Radical Radiotherapy in Head and Neck Squamous Cell Carcinoma: An Analysis of Prognostic and Therapeutic Factors

Correlation of alterations in the KEAP1/CUL3/NFE2L2 pathway with radiation failure in larynx squamous cell carcinoma

OBJECTIVES

Patients with laryngeal squamous cell carcinoma (LSCC) often fail radiation therapy (RT), when received as monotherapy or in combination with other treatment modalities. Mechanisms for RT failure are poorly understood. We hypothesized that tumors failing RT would have increased rates of somatic mutations in genes associated with radiation resistance, particularly in genes associated with the NFE2L2 oxidative stress pathway. Using targeted exome sequencing on pretreated LSCC tumors, we retrospectively compared somatic mutation profile with clinical data and response to treatment.

METHODS

Tumors were classified as either radiation-resistant (RR) or radiation-sensitive (RS). RR was defined as persistent or recurrent disease within 2 years of receiving full-dose RT. Early stage (ES) LSCC was defined as Stage I or II tumors without lymph node involvement. Eight genes associated with radiation resistance were prioritized for analysis. RT-qPCR was performed on five NFE2L2 pathway genes.

RESULTS

Twenty LSCC tumors were included and classified as either RR (n = 8) or RS (n = 12). No differences in individual rates of somatic mutations by genes associated with radiation resistance were identified. Higher rates of total mutational burden (TMB) and increased alterations associated with the NFE2L2 pathway was observed in RR vs RS tumors (P < .05). In an analysis of only ES-LSCC patients (RR, n = 3 and RS, n = 3), RR tumors had increased NFE2L2 somatic pathway mutations (P = .014) and increased NQO1 mRNA expression (P = .05).

CONCLUSION

Increased TMB and NFE2L2 pathway alterations were associated with radiation resistance in LSCC. NQO1 mRNA expression may serve as a biomarker for RT response in ES-LSCC.Level of Evidence: II1.

[Technical aspects and indications of extracranial stereotactic radiotherapy]

Extracranial stereotactic radiotherapy has developed considerably in recent years and is now an important part of the therapeutic alternatives to be offered to patients with cancer. It offers opportunities that have progressively led physicians to reconsider the therapeutic strategy, for example in the case of local recurrence in irradiated territory or oligometastatic disease. The literature on the subject is rich but, yet, there is no real consensus on therapeutic indications. This is largely due to the lack of prospective, randomized studies that have evaluated this technique with sufficient recoil. We propose a review of the literature on the technical aspects and indications of extracranial stereotactic radiotherapy.

Tissue and serum expression of TGM-3 may be prognostic marker in patients of oral squamous cell carcinoma undergoing chemo-radiotherapy

Radioresistance is one of the main determinants of treatment outcome in oral squamous cell carcinoma (OSCC), but its prediction is difficult. Several authors aimed to establish radioresistant OSCC cell lines to identify genes with altered expression in response to radioresistance. The development of OSCC is a multistep carcinogenic process that includes activation of several oncogenes and inactivation of tumour suppressor genes. TGM-3 is a tumour suppressor gene and contributes to carcinogenesis process. The aim of this study was to estimate serum and tissue expression of TGM-3 and its correlation with clinico-pathological factors and overall survival in patients of OSCC undergoing chemo-radiotherapy. Tissue expression was observed in formalin fixed tissue biopsies of 96 cases of OSCC and 32 healthy controls were subjected to immunohistochemistry (IHC) by using antibody against TGM-3 and serum level was estimated by ELISA method. mRNA expression was determined by using Real-Time PCR. Patients were followed for 2 year for chemo radiotherapy response. In OSCC, 76.70% cases and in controls 90.62% were positive for TGM-3 IHC expression. TGM-3 expression was cytoplasmic and nuclear staining expressed in keratinized layer, stratum granulosum and stratum spinosum in controls and tumour cells. Mean serum TGM-3 in pre chemo-radiotherapy OSCC cases were 1304.83±573.55, post chemo-radiotherapy samples were 1530.64±669.33 and controls were 1869.16±1377.36, but difference was significant in pre chemo-radiotherapy samples as compared to controls (p<0.018). This finding was also confirmed by real- time PCR analysis in which down regulation (-7.92 fold change) of TGM-3 in OSCC as compared to controls. TGM-3 expression was significantly associated with response to chemo-radiotherapy treatment (p<0.007) and overall survival (p<0.015). Patents having higher level of TGM-3 expression have good response to chemo-radiotherapy and also have better overall survival. TGM-3 may serve as a candidate biomarker for responsiveness to chemo-radiotherapy treatment in OSCC patients.

