>> MTK have existed since the 1970s (Kleeberg 2018). The importance of MTK in the care of people with cancer is reflected today both in the National Cancer Plan (BMG 2017) and in the National Decade against Cancer (Strategy Group of the National Decade against Cancer 2019). MTK are also anchored in treatment guidelines such as the breast cancer disease management program and the guidelines of the European Society of Medical Oncology (ESMO). An MTK offer from the facilities is also mandatory for the certification of oncological treatment centers by the German Cancer Society (DKG) and the competence centers for drug tumor therapy by the German Society for Hematology and Medical Oncology (DGHO). For certification, specific requirements are formulated for MTK, which include in particular structural features such as the participation of certain professions, for example from surgery, radiology, pathology, radiation therapy and internal oncology. In the DKG's requirements for the certification of organ cancer centers, for example, the requirements for tumor conferences are formulated under “1.2 Interdisciplinary cooperation”. For colorectal cancer centers this means, among other things: “A tumor conference must take place at least once a week. Participation at the conference at specialist level is mandatory for the following disciplines: visceral surgery, gastroenterology, radiation therapy, hematology/oncology, pathology, radiology.” Furthermore: “All cases should be presented pretherapeutically/postoperatively [...]. If no introduction is made, this must be comprehensibly justified in the patient file” (DKG 2020). The implementation is checked in the audits and is taken into account as a key figure in the annual reports. Through these certifications, MTK is well established for common solid tumor entities such as colon or breast cancer, but also for some rarer entities such as liver cancer. There are currently 1,525 centers certified by the DKG (DKG 2021). The documents from the DKG certification process represent the largest source of data on MTK in Germany. The certification of the competence centers for drug tumor therapy by the DGHO will only begin in 2021. However, there is no data on quality, process flows or variances that go beyond the requirements associated with certification.
In addition, various forms of MTK, hema boards and other multidisciplinary meetings for the care of hematological and oncological patients also take place in non-certified hospitals or networks of outpatient specialist groups. However, there is neither information on the number nor on structural or procedural characteristics. A good three quarters of practicing hematology and oncology specialists take part in internal tumor boards and 94% take part in external tumor boards (Hermes-Moll et al. 2016). The number of participants in the external MTK varies between 2 and 30 people (mean 13, standard deviation 5.5). The number of cases discussed also indicates a large variance between the MTKs with a range of 1-30 (mean 12, standard deviation 5.9) (Hermes-Moll et al. 2016).
Given the lack of a legal definition of MTK, neither data from official statistics nor documentation from self-governing bodies (e.g. associations of statutory health insurance physicians) provide any useful information. In the various remuneration systems of healthcare providers, the discussion of a case in MTK is not reflected, with the exception of outpatient specialist medical care (ASV). An analysis of MTK is also not possible with the data from clinical cancer registries and hospital quality reports. This means that so far it is difficult to make any statements about MTK for Germany. Existing studies on MTK are primarily facility- or hospital-related. However, evidence from the medical profession (Hermes-Moll et al. 2016; personal communication) suggests strong heterogeneity in MTK.
In principle, MTK can be differentiated in terms of, among other things, the time at which it is included in the treatment process, the focus set, the participant structure and the place where it is carried out. The respective structural, personnel and regional conditions play a key role.
Some distinguishing features are outlined as examples in Figure 1.
Along with medical advances, MTKs are also subject to change. The increasing influence of molecular diagnostic findings on treatment options in hematology and oncology is also reflected in the names of the MTK. In addition to the well-known MTK, "molecular tumor conferences" are increasingly being introduced in oncological facilities, in which molecular-genetic analyzes of the tumor tissue or blood play a major role in determining the recommendations (Rolfo et al. 2018; van der Velden 2017; DGP 2017). These are often cases in which standard examinations and treatment options have already been exhausted. In addition, the group of participants in the MTK may be expanded to include people from human genetics and bioinformatics who were not previously included (Merry et al. 2018). However, molecular-genetic diagnostics have also become part of the treatment decision in MTK that are not explicitly described as "molecular", e.g. in the case of lung cancer. In addition, there are efforts to establish so-called "translational" MTK in order to promote knowledge-generating care in oncology (DGHO 2018). It is not known to what extent this form of translation has already found its way into healthcare practice within the context of MTK.
Internal process flows in MTK
MTK are therefore collective forms of medical action in care, the results of which may be influenced by the personal, organizational and cultural conditions under which they take place. The MTK participants may have different assessments regarding how to proceed with therapy (Homayounfar et al. 2014). Value judgments and other non-medical factors can also influence MTK recommendations (Schildmann et al. 2014). Although the majority of MTKs take place in inpatient care facilities, the majority of practicing physicians in hematology and oncology regularly take part in MTKs in hospitals (Hermes-Moll et al. 2016). The resident specialists are therefore external participants of MTK. The common goal of providing the best possible care for cancer patients and regular collaboration in MTK can improve cooperation between resident and inpatient specialists. However, tensions have also been reported in the past between the various professional groups in the outpatient and inpatient sectors and between internal and external MTK participants (Devitt et al. 2010; Parikh 2019), which can also (unconsciously) impact decision-making processes (Devitt et al. 2010). It cannot be denied that MTK decisions can have a major influence on regional patient flows and their allocation to treatment facilities. This in turn can have an impact on the care situation and quality of tumor patients.
