Key Background
4
Terms and Definitions
TNM Staging
➤ All ATCs are stage 4 (AJCC 8th Edition). Stage IVA lesions (T1-T3a,
N0, M0) are still localized within the thyroid gland and have not
definitely spread to lymph nodes (N0) or to distant sites (M0). In
Stage IVB ATC, the primary tumor has grown outside/through the
thyroid capsule (T3b, T4) and/or is involving locoregional lymph
nodes (≥N1), but it has not spread to distant sites (M0). In Stage IVC
(Any T, Any N, M1), the tumor has spread to distant site(s).
Extent of Resection
➤ R0 designates complete resection with negative microscopic margins,
R1 designates complete resection of all grossly visible tumors but
with involved surgical resection margins (microscopically involved
resection margins), and R2 designates resection in which gross
cancer was left in place (macroscopically involved resection margins).
Adjuvant Therapy and Neoadjuvant Therapy
➤ Radiation, systemic therapy, or the combination given after surgery
with curative intention is referred to as adjuvant therapy; and when
given before surgery, neoadjuvant therapy.
Table 1. Key Steps in the Management of Anaplastic Thyroid
Cancer (cont'd)
7. Non-surgical management decision making
Other than surgery, options may include post-operative or primary chemoradiation
versus palliative radiotherapy, systemic therapy or best supportive care considered
within the context of:
• Patient goals of care and willingness to accept anticipated toxicities of presented
options
• Patient performance status and comorbidities and their impacts on feasibility of
planned care
• Trade-offs from one approach to care versus alternatives
8. Keep hospice/end of life care discussions in the foreground
• Given the historically dire prognosis of ATC, especially if stage IVC, hospice should
always be presented among care options.
• Truth telling and realistic presentation of anticipated prognosis are critical in allowing
sound patient decisions within their individual goals of care.
• For some patients, hospice may be preferable—even from the outset—in comparison
with other alternative care options.
