Administration of Radioactive Iodine Therapy Within 1 Year After Total Thyroidectomy Does Not Affect Vocal Function.
The purpose of this study was to evaluate the impact of radioactive iodine therapy (RIT) on vocal function during the early follow-up period after total thyroidectomy (TT) using perceptive and objective measurements, questionnaires regarding subjective symptoms, and data on vocal function in a prospectively enrolled and serially followed thyroid cancer cohort.


METHODS
Of 212 patients who underwent TT and were screened between January and December 2010 at our hospital, 160 were included in the final analysis. Patients with the following histories were excluded: lateral neck dissection, organic vocal fold disease, external radiotherapy, and voice evaluation during thyroxine withdrawal. Patients were stratified into 3 groups: TT, TT with low-dose RIT (1.1-2.2 GBq), and TT with high-dose RIT (≥3.7 GBq). Voice evaluations were performed before surgery and at 1, 6, and 12 mo after TT.


RESULTS
Vocal characteristics were altered after TT, including changes on the grade, roughness, and strain scale; increased amplitude perturbation; decreased fundamental frequency; narrowed pitch range; and global disturbances in subjective functional parameters on the voice handicap index. However, the degree of vocal changes among the 3 groups did not significantly differ within the 1-y postoperative follow-up period. According to the results of subgroup analyses of patients who demonstrated good voice outcomes after TT, there were no significant functional differences among the 3 groups.


CONCLUSIONS
RIT at any dose does not affect vocal function within 1 y of TT.
Department of Otolaryngology-Head and Neck Surgery, Center for Thyroid Cancer, Research Institute and Hospital, National Cancer Center, Goyang-si, Gyeonggi-do, Korea.
Chang Hwan
CH
Ryu
Department of Otolaryngology-Head and Neck Surgery, Center for Thyroid Cancer, Research Institute and Hospital, National Cancer Center, Goyang-si, Gyeonggi-do, Korea.
Junsun
J
Ryu
Department of Otolaryngology-Head and Neck Surgery, Center for Thyroid Cancer, Research Institute and Hospital, National Cancer Center, Goyang-si, Gyeonggi-do, Korea.
Youn Mi
YM
Ryu
Department of Internal Medicine, Center for Thyroid Cancer, Research Institute and Hospital, National Cancer Center, Goyang-si, Gyeonggi-do, Korea.
You Jin
YJ
Lee
Department of Internal Medicine, Center for Thyroid Cancer, Research Institute and Hospital, National Cancer Center, Goyang-si, Gyeonggi-do, Korea.
Eun-Kyung
EK
Lee
Department of Nuclear Medicine, Center for Thyroid Cancer, Research Institute and Hospital, National Cancer Center, Goyang-si, Gyeonggi-do, Korea.
Seok-Ki
SK
Kim
Department of Nuclear Medicine, Center for Thyroid Cancer, Research Institute and Hospital, National Cancer Center, Goyang-si, Gyeonggi-do, Korea.
Tae-Sung
TS
Kim
Department of Radiation Oncology, Center for Thyroid Cancer, Research Institute and Hospital, National Cancer Center, Goyang-si, Gyeonggi-do, Korea.
Tae Hyun
TH
Kim
Department of Radiology, Center for Thyroid Cancer, Research Institute and Hospital, National Cancer Center, Goyang-si, Gyeonggi-do, Korea.
Chang Yoon
CY
Lee
Department of Pathology, Center for Thyroid Cancer, Research Institute and Hospital, National Cancer Center, Goyang-si, Gyeonggi-do, Korea; and.
Seog Yun
SY
Park
Department of Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
Ki Wook
KW
Chung
Department of Otolaryngology-Head and Neck Surgery, Center for Thyroid Cancer, Research Institute and Hospital, National Cancer Center, Goyang-si, Gyeonggi-do, Korea jysorl@ncc.re.kr.
Yuh-S
YS
Jung
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes / Q000009:adverse effects*; D007828:Laryngoscopy; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000503:physiopathology; D013964:Thyroid Neoplasms / Q000150:complications / Q000532:radiotherapy / Q000601:surgery; D013965:Thyroidectomy; D014827:Vocal Cords / Q000473:pathology; D014831:Voice / Q000528:radiation effects*; D014832:Voice Disorders / Q000453:epidemiology*
D007457:Iodine Radioisotopes
radioactive iodine; thyroid cancer; total thyroidectomy; voice