The role of local treatment in the cure of cancer

The use of radiotherapy, surgery and chemotherapy in the curative treatment of cancer: results from the FORTY (Favourable Outcomes from RadioTherapY) project

OBJECTIVES

Radiotherapy, surgery and chemotherapy play key roles in the curative treatment of cancer, alone and in combination. Quantifying their roles is essential for equipment provision and workforce planning. The estimate that 40% of cancer patients are cured by RT has been used extensively to inform and influence policy but is relatively old and warrants review.

METHODS

Patient, tumour and treatment event data was obtained for the 5 year period from 2009 to 2013, allowing a further 5 years for survival outcomes to be known. We analysed patient-level data on utilisation of surgery, radiotherapy, and chemotherapy in cancer patients in England. Data were sourced from Public Health England, using National Cancer Registrations, the National Radiotherapy Dataset (RTDS) and the Systemic Anti-Cancer Therapy Dataset (SACT). All tumour sites (excluding C44) and ages were included. We analysed three cohorts: all patients [n = 1,029,569], patients who survived 5 years or more [n = 537,970] and patients who survived <5 years [n = 491,599].

RESULTS

Overall cancer-specific 5-year survival was 52%, and in those patients, surgery was the most common curative treatment, with 80% receiving surgery, alone or in combination; radiotherapy was delivered to 39% and chemotherapy to 29%; 45% received two and 13% all three modalities.

CONCLUSIONS

The high proportion receiving multi-modality treatment emphasises the importance of integrated, resourced, multidisciplinary cancer care. Radiotherapy was delivered to almost 40% of patients who survived 5 years which underlines its importance in cancer management.

ADVANCES IN KNOWLEDGE

The results are essential in planning cancer services. They also inform the public health narrative.

MR-guided radiotherapy for prostate cancer: state of the art and future perspectives

Advances in radiotherapy technology have increased precision of treatment delivery and in some tumour types, improved cure rates and decreased side effects. A new generation of radiotherapy machines, hybrids of an MRI scanner and a linear accelerator, has the potential to further transform the practice of radiation therapy in some cancers. Facilitating superior image quality and the ability to change the dose distribution online on a daily basis (termed "daily adaptive replanning"), MRI-guided radiotherapy machines allow for new possibilities including increasing dose, for hard to treat cancers, and more selective sparing of healthy tissues, where toxicity reduction is the key priority.These machines have already been used to treat most types of cancer, although experience is still in its infancy. This review summarises the potential and current evidence for MRI-guided radiotherapy, with a predominant focus on prostate cancer. Current advantages and disadvantages are discussed including a realistic appraisal of the likely potential to improve patient outcomes. In addition, horizon scanning for near-term possibilities for research and development will hopefully delineate the potential role for this technology over the next decade.

Atomically precise silver clusterzymes protect mice from radiation damages

BACKGROUND

As we know, radiotherapy plays an irreplaceable role in the clinical management on solid tumors. However, due to the non-specific killing effects of ionizing radiation, normal tissues damages would be almost simultaneous inevitably. Therefore, ideal radioprotective agents with high efficiency and low toxicity are always desirable. In this work, atomically precise Ag14 clusterzymes were developed, and their applications in radioprotection were studied in vitro and in vivo for the first time.

METHODS

The ultra-small glutathione supported Ag14 clusterzymes were synthesized by convenient sodium borohydride (NaBH4) reduction of thiolate-Ag (I) complexes and then they were purified by desalting columns. The enzyme-like activity and antioxidant capacity of Ag14 clusterzymes have been tested by various commercial kits, salicylic acid method and electron spin resonance (ESR). Next, they were incubated with L929 cells to evaluate whether they could increase cell viability after γ-ray irradiation. And then Ag14 clusterzymes were intravenously injected into C57 mice before 7 Gy whole-body γ-ray irradiation to evaluate the radioprotection effects in vivo. At last, the in vivo toxicities of Ag14 clusterzymes were evaluated through biodistribution test, hematological details, serum biochemical indexes and histological test in female Balb/c mice with intravenous injection of Ag14 clusterzymes.