Magnetic Resonance Imaging-Detected Intracranial Extension in the T4 Classification Nasopharyngeal Carcinoma with Intensity-Modulated Radiotherapy

PURPOSE

This study was conducted is to identify the prognostic value and staging categories of magnetic resonance imaging (MRI)-detected intracranial extension in nasopharyngeal carcinoma (NPC) with intensity-modulated radiotherapy (IMRT) to determine whether it is necessary to subclassify the T4 classification NPC.

MATERIALS AND METHODS

A total of 335 nonmetastatic T4 classification NPC patients with MRI treated between March 2004 and June 2011 by radical IMRT were included. The T4 classification patients were subclassified into two grades (T4a, without intracranial extension vs. T4b, with intracranial extension) according to the site of invasion.

RESULTS

The frequency of intracranial extension was 40.9% (137 of 335 patients). Multivariate analysis identified subclassification (T4a vs. T4b) as an independent prognostic factor for local failure-free survival (p=0.049; hazard ratio [HR], 0.498) and overall survival (p=0.004; HR, 0.572); however, it had no effect on regional failure-free survival or distant failure-free survival (p > 0.050).

CONCLUSION

For patients with T4 classification NPC, those with MRI-detected intracranial extension are more likely to experience local failure and death after IMRT than patients without intracranial extension. According to the site of invasion, subclassification of T4 patients as T4a or T4b has prognostic value in NPC.

[Radioresistance parameters in head and neck cancers and methods to radiosensitize]

Head and neck cancers have been widely studied concerning their sensitivity to radiation therapy. Several parameters affect tumour response to radiation therapy. Some parameters are linked to the tumour. Large or invasive tumours, localization, such as oral cavity or adenopathy, are factors of radioresistance. Others parameters are linked to the patients themselves. Tobacco intoxication during radiotherapy and a low hemoglobin level contribute to radioresistance. More recently, a positive human papilloma virus (HPV) status has been reported to positively affect radiosensitivity. Finally, other parameters are related to tumour biology. Hypoxia, intrinsic radiosensitivity of tumour cells, tumour differentiation and repopulation (provided by Ki-67 index or EGFR level) are components of radiosensitivity. Currently, concurrent chemoradiotherapy is one of the gold standard treatments to overcome clinical outcome of locally advanced head and neck cancer. This combination increases locoregional control and survival. Taxane-based induction chemotherapy can also be an alternative. Another validated approach is the association of radiotherapy with cetuximab (EGFR targeting) but only one randomized study has been published. Fractionation modifications, especially hyperfractionation, have given positive results on both tumour control and survival. Strategies targeting hypoxia improve locoregional control but have less clinical impact.

Update report of T4 classification nasopharyngeal carcinoma after intensity-modulated radiotherapy: an analysis of survival and treatment toxicities

OBJECTIVE

To evaluate the long-term survival outcomes and toxicity of a larger series of patients with non-metastatic T4 classification nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiotherapy (IMRT).

MATERIALS AND METHODS

From March 2004 to June 2011, 335 non-metastatic T4 classification NPC patients treated by IMRT were analyzed retrospectively. Treatment induced toxicities were scored according to the Common Terminology Criteria for Adverse Events version 3.0.

RESULTS

With a median follow-up time of 53.6 months (range, 2.8-114.9 months), the 5-year local failure-free survival (LFFS), regional failure free survival (RFFS), distant failure-free survival (DFFS), and overall survival (OS) were 84.1%, 92.2%, 74.1%, and 63.0%, respectively. At their last follow-up visit, 118 patients (35.2%) had developed treatment failure. Distant metastasis was the major failure pattern after treatment. The most common toxicities were mainly in grade 1 or 2. Concurrent chemotherapy failed to improve survival rates for patients with T4 classification NPC.

CONCLUSION

The results of T4 classification NPC treated by IMRT were excellent, and distant metastasis was the most commonly failure pattern. Treatment-related toxicities were well tolerable. The role of concurrent chemotherapy for T4 classification NPC needs to be further investigated in the era of IMRT.

Definitive radiotherapy for cervical esophageal cancer

BACKGROUND

The role of contemporary radiotherapy (RT) has not yet been elucidated, mainly because of the low incidence of cervical esophageal cancer. The purpose of this study was to analyze the outcome in patients with cervical esophageal cancer treated with definitive RT.

METHODS

A total of 115 patients with cervical esophageal cancer treated with definitive RT during January 2001 through April 2012 in our center were analyzed. Eighty patients received RT alone and 35 patients received concurrent chemoradiotherapy with cisplatin administered either weekly (30 mg/m2) or every 3 weeks (80 mg/m2).

RESULTS

The median follow-up time was 17.1 months. For all patients, the overall 2-year local failure-free survival (LFFS), regional failure-free survival (RFFS), distant failure-free survival (DFFS), and overall survival (OS) rate was 68.3%, 83.3%, 75.7%, and 47.6%, respectively.

