Relation between acute and late irradiation impairment of four basic tastes and irradiated tongue volume in patients with head-and-neck cancer.
OBJECTIVE
Taste loss is a major cause of morbidity in patients undergoing head-and-neck irradiation. The relationship between the time course and the degree of taste disorder was studied in both acute and late phases.


METHODS
Taste ability was measured by the taste threshold for the four basic tastes using a filter paper disc method in patients before, during, and after radiotherapy. The subjects were divided into two groups. In Group A, the radiation fields included most of the tongue (n = 100), and in Group B the radiation fields did not include the tip of the tongue (n = 18).


RESULTS
In Group A, there was a significant impairment of the threshold of all four basic tastes at 3 weeks after starting radiotherapy (RT), and this impairment remained at 8 weeks (p < 0.05). This was not seen in Group B. In Group A, there was no significant difference in the patterns of taste sensitivity change between the high-dose (>20 Gy) and low-dose (< or =20 Gy) groups. In the late phase, recovery of taste loss was seen in both groups since 4 months after completing RT.


CONCLUSIONS
Unless the anterior part of the tongue was irradiated, taste loss was not observed during RT. When the anterior part of the tongue was irradiated, a difference by radiation dose was not observed in the taste loss pattern. Additionally, radiation-induced taste dysfunction appears to be a temporal effect.
Yamashita
Hideomi
H
Department of Radiology, University of Tokyo Hospital, Tokyo, Japan. yamachan07291973@yahoo.co.jp
Nakagawa
Keiichi
K
Nakamura
Naoki
N
Abe
Keiko
K
Asakage
Takahiro
T
Ohmoto
Makoto
M
Okada
Shinji
S
Matsumoto
Ichiro
I
Hosoi
Yoshio
Y
Sasano
Nakashi
N
Yamakawa
Sen
S
Ohtomo
Kuni
K
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy / Q000532:radiotherapy; D005260:Female; D006258:Head and Neck Neoplasms / Q000188:drug therapy / Q000532:radiotherapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011879:Radiotherapy Dosage; D013649:Taste / Q000528:radiation effects*; D013651:Taste Disorders / Q000209:etiology*; D013652:Taste Threshold; D014059:Tongue / Q000528:radiation effects*