In vitro chemoresponse to cisplatin and outcomes in cervical cancer

Objective The aim of this study was to report clinical outcomes of cervical cancer patients treated with weekly cisplatin chemo-radiation therapy (chemoRT) stratified by pre-treatment cisplatin in vitro chemosensitivity. Methods This was a retrospective analysis of patients with cervical cancer seen at our institution between May 2009 and August 2011. Patients underwent pre-treatment in vitro chemoresponse testing (Precision Therapeutics, Inc.) and were treated with concurrent weekly cisplatin chemoRT. The study consisted of 33 patients with FIGO tumor stages Ib2 to IIIb. Pre-treatment cisplatin chemoresponse of individual patient tumors was determined from chemoresponse dose response curves and scored as responsive (R), intermediate response (IR), or nonresponsive (NR). Results There were 28 patients with squamous cell carcinoma and 5 with adenocarcinoma. Cisplatin chemosensitivity was R and IR in 18 patient specimens and NR in 15. The 2-year recurrence-free survivals (RFS) were 87% for patients whose specimens tested R+IR to cisplatin compared to 58% for those whose specimens were NR (p=0.036). The 2-year RFS were 86% for the R+IR group compared to 46% for the NR group for patients with tumors of squamous cell histology (p=0.009). Stepwise proportional hazards modeling for RFS demonstrated that chemoresponsiveness to cisplatin (p=0.029) and FDG-PET lymph node status (p=0.011) were the only independent predictors of RFS for patients with tumors of squamous cell histology. Conclusion Pre-treatment in vitro cisplatin chemoresponse testing of cervix cancer biopsies was technically feasible and prognostic of RFS in patients treated with weekly cisplatin chemoRT.