Number of patients potentially eligible for proton therapy

A group of Swedish radiation oncologists and hospital physicists have estimated the number of patients in Sweden suitable for proton beam therapy in a facility where one of the principal aims is to facilitate randomized and other studies in which the advantage of protons can be shown and the magnitude of the differences compared with optimally administered conventional radiation treatment, also including intensity-modulated radiation therapy (IMRT) and brachytherapy, can be shown. The estimations have been based on current statistics of tumour incidence in Sweden, number of patients potentially eligible for radiation treatment, scientific support from clinical trials and model dose planning studies and knowledge of the dose-response relations of different tumours together with information on normal tissue complication rates. In Sweden, it is assessed that between 2200 and 2500 patients annually are eligible for proton beam therapy, and that for these patients the potential therapeutic benefit is so great as to justify the additional expense of proton therapy. This constitutes between 14-15% of all irradiated patients annually.

[Role of radiotherapy in the XXI century]

In the last twenty years the extraordinary rise of information technology has made possible key technological developments at the service of precision in radiotherapy treatments: in obtaining three-dimensional images, in systems planning and in radiation units. Thus in less than two decades there progress has been made from radiotherapy in two dimensions (RT 2D) to 3D conformal radiotherapy (3DCRT) and to modulation of intensity modulated radiotherapy for maximum conformation (IMRT). High precision in radiation delivery adjusts the prescribed dosage to the white volume, better preserving the adjacent healthy tissue. It is thus possible to aspire to improving the therapeutic index in two respects, either reducing late toxicity when this is a problem of sufficient scale, or scaling the dosage in the white volume in order to increase tumour control without provoking further toxicity. A final component in reaching the present state of radiotherapy is of capital importance: the guided image which makes it possible to direct the beams of radiation, adapting them to the possible changes of position of the white volume before or during treatment.

Predicting response to radiotherapy: evolutions and revolutions

PURPOSE

To review the many changes which have occurred in the past decades in the field of predicting outcome after radiotherapy from biological characteristics of the tumour or normal tissue. This review will also describe the present state of the art and emerging trends for the future.

CONCLUSIONS

From using explanted cells, glass electrodes, exogenous proliferation and hypoxia tracers, and others, there has been a move towards monitoring expression and mutation of genes. Initially this was possible for just one or a few genes, but methods are now available which allow genome-wide monitoring at either the DNA or RNA level. The potential advantage of this evolution is not only to predict but also to understand potential causes of failure, allowing more rational and effective interventions. Comparative genomic hybridisation, mRNA expression profiling, microRNA profiling and promoter methylation profiling have all shown promise in finding signatures correlating with outcome, including after treatment involving radiotherapy. Expected trends for the future are: more signatures relevant to radiotherapy will be discovered; signatures will be refined and reduced to their essentials, such that genome-wide screening will give way to tailored signatures, quantifiable by routine non-array technology; more focus will be on assays predicting which pathway-specific radiosensitising drugs will be effective (exploiting tumour weaknesses); more signatures will be subjected to validation in randomised trials; and proteomics, DNA sequencing and imaging methods will play progressively increasing roles.

[Modern radiation therapy]

For decades, radiation therapy has constituted one of the main forms of therapy for cancer, and has undergone rapid technical development. New techniques in radiotherapy make it possible to treat a tumor with larger doses than before, while at the same time reducing damage to healthy tissues. The development in imaging techniques has allowed a more precise delimitation of tumors and monitoring of the efficacy of therapy. Three-dimensional tumor delimitation and dose calculation have long been the standard in radiation therapy. Four-dimensional and functional imaging in defining the target area for radiation therapy is becoming part of routine radiotherapy.

[Trends in breast cancer treatment in the elderly at a breast cancer outpatient clinic: guidelines followed better]

OBJECTIVE

To investigate the treatment of resectable breast cancer in elderly patients at Alkmaar Medical Centre, Alkmaar, the Netherlands, before and after the introduction of a multidisciplinary breast cancer consultation (MDC) with the breast cancer team in February 2006.