RESULTS

Our studies suggested atomically precise Ag14 clusterzymes were potential radioprotectants. Ag14 clusterzymes exhibited unique superoxide dismutase (SOD)-like activity, strong anti-oxidative abilities, especially on •OH scavenging. The Ag14 clusterzymes could effectively improve cell viability through eliminating ROS and prevent DNA damages in cells dealt with γ-ray irradiation. In vivo experiments showed that Ag14 clusterzymes could improve the irradiated mice survival rate by protecting hematological systems and repairing tissue oxidative stress damage generated by γ-ray irradiation. In addition, bio-distribution and toxicological experiments demonstrated that the ultrasmall Ag14 clusterzymes could be excreted quickly from the body by renal clearance and negligible toxicological responses were observed in mice up to 30 days.

CONCLUSION

In summary, atomically precise, ultrasmall and water soluble Ag14 clusterzymes with SOD-like activity were successfully developed and proved to be effective both in vitro and in vivo for radioprotection. Furthermore, with atomically precise molecular structure, Ag14 clusterzymes, on aspect of the catalytic and optical properties, may be improved by structure optimization on atom-scale level for other applications in disease diagnosis and treatment.

The Intestinal Microbiota: Our Best Frenemy in Radiation-Induced Damages?

High-dose ionizing radiation used during cancer radiotherapy is associated with the induction of hematopoietic, gastrointestinal, and cerebrovascular injuries. In a recent Science issue, Guo et al. demonstrated that the gut microbiota-and its associated metabolites-play a central role in protecting against high-dose radiation.

An introduction to proton beam therapy

Radiotherapy is a highly effective anti-cancer treatment commonly used alongside systemic therapies and surgery to achieve long-term cancer-free survival. Conventional radiotherapy uses photon beams to deliver a high dose of radiation to the tumour volume to eradicate cancer cells. This has to be offset against the irradiation of surrounding normal tissues, as increasing this dose causes more treatment-related toxicity. In August 2018, the NHS's first high energy proton beam therapy centre opened at The Christie NHS Foundation Trust in Manchester. A second NHS centre is scheduled to open in 2020 at the University College London Hospitals NHS Trust. Proton beam therapy may offer dosimetric advantages compared to conventional radiotherapy as a result of its characteristic dose deposition - proton beams deliver a comparatively higher proportion of their dose to the target volume relative to normal tissues, without significant exit doses when compared to conventional photon therapy. Therefore proton beam therapy may be indicated for certain tumours situated next to critical organs or in the paediatric population where quality of life and the reduction of secondary effects from radiation are particularly significant. The indications for proton beam therapy and patient outcomes after treatment will be carefully monitored and evaluated in order to provide a robust evidence base for its use.

Knockdown of long non-coding RNA TINCR decreases radioresistance in colorectal cancer cells

An increasing number of studies have revealed the role of long non-coding RNAs in cancer. However, the mechanisms of action and functional utility in colorectal cancer (CRC) have not been fully elucidated. Here we describe the functional role and potential mechanism of TINCR (terminal differentiation-induced non-coding RNA) in CRC. Firstly, TINCR was selected using sequencing analyses and the starBase database. Cell Counting Kit-8, scratch wound healing, and transwell assays revealed that TINCR inhibited proliferation and migration in SW620 and HTC116 cells. Intriguingly, TINCR expression was up-regulated in a radioresistant CRC cell line (SW620R). Although TINCR had no significant effects on SW620R cell proliferation or migration, knockdown of TINCR reduced the radioresistance, and its overexpression had opposite effects. We then focused on transcription factor 4 (TCF4) as it is downregulated in CRC and associated with increased stemness in tumors. We found that TINCR and TCF4 levels were positively related in SW620R cells. TINCR knockdown reduced sphere formation ability in SW620R cells. TINCR also suppressed the OCT4 and SOX2 stemness genes, despite having no effect on NANOG. The expression levels of these genes were substantially higher in SW620R than in SW620 cells. To further explore the mechanism of TINCR and radioresistance, miR-137 was analyzed as it targets TCF4. We firstly confirmed that TCF4 is a target of miR-137. We then identified that TINCR knockdown enhanced miR-137 expression in SW620R cells. Collectively, these findings suggest that TINCR knockdown inhibits TCF4 by regulating miR-137 expression.

