Metastatic HER-2-positive salivary gland carcinoma treated with trastuzumab and a taxane: a series of six patients

Metastatic salivary gland carcinoma is a rare malignancy. A subset of these tumors overexpresses the human epidermal growth factor receptor 2 (HER-2), which is considered a poor prognostic marker. Targeted therapy with the monoclonal antibody trastuzumab can be a treatment option in these patients. We describe six cases of metastatic salivary gland carcinoma treated with trastuzumab in combination with a taxane. Three of these patients had salivary duct cancer, two had mucoepidermoid carcinoma and one patient was treated for acinic cell carcinoma. The therapy was well tolerated. We observed five partial responses and a median progression free survival of 10.8 months, which compares favorably with the reported outcome of combination chemotherapy. One patient achieved a complete and durable remission. When HER-2 and androgen receptor were co-expressed, trastuzumab-based treatment appeared to be more active than androgen deprivation in our experience.

Towards 3D printed multifunctional immobilization for proton therapy: Initial materials characterization

PURPOSE

3D printing technology is investigated for the purpose of patient immobilization during proton therapy. It potentially enables a merge of patient immobilization, bolus range shifting, and other functions into one single patient-specific structure. In this first step, a set of 3D printed materials is characterized in detail, in terms of structural and radiological properties, elemental composition, directional dependence, and structural changes induced by radiation damage. These data will serve as inputs for the design of 3D printed immobilization structure prototypes.

METHODS

Using four different 3D printing techniques, in total eight materials were subjected to testing. Samples with a nominal dimension of 20 × 20 × 80 mm³ were 3D printed. The geometrical printing accuracy of each test sample was measured with a dial gage. To assess the mechanical response of the samples, standardized compression tests were performed to determine the Young's modulus. To investigate the effect of radiation on the mechanical response, the mechanical tests were performed both prior and after the administration of clinically relevant dose levels (70 Gy), multiplied with a safety factor of 1.4. Dual energy computed tomography (DECT) methods were used to calculate the relative electron density to water ρ_e, the effective atomic number Z_eff, and the proton stopping power ratio (SPR) to water SPR. In order to validate the DECT based calculation of radiological properties, beam measurements were performed on the 3D printed samples as well. Photon irradiations were performed to measure the photon linear attenuation coefficients, while proton irradiations were performed to measure the proton range shift of the samples. The directional dependence of these properties was investigated by performing the irradiations for different orientations of the samples.

RESULTS

The printed test objects showed reduced geometric printing accuracy for 2 materials (deviation > 0.25 mm). Compression tests yielded Young's moduli ranging from 0.6 to 2940 MPa. No deterioration in the mechanical response was observed after exposure of the samples to 100 Gy in a therapeutic MV photon beam. The DECT-based characterization yielded Z_eff ranging from 5.91 to 10.43. The SPR and ρ_e both ranged from 0.6 to 1.22. The measured photon attenuation coefficients at clinical energies scaled linearly with ρ_e. Good agreement was seen between the DECT estimated SPR and the measured range shift, except for the higher Z_eff. As opposed to the photon attenuation, the proton range shifting appeared to be printing orientation dependent for certain materials.

CONCLUSIONS

In this study, the first step toward 3D printed, multifunctional immobilization was performed, by going through a candidate clinical workflow for the first time: from the material printing to DECT characterization with a verification through beam measurements. Besides a proof of concept for beam modification, the mechanical response of printed materials was also investigated to assess their capabilities for positioning functionality. For the studied set of printing techniques and materials, a wide variety of mechanical and radiological properties can be selected from for the intended purpose. Moreover the elaborated hybrid DECT methods aid in performing in-house quality assurance of 3D printed components, as these methods enable the estimation of the radiological properties relevant for use in radiation therapy.

CT-based follow-up following radiotherapy or radiochemotherapy for locally advanced head and neck cancer; outcome and development of a prognostic model for regional control

OBJECTIVE

The purpose of this study was to make a prognostic model for regional relapse in head and neck cancer using clinical and CT parameters.

METHODS

183 patients with lymph node-positive head and neck cancer were treated between 2002 and 2012 with radiotherapy or concurrent chemoradiotherapy. CT studies pre- and post-treatment were reviewed for lymph node size and the presence of necrosis, extracapsular spread (ECS) and calcifications. For every patient, correlations with 3-year regional control (RC), metastasis-free survival (MFS), disease-free survival (DFS) and overall survival (OS) were made.

RESULTS

3-year outcome rates were as follows: local control of 84%, RC of 80%, MFS of 74%, DFS of 61% and OS of 63%. Pre-treatment nodal size and the presence of necrosis were associated with a poorer outcome. This was also the case for post-treatment lymph node size, the presence of necrosis and ECS. We developed a CT-based prognostic model for RC with an area under the curve of 0.78 (95% confidence interval 0.63; 0.85).

CONCLUSION

We reached a good outcome in our patient cohort using a CT-based follow-up approach. A CT-based model was developed, which can aid in predicting RC. Advances in knowledge: A prognostic model is proposed, which can aid in predicting RC and the necessity for post-radiotherapy neck dissection using clinical parameters and parameters derived from the post-treatment CT study. This is the first article to propose a prognostic model for regional relapse in head and neck cancer based on these parameters.

