Triumph Over Butchery: Guest Editorial for Indian Journal of Surgical Oncology

Abstract

While once considered “butchery,” thyroid cancer surgery is now considered a safe surgery in the setting of the increasing incidence of thyroid nodules. Several changes in the approach to patients and advancements in technology have paved the way for the technical feasibility of thyroid surgery. International guidelines have enabled a personalized, and less invasive approach to patients and thus reducing the morbidity attributed tumors from potential injury to the recurrent laryngeal nerve or long-term thyroid hormone replacement- particularly for papillary microcarcinomas. Morbidity from hypocalcemia and nerve injury have further been improved by advancements including parathyroid localizing technology, nerve monitoring, molecular testing, and improved diagnostic imaging. As we continue to improve our understanding of the thyroid, so will the outcomes of patients who undergo thyroid cancer surgery. Advancements in the safety and feasibility of thyroid surgery remind us of the statement made by William Halsted: “thyroid surgery is a supreme triumph of the surgeon’s heart.”

It is a great honor for me to write this editorial for the Indian Journal of Surgical Oncology as Dr. Gopinath is completing his impressive 10-year tenure as chief editor. Dr. Gopinath’s contributions in the field of surgical oncology are well-known worldwide, and I must congratulate him for an illustrious career, which has helped elevate surgical oncology in India.

I have chosen the subject of “triumph over butchery” as these two words have revolutionized our approach toward thyroid surgery. Thyroid surgery was once considered to be horrid butchery by Samuel Gross in 1866. The mortality rate from thyroid surgery reported by Billroth was 40% when initially performed [1]. The French Academy abandoned thyroid surgery as an option for patients. Credit goes to Theodor Kocher, who perfected the surgical technique and reduced mortality in thyroid surgery to less than 0.5%. His contribution to surgery and to the physiology of the thyroid led him to win the Nobel Prize in Medicine in 1909. William Halsted practically brought thyroid surgery to the United States and mentioned thyroid surgery as a supreme triumph of surgeon’s art. Clearly, we have now swung from horrid butchery to surgical triumph [2].

In the last 125 years, we have seen several advances in thyroid surgery, and it has become one of the most common surgical procedures. The incidence of thyroid nodules and thyroid cancer has almost quadrupled all over the world. This is primarily due to the routine use of ultrasound and other imaging studies. It is not uncommon to find thyroid nodules during other routine imaging studies, which are described as incidentalomas. This has been vividly described in South Korean literature with a 15-fold rise in thyroid cancer [3]. There seems to be a considerable paradigm shift in the standardization of the needle biopsy to avoid overdiagnosis and overtreatment of thyroid diseases. Several organizations have developed classification systems based on ultrasound findings (TIRADS). TIRADS described by the American College of Radiology, American Thyroid Association, and the Korean group have been most commonly used. Despite this, several patients demand fine needle aspiration biopsy and surgery if the needle biopsy is suspicious or atypical and if the thyroid nodule is large. There has been considerable interest in molecular analysis in atypical needle biopsies. These investigations are prohibitively expensive and probably unavailable in the rest of the world. Molecular analysis does have a definite role in advanced thyroid carcinoma or recurrent thyroid cancer and—as shown recently—in anaplastic thyroid cancer [4]. Practically, anaplastic thyroid cancer is divided between BRAF-positive and BRAF-negative. We have seen very promising results in BRAF-positive anaplastic thyroid cancer with a remarkable improvement in survival in a disease that was universally fatal. Newer targeted therapies with Dabranfenib and Trametinib helped considerable improvement in this deadly disease [5]. Immunotherapy is also used along with targeted therapy [6].

Technology has played an important role in thyroid surgery. For example, Advances that have changed our surgical approach have included intraoperative nerve monitoring [7, 8]. Recurrent laryngeal nerve injury was classically described as one of the most common major injuries in thyroid surgery. Recurrent laryngeal nerve injury can lead to hoarseness in the case of unilateral injury and devastatingly dyspnea requiring tracheostomy in bilateral injuries. The introduction of nerve monitoring provides feedback to the surgeon in terms of differentiating the nerve from other major structures, particularly for patients who had recurrent disease, radiation, or large tumors/goiters. Classically, the adoption of nerve monitoring was controversial and true impact on clinical benefit remained unclear. More recent data, however, has demonstrated nerve monitoring to reduce the risk of transient and permanent recurrently laryngeal nerve injury [9, 10]. In addition, the nerve monitor has aided in helping to identify a nerve injury and whether contralateral lobe resection should be pursued in the setting where the nerve on the operative side is no longer functional and staged total thyroidectomy should be pursued. Nerve monitoring has nonetheless less become an aid in the surgeon’s armamentarium that has improved outcomes in patients with thyroid pathology.

