Gustatory impairment and salivary gland pathophysiology in relation to oral cancer treatment.

Gustation and salivation were evaluated in 41 patients with oral carcinoma who were treated preoperatively with Peplomycin (PLM) or PLM + 5-FU + 60CO- radiation. Thresholds for sweet, salt, sour and bitter were originally elevated in many patients. Gustatory impairment increased especially with chemo- and radiotherapy. Recovery, however, took place within a year to almost original levels. Salivation was originally not impaired. Resting salivary flow rate (SFR) of the combined therapy group was decreased to half the initial rate, and a 20% decrease of SFR was seen in the PLM group. Corresponding to SFR, 99mTc uptake of the submandibular glands had declined, and salivary viscosity had increased. Salivary gland damage persisted during the study, and appeared irreversible. It was concluded from these results that taste impairment by oral cancer treatment is temporary, while damage to the salivary glands is permanent.