Thyroid Debate
(Papillary Thyroid Cancer:
Extent of Thyroidectomy)
30 Aug 2007
Surgery-OMMC
JGGuerra, MD
HCruz, MD
Papillary Thyroid Cancer: Controversies
in treatment
• Surgical resection is the key to
management of thyroid cancer, but
determining the optimal surgical
procedure for individual cases has been
controversial.
• A prospective, randomized study of total vs
less than total thyroidectomy is impossible
– due to the excellent outcome in the low-risk group
– the requirement of long-term follow-up
– large number of patients needed to show any
statistical difference in long-term survival
outcome.
• Management protocols for WDTC are based
on retrospective data on prognostic indicators
(patient risk and tumor risk factors)
• Clinicians rely on large patient cohort studies
in which therapy has not been randomized,
leading to some disagreement about
management
It is timely to discuss whether total
thyroidectomy is a better treatment option
compared to subtotal thyroidectomy for a
45F with 2 cm papillary thyroid cancer
Premise
Is total thyroidectomy a rational treatment of
choice for a 45F with 2cm papillary thyroid
cancer?
YES
Arguments
1. 30%-87.5% of papillary carcinomas involve
opposite lobe (Hirabayashi, 1961, Russell, 1983)
2. 10%-20% develop recurrence in the contralateral
lobe (Soh, 1996)
3. Lower recurrence rates, some studies show
increased survival (Mazzaferri, 1991)
4. Facilitates earlier detection and tx for recurrent
or metastatic carcinoma with RAI (Soh, 1996)
5. Residual WDTC has the potential to
dedifferentiate to ATC
Literature Review
Databank: Total Thyroidectomy
• Analysis of surgical procedures performed in
over 1500 United States hospitals reveals that
among 5584 patients with thyroid cancer the
majority (77.4%) underwent total
thyroidectomy regardless of tumor histology
and stage (Mazzafferi)
Recurrence rates with lobectomy
• Performing lobectomy alone may result in a 5–
10% recurrence rate in the opposite thyroid
lobe (4,1), a high tumor recurrence rate, and a
high (11%) incidence of subsequent pulmonary
metastases.
Multicentricity
• The fact that local recurrence signifies a
substantial risk of subsequent tumour-related
mortality is emphasized by several workers
• Total thyroidectomy eliminates the
multicentric microscopic foci present in up to
85% of papillary carcinomas6,12 as potential
sites of local recurrence, or the anaplastic
transformation that occurs in 1%3
• Patients undergoing lobectomy have a
recurrence rate in the contralateral lobe of 5
to 25%, with a mean of 7%, and up to onehalf of these patients eventually die of thyroid
cancer, some of whom were initially
considered low risk.5
Cancer mortality rates with lobectomy
• Hay et al. reported that patients treated for lowrisk papillary cancers [Age, Grade, Extent, Size
(AGES) score 3.99] had no improvement in
survival rates after undergoing more than
lobectomy.
• Later, they reported the results of a study
designed to compare outcomes after unilateral or
bilateral lobectomy for papillary cancer
considered to be low risk by AMES criteria.
• Although there were no significant differences in
cancer-specific mortality or distant metastasis
rates between the two groups, the 20-yr rates for
local recurrence and nodal metastasis after
unilateral lobectomy were 14% and 19%,
respectively, significantly higher (P = 0.0001) than
the 2% and 6% rates, respectively, seen after
bilateral thyroid resection
• Hay et al. (30) concluded that bilateral thyroid
resection is the preferable initial surgical
approach to patients with low-risk papillary
cancer
• Tollefsen et al reported a 5.7% local
recurrence rate in the contralateral thyroid
remnant, and 41% of these patients died.
Management Options
BENEFIT
Total
Thyroidectomy
Subtotal
Thyroidectomy
Muticentri
city
RR
RISK for
Complication
COST
AVAILABILITY
1-3% RLN injury
+++
/
<1%
+++
/
Survival
Rate
+
<5%
++
+++
1015%
+
Summary
• Retrospective data showed favorable result for
total thyroidectomy in terms of
– low recurrence rate in the ipsilateral lobe
– prevention of development of cancer on the
contralateral lobe
– acceptable morbidity
– facilitation of post operative treatment
Thank You
References
1.
2.
3.
4.
Clark OH. Total thyroidectomy: the treatment of choice for
patients with differentiated thyroid cancer. Ann Surg 1982; 196:
361—70
Hay ID, Grant CS, Taylor WF, McConahey WM. Ipsilateral
lobectomy versus bilateral lobar resection in papillary thyroid
carcinoma: a retrospective analysis of surgical outcome using a
novel prognostic scoring system. Surgery 1987; 102: 1088—95.
Grant CS, Hay ID, Gough IR, Bergitralb EL, Goellner JR, McConahey
WM. Local recurrence in papillary thyroid carcinoma: is the extent
of surgical resection important? Surgery 1988; 104: 954—62
Mazzaferri EL, Young RL. Papillary thyroid carcinoma: a 10-year
follow-up report of the impact of treatment in 576 patients. Am J
Med 1981; 70: 511—8.
5. McConahey WM, Hay ID, Woolner LB, van Heerden JA, Taylor WE.
Papillary thyroid cancer treated at the Mayo Clinic, 1946 through
1970:initial manifestations, pathologic findings, therapy and
outcome. Mayo Clin Proc 1986; 6: 978—96.
6. Rossi RL, Cady B, Silverman, ML, Wool MS, Homer TA. Current
results of conservative surgery for differentiated thyroid
carcinoma. World JSurg 1986; 10: 612—22.
7. Shah JP, Loree TR, Dharker D, Strong EW. Lobectomy versus total
thyroidectomy for differentiated carcinoma of the thyroid: a
marched-pair analysis. AmJSurg 1993; 166:331—5.
8. Tollefsen HR, Shah, JP, Huvos AG. Papillary carcinoma of the thyroid.
Recurrence in the gland after initial surgical treatment. AmJSurg
1972;124: 468—72.