Subrenal capsule assay for squamous cell carcinoma of the head and neck.

Abstract

The murine subrenal capsule assay is an in vivo method for determining the responsiveness of solid tumor xenografts to chemotherapeutic agents. It was used in this study for the purposes of constructing growth curves of squamous cell carcinoma of the head and neck and collecting pilot data on the effects that indomethacin and cisplatin have on this malignant condition. Nine of the ten assays performed were evaluable. Indomethacin, cisplatin, or both were used as treatment drugs in each assay. One-millimeter fragments of viable tumor, from patients with head and neck squamous cell carcinoma, were implanted beneath the renal capsules of normal immunocompetent mice. Baseline and posttreatment measurements were made of the xenografts, and response to treatment was determined by comparing changes in tumor sizes of the test and control groups. Results indicated that reduction in tumor sizes occurred in indomethacin-treated mice in four assays and in cisplatin-treated mice in six assays. In addition, two separate growth curves were calculated by plotting the mean change in tumor size in five mice per day on days 3 through 7. In conclusion, the subrenal capsule assay is a relatively rapid and inexpensive assay in which squamous cell carcinoma remains viable and therapeutic agents can be tested. However, clinical trials that use this assay to choose treatment drugs are needed in order to correlate assay results with clinical responses.