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Subgrouping of N1a Stage Papillary Thyroid Carcinoma with Positive Node Ratio

갑상선유두상암의 중앙림프절 전이율에 따른 N1a병기의 세분화

  • 이민완 (전남대학교 의과대학 외과학교실) ;
  • 조진성 (전남대학교 의과대학 외과학교실) ;
  • 조동훈 (전남대학교 의과대학 외과학교실) ;
  • 유영재 (전남대학교 의과대학 외과학교실) ;
  • 박민호 (전남대학교 의과대학 외과학교실) ;
  • 윤정한 (전남대학교 의과대학 외과학교실)
  • Received : 2016.05.06
  • Accepted : 2016.05.23
  • Published : 2016.05.30

Abstract

Background : The 2015 American thyroid association (ATA) guidelines greatly expanded section on risk stratification of thyroid cancer. Definition of "Low risk of recurrence" has expanded, by inclusion of small volume lymph node involvement, such as less than 5 lymph node metastases each smaller than 2mm in central compartment. Purpose : We evaluated the number of positive nodes, Positive node ratio (PNR), recurrence, and radioablation therapy. Also, evaluated the safety of omitting strategy of radioablation after total thyroidectomy with PTC, especially on low-PNR N1a patients compared with high-PNR N1a patients. Methods : Consecutive 147 N1a and 216 N0 patients who underwent total thyroidectomy with central neck dissection between 2003 and 2004 were enrolled. We divided 147 N1a patients into two groups, such as 96 high-PNR versus 51 low-PNR group according to 50% of PNR, and compared these two groups with N0 group. Results: 7.2% (26/363) recurrences were occurred, and 21/147 (14.3 %) recurrences were on N1a patients, and 5/216 (2.3 %) were on N0 patients. Of these 21 recurrences in N1a stage patients, 20 (95.2 %) recurrences were occurred in high-PNR N1a group and only 1 (4.8 %) recurrence was in low-PNR N1a group. The recurrence of low-PNR N1a group was significantly lower than high-PNR N1a group (Log-rank p value = 0.003), but significantly not different from N0 group (Log-rank p value = 0.889). Although this study was a retrospective non-randomized trial with small number of patients, the 10-year recurrence of omitting RAI in low-PNR N1a patients with less than 50% of PNR were shown to be comparable with 216 N0 low risk patients. Conclusion : Positive node ratio could be a useful predictor of recurrence and useful guidance postoperative management -rather than absolute number of positive node.

