[Substance P and anticancer drug-induced emesis].

BACKGROUND

Cytotoxic drug-induced emesis is the side effect most feared by cancer patients. The Acute emesis has become well controlled by the emergence appearance of 5-HT3 receptor antagonist, but control of delayed emesis (DE) is insufficient. The mechanism of DE is different from acute emesis,and the existence of a mediator different from serotonin is contemplated. There were some reports suggesting the role of substance P (SP) and its receptor, neurokinin receptor 1 (NK 1), in the development of emesis.

OBJECTIVE

We investigated the relationship between DE and SP in patients treated with anticancer agents.

METHODS

Digestive cancer and breast cancer patients, who were administered cytotoxic agents, were the objects of this study. We measured plasma levels of SP for 20 cases on the day before administration of anticancer agents and for five days after administration.

RESULTS

Plasma levels of SP increased significantly on the first and third days after administration. In the patient who experienced DE, the difference in plasma levels on the day before and the first day after chemotherapy was higher than that of who never experienced.

CONCLUSIONS

The plasma levels of SP were transiently increased by chemotherapy. The difference in plasma levels between the day before and the first day after chemotherapy is important.