Radiotherapy and concurrent low-dose paclitaxel in locally advanced head and neck cancer

A facile approach for crosslinker free nano self assembly of protein for anti-tumor drug delivery: factors' optimization, characterization and in vitro evaluation

We report crosslinker free self assembly of bovine serum albumin (BSA) and a hydrophobic payload paclitaxel (PTX), into nanoparticles by harnessing the temperature driven unfolding of protein. To systematically study the effects of various factors responsible for the key attributes of the nanoparticles, a Resolution IV design was used. 20 formulations were made with pH, temperature, time of heating before and after addition of drug, stirring rate, protein concentration, and protein to drug ratio selected as independent variables. Particle size, encapsulation efficiency, yield and zeta potential were the response variables. Perturbation and Pareto charts were used to single out the important factors, while, mathematical equations and 3D surface charts have been used to describe the relationship between dependent and independent variables. Nanoparticles with size of 188-482 nm were observed with a highly negative zeta potential of -39.5 to -21.9. Nanoparticles obtained had decent encapsulation efficiency (72.5-87.9%) with effective yield (80.0-93.8%). Validation of the mathematical models with 4 runs indicated the good prognostic ability of Resolution IV design. Spectroscopic studies suggested the non-covalent complexation between BSA and PTX as the possible mechanism of self assembly due to irreversible conformational changes in protein. Transmission Electron Microscopy (TEM) revealed spherical nanoparticles with a porous network of PTX-BSA. X-ray Diffraction (XRD) showed amorphous nature of nanoparticles. PTX release from the nanoparticles was found to be controlled release and followed Peppas-Sahlin model. In vitro cytotoxicity of PTX-BSA nanoparticles was comparable to that of Taxol after 48 h treatment. These findings suggest heat driven BSA self assembly as a viable approach to formulate cytotoxic drug carrying nanoparticles which could be efficiently used in anti-cancer therapy.

Concurrent radiochemotherapy in locally-regionally advanced oropharyngeal squamous cell carcinoma: analysis of treatment results and prognostic factors

BACKGROUND

Concurrent radiochemotherapy is a recommended treatment option for patients with locally advanced squamous cell head and neck carcinomas with recent data showing the most significant absolute overall and event-free survival benefit achieved in patients with oropharyngeal tumours. The aim of this study was to analyse the results of three-dimensional conformal radiotherapy given with concomitant weekly cisplatin in patients with advanced oropharyngeal carcinoma and to identify prognostic factors influencing outcomes of this patients category.

METHODS

Sixty-five patients with stage III or IV squamous cell carcinoma of the oropharynx who underwent concurrent radiochemotherapy between January 2005 and December 2010 were retrospectively analyzed. All patients received radiotherapy to 70 Gy/35 fractions/2 Gy per fraction/5 fractions per week. Concurrent chemotherapy consisted of weekly cisplatin (30 mg/m(2)) started at the first day of radiotherapy.

RESULTS

Median age was 57 years (range, 36 to 69 years) and 59 (90.8%) patients were male. Complete composite response was achieved in 47 patients (72.3%). Local and/or regional recurrence was the most frequent treatment failure present in 19 out of 25 patients (76.0%). At a median follow-up of 14 months (range, 5 to 72 months), 2-year local relapse-free, regional relapse-free, locoregional relapse-free, disease-free, and overall survival rates were 48.8%, 57.8%, 41.7%, 33.2% and 49.7%, respectively.On multivariate analysis the only significant factor for inferior regional relapse-free survival was the advanced N stage (p = 0.048). Higher overall stage was independent prognostic factor for poorer local relapse-free survival, locoregional relapse-free survival and disease-free survival (p = 0.022, p = 0.003 and p = 0.003, respectively). Pre-treatment haemoglobin concentration was an independent prognostic factor for local relapse-free survival, regional relapse-free survival, locoregional relapse-free survival, disease-free survival, and overall survival (p = 0.002, p = 0.021, p = 0.001, p = 0.002 and p = 0.002, respectively).