CONCLUSION

Definitive RT accomplished a satisfactory local control rate and contributed to organ preservation for patients with cervical esophageal cancer. 2015.

Expression of CXCL10 is associated with response to radiotherapy and overall survival in squamous cell carcinoma of the tongue

Five-year survival for patients with oral cancer has been disappointingly stable during the last decades, creating a demand for new biomarkers and treatment targets. Lately, much focus has been set on immunomodulation as a possible treatment or an adjuvant increasing sensitivity to conventional treatments. The objective of this study was to evaluate the prognostic importance of response to radiotherapy in tongue carcinoma patients as well as the expression of the CXC-chemokines in correlation to radiation response in the same group of tumours. Thirty-eight patients with tongue carcinoma that had received radiotherapy followed by surgery were included. The prognostic impact of pathological response to radiotherapy, N-status, T-stage, age and gender was evaluated using Cox's regression models, Kaplan-Meier survival curves and chi-square test. The expression of 23 CXC-chemokine ligands and their receptors were evaluated in all patients using microarray and qPCR and correlated with response to treatment using logistic regression. Pathological response to radiotherapy was independently associated to overall survival with a 2-year survival probability of 81% for patients showing a complete pathological response, while patients with a non-complete response only had a probability of 42% to survive for 2 years (p = 0.016). The expression of one CXC-chemokine, CXCL10, was significantly associated with response to radiotherapy and the group of patients with the highest CXCL10 expression responded, especially poorly (p = 0.01). CXCL10 is a potential marker for response to radiotherapy and overall survival in patients with squamous cell carcinoma of the tongue.

Long-term outcome and toxicity of hypofractionated stereotactic body radiotherapy as a boost treatment for head and neck cancer: the importance of boost volume assessment

Background

The aim of this study was to report the long-term clinical outcomes of patients who received stereotactic body radiotherapy (SBRT) as a boost treatment for head and neck cancer.

Materials and methods

Between March 2004 and July 2007, 26 patients with locally advanced, medically inoperable head and neck cancer or gross residual tumors in close proximity to critical structures following head and neck surgery were treated with SBRT as a boost treatment. All patients were initially treated with standard external beam radiotherapy (EBRT). SBRT boost was prescribed to the median 80% isodose line with a median dose of 21 (range 10–25) Gy in 2–5 (median, 5) fractions.

Results

The median follow-up after SBRT was 56 (range 27.6 − 80.2) months. The distribution of treatment sites in 26 patients was as follows: the nasopharynx, including the base of the skull in 10 (38.5%); nasal cavity or paranasal sinus in 8 (30.8%); periorbit in 4 (15.4%); tongue in 3 (11.5%); and oropharyngeal wall in 1 (3.8%). The median EBRT dose before SBRT was 50.4 Gy (range 39.6 − 70.2). The major response rate was 100% with 21 (80.8%) complete responses (CR). Severe (grade ≥ 3) late toxicities developed in 9 (34.6%) patients, and SBRT boost volume was a significant parameter predicting severe late complication.

Conclusions

The present study demonstrates that a modern SBRT boost is a highly efficient tool for local tumor control. However, we observed a high frequency of serious late complications. More optimized dose fractionation schedule and patient selection are required to achieve excellent local control without significant late morbidities in head and neck boost treatment.

Monte Carlo radiotherapy simulations of accelerated repopulation and reoxygenation for hypoxic head and neck cancer

OBJECTIVE

A temporal Monte Carlo tumour growth and radiotherapy effect model (HYP-RT) simulating hypoxia in head and neck cancer has been developed and used to analyse parameters influencing cell kill during conventionally fractionated radiotherapy. The model was designed to simulate individual cell division up to 10(8) cells, while incorporating radiobiological effects, including accelerated repopulation and reoxygenation during treatment.

METHOD

Reoxygenation of hypoxic tumours has been modelled using randomised increments of oxygen to tumour cells after each treatment fraction. The process of accelerated repopulation has been modelled by increasing the symmetrical stem cell division probability. Both phenomena were onset immediately or after a number of weeks of simulated treatment.

RESULTS

The extra dose required to control (total cell kill) hypoxic vs oxic tumours was 15-25% (8-20 Gy for 5 × 2 Gy per week) depending on the timing of accelerated repopulation onset. Reoxygenation of hypoxic tumours resulted in resensitisation and reduction in total dose required by approximately 10%, depending on the time of onset. When modelled simultaneously, accelerated repopulation and reoxygenation affected cell kill in hypoxic tumours in a similar manner to when the phenomena were modelled individually; however, the degree was altered, with non-additive results. Simulation results were in good agreement with standard linear quadratic theory; however, differed for more complex comparisons where hypoxia, reoxygenation as well as accelerated repopulation effects were considered.