DESIGN

Retrospective.

METHOD

The treatment of patients aged 70 and over with newly diagnosed stage I and II resectable breast cancer was monitored during the period 2002-2007.

RESULTS

A total of 84% of the 232 studied patients were treated surgically. Adjuvant treatment with radiotherapy, hormone therapy and chemotherapy was given to 88, 91 and 5 patients, respectively. The percentage of patients who underwent first-line surgery decreased significantly, mainly because fewer patients aged 80 or over received surgery. The number of patients given radiotherapy in accordance with guidelines increased, while for hormonal therapy the number remained more or less the same. Recording of decisions that involved deviation from treatment guidelines improved in the study period.

CONCLUSION

In 2002-2007, the breast cancer team became more aware of treatment guidelines and deviations from guidelines were better accounted for. In the elderly, the guidelines for adjuvant radiotherapy were followed better, but there was a remarkable decrease in primary surgical treatment of patients, particularly in patients aged 80 and over. Comorbidity and patients' preferences played an important role in this.

New technologies in radiation therapy: ensuring patient safety, radiation safety and regulatory issues in radiation oncology

New technologies such as intensity modulated and image guided radiation therapy, computer controlled linear accelerators, record and verify systems, electronic charts, and digital imaging have revolutionized radiation therapy over the past 10-15 y. Quality assurance (QA) as historically practiced and as recommended in reports such as American Association of Physicists in Medicine Task Groups 40 and 53 needs to be updated to address the increasing complexity and computerization of radiotherapy equipment, and the increased quantity of data defining a treatment plan and treatment delivery. While new technology has reduced the probability of many types of medical events, seeing new types of errors caused by improper use of new technology, communication failures between computers, corrupted or erroneous computer data files, and "software bugs" are now being seen. The increased use of computed tomography, magnetic resonance, and positron emission tomography imaging has become routine for many types of radiotherapy treatment planning, and QA for imaging modalities is beyond the expertise of most radiotherapy physicists. Errors in radiotherapy rarely result solely from hardware failures. More commonly they are a combination of computer and human errors. The increased use of radiosurgery, hypofractionation, more complex intensity modulated treatment plans, image guided radiation therapy, and increasing financial pressures to treat more patients in less time will continue to fuel this reliance on high technology and complex computer software. Clinical practitioners and regulatory agencies are beginning to realize that QA for new technologies is a major challenge and poses dangers different in nature than what are historically familiar.

Preventing neurocognitive late effects in childhood cancer survivors

Neurocognitive late effects are common sequelae of cancer in children, especially in those who have undergone treatment for brain tumors or in those receiving prophylactic cranial radiation therapy to treat leukemia. Neurocognitive morbidity in attention, executive functioning, processing speed, working memory, and memory frequently occurs and contributes to declines in intellectual and academic abilities. Oncologists are faced with the challenge of using the most effective, often the most intense, therapy to achieve the primary goal of medical success, balanced with the desire to prevent adverse late effects. Not all children with similar diagnoses and treatment have identical neurocognitive outcomes; some do very poorly and some do well. Attention now turns to the reliable prediction of risk for poor outcomes and then, using risk-adapted therapy, to preserve neurocognitive function. Prevention of late effects through rehabilitative strategies, continuation of school, and pharmacotherapy will be explored.

Tracheobronchial amyloidosis: utilization of radiotherapy as a treatment modality

Tracheobronchial amyloidosis (TBA) is a rare disease. No general consensus exists with regard to its optimal treatment, resulting in a variety of modalities used to manage this condition. In this article, we present a case of TBA treated with external beam radiation therapy with encouraging results. A brief literature review of this rare ailment is also included.