Continuing Medical Education in Radiation Oncology

Continuing medical education (CME) has always been considered very important in modern medical practice. Physicians should not be left completly free to continuously educate themselves, but they should receive at least a minimal level of education accreditated by scientific and/or Government Institutions. The main goal of CME is to improve the quality of medical practice. In order to adequately define programs and contents of CME in radiation oncology, we must first identify the professional profile of the radiation oncologist: he is a physician engaged in the clinical practice of oncology, and in particular in the loco-regional cure of cancer by sophisticated technologies; he has the responsibility of diagnosis, treatment, follow-up and supportive care of cancer patients, collaborating within a multidisciplinary approach with the radiologist, the medical oncologist, the surgeon and the medical physicist. The european core curriculum in radiotherapy and the procedures employed in the daily practice could be models to develop postgraduate teaching and CME for the radiation oncologists in Italy. In fact, many countries, such as the USA, France, Belgium and the United Kingdom, have already developed accreditated programs of CME. Unfortunately, Italy still lacks this type of program. What is mostly needed to implement CME activities is a close cooperation between representatives of radiation oncology associations and Government Institutions to define laws, programs, an Accreditation Council, a minimum of formative credits, accreditated categories of education regulating CME, as well as the resources devoted to it.

Oxidative Stress: Harms and Benefits for Human Health

Oxidative stress is a phenomenon caused by an imbalance between production and accumulation of oxygen reactive species (ROS) in cells and tissues and the ability of a biological system to detoxify these reactive products. ROS can play, and in fact they do it, several physiological roles (i.e., cell signaling), and they are normally generated as by-products of oxygen metabolism; despite this, environmental stressors (i.e., UV, ionizing radiations, pollutants, and heavy metals) and xenobiotics (i.e., antiblastic drugs) contribute to greatly increase ROS production, therefore causing the imbalance that leads to cell and tissue damage (oxidative stress). Several antioxidants have been exploited in recent years for their actual or supposed beneficial effect against oxidative stress, such as vitamin E, flavonoids, and polyphenols. While we tend to describe oxidative stress just as harmful for human body, it is true as well that it is exploited as a therapeutic approach to treat clinical conditions such as cancer, with a certain degree of clinical success. In this review, we will describe the most recent findings in the oxidative stress field, highlighting both its bad and good sides for human health.

Direct and bystander radiation effects: a biophysical model and clinical perspectives

In planning treatment for each new patient, radiation oncologists pay attention to the aspects that they control. Thus their attention is usually focused on volume and dose. The dilemma for the physician is how to protract the treatment in a way that maximizes control of the tumor and minimizes normal tissue injury. The initial radiation-induced damage to DNA may be a biological indicator of the quantity of energy transferred to the DNA. However, until now the biophysical models proposed cannot explain either the early or the late adverse effects of radiation, and a more general theory appears to be required. The bystander component of tumor cell death after radiotherapy measured in many experimental works highlights the importance of confirming these observations in a clinical situation.

[Follow-up in patients with early breast cancer]

Breast cancer incidence remains the highest among gynaecologic neoplasms. Once they have achieved their treatments, patients should undergo careful follow-up. It aims at detecting early local recurrence or controlateral breast cancer. Based on large cohorts, clinical and radiological follow-up procedures come from guidelines realised by scientific organisations. We evaluated our regional practices in Franche-Comté and compared them to current guidelines. Patients with early breast cancer positive for hormonal receptors filled a questionnaire concerning their follow-up. It included patients treated from 1999 to 2005. When frequency of consultation is evaluated, only half of the patients undergo what is recommended. Whereas mammography and non-validated complementary exams are more regularly realised. Patients consulting more one practician have a better compliance. Our study underlines significant disparities among patients follow-up. Better interactions between physicians and a greater implication of patients in their follow-up would increase its quality.

Germline glutathione S-transferase variants in breast cancer: relation to diagnosis and cutaneous long-term adverse effects after two fractionation patterns of radiotherapy

PURPOSE

To explore whether certain glutathione S-transferase (GST) polymorphisms are associated with an increased risk of breast cancer or the level of radiation-induced adverse effects after two fractionation patterns of adjuvant radiotherapy.

METHODS AND MATERIALS

The prevalence of germline polymorphic variants in GSTM1, GSTP1, and GSTT1 was determined in 272 breast cancer patients and compared with that in a control group of 270 women from the general population with no known history of breast cancer. The genetic variants were determined using multiplex polymerase chain reaction followed by restriction enzyme fragment analysis. In 253 of the patients surveyed for radiotherapy-induced side effects after a median observation time of 13.7 years (range, 7-22.8 years), the genotypes were related to the long-term effects observed after two fractionation patterns (treatment A, 4.3 Gy in 10 fractions for 156 patients; and treatment B, 2.5 Gy in 20 fractions for 97; both administered within a 5-week period).