CONCLUSIONS

Poor treatments results of this study suggested that introduction of intensity-modulated radiotherapy, use of induction chemotherapy followed by concurrent radiochemotherapy, accelerated radiotherapy regimens, and molecular targeted therapies could positively influence treatment outcomes. The incorporation of reversal of anaemia should be also expected to provide further improvement in locoregional control and survival in patients with advanced squamous cell carcinoma of the oropharynx.

Current issues in combined modality therapy in locally advanced head and neck cancer

Curative treatment for patients with locally advanced squamous cell carcinomas of the head and neck (SCCHN) is complex and multidisciplinary. Our understanding of the optimal management of this disease has improved over the years, incorporating refined surgical approaches, better radiotherapy delivery methods, and greater use of systemic therapies. Investigation into shifting epidemiology patterns has uncovered two biologically and clinically distinct diseases: the smoking-related entity and the increasingly common malignancy associated with human papilloma virus (HPV). Prognosis favors the latter, driving newer investigations into dose de-intensification to limit toxicities in patients with HPV-driven disease, and alternatively intensifying treatment to improve tumor control in those with a significant smoking history. In this review, I describe the most recent progress in the multi-modal integration of radiotherapy and chemoradiotherapy, and the role of targeted agents and personalized therapy, and conclude with a discussion of the relevance of these innovations with respect to HPV tumor status.

Concomitant chemoradiotherapy using low-dose weekly gemcitabine versus low-dose weekly paclitaxel in locally advanced head and neck squamous cell carcinoma: a phase III study

The objective of this study was to compare concomitant chemoradiotherapy based on weekly low-dose gemcitabine versus weekly low-dose paclitaxel in locally advanced head and neck squamous cell carcinoma. Previously, untreated patients with locally advanced squamous cell carcinoma of the head and neck were randomly assigned to one of the two concomitant chemoradiation regimens: (1) weekly gemcitabine at a dose of 100 mg/m(2) over 30 min 1-2 h before radiotherapy and (2) weekly paclitaxal at a dose of 20 mg/m(2) over 60 min 4-6 h before radiotherapy. The planned radiotherapy dose was 65 Gy over 6.5 weeks in 32 settings. Two hundred and sixteen patients were randomly divided into 2 groups: group A (110 patients) and group B (106 patients) who received concomitant weekly low-dose gemcitabine and low-dose paclitaxal, respectively, with the radiotherapy protocol. The hematological toxicity was generally mild. On the contrary, non-hematologic toxicities were severe. Grade III mucositis occurred in 36% in group A and in 24% in group B (P = 0.04). Moreover, grade III dermatitis were encountered in 24% in group A and 13% in group B (P = 0.049). Thirty-two (29%) of group A and 18(17%) of group B patients required enteral or parenteral feeding (P = 0.01). Sixteen (15%) of group A and 6 (6%) of group B required enteral or parenteral feeding that lasted for 6 months (P = 0.03). Regarding the late effect on swallowing, 8% of patients in group A and 2% of patients in group B required enteral or parenteral feeding for more than 6 months (P = 0.035). Response rates were 78 and 89% in groups A and B, respectively (P = 0.038). The 2-year progression-free survival figures were 54 and 64% of groups A and B, respectively; however, the 2-year overall survival figures were 56 and 67%, respectively. On the other hand, the 3-year progression-free survival figures were 39 and 48% for groups A and B, respectively, while the 3-year overall survival figures were 45 and 49%, respectively (P = 0.05). Both concomitant chemoradiotherapy regimens were easily given in the outpatient clinic. The regimen based on paclitaxel was significantly more tolerable and effective; however, the difference was not enormous.