Radiotherapy induced dermatitis is a strong predictor for late fibrosis in head and neck cancer. The development of a predictive model for late fibrosis

PURPOSE

To determine if the severity of radiodermatitis at the end of radio(chemo)therapy (R(C)T) for head and neck cancer (HNC) is a predictive factor for late fibrosis of the neck and to find a model to predict neck fibrosis grade⩾2 (fibrosis RTOG_2-4) at 6months following R(C)T for HNC.

MATERIAL/METHODS

161 patients were prospectively included. We correlated radiodermatitis at the end of RCT, age, sex, T/N stage, tumor site, concomitant chemotherapy, upfront neck dissection, neo-adjuvant chemotherapy, accelerated RT, smoking, alcohol consumption, HPV status and the dose prescribed to the elective neck with fibrosis RTOG_2-4 6months after the end of treatment.

RESULTS

Radiodermatitis at the end of R(C)T ⩾grade 3 proved to be associated with the incidence of fibrosis RTOG_2-4 at 6months (p<0.01). Furthermore, upfront neck dissection (p<0.01), increasing N stage (p<0.01) and tumor site (p=0.02) are significantly associated in univariate analysis with fibrosis RTOG_2-4 at 6months of follow-up. Upfront neck dissection and radiodermatitis grade⩾3 at the end of R(C)T were identified by our multivariate model. Additionally, increasing N stage was selected as an independent predictor variable. The AUC for this model was 0.92.

CONCLUSION

A model for the prediction of fibrosis RTOG_2-4 following R(C)T for head and neck cancer is presented with an AUC of 0.92. Interestingly, radiodermatitis grade⩾3 at the end of R(C)T is associated with RTOG_2-4 fibrosis at 6months.

Reduction of the dose of radiotherapy to the elective neck in head and neck squamous cell carcinoma; a randomized clinical trial. Effect on late toxicity and tumor control

BACKGROUND AND PURPOSE

A multi-center prospective randomized clinical trial has been performed investigating whether a reduction of the dose to the elective nodal sites in head and neck cancer delivered by intensity modulated radiotherapy (IMRT) would result in a reduction of late side effects without compromising tumor control.

MATERIALS AND METHODS

Two hundred patients were included. The prescription dose to the elective nodal volumes was a normalized iso-effective dose in 2Gy fractions (NID_2Gy) of 50Gy in the standard arm and of 40Gy in the experimental arm. Late toxicity was scored at 6, 12, 18 and 24months using the RTOG scoring system.

RESULTS

We observed a trend toward less dysphagia at 6months in the experimental arm, however this was not confirmed after longitudinal analysis. Regarding moderate salivary gland toxicity we observed lower incidence of salivary gland toxicity ⩾grade 1, at 6 (p=0.01) and 18months (p=0.03). After two years of follow up, we did not observe significant differences in estimated local failure rate (14.1% in the 40Gy arm vs 14.4% in the 50Gy arm), estimated regional failure rate (13.0% vs 5.5% in the 40 and the 50Gy arm respectively), estimated metastatic recurrence (13.4% vs 18.5% in the 40 and the 50Gy arm respectively), estimated disease-free survival (57.9% vs 65.3% in the 40 and the 50Gy arm respectively) nor estimated overall survival (72.0% vs 73.2% in the 40 and the 50Gy arm respectively).

CONCLUSIONS

In our study population there was no statistically significant difference regarding survival and estimated recurrence rates between both arms of this study. We found a trend toward less dysphagia at 6months (however not significant after longitudinal analysis) and found a significant reduction of any salivary gland toxicity at 6 and 18months in the 40Gy arm.

Differences in human papillomavirus-positive and -negative head and neck cancers in Belgium: an 8-year retrospective, comparative study

OBJECTIVES

This study investigated the prevalence of human papillomavirus (HPV)-related oropharyngeal squamous cell carcinoma (OPSCC) and compared patient profiles and outcomes between HPV-positive and HPV-negative groups.

STUDY DESIGN

This retrospective study included all patients treated for OPSCC in the University Hospitals of Leuven between 2004 and 2012. Paraffin-embedded tumor tissue was available for all patients. Patient characteristics, treatment, and follow-up data were retrieved from medical files. HPV status was determined by immunohistochemical staining for the p16 epitope.

RESULTS

Among 94 patients, the prevalence of HPV-positive OPSCC was 22.34%. Compared with HPV-negative tumors, HPV-positive tumors were correlated with less smoking and alcohol consumption, tonsillar sublocalization (P < .05), and younger age. HPV-positive OPSCC was associated with better overall survival (62.2%) compared with HPV-negative OPSCC (42.5%; P = .0588).

CONCLUSIONS

Among patients with OPSCC, those with HPV exhibited profiles different from those without HPV. HPV-positive OPSCC was associated with better overall survival compared with HPV-negative OPSCC. HPV-positive OPSCC prevalence increased over time.