[Main results of research reported by the Center's Department of Innovation in Radiotherapy]

The efficacy of multimodality conservative treatment for prostate and bladder cancer and cervical carcinoma was improved due to integration of such modem modalities as intra-arterial chemotherapy, local hyperthermia and hyperglycemia and combination of local and systemic radiomodifiers. Our methods use criteria of actual survival and are intended to raise it.

[External radiation therapy for thyroid disease]

The external beam irradiation plays a very important role in the treatment of some thyroid diseases, such as primary cancers (papillary, follicular, medullary and anaplastic), malignant lymphoma and bone metastasis. The treatment policies, the irradiation techniques and the treatment results of these diseases are described from our experiences and the literature. The recent improvements of irradiation techniques are also explained.

Outcome in adult low-grade glioma: the impact of prognostic factors and treatment

Low-grade gliomas (LGGs) represent a vexing clinical problem. Some patients present with readily controllable seizures and will enjoy years of freedom from tumor progression without intervention, whereas others progress rapidly with eventual neurologic decompensation and death. Both radiation and chemotherapy are helpful to many patients, but the optimal timing and sequencing of these therapies remain unknown. Recent studies have informed our understanding of clinical, histologic, and molecular prognostic factors and help provide guidance as to which patients require early intervention and when observation is feasible or warranted. We review contemporary knowledge regarding prognostic factors, our current evidence-based understanding of the roles and timing of radiation and chemotherapy, and ongoing clinical trials that will further elucidate management of LGGs.

Salvage whole brain radiotherapy for recurrent or refractory primary CNS lymphoma

BACKGROUND

High-dose methotrexate (MTX) and whole brain radiation therapy (WBRT) prolong survival in primary CNS lymphoma (PCNSL) patients but have been associated with delayed neurotoxicity. Consequently, patients are often treated with chemotherapy alone, and WBRT is deferred until relapse.

METHODS

We performed a retrospective study to evaluate the safety and efficacy of salvage WBRT. Radiographic response, survival, and late neurotoxicity were assessed as the main endpoints.

RESULTS

Forty-eight patients received salvage WBRT for PCNSL progression or recurrence. After WBRT, 58% achieved a complete radiographic response, 21% achieved a partial response, 6% had stable disease, and 15% progressed. The median survival from initiation of WBRT was 16 months, and 54% were alive 1 year after WBRT. The median time to PCNSL progression was 10 months; 15 patients (31%) had no subsequent disease recurrence after WBRT. Age younger than 60 years and complete response to WBRT were associated with better outcome. Treatment-related neurotoxicity was observed in 22% of patients. Patients older than 60 years and those treated less than 6 months from MTX therapy were at increased risk for development of neurotoxicity.

CONCLUSIONS

Salvage whole brain radiation therapy (WBRT) is effective for recurrent and refractory primary CNS lymphoma. Reserving WBRT until tumor recurrence is a reasonable strategy to minimize or delay the risk of treatment-related neurotoxicity.

Absorption characteristics of protons and photons in tissue

This presentation reviews the radiation quality of protons and other energetic ion beams, where radiation quality refers to those relevant physical properties other than the dose of the different types of radiations that can contribute to differences in the absorption characteristics in various tissues and the corresponding clinical outcomes. Prior to initiation of clinical trials with protons, neutrons, pions, and heavy ions, it was generally believed that such particles might have a therapeutic advantage resulting from their greater relative biological effectiveness (RBE). Potential clinical advantages resulting from a greater biological effectiveness, however, have generally been overshadowed during the last three decades by improved controls or reduced complications resulting primarily from the better dose delivery and localization that was possible with these heavier particles in conjunction with improved imaging. The successes both in delivery and in the clinical responses with protons and other light ions resulting from improved dose localization have arguably led the way in stereotactic radiosurgery, intensity modulated radiation therapy, and tomotherapy, stimulating improved methods with conventional radiations as well. Protons or light ions differ significantly in comparison with photon or electron beams in how they interact with the tissue atoms and molecules, and in how they transfer energy to those tissues. Microscopically, the heavier particles tend to travel in straight lines and produce long tracks with the energy concentrated closer to the track of the primary particle, while photons or electrons tend to scatter more easily and produce a more uniform distribution of energy transfers. Because they are hadrons, i.e., nuclear particles, protons and ions are more likely to produce long-range nuclear secondaries with higher masses. This higher concentration of energy associated with the heavier particle beams and the more massive secondaries results in differences in dose localization, clinically and microscopically, and therefore potential differences in short-term and long-term chemical and biological processes. Protons tend to have the least differences in clinical response in comparison with photons and electrons, the radiations used conventionally in therapy, but biological differences have been observed for these particles; it behooves us, therefore, to understand these different mechanisms if we are to take full advantage of their benefits. This article reviews the physical properties of these different particles in terms of microdosimetric distributions of energy deposition in order to compare protons with photons and heavy ions.

