2. Introduction – Oropharyngeal and Hypopharyngeal Carcinoma

This guideline was prepared as a joint guideline for oropharyngeal and hypopharyngeal carcinoma on the recommendation of the Steering Committee of the Oncology Guideline Program of 01.11.2017 and thus closes the gap between the existing S3 guidelines on squamous cell carcinoma of the larynx and oral cavity.

Over the last 20 years in Germany, it has been possible to enormously improve overall survival as well as long-term functionality for oropharyngeal and hypopharyngeal carcinoma by standardizing the surgical aims to be achieved (e.g. R0 resection with at least 5 mm distance to the tumour margin, further development of large-lumen defect reconstructions), categorizing neck dissection, linking postoperative therapy to clear risk criteria (e.g. extracapsular extension (ECE) of the loco-regional lymph node metastases)[TK1] ), and diversification of radiotherapy techniques and drug-based tumour therapy with standardization of first-line therapy.

Depending on the respective tumour location, spread and biology, we are increasingly seeing differences in the surgical radicality to be selected, in the diversified multimodal overall concept and in the need for early rehabilitation measures in order to optimize overall survival in the context of acceptable late functionality by selecting suitable alternatives. The existing international evidence-based guidelines already contain useful, up-to-date systematic reviews, which are taken into account in this S3 guideline.

This S3 guideline is the final step in completing the S3 LL programme for squamous cell carcinoma of the upper aerodigestive tract in order to achieve a uniform approach with regard to the quality of care and standardization, which is reflected in the quality indicators of the certified centres (head and neck tumour centre according to DKG/Onkozert).

The guideline generally does justice to the interdisciplinary nature of early detection, diagnosis, therapy, rehabilitation and aftercare. The guideline provides reliable support in achieving the therapeutic goals and contributes to reducing the frequency of avoidable complications and improving the prognosis of treated patients. The guideline is intended to provide patients and their relatives with understandable and comprehensible information about the relevant treatment concepts and their effects. The additional patient version of the guideline supports informed, participatory decision-making.

Quality indicators are derived from the guideline, which are particularly helpful for interdisciplinary decision-making in tumour boards, e.g. in head and neck tumour centres (Onkozert), and for mapping the quality of outcomes. Doctors in private practice and general practitioners thus have a recommendation for action in the follow-up care of patients. The guideline also provides valuable information for those involved in functional rehabilitation (e.g. speech therapists) and psychosocial rehabilitation (psychologists, social workers, medical psychotherapists). The guideline leads to an improvement in the communication channels between the specialist groups involved in rehabilitation and the physicians involved in curative treatment and to a better understanding of the underlying disease.

The recommendations in this S3 guideline are aimed at:

• ENT physicians, oral and maxillofacial surgeons, phoniatrists, radiation oncologists, oncologists, pathologists, radiologists, palliative care physicians, radiotherapists, nuclear medicine specialists, virologists, physicians in rehabilitation facilities
• Nursing staff
• Speech therapists
• Psychologists, social workers
• Patient counselling organizations
• Self-help groups
• Cost bearers
• Patients

The guideline is also intended to provide information for general practitioners.

The S3 guideline is valid until the next update. The validity period is set at 5 years from the date of publication (February 2029). Regular updates are planned; if urgent changes are required, these will be published separately. Comments and suggestions for the updating process are expressly welcome and can be addressed to the guideline secretariat:

pharynxkarzinom@leitlinienprogramm-onkologie.de

The methodology of the oncology guideline programme provides for the assignment of recommendation grades by the guideline authors as part of a formal consensus process. Accordingly, a nominal group process or structured consensus conference moderated by the AWMF and DKG was conducted. As part of these processes, the recommendations were formally voted on by the mandate holders with voting rights. The results of the respective votes (consensus strength) are assigned to the recommendations according to the categories in the following table on consensus strength.

For all evidence-based statements (see Chapter 2.2.3) and recommendations, the evidence grading according to GRADE is shown in the guideline, as well as the strength of the recommendation (grade of recommendation) for recommendations. With regard to the strength of the recommendation, this guideline distinguishes between three grades of recommendation (see table: Grading of recommendations), which are also reflected in the wording of the recommendations.

Table: Recommendation grading scheme

Table: Consensus strength

The decision criteria for determining the recommendation grades are explained in the guideline report for this guideline.

Statements/recommendations for which the guideline group decided to work on the basis of expert consensus are indicated as expert consensus. No systematic literature search was carried out for these recommendations (the studies cited in the background texts were selected by the experts involved). For recommendations based on expert consensus, no symbols or letters are used to indicate the strength of the recommendation and the quality of the evidence. The strength of the recommendation is determined solely by the wording used (should/should/can) according to the grading in the table "Scheme of recommendation grading".

In this guideline, only 24% of the recommendations and statements were evidence-based. There are 43 evidence-based recommendations/statements compared to 136 consensus-based recommendations/statements. This low rate is due to the fact that the systematic evaluation of the evidence (PICO) was restricted to clinically important and potentially controversial issues due to limited resources. There is a high level of evidence for many of the recommendations agreed to by expert consensus, which is listed extensively in the background text, including the current state of the research. No additional de novo research of the known data situation was undertaken. These recommendations are uncontroversial and were agreed to in all cases with "strong consensus". Where possible, evidence-based recommendations and statements from the two existing S3 head and neck guidelines [1][2] were adapted/adopted.

All persons involved in the development of the guideline submitted a written declaration of any existing conflicts of interest via the AWMF online platform provided for this purpose at the beginning or at the latest during the guideline process. These were updated again before the first consensus conference.

Prof. Andreas Dietz and the DKG (Dr. med Markus Follmann, Gregor Wenzel) assessed the conflicts of interest of all those involved in guideline development. An overview of the conflicts of interest of the persons involved and the resulting consequences can be found in the guideline report.

Conflicts of interest were dealt with in accordance with AWMF regulations: in order to ensure the greatest possible trustworthiness of the guideline recommendations, care was taken to ensure that the coordinators of the guideline project had only a few thematically relevant conflicts of interest. For this reason, two coordinators (Prof. Andreas Dietz and Prof. Wilfried Budach) were initially appointed, who were flanked by Prof. Georg Maschmeyer for drug-based tumour therapy expertise. The COIs of the two coordinators, which were present only for Chapters 9.2.1 and 9.2.2, were taken into account by their recorded abstention from voting.

Furthermore, it was ensured that members of the guideline group with minor conflicts of interest (e.g. receipt of third-party funding from industry for presentations or authorship) were not allowed to take on a leadership role, such as sole chairmanship of a working group or main responsibility for the preparation of evidence on a research question. A leadership role may be assumed if a second person is also involved in leading the working group without any conflict of interest.

Members of the guideline group with moderate conflicts of interest (advisory board or consultant activities and receipt of third-party funding from industry in a responsible position) may only participate in consensus building as advisory, non-voting experts.

Persons with high conflicts of interest (ownership interest) were not allowed to participate in the deliberations of the guideline group, but could contribute their knowledge in the form of written comments if they wished.

The external, independent moderation of the formal consensus-building process as well as the interdisciplinary development of the guideline and its public/expert review in the consultation phase are further aspects that are intended to reduce undesirable influence from conflicts of interest and strengthen confidence in the recommendations made.