HPV Positive Head and Neck Cancers: Molecular Pathogenesis and Evolving Treatment Strategies

Head and neck squamous cell carcinoma (HNSCC) is a highly heterogeneous disease that is the result of tobacco and/or alcohol abuse or infection with high-risk Human papillomaviruses. Despite the fact that HPV positive HNSCC cancers form a distinct clinical entity with better treatment outcome, all HNSCC are currently treated uniformly with the same treatment modality. At present, biologic basis of these different outcomes and their therapeutic influence are areas of intense investigation. In this review, we will summarize the molecular basis for this different outcome, novel treatment opportunities and possible biomarkers for HPV positive HNSCC. In particular, the focus will be on several molecular targeted strategies that can improve the chemoradiation response by influencing DNA repair mechanisms.

Effect of p16 Status on the Quality-of-Life Experience During Chemoradiation for Locally Advanced Oropharyngeal Cancer: A Substudy of Randomized Trial Trans-Tasman Radiation Oncology Group (TROG) 02.02 (HeadSTART)

PURPOSE

Human papillomavirus-associated oropharyngeal cancer (OPC) has a favorable prognosis. Current research de-escalates treatment, aiming to improve quality of life (QOL). Understanding the QOL experience with current standard treatment (chemoradiation therapy) provides context for emerging data. We report the impact of p16 status on QOL for patients with stage III or IV OPC undergoing chemoradiation therapy in an international phase 3 trial (TROG 02.02 [HeadSTART]).

METHODS AND MATERIALS

A subgroup analysis by p16 status was conducted in patients with OPC treated in a phase 3 randomized trial. The study subset with OPC and known p16 status was mainly from Australasia, Western Europe, and North America. Of 861 participants, 200 had OPC, known p16 status, and baseline QOL data; 82 were p16 negative and 118 were p16 positive. Radiation therapy (70 Gy over a period of 7 weeks) was given concurrently with 3 cycles of either cisplatin (100 mg/m²) or cisplatin (75 mg/m²) plus tirapazamine. QOL was measured with the Functional Assessment of Cancer Therapy-Head and Neck (FACT-H&N) questionnaire at baseline and 2, 6, 12, 23, and 38 months. Because no significant difference in QOL score was observed between arms, results by p16 status are reported with arms combined.

RESULTS

The p16-positive patients were younger, had a better Eastern Cooperative Oncology Group performance status, and were less often current smokers. Our primary hypothesis that the change in FACT-H&N score from baseline to 6 months would be more favorable in the p16-positive cohort was not met (p16 positive, -6.3; p16 negative, -1.8; P=.14). The mean baseline FACT-H&N score was statistically and clinically significantly better in p16-positive patients (111 vs 102, P<.001); at 2 months, scores declined in both groups but more dramatically for p16-positive patients. By 12 months, p16-positive patients again had superior scores. A higher baseline FACT-H&N score and p16-positive status were independent predictors of overall survival.

CONCLUSIONS

Patients with p16-positive OPC exhibited better baseline QOL but showed a more dramatic QOL drop with concurrent chemoradiation. Given the favorable prognosis of p16-positive OPC, efforts to reduce the QOL burden of treatment are warranted.

Dependence of Gold Nanoparticle Radiosensitization on Functionalizing Layer Thickness

Gold nanoparticles functionalized with polyethylene glycol of different chain lengths are used to determine the influence of the capping layer thickness on the radiosensitizing effect of the particles. The size variations in organic coating, built up with polyethylene glycol polymers of molecular weight 1-20 kDa, allow an evaluation of the decrease in dose enhancement percentages caused by the gold nanoparticles at different radial distances from their surface. With localized eradication of malignant cells as a primary focus, radiosensitization is most effective after internalization in the nucleus. For this reason, we performed controlled radiation experiments, with doses up to 20 Gy and particle diameters in a range of 5-30 nm, and studied the relaxation pattern of supercoiled DNA. Subsequent gel electrophoresis of the suspensions was performed to evaluate the molecular damage and consecutively quantify the gold nanoparticle sensitization. In conclusion, on average up to 58.4% of the radiosensitizing efficiency was lost when the radial dimensions of the functionalizing layer were increased from 4.1 to 15.3 nm. These results serve as an experimental supplement for biophysical simulations and demonstrate the influence of an important parameter in the development of nanomaterials for targeted therapies in cancer radiotherapy.

The role of stem cells in the prevention and treatment of radiation-induced xerostomia in patients with head and neck cancer

Xerostomia is an important complication following radiotherapy (RT) for head and neck cancer. Current treatment approaches are insufficient and can only temporarily relieve symptoms. New insights into the physiopathology of radiation‐induced xerostomia might help us in this regard. This review discusses the current knowledge of salivary gland stem cells in radiation‐induced xerostomia and their value in the prevention and treatment of this complication. Salivary gland stem cell transplantation, bone marrow‐derived cell mobilization, molecular regulation of parotid stem cells, stem cell sparing RT, and adaptive RT are promising techniques that are discussed in this study.

The incidence of hypothyroidism after radiotherapy for head and neck cancer

The incidence of hypothyroidism after radiotherapy for head and neck cancer.

OBJECTIVES

To identify the incidence of radiation-induced hypothyroidism (HT) after head and neck radiotherapy.Furthermore, we wanted to correlate patient and treatment characteristics with the incidence of HT in order to identify predictive factors for radiation-induced HT.

