Radiological monitoring of the treatment of solid tumors in practice.

PURPOSE: Thanks to advances in cancer therapy, the diagnosis of "incurable cancer" is increasingly able to be changed to a chronic disease that is manageable over long periods, resulting in a change in the clinical management of cancer patients with solid tumors. New parameters are needed to measure the success of targeted therapy in clinical trials. MATERIALS AND METHODS: Review article on the basis of selective literature research. RESULTS: In order to assess how well solid tumors respond to treatment, size-based criteria called RECIST (Response Evaluation Criteria in Solid tumors) have been defined. These criteria have been validated in large oncology trials and are currently used most frequently. New molecular therapies often do not - or at least do not immediately - reduce the size of a tumor. Therefore, RECIST evaluation should be critically assessed especially in the case of modern therapies. Any additional available tumor biology information should be considered. In radiology new methods and developments of RECIST have been introduced to better assess the success of targeted therapy. CONCLUSION: Assessment according to RECIST has been proven for the follow-up of classic tumor therapy. For the monitoring of targeted therapies, new parameters are often required. Therefore, some specific tumor- and therapy-adapted criteria have already been defined to better evaluate treatment success in clinical trials.

[Response criteria for malignant lymphoma]. / Verlaufsbeurteilung des malignen Lymphoms.

CLINICAL/METHODICAL ISSUE: A proven criterion for assessing tumor response is the increase in tumor size. Unlike most tumors, lymph nodes are normal anatomical structures and can be measured even when benign. The International Working Group (IWG) criteria for lymphomas therefore combine morphological with functional (positron emission tomography PET) and biopsy (bone marrow biopsy) parameters. The IWG criteria have been established as the standard in clinical trials and take nodal involvement, spleen, liver involvement as well as bone marrow involvement into account, which makes the response evaluation complex. STANDARD RADIOLOGICAL METHODS: This involves an investigator-dependent, non-standardized and poorly reproducible estimation of tumor response to therapy. METHODICAL INNOVATIONS: The formulation of standardized response categories for malignant lymphomas. PERFORMANCE: The aim was to produce uniform and standardized criteria for application in medication studies. ACHIEVEMENTS: Established as the standard for medication studies but too time-consuming for practical application. PRACTICAL RECOMMENDATIONS: An improved practicability can be achieved by incorporating a computer-assisted evaluation program.

[Cellular mechanisms of tumor response: clinical demands]. / Zelluläre Mechanismen der Tumorresponse : Klinische Anforderungen.

Diseases caused by cancer have become more common due to an increase in life-expectation, but the probability of reaching an old age with or without a tumor disease is still increasing. According to the statistics of the German Cancer register, at present more than half of cancer patients survive for at least 5 years after cancer has been diagnosed. Many tumors can be cured using innovative neoadjuvant and adjuvant therapy regimes, but the options for palliative therapy have also been improved. This leads to an increasing importance of the evaluation of the tumor response using imaging techniques. Classically, tumor response is measured by imaging using the RECIST (response evaluation criteria in solid tumors) criteria, which define the changes in size of the tumor during therapy. However, there is increasingly more evidence that RECIST as the only measure of tumor response, does not document tumor response for all tumor entities and especially not for many medications known as targeted therapy. This article gives a review of the principles and mode of effect of various therapy regimes as well as the clinical demands on imaging techniques.