The diagnosis and management of malignant phaeochromocytoma and paraganglioma

Malignant phaeochromocytomas are rare tumours accounting for ~10% of all phaeochromocytomas; the prevalence of malignancy among paragangliomas is higher, especially those associated with succinate dehydrogenase subunit B gene mutations. Although a subset of these tumours has metastatic disease at initial presentation, a significant number develops metastases during follow-up after excision of an apparently benign tumour. Clinical, biochemical and histological features cannot reliably distinguish malignant from benign tumours. Although a number of recently introduced molecular markers have been explored, their clinical significance remains to be elucidated from further studies. Several imaging modalities have been utilised for the diagnosis and staging of these tumours. Functional imaging using radiolabelled metaiodobenzylguanidine (MIBG) and more recently, (18)F-fluorodopamine and (18)F-fluorodopa positron emission tomography offer substantial sensitivity and specificity to correctly detect metastatic phaeochromocytoma and paraganglioma and helps identify patients suitable for treatment with radiopharmaceuticals. The 5-year mortality rate of patients with malignant phaeochromocytomas and paragangliomas greater than 50% indicates that there is considerable room for the improvement of currently available therapies. The main therapeutic target is tumour reduction and control of symptoms of excessive catecholamine secretion. Currently, the best adjunctive therapy to surgery is treatment with radiopharmaceuticals using (131)I-MIBG; however, this is very rarely curative. Chemotherapy has been used for metastatic disease with only a partial and mainly palliative effect. The role of other forms of radionuclide treatment either alone or in combination with chemotherapy is currently evolving. Ongoing microarray studies may provide novel intracellular pathways of importance for proliferation/cell cycle control, and lead to the development of novel pharmacological agents.

Carcinomas of the Paranasal Sinuses and Nasal Cavity Treated With Radiotherapy at a Single Institution Over Five Decades: Are We Making Improvement?

PURPOSE

To compare clinical outcomes of patients with carcinomas of the paranasal sinuses and nasal cavity according to decade of radiation treatment.

METHODS AND MATERIALS

Between 1960 and 2005, 127 patients with sinonasal carcinoma underwent radiotherapy with planning and delivery techniques available at the time of treatment. Fifty-nine patients were treated by conventional radiotherapy; 45 patients by three-dimensional conformal radiotherapy; and 23 patients by intensity-modulated radiotherapy. Eighty-two patients (65%) were treated with radiotherapy after gross total tumor resection. Nineteen patients (15%) received chemotherapy. The most common histology was squamous cell carcinoma (83 patients).

RESULTS

The 5-year estimates of overall survival, local control, and disease-free survival for the entire patient population were 52%, 62%, and 54%, respectively. There were no significant differences in any of these endpoints with respect to decade of treatment or radiotherapy technique (p > 0.05, for all). The 5-year overall survival rate for patients treated in the 1960s, 1970s, 1980s, 1990s, and 2000s was 46%, 56%, 51%, 53%, and 49%, respectively (p = 0.23). The observed incidence of severe (Grade 3 or 4) late toxicity was 53%, 45%, 39%, 28%, and 16% among patients treated in the 1960s, 1970s, 1980s, 1990s, and 2000s, respectively (p = 0.01).