METHODOLOGY

We examined the values of thyrotropin, i.e., the thyroid-stimulating hormone (TSH), in head and neck cancer patients who received a combination treatment of radiotherapy and chemotherapy between 2005 and 2012. HT was defined as having a TSH value of > 10 mIU/L or whenever the patient started to take substitution therapy after treatment. We correlated the radiotherapy mean dose to the thyroid gland (Dmean), the pretreatment volume of the thyroid gland, sex, age, type of concomitant treatment, tumour localization, and T and N classification with the incidence of HT.

RESULTS

We were able to obtain data from 72 patients. From these 72 patients, 48 (66%) had a normal thyroid function and 25 (34%) had developed HT. The mean follow-up for these patients was 55 months (range: 21 to 103 months). Out of the 25 patients with HT, 8 (32%) were diagnosed within the first year of follow-up. Increasing Dmean is a significant risk factor for developing HT. Increasing thyroid volume, on the other hand, was correlated with less HT in our patient cohort.

CONCLUSIONS

In our study, the incidence of HT is 34%. We also noticed that HT can even develop shortly after treatment. Patients with a higher Dmean to the thyroid gland and lower pretreatment thyroid gland volumes are more at risk.

Advances in Radiotherapy for Head and Neck Cancer

Over the last few decades, significant improvements have been made in the radiotherapy (RT) treatment of head and neck malignancies. The progressive introduction of intensity-modulated RT and the use of multimodality imaging for target volume and organs at risk delineation, together with the use of altered fractionation regimens and concomitant administration of chemotherapy or targeted agents, have accompanied efficacy improvements in RT. Altogether, such improvements have translated into improvement in locoregional control and overall survival probability, with a decrease in the long-term adverse effects of RT and an improvement in quality of life. Further progress in the treatment of head and neck malignancies may come from a better integration of molecular imaging to identify tumor subvolumes that may require additional radiation doses (ie, dose painting) and from treatment adaptation tracing changes in patient anatomy during treatment. Proton therapy generates even more exquisite dose distribution in some patients, thus potentially further improving patient outcomes. However, the clinical benefit of these approaches, although promising, for patients with head and neck cancer need to be demonstrated in prospective randomized studies. In this context, our article will review some of these advances, with special emphasis on target volume and organ-at-risk delineation, use of molecular imaging for tumor delineation, dose painting for dose escalation, dose adaptation throughout treatment, and potential benefit of proton therapy.

Long-term follow-up of 123 patients with adenocarcinoma of the sinonasal tract treated with endoscopic resection and postoperative radiation therapy

BACKGROUND

Most series about endoscopic resection of adenocarcinomas of the sinonasal tract present outcome data from a small heterogeneous group of patients with a relatively short follow-up period and a wide variety of histological subtypes and treatment protocols. This relatively large study with a very homogeneous study population updates our experience with a stable treatment protocol looking at survival rates, surgical technique, and prognostic factors.

METHODS

We conducted a retrospective analysis of the medical records of 123 patients with adenocarcinoma of the intestinal type primarily treated with endoscopic resection and postoperative radiotherapy (RT) in a single tertiary referral center during the period 1992 to 2010.

RESULTS

Mean follow-up was 66 months and median follow-up was 54 months. Mean and median follow-up of the subgroup of patients alive at the end of follow-up was 74 months and 61 months, respectively. At 5-years of follow-up, overall survival (OS), disease-specific survival (DSS), and recurrence-free survival (RFS) were 68%, 82%, and 62% respectively. At 10-year follow-up, these numbers were 51%, 74%, and 45%, respectively. Prognostic factors for treatment outcome are predominantly local recurrence, development of distant metastasis, T classification, histopathological classification, and the center where the first surgery was performed.

CONCLUSION

This large study of sinonasal adenocarcinoma primarily treated with endoscopic resection and RT confirms that this approach results in good oncologic and functional outcome.

Panitumumab plus radiotherapy versus chemoradiotherapy in patients with unresected, locally advanced squamous-cell carcinoma of the head and neck (CONCERT-2): a randomised, controlled, open-label phase 2 trial

BACKGROUND

We aimed to compare panitumumab, a fully human monoclonal antibody against EGFR, plus radiotherapy with chemoradiotherapy in patients with unresected, locally advanced squamous-cell carcinoma of the head and neck.

METHODS

In this international, open-label, randomised, controlled, phase 2 trial, we recruited patients with locally advanced squamous-cell carcinoma of the head and neck from 22 sites in eight countries worldwide. Patients aged 18 years and older with stage III, IVa, or IVb, previously untreated, measurable (≥ 10 mm for at least one dimension), locally advanced squamous-cell carcinoma of the head and neck (non-nasopharygeal) and an Eastern Cooperative Oncology Group performance status of 0-1 were randomly assigned (2:3) by an independent vendor to open-label chemoradiotherapy (two cycles of cisplatin 100 mg/m(2) during radiotherapy) or to radiotherapy plus panitumumab (three cycles of panitumumab 9 mg/kg every 3 weeks administered with radiotherapy) using a stratified randomisation with a block size of five. All patients received 70-72 Gy to gross tumour and 54 Gy to areas of subclinical disease with accelerated fractionation radiotherapy. The primary endpoint was local-regional control at 2 years, analysed in all randomly assigned patients who received at least one dose of their assigned protocol-specific treatment (chemotherapy, radiation, or panitumumab). The trial is closed and this is the final analysis. This study is registered with ClinicalTrials.gov, number NCT00547157.

