Current Issues in Thyroid Cancer Surgery in 2017

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1 Current Issues in Thyroid Cancer Surgery in 2017 Dr. David Goldstein MD Msc FRCSC FACS Associate Professor, Department Otolaryngology Head & Neck Surgery, U of T Department of Surgical Oncology, Princess Margaret Cancer Center

2 Objectives To discuss current issues in the surgical management of thyroid cancer Extent of thyroidectomy Role of neck dissection Highlight the importance of multidisciplinary team in treatment decisions in the current era Nothing to disclose

3 Question

4 Differentiated Cancer of the Thyroid Gland Previous Approach Subtotal or near total thyroidectomy Radioiodine ablation Radioiodine therapy Follow up with TGb and ultrasound

5 Extent of Surgery 2009 for pts with TC > 1cm the initial surgical procedure should be a near-total or total thyroidectomy unless there are contraindications to surgery.

6 Proponents for Total Thyroidectomy?? Lower recurrence rates?? Better overall survival Allows for RAI Enhances monitoring for recurrence with thyroglobulin Addresses contralateral disease Multifocality 30-85% No need for completion surgery if adverse pathologic features or nodes on final path In experienced hands low risk of complications Less frequent monitoring with US Surgery for recurrence is associated with increased morbidity

7 Differentiated Cancer of the Thyroid Gland Previous Approach Subtotal or near total thyroidectomy Radioiodine ablation Radioiodine therapy If we follow this practice Follow up with TGb and ultrasound Majority get excessive treatment at great cost with little or no benefit

8 Need to apply Surgical Oncologic Principles to Thyroid Cancer Resection of cancer with clear margins while reducing morbidity Just because you can remove a whole organ does not mean one should Data does not support worse outcomes with hemithyroidectomy compared with total thyroidectomy in patients with low risk tumors

9 Proponents of thyroid lobectomy Lower rates of : RLN Injury Transient RR 1.7, Permanent RR 1.9 Bilateral Hypoparathyroidism Hematoma Thyroid hormone replacement High res US & sensitive Tg assays enable surveillance for recurrence w/o RAI remnant ablation Starting to understand QoL after TT may have substantial difficulties despite optimal replacement

10 Extent of Surgery 2017 Selected patients may be potentially treated with lobectomy alone unifocal tumors < 4cm and no evidence of ETE or lymph node metastases microcarcinomas (<1cm)- Lobectomy should be chosen if surgery is performed rather than may be chosen Treatment team may choose TT to enable RAI therapy or enhance follow up based upon disease features and patient preference ATA Guidelines 2015

11 Why a Change? Expansion of the definition of a low risk tumor Decreasing indications for 131I therapy and scanning Critical re-assessment of studies comparing outcomes with lobectomy with total thyroidectomy Belief that salvage therapy is effective in most cases if persistent/recurrent disease is identified

12 Drawbacks with lobectomy Need for completion thyroidectomy Kluijfhout et al Surgery

13 WHEN TO COMPLETE

14 How to decide: Importance of MDT Multidisciplinary Care Would this patient benefit radioactive iodine treatment in order to reduce recurrence or Tg monitoring is essential Patient s input

15 Surgeon Volume & Improved Outcomes High volume surgeons were more likely to perform: Total thyroidectomy Neck dissection Shorter LOS Lower complications Multi-disciplinary care Gourin CG et al. Arch Otol Head and Neck Surg 2010

16 Nodal Metastases LATERAL NECK DISSECTION CENTRAL NECK DISSECTION

17 Lateral Neck Dissection Indications Only when there is clinically/radiographically detectable nodal metastases No role for prophylactic lateral neck dissection (ie cn0) One caveat 2015 ATA guidelines suggest a > 8 10 mm smallest diameter specific size threshold suggested for lymph node FNA (Rec 32 B)

18 Central Neck Dissection Definite indication clinically/radiographically detectable central neck nodal disease Controversy cn0 patient? Role of prophylactic CCND

19 Arguments in favour and/or Against CCND Regional LN micro- mets - 38%-62% of PTC patients Same is true for lateral neck yet prophylactic lateral ND clearly not indicated Lymph node mets have a negative impact on patient outcome & CCND can upstage patient further treatment May be true in the older patient but not the younger patient, little evidence in low risk patient Micrometastases to nodes do not have an impact on survival Safe procedure in experienced hands Most thyroid surgery not performed by experts

20 Arguments in favour & Against CCND Reoperation for central neck recurrence has greater morbidity based on retrospective chart reviews No clear data to suggest CCND reduces need for reoperation Complication rates still relatively low Not all central recurrence needs surgery based on Tuttle et al Lower post-op Tg levels (Delbridge et al) Data not consistent- Hughes et al showed post-trt Tg levels no different between TT alone vs TT with CCND So what? No difference in locoregional recurrence or disease specific mortality Less relevant as move to less than total thyroidectomies

21 Management of Lymph Node Metastases ATA Guidelines 2015 Prophylactic CND now deemed reasonable if lateral nodes are clinically involved or if the information will be used to plan further steps in therapy when primary tumor known to be advanced (T3 or T4)

22 Conclusions Lobectomy vs Total Thyroidectomy in Low to Intermediate risk Disease Lower complication rate even in high volume centers Similar oncologic outcomes Low Risk Patient selection important and parameters for completion thyroidectomy and RAI must be defined Better quality of life? MDT or care is integral in decision making particular in the grey zones High volume surgeons/centers better outcomes No role for prophylactic CND in majority of cn0 patients

23 Thank you QUESTIONS?