CONCLUSION

Although we did not detect improvements in disease control or overall survival for patients treated over time, the incidence of complications has significantly declined, thereby resulting in an improved therapeutic ratio for patients with carcinomas of the paranasal sinuses and nasal cavity.

Current status of the infrastructure and characteristics of radiation oncology in Korea

BACKGROUND

An analysis of radiotherapy infrastructure in Korea was performed in 2006 to collect data on treatment devices, the work force and new patients for future development plans.

METHODS

The survey included radiotherapy centers, their major equipment and personnel. The centers were categorized into four levels: level 0 (stand-alone teletherapy units); level 1 (teletherapy, brachytherapy, treatment planning system, and at least the part-time service of a medical physicist); level 2 (level 1 plus individual customized radiotherapy block and full-time medical physicist); and level 3 [level 2 plus intensity-modulated radiation therapy (IMRT), intra-operative radiation therapy or stereotactic radiotherapy].

RESULTS

A total of 61 facilities delivered radiation therapy with 104 megavoltage devices, which included 96 linear accelerators, two cobalt 60 units, three Tomotherapy, two CyberKnife units and one proton accelerator. There were 28,789 new radiotherapy patients in 2004. Personnel included 132 radiation oncologists, 50 radiation oncology residents, 64 physicists, 130 nurses and 369 radiation therapy technologists. Thirty-two percent (20 facilities) used a CT-simulator, 66% (40) used a PET or PET-CT scanner, and 35% (22) had the capacity to implement IMRT. Centers were also divided into four levels: 41% were included in level 3, 31% in level 2, 25% in level 1 and 3% in level 0.

CONCLUSIONS

There is a shortage of human resources. The distribution of megavoltage units per million inhabitants over the country was inadequate; geographic disparities were noted. Furthermore, the necessity of quality assurance for recent high-technology radiation therapy is increasing.

Impact of adoption of chemoradiotherapy on the outcome of cervical cancer in Ontario: results of a population-based cohort study

PURPOSE

To describe the adoption of concurrent cisplatin-based chemoradiotherapy (C-CRT), and to evaluate its impact on the outcome of cervical cancer in Ontario.

METHODS

We used a population-based cancer registry to identify the 4,069 patients with invasive carcinoma of the cervix diagnosed in Ontario between 1992 and 2001. We linked electronic records of treatment to the registry. We described time trends in the use of C-CRT, and we compared survival before and after widespread adoption of C-CRT.

RESULTS

Over the study period, the proportion of patients treated with primary radical radiotherapy (RT) remained constant at approximately 42%. Between 1992 and 1998, less than 10% of RT cases received chemotherapy. Early in 1999, there was rapid adoption of C-CRT. Between 1999 and 2001, more than 60% of RT cases received C-CRT. There was a contemporaneous increase in overall 3-year survival from 71.1% in the 1995 to 1998 cohort to 75.9% in the 1999 to 2001 cohort (P = .03). There was no change in survival in patients treated with surgery alone. However, there was a significant increase in 3-year survival from 58.6% in the 1995 to 1998 cohort to 69.8% in the 1999 to 2001 cohort (P < .01) in the subpopulation of patients treated with primary RT +/- chemotherapy.

CONCLUSION

The adoption of C-CRT was associated with a significant improvement in overall survival of cervical cancer at the population level. The magnitude of the benefit of C-CRT in the general population was consistent with the results of the relevant clinical trials.

What will be the radiotherapy machine capacity required for optimal delivery of radiotherapy in Scotland in 2015?

AIMS

Lack of radiotherapy capacity has been cited as a reason for poor cancer outcomes reported in the United Kingdom. This modelling study was conducted to ensure sufficient capacity in the future and to aid health service planning.

