Abstract
The field of thyroidology has benefited tremendously from publication of a number of evidence-based guidelines recently promulgated by professional organizations such as the American Thyroid Association, The Endocrine Society, and the American Association of Clinical Endocrinologists. Though many of these guidelines offer specific commentary about surgical management of thyroid disease, they focus primarily on medical aspects of thyroid care. The publication of The American Association of Endocrine Surgeons (AAES) Guidelines for the Definitive Surgical Management of Thyroid Disease in Adults (1) and its accompanying executive summary by Patel et al. (2) are the first documents of their kind to specifically and substantively focus on surgical management of thyroid diseases and are, therefore, most welcome additions to the growing list of guidance documents already in wide use within our field.
The authors are primarily surgeons but include a medical endocrinologist and a pathologist. Without exception, these contributors are all internationally recognized experts in thyroidology and their collaboration represents an impressive alignment of experience, talent, and academic achievement that lends considerable heft to this guideline.
The guideline includes an initial focused summary and review of thyroid disease epidemiology and pathogenesis that provides context for the clinical practice recommendations that follow. These recommendations utilize the now common approach to data review and evidence grading developed by the American College of Physicians (3). This process occurs in multiple stages that begin with systematic review of relevant published data, critical evaluation of the evidence by an expert committee, and the final development of summary statements with graded reference to both the strength of the recommendation and the quality of the foundational evidence. The bibliographies of documents generated through this intensive process of critical evidence analysis are highly curated summaries of the most relevant and informative literature pertinent to the questions under review. As a reference source, such bibliographies are valuable in their own right. Similarly, recommendations developed with this process and focused through the discerning lens of an expert panel are also typically authoritative and invaluable. This publication is no exception.
The American Association of Endocrine Surgeons Guidelines for the Definitive Surgical Management of Thyroid Disease in Adults contains a total of 66 evidence-based recommendations composed of 72 discrete guidance statements. The committee designated 94% of the recommendations as “strong” however, only 8 (11%) of the 72 statements are supported by high-quality evidence such as randomized, blinded, and controlled trials. Of an additional 60 guidance statements, approximately half are based on moderate-quality evidence and half on low-quality evidence, and a remaining 8% are either weak recommendations or in a single case a strong recommendation based on insufficient evidence. Does the relative lack of high-quality evidence diminish the value of this work? We do not think so. Though clearly high-quality evidence is preferable to support clinical decision making, its relative paucity is emblematic of the reality of practice in our field. Like it or not, we as clinicians and the expert members of this group of authors must wrangle these often sprawling and inchoate data and make decisions about how to take care of actual patients. What the document reflects is that many practical aspects of thyroid care for which there is near universal consensus are frequently based on very limited empiric evidence. Consider the following “strong” recommendations for which there is likely nearly complete professional agreement, all of which are perhaps surprisingly based on low-quality evidence: Recommendation 7b: FNAB of a sonographically suspicious cervical LN should be performed when the results will alter the treatment plan. (Strong recommendation, low-quality evidence) Recommendation 26: The recurrent laryngeal nerve should be identified to help preserve it. (Strong recommendation, low-quality evidence) Recommendation 61: Patients with significant post-thyroidectomy hypocalcemia should receive oral calcium as first-line therapy, calcitriol as necessary, and intravenous calcium in severe or refractory situations. (Strong recommendation, low-quality evidence)
As a tool to guide us where definitive data all too often do not exist—but where we must nonetheless make sound decisions—the consensus recommendations from this expert panel are in fact invaluable. Precisely because the document succeeds in providing cogent and well-reasoned recommendations based on data as they exist in the real world, we see The American Association of Endocrine Surgeons Guidelines for the Definitive Surgical Management of Thyroid Disease in Adults as particularly important. It serves as a roadmap to guide us as close as possible to the idealized goal of perfect clinical practice in a world of clearly imperfect data.
The topics covered in The American Association of Endocrine Surgeons Guidelines for the Definitive Surgical Management of Thyroid Disease in Adults are wide ranging. Many bread and butter topics germane to surgical management of thyroid disease such as the extent and indications for thyroid surgery, pre- and postoperative care, and technical issues related to the surgical technique are not surprisingly covered with clear, thoughtful, and concise discussion. Discussion of more controversial topics is also included. A selected list includes: The use of presurgical imaging to guide the extent of thyroid surgery. The absence of benefit associated with the use of perioperative antibiotic prophylaxis in standard transcervical thyroid surgery. Techniques to achieve optimal incision placement, exposure, and hemostasis as well as guidelines that address both initial and reoperative surgical management. The utility of intraoperative recurrent laryngeal nerve monitoring as well as medical and surgical management of recurrent laryngeal nerve injury. Remote access approaches for thyroid surgery. Active surveillance for small intrathyroidal cancers. Whether and to what degree molecular diagnostic testing should guide surgical management. Recognition that gastric bypass patients are at increased risk for severe postoperative hypocalcemia after thyroidectomy. Standards of interdisciplinary communication among involved health care providers to improve patient safety.
Though quite comprehensive, the document does not intend to be encyclopedic and is highly focused on surgical issues in thyroidology. But by doing so, the authors fill an important void that has until now existed in the literature. There is undoubtedly much that even an experienced thyroid surgeon can learn from this publication, but it is perhaps those surgeons who have more limited experience with thyroid surgery that may benefit most. Over 80% of thyroidectomies in the United States are still performed by surgeons who do 25 or fewer thyroidectomies per year (4). This comprehensive review of many key topics in surgical management of thyroid disease, the informed discussion and evaluation of the data by this expert and accomplished group of thyroid clinicians, and the on-target and pertinent recommendations is likely to benefit this group especially.
Can this document be improved? Well, as a first ever a guideline statement for surgical management of thyroid disease, it is already comprehensive and outstanding. But, as the title suggests, it only addresses surgical care of adult patients. A comprehensive expansion that covers surgical issues specific to the pediatric population—with its own unique challenges—would be a welcome and useful addition.
All but 4 (6%) of 72 discrete recommendations in this document are “strong” despite the fact that only 8% are founded on high quality data. This is, in part, due to the somewhat less stringent criteria for evidence grading formulated in the American College of Physicians' (ACP) 2010 guideline rubric, which was used in this document (5). The more rigorous requirements presented in the 2019 update from ACP will likely force subsequent updates to adopt a more nuanced distribution of the recommendations along the spectrum from “strong” to “conditional” based on the quality of the evidence. This will perhaps prompt further and informative discussion about why some recommendations might remain “strong” even when data to support such conclusions are lacking, and perhaps make useful distinction between strong recommendations based on compelling data in contrast to those based on expert opinion.
Along these same lines, the relative lack of high-quality data that are inarguably fundamental for the best clinical decision making raises the question of what studies might further contribute to the evidence-based recommendations such as these. This panel with its now unparalleled understanding of what current literature can as well as what it cannot tell us about surgical management of thyroid disease might suggest ongoing research that will further advance our field and enhance the basis for many of those recommendations currently supported by relatively thin evidence.
Whatever minor limitations this document might have, it nonetheless represents a significant step forward toward standardizing and codifying optimal surgical care of patients with thyroid disease. Patel et al. have unquestionably done clinicians a great service by creating this consensus guideline. It will impact and improve clinical practice and has appeal to a wide audience. But perhaps most important, they have also done a great service to patients everywhere who will benefit because of the sound data analysis and thoughtful recommendations this guideline contains. A rising tide does indeed float all boats.