RESULTS

None of the GST polymorphisms conferred an increased risk of breast cancer, either alone or in combination. Compared with treatment B, treatment A was followed by an increased level of moderate to severe radiation-induced side effects for all the endpoints studied (i.e., degree of telangiectasia, subcutaneous fibrosis and atrophy, lung fibrosis, costal fractures, and pleural thickening; p <0.001 for all endpoints). A significant association was found between the level of pleural thickening and the GSTP1 Ile105Val variant.

CONCLUSION

The results of this study have illustrated the impact of hypofractionation on the level of adverse effects and indicated that the specific alleles of GSTP1, M1, and T1 studied here may be significant in determining the level of adverse effects after radiotherapy.

Epidemiological aspects of hadron therapy: A prospective nationwide study of the Austrian project MedAustron and the Austrian Society of Radiooncology (OEGRO)

BACKGROUND

The planned MedAustron hadron therapy facility is designed to compare proton and carbon ion beam therapy under the same technical conditions. For the calculation of the number of potential patients for hadron therapy so far, only epidemiological estimations on cancer incidence are available without inclusion of the percentage of patients routinely referred to conventional radiotherapy.

MATERIALS AND METHODS

Nationwide prospective survey to collect disease and treatment related data on patients receiving conventional radiotherapy at all 12 treatment facilities. Epidemiological cancer incidence (Statistic Austria 1999) were correlated with the number of patients receiving conventional radiotherapy. Based on published clinical and experimental results on proton and carbon ion therapy, a calculation of patient's subgroups suitable for hadron therapy was performed at five European University hospitals involved in the HICAT, CNAO, ETOILE and MEDAustron project. Using the mean values of the University specific percentages per tumour site, the number of potential patients was estimated.

RESULTS

In Austria, a total of 3783 patients started radiotherapy during the study period of 3 months resulting in an approximated number of 15132 patients per year. The number of potential patients was estimated to 2044 per year, representing 5.6% of all newly diagnosed cancer patients and 13.5% of all irradiated cancer patients.

CONCLUSION

There is a clear place for a hadron therapy facility in Austria, based on pattern of care in radiotherapy, cancer incidence and indications.

Segmental and dynamic intensity-modulated radiotherapy delivery techniques for micro-multileaf collimator

A leaf sequencing algorithm has been implemented to deliver segmental and dynamic multileaf collimated intensity-modulated radiotherapy (SMLC-IMRT and DMLC-IMRT, respectively) using a linear accelerator equipped with a micro-multileaf collimator (mMLC). The implementation extends a previously published algorithm for the SMLC-IMRT to include the dynamic MLC-IMRT method and several dosimetric considerations. The algorithm has been extended to account for the transmitted radiation and minimize the leakage between opposing and neighboring leaves. The underdosage problem associated with the tongue-and-groove design of the MLC is significantly reduced by synchronizing the MLC leaf movements. The workings of the leaf sequencing parameters have been investigated and the results of the planar dosimetric investigations show that the sequencing parameters affect the measured dose distributions as intended. Investigations of clinical cases suggest that SMLC and DMLC delivery methods produce comparable results with leaf sequences obtained by root-mean-square (RMS) errors specification of 1.5% and lower, approximately corresponding to 20 or more segments. For SMLC-IMRT, there is little to be gained by using an RMS error specification smaller than 2%, approximately corresponding to 15 segments; however, more segments directly translate to longer treatment time and more strain on the MLC. The implemented leaf synchronization method does not increase the required monitor units while it reduces the measured TG underdoses from a maximum of 12% to a maximum of 3% observed with single field measurements of representative clinical cases studied.