The chemoradiation paradigm in head and neck cancer

In this article, we use the example of head and neck cancer to show how concurrent chemoradiotherapy is used to treat a cancer where locoregional control is central for treatment success. The advent of concurrent chemoradiation has significantly contributed to the curability of head and neck cancer, including locoregionally advanced disease. Preserving organ function and reducing toxic effects are increasingly the focus of clinical trials. We review the available chemoradiotherapy platforms used for head and neck cancer, with initial discussions focused on single-agent cytotoxic-based regimens. We then assess the literature on multiagent-based regimens and include a discussion of the integration of novel agents, such as EGFR inhibitors, and antiangiogenic drugs into treatment platforms. Although single-agent cisplatin-based chemoradiotherapy is still widely used as a standard therapy, we propose that evidence increasingly shows that multiagent-based chemoradiotherapy, and EGFR-inhibitor-based treatments, offer distinct advantages. We provide guidance for clinicians based on current clinical trial evidence on how to choose appropriate treatment platforms for their patients.

Taxanes in head and neck cancer

Paclitaxel and docetaxel are cytotoxic agents that act on the microtubule system and cause cell death. They are active in patients with squamous cell carcinoma of the head and neck region. They can be combined with other cytotoxic agents and radiotherapy with acceptable toxicity. This article reviews of both docetaxel and paclitaxel data in this patient population. Taxanes do not yet have a a license for use in the standard treatment of patients with head and neck cancer in Europe.

Taxanes in the treatment of head and neck cancer

PURPOSE OF REVIEW

This review presents new data on the role of paclitaxel and docetaxel in the management of squamous cell carcinoma of the head and neck. Recently both agents have been tested in squamous cell carcinoma of the head and neck in combination with other chemotherapeutic agents, targeted drugs, and radiotherapy in in-vitro experiments and in the clinic as first-line treatment of patients with metastatic/recurrent and locally advanced squamous cell carcinoma of the head and neck.

RECENT FINDINGS

The combination of taxanes with standard or accelerated radiotherapy is feasible and induction chemotherapy followed by chemoradiation is active and feasible without excessive toxicity in patients with locally advanced squamous cell carcinoma of the head and neck. The use of low-dose fractionated radiotherapy shows promising in-vitro and clinical results and is further explored.

SUMMARY

Both docetaxel and paclitaxel can be combined with chemotherapeutic agents and radiotherapy, but phase III studies are needed to prove the superiority of these approaches compared to standard treatment. The final results of the combination study of cisplatin and 5-fluorouracil with or without docetaxel may change the standard chemotherapeutic regimen for induction chemotherapy in patients with locally advanced squamous cell carcinoma of the head and neck.

A comparative analysis of low-dose metronomic cyclophosphamide reveals absent or low-grade toxicity on tissues highly sensitive to the toxic effects of maximum tolerated dose regimens

The survival benefits of traditional maximum tolerated dose (MTD) cytotoxic therapy have been modest for the treatment of most types of metastatic malignancy and, moreover, often come with increased acute and chronic toxicity. Recent studies have demonstrated that the frequent administration of comparatively low doses of cytotoxic agents, with no extended breaks [low-dose metronomic (LDM) chemotherapy], may not only be at least as efficient as MTD therapy but also less toxic. This coincides with an apparent selectivity for "activated" endothelial cells of the tumor vasculature. However, the impact of LDM chemotherapy on the most sensitive target cell populations normally affected by MTD therapy (i.e., bone marrow progenitors, gut mucosa, and hair follicle cells) has not been analyzed in experimental detail. Therefore, we compared effects of LDM and MTD cyclophosphamide (CTX) on bone marrow and gut mucosa. Furthermore, we studied the potential impact of LDM CTX on angiogenesis in the context of wound healing and evidence of organ toxicity. We show absent or moderate hematologic and intestinal toxicity of LDM as opposed to MTD CTX. Of note was the finding of sustained lymphopenia, which is not unexpected given the use of CTX as immunosuppressive drug. There was no negative impact on wound healing or evidence of organ toxicity. LDM offers clear safety advantages over conventional MTD chemotherapy and therefore would appear to be ideal for long-term combination therapy with targeted antiangiogenic drugs.