Radiat Oncol J.  2013 Sep;31(3):162-170. 10.3857/roj.2013.31.3.162.

Role of adjuvant postoperative external beam radiotherapy for well differentiated thyroid cancer

Affiliations
  • 1Department of Radiation Oncology, Seoul National University College of Medicine, Seoul, Korea. wuhg@snu.ac.kr
  • 2Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea.
  • 3Institute of Radiation Medicine, Medical Research Center, Seoul National University, Seoul, Korea.
  • 4Department of Surgery, Seoul National University College of Medicine, Seoul, Korea.
  • 5Department of Otolaryngology, Seoul National University College of Medicine, Seoul, Korea.
  • 6Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.

Abstract

PURPOSE
To analyze the outcome of adjuvant postoperative external beam radiotherapy (EBRT) in well-differentiated thyroid cancer (WDTC).
MATERIALS AND METHODS
We identified 84 patients treated with EBRT for WDTC from February 1981 to December 2010. Among them, we analyzed 39 patients who received EBRT after initial radical surgery. Twenty-four females and 15 males were included. The median age was 49 years (range, 16 to 72 years). There were 34 papillary thyroid carcinomas and 5 follicular thyroid carcinomas. Most patients showed pathologic T3/T4 stage (54%/26%). Ten patients (25.6%) had gross residual tumors. Five patients (12.8%) had tumor cells at the margin. The median EBRT dose and fraction size were 62.6 Gy and 1.8 to 2.0 Gy, respectively.
RESULTS
The median follow-up was 73 months (range, 21 to 372 months). The five-year overall survival (OS) and locoregional recurrence free survival (LRFS) were 97.4% and 86.9%, respectively. Locoregional failures occurred in 5 and all failure sites were the neck node area. In univariate analysis, OS was significantly influenced by invasion of the trachea (p = 0.016) or esophagus (p = 0.006). LRFS was significantly decreased by male (p = 0.020), gross residuum after resection (p = 0.002), close or positive tumor at surgical margin involvement (p = 0.044), and tracheal invasion (p = 0.040). No significant prognostic factor was identified in the multivariate analysis. No patient experienced the Radiation Therapy Oncology Group grade 3 or more toxicity.
CONCLUSION
Our locoregional control rate of 87.2% is comparable to historical controls with surgery alone, even though our study had a large proportion of advanced stage. Adjuvant EBRT may an effective and safe treatment option in patients with WDTC.

Keyword

Papillary thyroid cancer; Follicular thyroid cancer; Radiotherapy; Adjuvant

MeSH Terms

Adenocarcinoma, Follicular
Esophagus
Female
Follow-Up Studies
Humans
Male
Multivariate Analysis
Neck
Neoplasm, Residual
Recurrence
Thyroid Gland
Thyroid Neoplasms
Trachea
Full Text Links
  • ROJ
Actions
Cited
CITED
export Copy
Close
Share
  • Twitter
  • Facebook
Similar articles
Copyright © 2024 by Korean Association of Medical Journal Editors. All rights reserved.     E-mail: koreamed@kamje.or.kr