Patient specific quality assurance for the delivery of intensity modulated radiotherapy

A patient specific quality assurance program has been developed to facilitate the clinical implementation of intensity modulated radiotherapy (IMRT) delivered using a micro-multileaf collimator. The methodology includes several dosimetric tasks that are performed prior to the treatment of each patient. Film dosimetry is performed for each individual field and for the multifield composite plan. Individual field measurements are performed at a depth of 5 cm in a water equivalent slab phantom; export of dose calculations from the treatment planning system is similarly specified. For the composite distribution, parameters from the patient plan are applied to an IMRT phantom, and film is exposed in an axial orientation. Distributions are compared with the aid of software developed for the specific tasks. The measured and calculated dose distributions can be superimposed and positioned graphically using move, rotate, and mirror tools, as well as by specifying isocenter coordinates and using fiducial marks. Horizontal and vertical profiles are available for analysis. Dose difference, distance-to-agreement, and gamma index, the minimum scaled multidimensional distance between a measurement and a calculation point determined in combined dose and physical distance space, are calculated along a specified isodose line and displayed. gamma provides an excellent measure of disagreement between measurement and calculation for complex intensity distributions. We specify 3% dose difference and 3 mm distance as our scaling acceptability criteria. Absolute dosimetry for each composite plan is performed using an ionization chamber. To date, excellent agreement between measurements and calculations has been observed.

Effect of topical morphine for mucositis-associated pain following concomitant chemoradiotherapy for head and neck carcinoma

BACKGROUND

Oral mucositis is the dose-limiting toxicity for patients receiving concurrent chemoradiotherapy regimens for tumors of the head and neck area. Currently, the management of established mucositis includes the use of topical anesthetics and systemic analgesics. Based on the clinical evidence of pain alleviation by topical morphine in patients with some inflammatory and painful conditions, a clinical study was undertaken to determine this effect on mucositis-associated pain.

METHODS

Twenty-six patients with head and neck malignancies treated with concomitant chemoradiotherapy for head and neck carcinoma who had severe painful mucositis (World Health Organization Grade 2 or higher) were enrolled. Patients were randomly assigned to morphine mouthwash (MO; 14 patients) or magic mouthwash (MG), a mixture of equal parts of lidocaine, diphenhydramine, and magnesium aluminum hydroxide (12 patients).

RESULTS

The duration of severe pain was 3.5 days less in the MO group compared with the MG group (P = 0.032). The intensity of oral pain was also significantly lower in the MO group compared with the MG group (P = 0.038). No patient in the MO group required third-step opiates for alleviation of the mouth pain. There was a significant difference in duration of severe functional impairment (P = 0.017). Five patients in the MG group complained of local side effects and only one in the MO group (P = 0.007).

CONCLUSIONS

For patients with head and neck carcinomas receiving concomitant chemoradiotherapy, MO is a simple and effective treatment to decrease the severity and duration of pain and the duration of functional impairment.

Breast cancer acute radiotherapy morbidity evaluated by different scoring systems

Reporting of the outcome of radiotherapy is not satisfactory without a description of the treatment-related side effects. The purposes of this paper were: (1) to evaluate the frequency and the severity of collateral skin reactions in a group of breast cancer patients; (2) to report the acute reactions using some current scoring systems and to compare the application of them, and (3) to investigate the variation between intra- and interobservers using these different scales. We studied 108 breast cancer patients who, after surgical treatment, received adjuvant radiotherapy. Clinical skin evaluation was always performed by the same radiotherapist the last day of treatment, and the collateral radiation effects were photographed at that moment to facilitate later evaluations by another two expert doctors. Normal tissue damage was scored according to the Radiation Therapy Oncology Group/The European Organisation for Research, and Treatment of Cancer/ (RTOG/EORTC), the Danish, the European, and the Biomed2 side-effect scales. The most frequent acute complications found were erythema (91.7%), dry desquamation (29.6%) and moist desquamation (35.2%). The reactions were classified as severe in 13.9, 23, 18.5 and 13% of the patients with each of the different systems used, respectively. The concordance between the scoring of radiation-induced side effects on the skin assessed by direct observation of the patients or by examination of the photographic document was sufficient. This is a warrant of accuracy in the evaluation of acute normal tissue lesions. Our results allow us to state the advantage of the RTOG system over the others in terms of evaluating the acute effects produced by radiotherapy of women with breast cancer.