FINDINGS

Between Nov 30, 2007, and Nov 16, 2009, 152 patients were enrolled, and 151 received treatment (61 in the chemoradiotherapy group and 90 in the radiotherapy plus panitumumab group). Local-regional control at 2 years was 61% (95% CI 47-72) in the chemoradiotherapy group and 51% (40-62) in the radiotherapy plus panitumumab group. The most frequent grade 3-4 adverse events were mucosal inflammation (25 [40%] of 62 patients in the chemoradiotherapy group vs 37 [42%] of 89 patients in the radiotherapy plus panitumumab group), dysphagia (20 [32%] vs 36 [40%]), and radiation skin injury (seven [11%] vs 21 [24%]). Serious adverse events were reported in 25 (40%) of 62 patients in the chemoradiotherapy group and in 30 (34%) of 89 patients in the radiotherapy plus panitumumab group.

INTERPRETATION

Panitumumab cannot replace cisplatin in the combined treatment with radiotherapy for unresected stage III-IVb squamous-cell carcinoma of the head and neck, and the role of EGFR inhibition in locally advanced squamous-cell carcinoma of the head and neck needs to be reassessed.

FUNDING

Amgen.

HPV-positive head and neck tumours, a distinct clinical entity

A worldwide rise in the incidence of oropharyngeal squamous cell cancer has been recorded over the past decade. This rise has been attributed to an increase in oncogenic human papilloma virus (HPV) infections. The biology of HPV-positive oropharyngeal cancer is distinct; it includes p53 degradation, retinoblastoma pathway inactivation, and p16 upregulation. The best method for detecting HPV in tumour material is controversial; both in-situ hybridisation and PCR are commonly used. However, p16 can serve as a potential surrogate marker, and therefore, p16 immunohistochemistry is widely used in clinical practice. Compared to HPV-negative cancers, HPV-positive oropharyngeal cancer appears to be more responsive to chemotherapy and radiotherapy. Thus, p16 can serve as a prognostic marker for enhanced overall survival and disease-free survival. In this review, we aimed to highlight the current understanding of the epidemiology, biology, detection, and management of HPV-related oropharyngeal head and neck squamous cell carcinoma.

Elevated carcinoembryonic antigen tumour marker caused by head and neck cancer: a case report and literature study

Carcinoembryonic antigen is a tumour marker commonly increased in gastrointestinal and pulmonary cancers. We report a case of a 46-year-old man with a mucoepidermoid carcinoma of the base of tongue with an elevated and traceable serum carcinoembryonic antigen level. This antigen proved to be a valuable marker in the treatment follow-up. When a raised carcinoembryonic antigen level is found, salivary gland malignancies should be taken into the differential diagnosis and clinical examination of the head and neck region should not be overlooked.

Quality assurance for the EORTC 22071-26071 study: dummy run prospective analysis

Purpose

The phase III 22071–26071 trial was designed to evaluate the addition of panitumumab to adjuvant chemotherapy plus intensity modulated radiotherapy (IMRT) in locally advanced resected squamous cell head and neck cancer. We report the results of the dummy run (DR) performed to detect deviations from protocol guidelines.

Methods and Materials

DR datasets consisting of target volumes, organs at risk (OAR) and treatment plans were digitally uploaded, then compared with reference contours and protocol guidelines by six central reviewers. Summary statistics and analyses of potential correlations between delineations and plan characteristics were performed.

Results

Of 23 datasets, 20 (87.0%) GTVs were evaluated as acceptable/borderline, along with 13 (56.5%) CTVs and 10 (43.5%) PTVs. All PTV dose requirements were met by 73.9% of cases. Dose constraints were met for 65.2-100% of mandatory OARs. Statistically significant correlations were observed between the subjective acceptability of contours and the ability to meet dose constraints for all OARs (p ≤ 0.01) except for the parotids and spinal cord. Ipsilateral parotid doses correlated significantly with CTV and PTV volumes (p ≤ 0.05).

Conclusions

The observed wide variations in treatment planning, despite strict guidelines, confirms the complexity of development and quality assurance of IMRT-based multicentre studies for head and neck cancer.

Electronic supplementary material

The online version of this article (doi:10.1186/s13014-014-0248-9) contains supplementary material, which is available to authorized users.

Clinical and dosimetric evaluation of RapidArc versus standard sliding window IMRT in the treatment of head and neck cancer

BACKGROUND

Several planning studies have already proven the substantial dosimetric advantages of RapidArc (RA) over standard intensity-modulated radiotherapy. We retrospectively compared RapidArc and standard sliding window IMRT (swIMRT) in locally advanced head and neck cancer, looking both at dosimetrics as well as toxicity and outcome.

METHODS

CT datasets of 78 patients treated with swIMRT and 79 patients treated with RA were included. To compare the resulting dose distributions, the dose-volume parameters were evaluated for the planning target volumes (PTVs), clinical target volumes (CTVs), and organs at risk (OARs), and the number of MU were calculated. Acute toxicity was assessed by the Common Toxicity Criteria version 3.0.