Keywords

References

  1. Mazzaferri EL, Kloos RT. Clinical review 128: Current approaches to primary therapy for papillary and follicular thyroid cancer. J Clin Endocrinol Metab 2001;86:1447-1463. https://doi.org/10.1210/jcem.86.4.7407
  2. Hay ID, Bergstralh EJ, Goellner JR, Ebersold JR, Grant CS. Predicting outcome in papillary thyroid carcinoma: development of a reliable prognostic scoring system in a cohort of 1779 patients surgically treated at one institution during 1940 through 1989. Surgery 1993;114:1050-1057; discussion 1057-1058.
  3. Cho JS, Yoon JH, Park MH, Shin SH, Jegal YJ, Lee JS, et al. Age and prognosis of papillary thyroid carcinoma: retrospective stratification into three groups. J Korean Surg Soc 2012;83:259-266. https://doi.org/10.4174/jkss.2012.83.5.259
  4. Ito Y, Masuoka H, Fukushima M, Inoue H, Kihara M, Tomoda C, et al. Excellent prognosis of patients with solitary T1N0M0 papillary thyroid carcinoma who underwent thyroidectomy and elective lymph node dissection without radioiodine therapy. World J Surg 2010;34:1285-1290. https://doi.org/10.1007/s00268-009-0356-0
  5. Yamashita H, Noguchi S, Murakami N, Kawamoto H, Watanabe S. Extracapsular invasion of lymph node metastasis is an indicator of distant metastasis and poor prognosis in patients with thyroid papillary carcinoma. Cancer 1997;80:2268-2272. https://doi.org/10.1002/(SICI)1097-0142(19971215)80:12<2268::AID-CNCR8>3.0.CO;2-Q
  6. Cho BY, Choi HS, Park YJ, Lim JA, Ahn HY, Lee EK, et al. Changes in the clinicopathological characteristics and outcomes of thyroid cancer in Korea over the past four decades. Thyroid 2013;23:797-804. https://doi.org/10.1089/thy.2012.0329
  7. Cobin RH, Gharib H, Bergman DA, Clark OH, Cooper DS, Daniels GH, et al. AACE/AAES medical/surgical guidelines for clinical practice: management of thyroid carcinoma. American Association of Clinical Endocrinologists. American College of Endocrinology. Endocr Pract 2001;7:202-220. https://doi.org/10.4158/EP.7.3.202
  8. Haugen BR, Alexander EK, Bible KC, Doherty GM, Mandel SJ, Nikiforov YE, et al. 2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer: The American Thyroid Association Guidelines Task Force on Thyroid Nodules and Differentiated Thyroid Cancer. Thyroid 2016;26:1-133. https://doi.org/10.1089/thy.2015.0020
  9. Kim WB, Kim TY, Kwon HS, Moon WJ, Lee JB, Choi YS, et al. Review Articles : Management Guidelines for Patients with Thyroid Nodules and Thyroid Cancer. Endocrinology and metabolism 2007;22:157-187.
  10. Yi KH, Park YJ, Koong SS, Kim JH, Na DG, Ryu JS, et al. Revised Korean Thyroid Association Management Guidelines for Patients with Thyroid Nodules and Thyroid Cancer. Endocrinology and metabolism 2010;25:270-297. https://doi.org/10.3803/EnM.2010.25.4.270
  11. American Thyroid Association Guidelines Taskforce on Thyroid N, Differentiated Thyroid C, Cooper DS, Doherty GM, Haugen BR, Kloos RT, et al. Revised American Thyroid Association management guidelines for patients with thyroid nodules and differentiated thyroid cancer. Thyroid 2009;19:1167-1214. https://doi.org/10.1089/thy.2009.0110
  12. Ryu IS, Song CI, Choi SH, Roh JL, Nam SY, Kim SY. Lymph node ratio of the central compartment is a significant predictor for locoregional recurrence after prophylactic central neck dissection in patients with thyroid papillary carcinoma. Ann Surg Oncol 2014;21:277-283. https://doi.org/10.1245/s10434-013-3258-1
  13. Lee SG, Ho J, Choi JB, Kim TH, Kim MJ, Ban EJ, et al. Optimal Cut-Off Values of Lymph Node Ratio Predicting Recurrence in Papillary Thyroid Cancer. Medicine 2016;95.
  14. Cooper DS, Doherty GM, Haugen BR, Kloos RT, Lee SL, Mandel SJ, et al. Management guidelines for patients with thyroid nodules and differentiated thyroid cancer. Thyroid 2006;16:109-142. https://doi.org/10.1089/thy.2006.16.109
  15. Ahn HS, Kim HJ, Welch HG. Korea's thyroid-cancer "epidemic"--screening and overdiagnosis. N Engl J Med 2014;371:1765-1767. https://doi.org/10.1056/NEJMp1409841
  16. Lee YS, Chang HS, Park CS. Changing trends in the management of well-differentiated thyroid carcinoma in Korea. Endocr J 2016.
  17. Davies L, Welch HG. Current thyroid cancer trends in the United States. JAMA otolaryngology-- head & neck surgery 2014;140:317-322. https://doi.org/10.1001/jamaoto.2014.1
  18. Kim B, Yousman WP, Wong WX, Cheng C, McAninch EA. Less is More: Comparing the 2015 and 2009 American Thyroid Association Guidelines for Thyroid Nodules and Cancer. Thyroid 2016.