Conformal radiotherapy and intensity-modulated radiotherapy--clinical data

Conformal radiotherapy (CRT) is based on three hypotheses: (i) a higher rate of local control can improve the survival rate; (ii) dose escalation can increase tumor control; and (iii) CRT allows the delivery of higher doses by decreasing the incidence of late effects. These postulates are now supported by several data. Three-dimensional conformal radiotherapy (3D-CRT) has markedly progressed since its introduction two decades ago. However, there are situations for which 3D-CRT cannot produce a satisfactory treatment plan because of complex target volume shapes or the close proximity of sensitive normal tissues. This is why intensity-modulated radiation therapy (IMRT) was introduced. Its aim is to overcome the limitations of 3D-CRT by adding modulators of beam intensity to beam shaping. IMRT can achieve nearly any dose distribution; however, the role of the planner remains crucial. CRT has been investigated mainly for prostate cancers and head and neck cancers. By and large, the clinical data, although still limited, seem to confirm the advantages of this type of radiotherapy. Dose escalation in prostate cancers improves the local control rate without increasing late effects and for this cancer site IMRT appears to be a significant advance over conventional 3D-CRT. In head and neck cancers the clinical data are still scarce but encouraging. CRT should be investigated in breast cancers with the aim of reducing the incidence of late effects. The available data underline the great potential for major progress in 3D-CRT and IMRT. The techniques are still costly and time consuming, nevertheless they merit investigation since their cost should decrease. Efforts should be concentrated on the specification of robust optimization criteria, taking into account clinical and radiobiological data.

Imaging in radiotherapy

Radiotherapy, more then any other treatment modality, relies heavily and often exclusively on medical imaging to determine the extent of disease and the spatial relation between target region and neighbouring healthy tissues. Radically new approaches to radiation delivery are inspired on CT scanning and treat patients in a slice-by-slice fashion using intensity modulated megavoltage fan beams. For quality assurance of complex 3-D dose distributions, MR based 3-D verificative dosimetry on irradiated phantoms has been described. As treatment delivery becomes increasingly refined, the need for accurate target definition increases as well and sophisticated imaging tools like image fusion and 3-D reconstruction are routinely used for treatment planning. While in the past patients were positioned on the treatment machines based exclusively on surface topography and the well-known skin marks, such approach is no longer sufficient for high-accuracy radiotherapy and special imaging tools like on-line portal imaging are used to verify and correct target positioning. Much of these applications rely on digital image processing, transmission and storage, and the development of standards, like DICOM and PACS have greatly contributed to these applications. Digital imaging plays an increasing role in many areas in radiotherapy and has been fundamental in new developments that have demonstrated impact on patient care.

Induction chemo-radiotherapy for squamous cell carcinoma of the thoracic esophagus: long-term results of a phase II study

BACKGROUND

This study was done to evaluate the results of the combined use of chemo- and radiotherapy before surgery in a group of patients with squamous cell esophageal carcinoma after a median follow-up period of more than 5 years.

METHODS

Between June 1987 and January 1995, 111 patients with squamous cell carcinoma of the thoracic esophagus were submitted to a preoperative course of radiotherapy (3000 cGy) and chemotherapy (cisplatin and 5-FU) before surgery in the First Division of General Surgery at the University of Verona.

RESULTS

The neoadjuvant treatment was completed in 90.9% of the cases (101/111). After an average of 29 days, 87 patients underwent surgery (operability rate: 78.3%) and, of these, 80 underwent esophagectomy (resectability rate: 91.9%). Histopathologic studies showed no residual disease in the specimen (T0) in 17 cases (21.2%), only microscopic clusters of neoplastic cells within the esophageal wall (Minimal Residual Disease, MRD) in 14 cases (17.5%) and in 5 cases the tumor did not extend beyond the submucosal layer (T1). The median overall survival time of the 111 patients who were eligible for the study protocol was 14 months, and the 2- and 5-year survival rates were 32.0% and 17.5%, respectively. Kaplan-Meier determination of survival showed a statistically significant difference between the good responders (T0, T1, and MRD) to the neoadjuvant treatment and the remaining cases. The 2- and 5-year survival rates were 50.3% and 34.9%, respectively, in the good responder group compared with 26.7% and 10.7%, respectively, in the other cases, with a median survival time of 24 months vs. 13 months, respectively.

CONCLUSIONS

The neoadjuvant treatment showed promising results, especially in the group of patients that had a good response. The identification of these patients may be the key to selecting which patients should be submitted to preoperative radio- and chemotherapy.

Quality control in health care: an experiment in radiotherapy planning for breast cancer patients after mastectomy

PURPOSE

The importance of evaluating and improving quality in clinical practice is now generally acknowledged. In this study we estimated different sources of variation in radiotherapy planning for breast cancer patients after mastectomy and sought to test the applicability of a reproducibility and repeatability (R&R) study in a clinical context.