RESULTS

PTV coverage with the 95% isodose was slightly better for RA. Dose distribution has proven to be significantly more homogenous with RA and led to a reduction of 62% in MU with better OAR sparing. As for toxicity, more grade 3 mucositis and dysphagia was observed for swIMRT, though we observed more grade 3 dermatitis for RA.

CONCLUSION

In our retrospective analysis, RA had better target coverage and better sparing of the OAR. Overall, the grade of acute toxicity was lower for RA than for swIMRT for the same types of tumor locations, except for the grade of dermatitis.

FLT1 kinase is a mediator of radioresistance and survival in head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) is the fifth most common malignancy worldwide, responsible for approximately half a million new cases every year. The treatment of this disease is challenging and characterised by high rates of therapy failure and toxicity, stressing the need for new innovative treatment strategies.

MATERIAL AND METHODS

In this study we performed a shRNAmir-based screen on HNSCC cells with the aim to identify tyrosine kinases that are mediating radiotherapy resistance.

RESULTS

The receptor tyrosine kinase FLT1 (VEGFR1) was identified as an important driver of cell survival and radioresistance. We show that FLT1 is phosphorylated in HNSCC cells, and document autocrine production of FLT1 ligands VEGFA and VEGFB, leading to receptor activation. Immunohistochemistry on HNSCC patient samples demonstrated FLT1 and VEGFA to be uniformly expressed. Interestingly, FLT1 was selectively overexpressed in tumour tissue as compared to non-cancerous epithelium. Remarkably, we found only membrane permeable FLT1 kinase inhibitors to be effective, which was in agreement with the intracellular localisation of FLT1.

DISCUSSION AND CONCLUSION

Taken together, we document expression of FLT1 in HNSCC and demonstrate this kinase to modulate radioresistance and cancer cell survival. Given the fact that FLT1 kinase is selectively upregulated in tumour tissue and that its kinase function seems expendable for normal life and development, this kinase holds great promise as a new potential therapeutic target.

Integrating pretreatment diffusion weighted MRI into a multivariable prognostic model for head and neck squamous cell carcinoma

INTRODUCTION

In head and neck squamous cell carcinoma (HNSCC) the ability to anticipate an individual patient's outcome is very valuable. With this study we wanted to assess the prognostic value of pretreatment apparent diffusion coefficient (ADC) in a large patient population and integrate it into a multivariable prognostic model.

METHODS

From 2004 to 2010 175 patients with pathology proven HNSCC were included in this study. All patients underwent a pretreatment MRI with diffusion weighted imaging (DWI) using six b-values. For each tumor, three ADC values were calculated using different b-value combinations: ADC(low) (b 0-50-100 s/mm(2)), ADChigh (b 500-750-1000 s/mm(2)) and ADC(avg) (all b-values). The clinical and radiological variables included: tumor and nodal volume, tumor location and age. Disease recurrence was analyzed using competing risk regression. A prognostic model for disease recurrence was developed, and internal validation was performed using bootstrapping and by dividing patients in three equal sized groups based on prognosis.

RESULTS

One hundred and sixty-one patients were eligible for analysis. Median follow-up was 50 months (range 4-86). A total of 67 patients experienced disease recurrence during follow-up (42%). ADC(high) was a prognostic factor for disease recurrence (adjusted hazard ratio: 1.14 per 10(-4) mm(2)/s, 95% CI 1.04-1.25). Harrell's c-index of the multivariable prognostic model was 0.62 (95% CI 0.56-0.70) after internal validation. The validated 3-year disease recurrence rates for the groups with worst, intermediate, and best prognosis were 56%, 33% and 31% respectively.

CONCLUSION

Pretreatment ADC value derived from high b-values is an independent prognostic factor in HNSCC and increases the performance of a multivariable prognostic model in addition to known clinical and radiological variables. Integration of other biomarkers and external validation is necessary to ensure its clinical applicability.

p16INK4a impairs homologous recombination-mediated DNA repair in human papillomavirus-positive head and neck tumors

The p16INK4a protein is a principal cyclin-dependent kinase inhibitor that decelerates the cell cycle. Abnormally high levels of p16INK4a are commonly observed in human papillomavirus (HPV)-positive head and neck squamous cell carcinomas (HNSCC). We and others found that p16INK4a overexpression is associated with improved therapy response and survival of patients with HNSCC treated with radiotherapy. However, the functional role of p16INK4a in HNSCC remains unexplored. Our results implicate p16INK4a in regulation of homologous recombination-mediated DNA damage response independently from its role in control of the cell cycle. We found that expression of p16INK4a dramatically affects radiation sensitivity of HNSCC cells. p16INK4a overexpression impairs the recruitment of RAD51 to the site of DNA damage in HPV-positive cells by downregulating of cyclin D1 protein expression. Consistent with the in vitro findings, immunostaining of HNSCC patient samples revealed that high levels p16INK4a expression significantly correlated with decreased cyclin D1 expression. In summary, these findings reveal an unexpected function of p16INK4a in homologous recombination-mediated DNA repair response and imply p16INK4a status as an independent marker to predict response of patients with HNSCC to radiotherapy.

Noncutaneous head and neck cancer in solid organ transplant patients: single center experience

BACKGROUND

We investigated the incidence and survival of non-cutaneous head and neck cancer (HNC) after solid organ transplantation and identified prognostic factors impacting the outcome after treatment.

