A comparison of cisplatin and fluorouracil alone or with docetaxel in squamous cell carcinoma of the head and neck

Radiosensitization of TPGS-emulsified docetaxel-loaded poly(lactic-co-glycolic acid) nanoparticles in CNE-1 and A549 cells

Docetaxel is among the most effective radiosensitizers. It is widely used as radiosensitizer in many tumors, including head and neck carcinoma. Nevertheless, poor solubility and severe hypersensitivity limit its clinical use and its therapeutic effect remains to be improved. In this study, docetaxel-loaded polymeric nanoparticles were prepared by nanoprecipitation method to be new radiosensitizer with lower side effects and higher efficacy. The physiochemical characteristics of the nanoparticles were studied. Two human tumor cell lines which are resistant to radiotherapy were used in this research. We have compared the radioenhancement efficacy of docetaxel-loaded nanoparticles with docetaxel in A549 and CNE-1 cells. Compared with docetaxel, radiosensitization of docetaxel-loaded nanoparticles was improved significantly (sensitization enhancement ratio in A549 increased 1.24-fold to 1.68-fold when the radiation was applied 2 h after the drug, p < 0.01, sensitization enhancement ratio in CNE-1 increased 1.32-fold to 1.61-fold, p < 0.05). We explored the mechanisms for the radiosensitization efficiency and the difference between docetaxel and docetaxel-loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles. The improved radiosensitization efficacy was associated with enhanced G2/M arrest, promoted apoptosis and the role of D-alpha-tocopheryl polyethylene glycol 1000 succinate which will enhance the cell uptake and inhibit the multiple drug resistance. Moreover, the radiosensitization efficacy of docetaxel-loaded nanoparticles was more prominent than docetaxel. In conclusion, tocopheryl polyethylene glycol 1000 succinate-emulsified docetaxel-loaded PLGA nanoparticles were more efficacious and fewer adverse effects were observed than with the commercial docetaxel formulation. Thus, PLGA nanoparticles hold promise as a radiosensitizing agent.

Chemotherapy with PLGA microspheres containing docetaxel decreases angiogenesis in human hepatoma xenograft

To investigate the antiangiogenic effect of sustained-release poly (lactic-co-glycolic acid) microspheres containing docetaxel (PMCD) in human hepatoma xenograft. PMCD were prepared by solvent evaporation method with an encapsulation efficiency of 98.7% and a release period of about 3 weeks in vitro. PMCD were intratumorally injected once for mice bearing a human hepatocellular carcinoma. On day 21 post-treatment, the inhibition rate of tumor growth was 72.7% in the high-dose group, indicating a significant antitumor activity. Meanwhile, excellent antiangiogenic effect was observed based on the contrast-enhanced ultrasonography as well as microvessel density determination. Additionally, the real-time fluorescence quantitative PCR revealed that the expressions of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and angiopoietin-2 (Ang2) genes were down-regulated significantly. Interstitial chemotherapy using PMCD was highly effective and safe for the treatment of the human hepatoma xenograft and that decreasing angiogenesis could be one of the most important mechanisms involved in the antitumor activity.

Can synchronous chemotherapy be added to accelerated hypofractionated radiotherapy in patients with base of tongue cancer?

AIM

To evaluate the tolerability of synchronous chemotherapy and accelerated hypofractionated radiotherapy in patients with locally advanced squamous cell carcinoma of the base of the tongue.

MATERIALS AND METHODS

Between 1999 and 2004, 43 patients with stage II-IV squamous cell carcinoma of the base of the tongue were treated with a combined modality of radiotherapy (prescribed 55 Gy in 20 fractions), synchronous chemotherapy and in some cases surgical neck dissection. End points were acute and late toxicity, 3 year locoregional control, overall survival, cancer-specific survival and compliance.

RESULTS

The median follow-up for surviving patients was 3.9 years. All patients completed radiotherapy and 30% received neoadjuvant chemotherapy. The median time for the completion of treatment was 27 days (range 25-36). Overall, only 42% completed the prescribed synchronous chemotherapy. However, compliance increased to 60% in patients who did not receive neoadjuvant chemotherapy. Grade 3 mucositis developed in 90% of patients. Prolonged grade 3 mucositis (>4 weeks) was seen in 24/43 (56%) and none developed grade 4 mucositis. There were no toxic deaths. Feeding tube dependency at 1 year was 14%. The 3 year locoregional control, overall survival and cancer-specific survival were 70, 60 and 60%, respectively. Clinical T staging was most significantly associated with poor overall survival, cancer-specific survival and local control. Distant metastases occurred in 6/43 patients (14%), 5/6 without locoregional recurrence.

CONCLUSION

The addition of synchronous chemotherapy to accelerated hypofractionated radiotherapy consistently led to grade 3 mucositis. Tumour control rates compare well with published outcomes. Higher mucosal toxicity and lower synchronous chemotherapy compliance compared with other series may suggest that this approach is at the limit of patient tolerability. However, the tumour site investigated and the choice of synchronous chemotherapy agent may also be important. Compliance may be improved using intensity-modulated radiotherapy and agents that do not enhance mucosal toxicity. Longer fractionation will probably increase compliance with chemotherapy, particularly when induction is used before synchronous treatment.