Spontaneous Tumor (ST)

Spontaneous tumor lysis syndrome (TLS) is a constellation of electrolyte abnormalities and acute renal failure, which occurs in the setting of rapid cell turnover prior to the administration of cytotoxic chemotherapy. While spontaneous TLS is well described in patients with Burkitt's lymphoma, it is thought to occur less commonly in other hematologic malignancies. A spontaneous tumor incidence of 45% was noted in 360 Sprague-Dawley rats (179 males and 181 females) and a 26% incidence was seen in 254 Swiss mice (101 males and 153 females) used as untreated control animals in an 18-month series of carcinogenesis experiments.