METHODS

A retrospective analysis of patients who underwent solid organ transplantation in our institution between 1987 and 2012.

RESULTS

Of 5255 organ transplant patients, 48 recipients (0.9%) developed HNC in the posttransplant follow-up period. Liver transplant recipients showed the highest risk. Median follow-up of cancer patients was 46.7 months (range 2.9-256.2 months). Three-year overall survival and disease free survival (DFS) were 70% and 53%. Locoregional control was 67% and 48% at 3 and 5 years, respectively. Smoking and initial AJCC stage were two significant prognostic factors influencing DFS.

CONCLUSIONS

Non-cutaneous HNC is rare in transplant recipients, but slightly more common after liver transplantation. Outcome after treatment is poor with locoregional recurrence being the main problem. Screening of high risk groups might be relevant.

HPV-related oropharyngeal cancers in Flanders (Belgium): a multicenter study

INTRODUCTION

Human papilloma virus (HPV) was recently reported to play a major role in oropharyngeal carcinoma. Large geographical differences in the disease prevalence have been described. Until now, no data have been reported for Flanders (Belgium).

METHODS

A multicenter cooperative study was undertaken at the radiation-oncology departments of Flemish universities. Tumor blocks from patients diagnosed with oropharyngeal carcinoma between 2000 and 2010 were tested for HPV at a single center. Patients' characteristics, treatments, and follow-up data were recorded from medical files. Age standardized incidence rates of oropharyngeal carcinoma were collected from the Belgian Cancer Registry.

RESULTS AND CONCLUSIONS

The incidence of oropharyngeal carcinoma has increased in males and females. Tissues were collected from 264 patients and the HPV status could be defined in 249 of them. The prevalence of HPV(+) oropharyngeal carcinoma was 24.78% (19.93-30.36%). In our cohort, HPV(+) tumors occurred in patients with more advanced tumor stages (p < 0.05), who smoked less (p < 0.05), consumed less alcohol (p < 0.05), had a tonsillar/base of tongue sublocalization (p < 0.05), and were older (p < 0.05). After radiotherapy, locoregional control and disease free survival were significantly better for patients with HPV(+) status (p < 0.05) in univariate analysis. HPV status remained a strong predictor of better locoregional control after multivariate analysis. We found that concurrent chemotherapy had an equal benefit for locoregional control in both HPV(+) and HPV(-) patients.

Redefining the target early during treatment. Can we visualize regional differences within the target volume using sequential diffusion weighted MRI?

PURPOSE

In head and neck cancer, diffusion weighted MRI (DWI) can predict response early during treatment. Treatment-induced changes and DWI-specific artifacts hinder an accurate registration between apparent diffusion coefficient (ADC) maps. The aim of the study was to develop a registration tool which calculates and visualizes regional changes in ADC.

METHODS

Twenty patients with stage IV HNC treated with primary radiotherapy received an MRI including DWI before and early during treatment. Markers were manually placed at anatomical landmarks on the different modalities at both time points. A registration method, consisting of a fully automatic rigid and nonrigid registration and two semi-automatic thin-plate spline (TPS) warps was developed and applied to the image sets. After each registration step the mean registration errors were calculated and ΔADC was compared between good and poor responders.

RESULTS

Adding the TPS warps significantly reduced the registration error (in mm, 6.3 ± 6.2 vs 3.2 ± 3.3 mm, p<0.001). After the marker based registration the median ΔADC in poor responders was significantly lower than in good responders (7% vs. 21%; p<0.001).

CONCLUSIONS

This registration method allowed for a significant reduction of the mean registration error. Furthermore the voxel-wise calculation of the ΔADC early during radiotherapy allowed for a visualization of the regional differences of ΔADC within the tumor.

Reduction of the dose to the elective neck in head and neck squamous cell carcinoma, a randomized clinical trial using intensity modulated radiotherapy (IMRT). Dosimetrical analysis and effect on acute toxicity

BACKGROUND AND PURPOSE

A randomized trial was initiated to investigate whether a reduction of the dose to the elective nodal sites and the swallowing apparatus delivered by IMRT would result in a reduction of acute and late side effects without compromising tumor control. The aim of this paper is to report on dosimetrical analysis and acute toxicity.

MATERIALS & METHODS

Two-hundred patients were randomized. In the standard arm, elective nodal volumes (PTVelect) were irradiated up to an equivalent dose of 50Gy. In the experimental arm an equivalent dose of 40Gy was prescribed to the PTVelect. The dose to the swallowing apparatus was kept as low as possible without compromising therapeutic PTV (PTVther) coverage.

RESULTS

No significant difference was seen between both arms concerning PTVther coverage. The median D95 of the PTVelect was significantly lower in the experimental arm (39.5 vs 49.8Gy; p<0.001). Concerning the organs at risk, the dose to swallowing structures and spinal cord was significantly reduced. There was no significant difference in acute toxicity. Three months after radiotherapy there was significantly less grade ⩾3 dysphagia in the experimental arm (2% vs 11%; p=0.03). With a median follow-up of 6months no significant differences were observed in locoregional control, disease free survival or overall survival.