Along the same lines as nerve monitoring, technology dedicated to the identification of parathyroids has led to safer surgery in the neck. Development of hypoparathyroidism after thyroid surgery has been quoted to be 5–22% [11] and even experienced surgeons find identification of all four glands during total thyroidectomy to be challenging. The recent development of parathyroid localizing technology has shown increasing promise, in particular, direct visualization using near-infrared autofluorescence (NIRAF) [12, 13]. NIRAF has gained wide appreciation for its ability to detect not only adenomas but also normal parathyroid glands intraoperatively in real time for the surgeon. Still, its widespread use has remained limited. Studies evaluating its use have demonstrated a significant reduction in severe hypocalcemia but no difference in transient hypocalcemia or inadvertent parathyroid resection [14–16]. Still, its safety profile combined with its potential for identifying parathyroids not otherwise easily identified has led to FDA approval of NIRAF for clinical use [17]. While ongoing studies will be useful in determining the indications and patients that would benefit from its use, this emerging technology once again demonstrates that ongoing progress that has been made to performing safer surgery.

There recently has been substantial interest in endoscopic thyroidectomy to avoid a scar in the neck. Initially, there was considerable interest in trans-axillary, trans-mammary, and sub-mammary approaches to the thyroid with or without a robot [18]. This subject generates considerable interest and debate, as the majority of scars from open thyroidectomy practically become undetectable after a few years. Robotic involvement has been applied to thyroid surgery, but once again the cost is a consideration. Transoral endoscopic thyroidectomy appears to have become quite popular in the last 10 years and is gaining additional interest in developing countries [19]. The idea of remote access thyroid surgery is to avoid a scar in the neck; however, it should be recognized that a properly placed incision is practically unrecognizable. The cost and complications of remote access surgery need to be considered in the application of these nuances.

With the rapid rise in micropapillary thyroid carcinoma, there is considerable interest now in active surveillance, akin to prostate cancer [20, 21]. This has been accepted worldwide, and several reports have been published from different countries with approximately 5% increase in the size of thyroid tumors and 2% increase in nodal metastasis. However, this has not changed the overall incidence of recurrence or mortality. Micropapillary carcinoma has the best outcome of approximately 99.5% 10-year survival.

De-escalation of care has also contributed to the improvement in surgical outcomes for patients. Central compartment dissection is recommended for patients with preoperatively identified nodal disease, yet the use of prophylactic central dissection remains dependent on patient selection. Proponents of prophylactic dissection state that the procedure enables evaluation of micrometastatic disease which has been supported by reports that demonstrate lower thyroglobulin levels in central dissection patients. In addition, consideration for prophylactic central dissection reduces the risk of reoperating in the central neck which is technically more difficult in the reoperative setting [22, 23]. However, prophylactic dissection is carefully considered as it is not without inherent risks including transient hypocalcemia and nerve injury without a survival benefit [24]. Randomized trials that attempted to answer the question of the clinical utility of prophylactic central node found no statistically significant difference in short-term outcomes but higher than expected complications including hypoparathyroidism [25, 26]. Thus, the use of prophylactic dissection has waned and led to the safer practice of thyroid surgery.

In addition to surgical de-escalation in therapy, the de-escalation of optimal medical therapy allowed for great strides to be made in thyroid carcinomas. In 2009, the American Thyroid Association introduced into its guidelines that the use of radioactive iodine (RAI) could be omitted for patients with low-risk thyroid carcinomas [27]. The de-escalation in RAI for all thyroid carcinomas signaled that thyroid carcinomas could be stratified by aggressiveness and outcomes. An omission of RAI allowed surgeons to consider thyroid lobectomy for lower-risk carcinomas, thus avoiding the morbidity associated with total thyroidectomy. This change in the approach heralded a major change that was adopted across multiple societies and introduced an era of individualized care to every patient with thyroid carcinomas that evaluated the stage of disease and patient/tumor factors to optimize the treatment of patients—promoting an oncologically sound and, most importantly, safer approach to patients.

We have made remarkable progress in thyroid surgery. The understanding of the prognostic factors and risk-group analysis has divided thyroid tumors into good, bad, and ugly (low, intermediate, and high-risk). The American Thyroid Association has done a remarkable job in developing guidelines for well-differentiated, medullary, and anaplastic thyroid cancer. These guidelines have become a cornerstone of the management of thyroid tumors everywhere. The staging system and the current 8th edition have used the biological behavior of thyroid tumors in the appropriate staging. We have come a long way from horrid butchery to surgical triumph.