METHODS

The predicted changes in the incidence of each cancer type to 2015 were calculated using the age-period-cohort technique. To develop the model the indications for radiotherapy now and in 2015 were established, as were the fractionation schedules for each clinical scenario. The optimal radiotherapy utilisation rates and required radiotherapy capacity were estimated for 2005 and for 2015.

RESULTS

Cancer incidence is expected to rise by 18.9% by 2015. In Scotland, the estimated optimal radiotherapy utilisation rate during initial management is 44.2-47.9%. The model suggested that currently for optimal delivery, the capacity for 195,300-256,300 fractions is required. Due to predicted changes in the patient population, it is anticipated that requirements will increase to between 276,400 and 354,200 fractions per annum by 2015. Based on the current working practices, this is a 20-54% increase in current capacity, or from 5 to 6-7.6 machines per million head of population.

CONCLUSIONS

In order to meet the current and projected demand, a marked increase in the provision of radiotherapy machine capacity will be required in Scotland by 2015.

Radiobiological mechanisms in inflammatory diseases of low-dose radiation therapy

PURPOSE

Whereas X-irradiation with high doses is established to exert pro-inflammatory effects, low-dose radiotherapy (LD-RT) with single fractions below 1.0 Gy and a total dose below 12 Gy is clinically well known to exert anti-inflammatory and analgesic effects on several inflammatory diseases and painful degenerative disorders. Experimental studies to confirm the effectiveness, the empirical dose and fractionation schemes, and the underlying radiobiological mechanisms are still fragmentary.

METHOD

The anti-inflammatory efficiency of LD-RT was confirmed in several experimental in vitro and in vivo models.

RESULTS

In vitro studies revealed a variety of mechanisms related to the anti-inflammatory effect, in particular the modulation of cytokine and adhesion molecule expression on activated endothelial cells and leukocytes, and of nitric oxide (NO) production and oxidative burst in activated macrophages and native granulocytes.

CONCLUSION

Inflammatory diseases are the result of complex and pathologically unbalanced multicellular interactions. It is, therefore, reasonable to assume that further molecular pathways and cellular components contribute to the anti-inflammatory effect of LD-RT. This review discusses data and models revealing aspects of the mechanisms underlying the anti-inflammation induced by low doses of X-irradiation and may serve as a basis for systematic analyses, necessary to optimize LD-RT in clinical practice.

[Radiotherapy of Graves' ophthalmopathy--state of the art and review of the literature]

Graves' ophthalmopathy (GO), the most frequent extrathyroidal manifestation of Graves' disease, is a disorder of autoimmune origin, the pathogenic mechanisms of which are still incompletely understood. Although GO is severe in only 3-5% of affected individuals, quality of life is severely impaired even in patients with mild GO. The role of radiotherapy in the management of GO is discussed controversially. However, recent randomized clinical trials have, with one exception, confirmed that orbital radiotherapy is an effective and safe therapeutic procedure for GO. This article describes the sequences, dosages and fractionation schemes as well as the risks and side effects of the radiotherapy.

Austrian Breast Cancer Patterns-of-Care Studies PCS93 and PCS01 versus PCS85 to Identify Changes in National Practice

PURPOSE

To determine the patterns of evaluation and treatment in Austrian breast cancer patients treated with surgery and radiotherapy in 1993 (PCS93) and 2001 (PCS01), and to compare these with the results of PCS85.

MATERIAL AND METHODS

According to the evaluation process of the Austrian PCS85, ten randomly selected patient charts from every Austrian radiotherapy center from 1993 (n=100) as well as 2001 (n=120) were reviewed. The work-up included surgical and (histo)pathologic information, systemic therapy and detailed information on radiation therapy.

