite the highly promising approaches, PM is finding its way only slowly into everyday clinical practice and healthcare.
The relevance of PM in early detection was examined in the case of four common cancers (colorectal cancer, lung cancer, breast cancer and prostate cancer). Our results show that the methods of PM play a decisive role especially in screening.
This article shows possible ways of using PM in screening. As these merely provide food for thought and are not detailed concepts, the potential uses proposed here certainly leave room for critical enquiry. Questions remaining include validity of biomarker use in screening, practical and financial applicability of mass screening, cut-offs of low- and high-risk groups, and patient profitability through application of these methods.
The pitfalls in measuring biomarkers must also be pointed out and standardized sample treatment must be ensured so that comparable results are obtained. Moreover, the half-lives of most markers have not yet been defined precisely. The problem of specificity or allocation of biomarkers to their respective malignant diseases was alluded to above. The list of unanswered questions on the topic of PM in the context of screening is certainly a long one. Nevertheless, PM in the area of screening is promising and to date has been used too little.
In summary, it should be emphasized that numerous promising biomarkers are already known in malignant diseases. This results in several possibilities for individualizing and revolutionizing screening.
Personal view and outlook
Despite numerous unanswered questions regarding the feasibility and use of biomarkers, we regard their use in screening for malignant diseases as the medicine of the future. Use of biomarkers can improve the early detection of malignant disease decisively. Even though the examples mentioned here, such as the breath test, are still immature ideas that leave much room for criticism, these examples indicate future possibilities in medicine.
In future, biomarkers will play a crucial role not only on the treatment level but also on the diagnostic level. Target-specific therapy will therefore be preceded by a biomarker-oriented screening programme. PM thus consists of individual screening and target-specific therapy.