Predicting nedaplatin sensitivity of cervical cancer using the histoculture drug response assay

Purpose: There are currently no clinically available chemosensitivity assays for cervical cancer. In this study we evaluated whether the histoculture drug response assay (HDRA) could be used to predict chemosensitivity to nedaplatin (NDP) in cervical cancer. Methods: Fifty-four surgical specimens and biopsies from patients with squamous cell carcinoma of the cervix were tested with the HDRA. The results were used to calculate the concentration resulting in 50% inhibition of tumor growth (IC₅₀). We then determined the cut-off concentration for NDP, and investigated the chemosensitivity of NDP for each patient. Moreover, the correlations between chemosensitivity and the clinical response of NDP-containing chemotherapy, and the clinical outcomes of the patients with Stage I and II disease were also investigated. Results: Fifty-one of 54 specimens (94.0%) were evaluable with this assay. The optimal cutoff concentration of NDP was determined to be 48 μg/ml. In 18 patients with measurable lesions, all nine patients in the high sensitive group by HDRA were judged as partial response (PR) to NDP containing chemotherapy. In contrast five of nine patients in the low sensitive group were classified as stable disease, and four were PR. The true positive rate was 100%, the true negative rate was 55.6%, and the accurate prediction rate was 77.8%. Furthermore, the disease-free survival of the high sensitive group tended to be better than that of the low sensitive group in the patients who received postoperative adjuvant chemotherapy with NDP. Conclusions: In the current study, the sensitivity of cervical tumors to nedaplatin was predicted by the HDRA.