METHODS

Eleven radiation oncologists planned radiotherapy three times for three different kinds of breast cancer patients without knowing they were handling the same patient three times. Variation was divided into different components: physicians as operators, patients as parts, and repeated measurements as trials. Variation due to difference across trials (repeatability), that across the physicians (reproducibility), and that across the patients (variability) were estimated, as well as interactions between physicians and patients. Calculation was based on the sum of squares, and analysis was supported by various graphical presentations such as range charts and box plots.

RESULTS

Some parts of the planning process were characterized by higher and different kinds of variation than the others. Interphysician variation (i.e., reproducibility) was not high but there were some clearly outlying physicians. The highest variation was in repeatability (= intraphysician variation). The major part of the variation was, however, that from patient to patient: 33% of the total in Parameter 1 and 85% of the total in Parameter 2.

CONCLUSIONS

R&R studies are applicable and are needed to evaluate and improve quality in clinical practice. This kind of analysis provides opportunities to establish which kinds of patients require particularly careful attention, which points in the process are most critical for variation, which are the most difficult aspects for each physician and call for more careful description in documents, and which physicians need further training.

[Local control of the primary tumor. Necessary step in control of cancer]

There is clear evidence for a cancer cure. The hypothesis behind a treatment with curative intent is the ability to eradicate all the cancer cells of a tumour. Out of three cancer deaths, one is related to local failure. In some cancers like breast carcinoma, death is mainly in relation with the development of distant metastases. Even in such a tumour, an improvement in local control can translate as better survival. Radiation therapy, often in association with surgery, is playing a major role in tumour local control. Such a local control is mandatory if cure is at aim. One of the main goals of clinical research is to find a good compromise between local control of the disease and a non mutilating surgical approach.

[Scoring system of late effects of radiations on normal tissues: the SOMA-LENT scale]

Radiation tolerance of normal tissues remains the limiting factor for delivering tumoricidal dose. The late toxicity of normal tissues is the most critical element of an irradiation: somatic, functional and structural alterations occur during the actual treatment itself, but late effects manifest months to years after acute effects heal, and may progress with time. The optimal therapeutic ratio ultimately requires not only complete tumor clearance, but also minimal residual injury to surrounding vital normal tissues. The disparity between the intensity of acute and late effects and the inability to predict the eventual manifestations of late normal tissue injury has made radiation oncologists recognize the importance of careful patient follow-up. There is so far no uniform toxicity scoring system to compare several clinical studies in the absence of a "common toxicity language". This justifies the need to establish a precise evaluation system for the analysis of late effects of radiation on normal tissues. The SOMA/LENT scoring system results from an international collaboration. European Organization Treatment of Cancer (EORTC) and Radiation Therapy Oncology Group (RTOG) have created subcommittees with the aim of addressing the question of standardized toxic effects criteria. This effort appeared as a necessity to standardize and improve the data recording, to then describe and evaluate uniform toxicity at regular time intervals. The current proposed scale is not yet validated, and should be used cautiously.

[Intraoperative radiotherapy in 1997]

Intra Operative Radiation Therapy (IORT) has been routinely used for the past 20 years. It is a feasible treatment, with a reasonable cost and an acceptable acute and late toxicity. There is so far no strong randomized trial demonstrating that IORT can improve overall survival. Nevertheless, in many institutions it is recognized as an efficient treatment in selected patients. In case of locally recurrent disease an incomplete gross resection is often the only choice; IORT in such a situation has led to very encouraging results. For locally advanced deep seated primary tumors IORT seems to improve local control. In the near future IORT should be used on a larger and stronger basis. The manufacturing of new mobile linac should allow more surgeons to perform IORT and to conduct clinical trials to confirm the present indications in cancers with high local malignancy.

Head and neck cancer

This synthesis of the literature on radiotherapy for head and neck cancer is based on 424 scientific articles, including 3 meta-analyses, 38 randomized studies, 45 prospective studies, and 246 retrospective studies. These studies involve 79174 patients. The literature review shows that radiotherapy, either alone or in combination with surgery, plays an essential role in treating head and neck cancers. When tumors are localized, many tumor patients can be cured by radiotherapy alone and thereby maintain full organ function (1, 2). Current technical advancements in radiotherapy offer the potential for better local tumor control with lower morbidity (3). This, however, will require more sophisticated dose planning resources. To further improve treatment results for advanced tumors, other fractionation schedules, mainly hyperfractionation, should be introduced (5). This mainly increases the demands on staff resources for radiotherapy. The combination of radiotherapy and chemotherapy should be subjected to further controlled studies involving a sufficiently large number of patients (4, 5). Interstitial treatment (in the hands of experienced radiotherapists) yields good results for selected cancers. The method should be more generally accessible in Sweden. Intraoperative radiotherapy should be targeted for further study and development.