RESULTS

Availability of histopathologic core data improved distinctly between 1985 and 2001. In 1985, treatment planning included fluoroscopic simulation and/or computed tomography in 55% of the cases as compared to 100% in 2001. The technical equipment in Austria changed distinctly. In 2001, 84% of the breast/chest wall fields and all regional node fields (+/- electrons) were treated by photons. Radiotherapy of the supraclavicular (77% vs. 28%), internal mammary (62% vs. 7.5%) and axillary nodes (51% vs. 5%) diminished from 1985 to 2001. A tumor bed boost was given in 34% of the patients in 1985 compared to 73% in 2001. The use of wedges (21% vs. 97%) and the number of port films (26% vs. 90%) increased substantially.

CONCLUSION

Comparing both recent Austrian Patterns-of-Care surveys to the results obtained in 1985, an obvious increase in the quality level of histopathologic reporting as well as radiation treatment planning and delivery was found.

Targeted Therapy for Brain Metastases: Improving the Therapeutic Ratio

Brain metastasis is the most common intracranial malignancy in adults. Improvements in modern imaging techniques are detecting previously occult brain metastases, and more effective therapies are extending the survival of patients with invasive cancer who have historically died from extracranial disease before developing brain metastasis. This combination of factors along with increased life expectancy has led to the increased diagnosis of brain metastases. Conventional treatment has been whole brain radiotherapy, which can improve symptoms, but potentially results in neurocognitive deficits. Several strategies to improve the therapeutic ratio are currently under investigation to either enhance the radiation effect, thereby preventing tumor recurrence or progression as well as reducing collateral treatment-related brain injury. In this review article, we discuss new directions in the management of brain metastases, including the role of chemical modifiers, novel systemic agents, and the management and prevention of neurocognitive deficits.

State-of-the-art radiotherapy in the management of clinically localized prostate carcinoma

Four Phase III trials demonstrating higher prostate-specific antigen control rates in prostate cancer patients treated with higher doses of radiation have changed the standard of care. Emerging on-line technologies, improved imaging and computer algorithms, combined with an improved understanding of how best to apply them, have allowed radiation oncologists to move ever closer to the optimal application of curative radiation. This technology allows a higher dose to be delivered to tumor-bearing areas while minimizing the dose delivered to surrounding normal tissues. Real-time adaptive techniques have made each step more accurate, and commercialization has increasingly moved these advances further into the community setting. Phase III trials have also helped to define the role of hormonal therapy in combination with radiation and the benefits of prophylactic pelvic nodal radiotherapy in subsets of patients. We have also learnt how to optimize the use of prostate-specific antigen to better determine success and failure following radiotherapy.

Highlights of the European Association of Nuclear Medicine Congress, Athens, Greece, 30 September to 4 October 2006

The 2006 EANM Congress, held in Athens, Greece, was once again a major event in the nuclear medicine scientific and educational calendar. The scientific programme, which included the second biennial ISRTRD meeting, confirmed the major developments taking place in (1) the diagnostic and prognostic uses of nuclear medicine imaging (both in PET and in single-photon studies), (2) radionuclide therapies, (3) radiochemistry and radiopharmacy, and (4) physics. This paper outlines the major findings in each of these areas.

Adhesion molecules in radiotherapy

Recent studies have documented changes in adhesion molecule expression and function after exposure to ionizing radiation. Adhesion molecules mediate cell-cell and cell-matrix interactions and are essential for a variety of physiological and pathological processes including maintenance of normal tissue integrity as well as tumor development and progression. Consequently, modulation of adhesion molecules by radiation may have a role in radiation-induced tumor control and normal tissue damage by interfering with cell signaling, radioresistance, metastasis, angiogenesis, carcinogenesis, immune response, inflammation and fibrosis. In addition, the interactions of radiation with adhesion molecules could have a major impact in developing new strategies to increase the efficacy of radiation therapy. Remarkable progress has been made in recent years to design targeted drug delivery to radiation-up-regulated adhesion molecules. Furthermore, the inhibition of adhesion, migration, invasion and angiogenesis by blocking adhesion receptors may represent a new therapeutic approach to improve tumor control and decrease radiation toxicity. This review is focused on current data concerning the mechanistic interactions of radiation with adhesion molecules and the possible clinical-pathological implications in radiotherapy.