CONCLUSIONS

Using IMRT we were able to significantly reduce the dose to the PTVelect and several organs at risk without compromising PTVther coverage. This resulted in a significant reduction of severe dysphagia 3months after radiotherapy. Further follow-up is necessary to investigate whether these observations translate into a benefit on late treatment related dysphagia without affecting treatment outcome.

A dose escalation study with intensity modulated radiation therapy (IMRT) in T2N0, T2N1, T3N0 squamous cell carcinomas (SCC) of the oropharynx, larynx and hypopharynx using a simultaneous integrated boost (SIB) approach

BACKGROUND

The simultaneous integrated boost (SIB) technique with dose per fraction slightly higher than 2Gy offers the advantages of shortening the treatment time and increasing the biologically equivalent dose to the tumor. This study was designed to evaluate the feasibility of a dose-escalating radiotherapy treatment by using a SIB-IMRT approach in patients with early and moderately advanced head and neck cancers.

MATERIALS AND METHODS

Fifty-seven consecutive patients with pharyngo-laryngeal T2N0 or T2N1, or laryngeal T3N0 SCC were included. The therapeutic PTVs were treated according to three consecutive dose levels i.e., 69 Gy in 30 fractions of 2.3 Gy (dose level I), 72 Gy in 30 fractions of 2.4 Gy (dose level II) or 75 Gy in 30 fractions of 2.5 Gy (dose level III). The prophylactic PTVs received a dose of 55.5 Gy delivered in 30 fractions of 1.85 Gy. The primary endpoint of the study was acute toxicity assessed during treatment and during the first 3 months following the completion of radiotherapy. The secondary endpoints included loco-regional control, disease-free survival, overall survival and late toxicity at 2 years of follow-up. The study design allowed patients to be enrolled in the second dose level group if no more than 10% of grade 4 acute toxicity was observed on the first dose level group within 3 months after the completion of IMRT, and so on for the third level group.

RESULTS

Forty-four men and 13 women were included in the trial. The majority of them presented with oropharyngeal cancer (53%) and laryngeal cancer (33%). Only 3 patients developed grade 4 acute mucositis during treatment, one in each dose level. Thirty-two patients (56%) experienced grade 3 toxicity, mostly dermatitis and mucositis, without any significant difference between the groups. Late grade 1 and 2 xerostomia was seen in 53% and 33% of patients, respectively. Transient grade 4 late toxicity was observed in 16% of all patients and was equally distributed among the groups. The 2-year loco-regional control was 82% for all 3 groups (79% dose level I, 88% dose level II, 79% dose level III). The 2-year overall survival was 89% for dose level I and II, and 95% for dose level III.

CONCLUSIONS

This dose escalation SIB-IMRT protocol was safe and effective as the sole treatment of early and moderately advanced SCC of head and neck. No toxicity difference was observed between the groups.

RapidArc, SmartArc and TomoHD compared with classical step and shoot and sliding window intensity modulated radiotherapy in an oropharyngeal cancer treatment plan comparison

BACKGROUND

Radiotherapy techniques have evolved rapidly over the last decade with the introduction of Intensity Modulated RadioTherapy (IMRT) in different forms. It is not clear which of the IMRT techniques is superior in the treatment of head and neck cancer patients in terms of coverage of the planning target volumes (PTVs), sparing the organs at risk (OARs), dose to the normal tissue, number of monitor units needed and delivery time.The present paper aims to compare Step and Shoot (SS) IMRT, Sliding Window (SW) IMRT, RapidArc (RA) planned with Eclipse, Elekta VMAT planned with SmartArc (SA) and helical TomoHD™ (HT).

METHODS

Target volumes and organs at risk (OARs) of five patients with oropharyngeal cancer were delineated on contrast enhanced CT-scans, then treatment plans were generated on five different IMRT systems. In 32 fractions, 69.12 Gy and 56 Gy were planned to the therapeutic and prophylactic PTVs, respectively. For the PTVs and 26 OARs ICRU 83 reporting guidelines were followed. Differences in the studied parameters between treatment planning systems were analysed using repeated measures ANOVA.

RESULTS

Mean Homogeneity Index of PTV(therapeutic) is better with HT(.06) followed by SA(.08), RA(.10), SW(.10) and SS(.11). PTV(prophylactic) is most homogeneous with RA. Parotid glands prescribed mean doses are only obtained by SA and HT, 20.6 Gy and 21.7 Gy for the contralateral and 25.6 Gy and 24.1 Gy for the ipsilateral, against 25.6 Gy and 32.0 Gy for RA, 26.4 Gy and 34.6 Gy for SW, and 28.2 Gy and 34.0 Gy for SS. RA uses the least monitor units, HT the most. Treatment times are 3.05 min for RA, and 5.9 min for SA and HT.

CONCLUSIONS

In the treatment of oropharyngeal cancer, we consider rotational IMRT techniques preferable to fixed gantry techniques due to faster fraction delivery and better sparing of OARs without a higher integral dose. TomoHD gives most homogeneous target coverage with more sparing of spinal cord, brainstem, parotids and the lower swallowing apparatus than most of the other systems. Between RA and SA, SA gives a more homogeneous PTV(therapeutic) while sparing the parotids more, but the delivery of RA is twice as fast with less overdose to the PTV(elective).