Validation of a 15-gene hypoxia classifier in head and neck cancer for prospective use in clinical trials.

BACKGROUND: In head and neck squamous cell carcinomas (HNSCC) hypoxic radioresistance can be reduced by use of the hypoxic modifier nimorazole, as shown in the DAHANCA 5 trial. Recently, a 15-gene hypoxia classifier has shown predictive impact for the effect of nimorazole by identifying 'more' and 'less' hypoxic tumors in the DAHANCA 5 cohort. A prospective multicentre EORTC-1219 study is initiated, where nimorazole and prospective use of the classifier as a predictor is tested in relation to the most recent accelerated chemoradiotherapy treatment. Validation of the gene expression classification procedures is described here. MATERIAL AND METHODS: Formalin-fixed paraffin-embedded (FFPE) tumor material from three recent HNSCC cohorts [DAHANCA 18 (n = 96), 24 (n = 40), and IAEA Hypo (n = 55)] was used to establish and validate procedures for prospective classification of patients. Repeatability was tested for the different steps in the gene expression analysis, and reproducibility was tested with xenograft tumors (FaDuDD, UTSCC33), where gene expression in complementary sections was compared after fixation and embedding locally and at international institutions, respectively. Intra-tumor heterogeneity was addressed by classifying biopsy samples from HNSCC tumors, where 2-4 biopsies from each tumor was accessible. RESULTS: Procedures were successfully established for individual classification of HNSCC patients in retrospective and prospective cohorts. Measurements of gene expression levels were reproducible between different international institutions. CONCLUSION: Technical validation of the 15-gene hypoxia classifier demonstrated that it is suitable for implementation in prospective clinical trials.

Compliance and toxicity of the hypoxic radiosensitizer nimorazole in the treatment of patients with head and neck squamous cell carcinoma (HNSCC).

PURPOSE: To evaluate the compliance and toxicity of the hypoxic radiosensitizer nimorazole in head and neck cancer patients. METHODS: A retrospective study of patients with head and neck squamous cell carcinoma (HNSCC), treated in Denmark between 1990 and 2013. All patients treated with radical radiotherapy (± chemotherapy) [66-70 Gy; 33-35 fractions; 2 Gy/fraction; 5-6 fractions/week] concomitant with the hypoxic radiosensitizer nimorazole. Nimorazole was administered as oral tablets in doses of approximately 1.2 g/m(2) body surface area in connection with the first of each daily radiation treatment. A second daily dose of 1 g was given in connection with the second radiotherapy fraction in the accelerated fractionation regimen. The compliance was estimated as the percentage of the initially prescribed dose, which was received by each patient. The main side effects were recorded. RESULTS: A total of 1049 patients were investigated. The tolerance to nimorazole was fair: 58% of patients received the full prescribed total dose. Nausea and vomiting were the major complaints: among the 260 patients with dose reductions due to known side effects, (87%) were due to nausea/vomiting. All side effects ceased when treatment was interrupted, and neither severe nor long lasting side effects were observed. Female patients were significantly more likely to have dose reduction (OR 2.02; 95% CI 1.50-2.70), and nausea/vomiting. Patients aged more than 70 years were significantly more likely to have dose reduction. Patients who received less than 1100 mg/m(2) were significantly less likely to have dose reduction (OR 0.58; CI 0.44-0.78), and nausea/vomiting, compared to those who received 1100-1300 mg/m(2). The tolerance was also less in the group of patients received accelerated chemoradiotherapy (OR 1.70; CI 1.20-2.50) with more association with nausea/vomiting (OR 2.09; CI 1.40-3.10). CONCLUSION: The compliance to nimorazole is fair, with tolerable acute, but neither persistent nor late, toxicity. It can be administered with chemotherapy and different radiotherapy fractionation schedules.