Gastric emptying function changes in patients with thyroid cancer after withdrawal of thyroid hormone therapy.
BACKGROUND
Hypothyroidism is commonly thought to cause decreased gastric emptying but is mostly associated with autoimmune disease. In the present study the gastric emptying function of thyroid cancer patients with severe hypothyroidism of short duration was evaluated with a radionuclide solid meal gastric emptying study.


METHODS
Twenty-two patients who had undergone surgical operation and (131)I ablation for thyroid cancer participated in solid meal gastric emptying studies before the withdrawal of thyroxine and then again 4 weeks after the withdrawal of thyroxine. Eleven patients had an additional gastric emptying study at 6 weeks after withdrawal of thyroxine. Gastric emptying curves and emptying parameters were calculated. Student's paired t-test was used for statistical analysis of data for all cases between the baseline and at 4 weeks after withdrawal. An additional repeated measure anova with multiple comparisons was performed on data between baseline, 4 weeks and 6 weeks after withdrawal for the other 11 patients. All P values presented are two-tailed and the significance level is 0.05.


RESULTS
Hypothyroidism status was confirmed by the marked change of the serum thyroxine and thyroid-stimulating hormone 4 weeks and 6 weeks after withdrawal of the thyroxine replacement (P < 0.001). The gastric half-emptying time and emptying rate changed significantly after short-term severe thyroid hormone deficiency (P < 0.005). However, the length of the lag phase did not have a statistically significant change at 4 weeks or 6 weeks after withdrawal of the thyroxin replacement (P = 0.219 and 0.142).


CONCLUSIONS
Hypothyroidism following the withdrawal of the thyroxine replacement in thyroid cancer patients preparing for (131)I cancer work-up can significantly prolong gastric half-emptying time and emptying rate.
Kao
Pan-Fu
PF
Department of Nuclear Medicine, Chang Gung Memorial Hospital, Taipei, Taiwan. kao-panfu@umail.hinet.net
Lin
Jen-Der
JD
Chiu
Cheng-Tang
CT
Hsu
Hui-Ting
HT
See
Lai-Chu
LC
Tzen
Kai-Yuan
KY
D000208:Acute Disease; D000328:Adult; D000368:Aged; D004334:Drug Administration Schedule; D005260:Female; D005746:Gastric Emptying; D006801:Humans; D007037:Hypothyroidism / Q000150:complications* / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011877:Radionuclide Imaging; D013964:Thyroid Neoplasms / Q000150:complications*; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000008:administration & dosage* / Q000097:blood / Q000172:deficiency
D013972:Thyrotropin; D013974:Thyroxine