CONCLUSION

Simulations have quantitatively confirmed the need for patient individualisation in radiotherapy for hypoxic head and neck tumours, and have shown the benefits of modelling complex and dynamic processes using Monte Carlo methods.

Squamous cell carcinoma of the hypopharynx: single-institution outcome analysis of a large cohort of patients treated with primary non-surgical approaches

INTRODUCTION

Hypopharyngeal cancers have extensive submucosal spread, high risk of nodal involvement and relatively high propensity of distant metastases. Contemporary paradigms for hypopharyngeal cancers aim to maximize loco-regional control while attempting to preserve laryngo-pharyngeal form and function.

AIMS

To retrospectively review outcome of large cohort of patients with hypopharyngeal cancers treated with curative intent radiotherapy with or without systemic chemotherapy in an academic tertiary referral centre.

MATERIAL AND METHODS

Medical records of patients with hypopharyngeal cancers treated with primary non-surgical approaches over a 15-year period were reviewed retrospectively. Loco-regional control (LRC) and disease-free survival (DFS) were considered as outcome measures.

RESULTS

Electronic search of database identified 501 patients with hypopharyngeal cancers treated with definitive radiotherapy. The median age was 55 years (range 20-87 years) and median radiotherapy dose 70 Gy (range 5.4-72 Gy). With a mean follow-up period of 22 months (median 12 months), the 3-year LRC and DFS was 47.1% and 40.9% respectively. Stage (T-stage, N-stage, overall stage grouping), and age influenced outcome significantly. The 3-year LRC for T1-T2 disease was 49.7% versus 43.1% for T3- T4 stage (p0.056). The 3-year DFS was 49.4% and 36.9% respectively (p0.014). The 3-year LRC and DFS for N0; N1; and N2-3 disease was 57.3% & 54.3%; 40.5% & 35.3%; and 33% & 27% respectively with highly significant p-values.

CONCLUSION

This is an outcome analysis of the largest cohort of patients with hypopharyngeal cancers managed with primary non-surgical approaches. Stage and age remain the most important determinants of outcome.

Efficient Monte Carlo modelling of individual tumour cell propagation for hypoxic head and neck cancer

A Monte Carlo tumour model has been developed to simulate tumour cell propagation for head and neck squamous cell carcinoma. The model aims to eventually provide a radiobiological tool for radiation oncology clinicians to plan patient treatment schedules based on properties of the individual tumour. The inclusion of an oxygen distribution amongst the tumour cells enables the model to incorporate hypoxia and other associated parameters, which affect tumour growth. The object oriented program FORTRAN 95 has been used to create the model algorithm, with Monte Carlo methods being employed to randomly assign many of the cell parameters from probability distributions. Hypoxia has been implemented through random assignment of partial oxygen pressure values to individual cells during tumour growth, based on in vivo Eppendorf probe experimental data. The accumulation of up to 10 million virtual tumour cells in 15 min of computer running time has been achieved. The stem cell percentage and the degree of hypoxia are the parameters which most influence the final tumour growth rate. For a tumour with a doubling time of 40 days, the final stem cell percentage is approximately 1% of the total cell population. The effect of hypoxia on the tumour growth rate is significant. Using a hypoxia induced cell quiescence limit which affects 50% of cells with and oxygen levels less than 1 mm Hg, the tumour doubling time increases to over 200 days and the time of tumour growth for a clinically detectable tumour (10(9) cells) increases from 3 to 8 years. A biologically plausible Monte Carlo model of hypoxic head and neck squamous cell carcinoma tumour growth has been developed for real time assessment of the effects of multiple biological parameters which impact upon the response of the individual patient to fractionated radiotherapy.

Clinical and biological factors affecting response to radiotherapy in patients with head and neck cancer: a review

OBJECTIVE

The main aim of this article was to review the clinical and biological factors that have been shown to influence the response of the head and neck squamous cell carcinoma (HNSCC) to primary radiotherapy and briefly discuss how some of these factors could be exploited to improve outcome.

DESIGN

Medline based search covering 1982-2006 to identify the HNSCC literature where the effect of clinical and biological factors on locoregional control and overall survival were investigated.

RESULTS

Clinical factors are routinely used in management decisions. Nevertheless, identically staged tumours receiving the same treatment may have different outcomes. Biological factors such as hypoxia, proliferation and radio-sensitivity play an important role in radiation response. However, these are not currently used in practise because tests that are clinically reliable and feasible are not available.

CONCLUSION

High-quality translational research will allow us to develop biological tests that can be used in routine clinical practise to tailor individual treatment, with the ability to improve patient outcome further by modifying the underlying tumour biology.