The expansion of the forms of MTK and the inclusion of additional specialist groups can ultimately also have an impact on the dynamics within the MTK. With increasing complexity, it must increasingly be assumed that the respective knowledge of an individual MTK participant will be exceeded and mutual trust will become a central element (Haier 2016; Merry et al. 2018). The increasing need for knowledge, e.g. B. for special cases or “orphan diagnoses”, may require the involvement of specialists across the region. Not least because of the importance of communication processes in MTK, demands have been formulated for standardization of the structures and processes of MTK (Homayounfar et al. 2015; Lamb et al. 2012) as well as regular evaluations of MTK (Rosell et al. 2018). Recommendations for action and analyzes for decision-making within the MTK come primarily from the Anglo-Saxon region. But here too, there is a lack of prospective studies assessing the functional organization and implementation of MTK (Specchia et al. 2020). Institutional and, above all, cross-sectoral analyzes are missing for Germany.
Result and implementation of the MTK recommendation
A central aspect in the implementation of therapy recommendations based on MTK decisions (“tumor board adherence”) is the sometimes lack of consideration of the patient's wishes (Baes et al. 2020; Basta et al. 2017; Gruber 2012; Hollunder et al. 2018). This can be achieved, for example, by involving nursing staff (Knötgen 2020; Rosell et al. 2018) or the participation of patients in MTK (Diekmann et al. 2020; Heuser et al. 2019; Bate et al. 2019; Hahlweg et al. 2015) can be achieved. The latter, in turn, is only implemented in individual centers and is evaluated differently by the medical profession (Heuser et al. 2020).
Another aspect is the communication of the MTK recommendation by the doctors to those affected. According to a survey in oncology practices, less than half of cancer patients knew whether their case was discussed in an MTK (Hermes-Moll et al. 2016). Central aspects are also the type of communication of the MTK recommendation to those affected and the integration of the MTK recommendation into a joint decision-making process regarding the therapeutic approach (shared decision making).
Effort and costs of MTK
Preparing and participating in MTK requires a certain amount of time. A Prognos report puts the additional costs incurred by MTK at around 1.4 million euros per year for a prototypical top-level oncology center (CCC) and at 370,000 euros per year for a prototypical organ cancer center (CC) (Holterhöff/Klein 2017). The additional effort for practices connected to the network is not taken into account. On average, specialized oncology practices are each connected to 3.3 centers (Baumann/Schmitz 2016). There are currently no figures available for other specialist groups in outpatient care. These significant additional costs for the centers and network partners are generally not reimbursed. Only within the framework of the ASV is the presentation of a case in an MTK by a member of the core team remunerated (KBV 2019). The billing of the EBM number for the other participants in the MTK, e.g. B. from radiation oncology is not planned. International studies show that MTKs are sometimes perceived as inefficient (Bunnell et al. 2010). Concerns about effort and organization were also documented on the part of residents (Abenhardt 2012; Hermes-Moll et al. 2016).
Conclusion
In summary, it can be said that multidisciplinary case discussion is an integral and important part of the qualified care of cancer patients, but there are still significant research gaps that cover basic structural characteristics, selection and access of patients, procedural aspects such as communication and decision-making, but also the further implementation of the MTK recommendation and the cost-benefit analysis. The resulting questions are part of other tasks and topic areas of health services research in oncology (Kowalski et al. 2020). The DKG's requirements for MTK for certification provide an important framework for the quality of MTK in Germany. However, there are also other forms of MTK outside the certified centers as well as differences in the implementation of MTK that go beyond the certification requirements, which have not yet been systematically identified and nothing is known about their effects on medical providers and patients. It can be assumed that there are regional peculiarities that lead to a nationwide inconsistent picture of care through MTK, for example due to the influence of population density and associated care structures, the presence of larger oncology centers that influence patient flows in a region, or even through local projects or initiatives. In view of the impact on the further care of patients and the large amount of time and personnel required by MTK, the most efficient and effective cooperation in MTK is of great importance for the organizers and participants of MTK. The difficulty will often lie in overcoming discrepancies between the requirements on the one hand and the practical feasibility on the other (Haier 2016).
The Central Institute for Statutory Health Insurance in the Federal Republic of Germany (Zi) is currently funding a project by the Scientific Institute of Resident Hematologists and Oncologists (WINHO), which aims to investigate the structures, variances and processes of MTK (also outside of certified centers). . This can cover part of the existing research needs regarding MTK. Further cross-institutional and cross-sector studies that take into account the special structures of the German healthcare system are necessary in order to cover the diverse research areas surrounding MTK. <<