The Reliability of Histoculture Drug Response Assay (HDRA) in Chemosensitivity Tests for Breast Cancer

Cancers are highly individual in their response to chemotherapy, however attempts to predict tumor response to drugs using in vitro cell culture have largely failed. A new technology, the histoculture drug response assay (HDRA), appears to have solved many previous problems. The purpose of this study is to evaluate the reliability of HDRA in a chemosensitivity test for breast cancer.

Tumor specimens from breast cancer patients were evaluated by HDRA using different chemotherapeutic agents. Each specimen was tested using a blind method in order to determine the reproducibility of HDRA results for the same tissue and with a triplicated assay in order to determine reproducibility by different examiners. The evaluative power of this assay and the chemosensitivity of drugs for each specimen was determined.

Specimens of 92.9% (65/70) were successfully cultured and evaluated for chemosensitivity. The reproducibility of HDRA for the same tissue was 75% (100% agreement) and 100% (over 70% agreement), respectively. And the reproducibility by different examiners was 78.9% (100% agreement) and 94.7% (over 70% agreement), respectively. Each specimen demonstrated a response to at least one agent.

The evaluative power and reproducibility of HDRA were high, therefore it might serve as a reliable clinical method for chemosensitivity testing. However, there is a need for clinical trial in which patients are initially randomized for treatment either by HDRA direction or by clinician's choice.