[Valorisation of high technology radiotherapy in Europe]

In order to support adoption and dissemination into clinical practice of innovative treatment strategies, being almost by definition more expensive than the corresponding standard treatments, an appropriate reimbursement is a prerequisite. This article describes different possible financing systems in the context of technological advances in radiation oncology and analyses if and how the reimbursement issue has been tackled in European radiotherapy centres.

Current role of radiation therapy in the management of malignant brain tumors

The objective of this article is to explain how the current management of malignant brain tumors has evolved, using the foundation of evidence-based literature. Radiotherapy plays a central role in the multidisciplinary management of primary brain tumors and brain metastases. The techniques of radiotherapy continue to be refined to optimize local control while minimizing potential treatment-related neurocognitive toxicities.

The role of radiation therapy in benign diseases

Although adequate prospective data are lacking, radiation therapy seems to be effective for many benign diseases and remains one of the treatment modalities in the armamentarium of medical professionals. Just as medication has potential adverse effects, and surgery has attendant morbidity, irradiation sometimes can be associated with acute and chronic sequelae. In selecting the mode of treatment, most radiation oncologists consider the particular problem to be addressed and the goal of therapy in the individual patient. It is the careful and judicial use of any therapy that identifies the professional. With an understanding of the current clinical data, treatment techniques, cost, and potential detriment, the goal is to provide long-term control of the disease while minimizing unnecessary treatment and potential risks of side effects. The art lies in balancing benefits against risks.

Primary CNS lymphoma in immunocompetent patients from 1989 to 2001: a retrospective analysis of 164 cases uniformly diagnosed by stereotactic biopsy

BACKGROUND

We present outcome data of a cohort of 164 immunocompetent PCNSL patients uniformly diagnosed at a single center for stereotactic neurosurgery, and evaluate the acceptance and impact of combination radiotherapy (RT) and chemotherapy (CHT) with high-dose methotrexate (HD-MTX) over time.

METHOD

We assessed choice of treatment and patient survival in a series of 164 PCNSL cases diagnosed from 1989 to 2001, and performed a re-evaluation of histopathology and pre-operative clinical data.

FINDINGS

From 1989 to 1993, RT was the predominant therapy, and additional CHT did not improve survival. After 1994, the use of combination CHT/RT increased continuously, consistently contained MTX, and was associated with longer survival than RT only: median survival was 14 months after CHT/RT (2-year survival 35.7%) and 10 months (2-year survival 26.2%) after RT only (not significant). Overall median survival remained poor, increasing from six (1989-1993) to nine months (1994-2001) (p = 0.008). Survival was variable, with a few patients surviving >4 years after diagnosis in the CHT/RT as well as in the RT only group.

CONCLUSIONS

Despite considerable improvement of PCNSL therapy, the overall benefit of combined CHT/RT versus RT only was lower than that expected from previous phase II clinical trials. The striking variability of survival in either treatment group may suggest a yet undefined biological heterogeneity of PCNSL, which may also include a more aggressive PCNSL subtype in the group of patients with rapidly progressive disease and not eligible for standard therapy.

History of the treatment of childhood ALL: a paradigm for cancer cure

The history of the treatment of childhood leukemia from 1950 to the present is reviewed here. Particular emphasis is placed on the 'Total Therapy' studies conducted at St Jude Children's Research Hospital in Memphis, Tennessee. Under the guidance of Donald Pinkel, MD, the first medical director of St Jude, variations in chemotherapy and craniospinal irradiation were tried, and by Study XV, begun in 2000, a 4-year event-free survival of 92+/-7% had been achieved. Strengths and weaknesses in the current treatment of childhood leukemia are discussed as well as possibilities for the future.