Quality assurance in radiotherapy. European Society for Therapeutic Radiology and Oncology Advisory Report to the Commission of the European Union for the 'Europe Against Cancer Programme'

This document is now in the process of being endorsed by all National Scientific Societies of Radiotherapy and Medical Physics of the European countries. It can therefore not be formally considered as the definitive version and is still susceptible to benefit from further alterations or improvements.

Development of clinical radiotherapy since 1896

From the discovery of x-rays in November 1895 and the first publication in December 1985 it did not take long for the first x-ray therapy of cancer in January 1896. The first 25 years in the history of radiotherapy was not a very flattering period for the discipline. During the following 25 years, however, important developments in clinical radiotherapy occurred and in some countries the speciality of radiotherapy was established in the 1930s. In the last 50 years gradual changes have taken place and now modern radiotherapy is an established curative method in the treatment of cancer. The scientific background of radiotherapy is solid, and the understanding of cancer biology and radiobiology has improved drastically. The radiotherapists of today are cancer specialists, oncologists. The technical development has been enormous. The future of radiation oncology looks very promising, with local cancer treatment being shown to be most effective.

Report of long-term follow-up in a randomized trial comparing radiation therapy and radiation therapy plus hyperthermia to metastatic lymph nodes in stage IV head and neck patients

PURPOSE

The treatment of inoperable metastatic lymph nodes in patients with head and neck cancer represents a therapeutic challenge. Clinical results using conventional radiation therapy are disappointing; on the other hand, the evaluation of recent innovative radiotherapeutic methods is still pending. The end points of this analysis were focused on long-term local control, on its potential influence on survival, and on late toxicity of a previously reported randomized Phase III study comparing conventionally fractionated radical irradiation alone or combined with local hyperthermia in fixed and inoperable metastatic neck lymph nodes.

METHODS AND MATERIALS

The medical records of 41 patients (44 nodes) with advanced locoregional Stage IV squamous cell cancer of the head and neck and randomized to treatment in the period 1985-1986 with irradiation alone (22/23 evaluable nodes) or combined with external hyperthermia (18/21 evaluable nodes), were re-evaluated.

RESULTS

The statistically significant difference observed in "early" response (p = 0.0164) in favor of the combined treatment results in improved 5-year actuarial nodal control (p = 0.015). Clinical improvement noted in tumor control positively affects survival, leading to a statistically significant difference in survival at 5 years (p = 0.02). With respect to side effects, no clearly enhanced acute or late toxicity has been found; as severe late effects, two patients with bone necroses possibly related to the combined treatment have been observed. Thermal analysis failed to show a significant correlation between heating parameters and the end points of the study.

CONCLUSION

This report with 5-year follow-up confirms the efficacy and the absence of severe toxicity of the combination of radical radiation and hyperthermia in the treatment of metastatic lymph nodes in Stage IV squamous cell carcinoma of the head and neck.

Electrochemotherapy--a novel method of cancer treatment

A critical review is presented on a novel method of treating cancer by a combination of an electric field with chemotherapeutic agents. The work described here summarizes the current state of the technique known as electrical impulse chemotherapy (EIC) or electrochemotherapy (ECT). The review discusses in vitro results with specific cell lines, in vivo work on animals and clinical results on patients with squamous cell carcinomas of the head and neck. In all cases, it has been found that uptake of various drugs by the tumor cells can be increased markedly by EIC/ECT. Partial responses and complete cures have been observed without any damaging side-effects, provided the field strength is kept sufficiently low. ECT followed by injection of a low dose of interleukin-2 (IL-2) or IL-2 secreting cells has shown better results than ECT alone. There appears to be a systemic effect and a strong indication that an immune response may be elicited by this method of treatment. Finally, we discuss the challenges involved in hardware requirements for EIC/ECT and its future prospects for both drug delivery and gene therapy.