Two types of tumour sensitivity test compared for platinum derivatives

Area of Science:

• Oncology
• Pharmacology
• Experimental Medicine

Background:

• Accurate prediction of patient response to cytostatic drugs is crucial for effective cancer treatment.
• Early passages of human tumors in animal models are used to test drug sensitivity.
• Platinum compounds are a key class of chemotherapeutic agents.

Purpose of the Study:

• To evaluate two predictive assays for cytostatic drug sensitivity in early human tumor passages.
• To assess the reliability of the subrenal capsule assay and the clonogenic assay for platinum compounds.

Main Methods:

• Testing of four platinum compounds on 15 early human tumor passages grown in nude mice.
• Application of the subrenal capsule assay (Bogden) and the clonogenic assay (Hamburger and Salmon).
• Analysis of assay reproducibility and reliability in predicting drug sensitivity.

Main Results:

• The subrenal capsule assay yielded results not significantly different from random, deeming it unsuitable for early passages.
• The clonogenic assay provided reproducible results for tumors forming colonies in vitro, but with occasional irregular growth.
• Anomalous findings, such as lower drug concentrations being more effective, raised concerns about the assay's reliability.
• Optimal drug concentrations for testing may not uniformly correlate with peak plasma levels.

Conclusions:

• The subrenal capsule assay is not reliable for predicting platinum compound sensitivity in early tumor passages.
• The clonogenic assay shows potential but requires further refinement due to observed irregularities and unreliable results in some cases.
• Current predictive assays may not accurately reflect in vivo drug effectiveness, necessitating improved methodologies.