The population benefit of radiotherapy for cervical cancer: Local control and survival estimates for optimally utilized radiotherapy and chemoradiation

Mapping of Radiation Oncology and Gynecologic Oncology Services Available to Treat the Growing Burden of Cervical Cancer in Africa

PURPOSE

To meet the demand for cervical cancer care in Africa, access to surgical and radiation therapy services needs to be understood. We thus mapped the availability of gynecologic and radiation therapy equipment and staffing for treating cervical cancer.

METHODS AND MATERIALS

We collected data on gynecologic and radiation oncology staffing, equipment, and infrastructure capacities across Africa. Data was obtained from February to July 2021 through collaboration with international partners using Research Electronic Data Capture. Cancer incidence was taken from the International Agency for Research on Cancer's GLOBOCAN 2020 database. Treatment capacity, including the numbers of radiation oncologists, radiation therapists, physicists, gynecologic oncologists, and hospitals performing gynecologic surgeries, was calculated per 1000 cervical cancer cases. Adequate capacity was defined as 2 radiation oncologists and 2 gynecologic oncologists per 1000 cervical cancer cases.

RESULTS

Forty-three of 54 African countries (79.6%) responded, and data were not reported for 11 countries (20.4%). Respondents from 31 countries (57.4%) reported access to specialist gynecologic oncology services, but staffing was adequate in only 11 countries (20.4%). Six countries (11%) reported that generalist obstetrician-gynecologists perform radical hysterectomies. Radiation oncologist access was available in 39 countries (72.2%), but staffing was adequate in only 16 countries (29.6%). Six countries (11%) had adequate staffing for both gynecologic and radiation oncology; 7 countries (13%) had no radiation or gynecologic oncologists. Access to external beam radiation therapy was available in 31 countries (57.4%), and access to brachytherapy was available in 25 countries (46.3%). The number of countries with training programs in gynecologic oncology, radiation oncology, medical physics, and radiation therapy were 14 (26%), 16 (30%), 11 (20%), and 17 (31%), respectively.

CONCLUSIONS

We identified areas needing comprehensive cervical cancer care infrastructure, human resources, and training programs. There are major gaps in access to radiation oncologists and trained gynecologic oncologists in Africa.

Characteristics and survival of patients with gynecological cancers who refuse radiotherapy: a retrospective cohort study

BACKGROUND

Radiotherapy improves survival for many cancer patients. However, some patients still refuse radiotherapy despite the recommendations of their physicians. We aimed to investigate the impact of refusing recommended radiotherapy on overall survival in patients with gynecological cancers (GC) and attempted to describe what characteristics are associated with the refusal of radiotherapy.

METHODS

Data were extracted from the Surveillance, Epidemiology and End Result (SEER) database for patients who were diagnosed with GC and recommended for radiotherapy between 1988 and 2016. Kaplan-Meier and multivariate Cox regression analyses were utilized to analyze the impact of refusal of radiotherapy on overall survival. Univariate and multivariate logistic regression analyses were used to identify characteristics associated with refusal of radiotherapy.

RESULTS

In total, 1,226 of 208,093 patients (0.6%) refused radiotherapy. Multivariate Cox regression analysis showed that refusal of radiotherapy was associated with poorer overall survival in GC patients with stage I/II [hazard ratio (HR) = 1.64; 95% confidence interval (CI), 1.50-1.79], but may not affect overall survival in patients with stage III/IV (HR = 1.03; 95%CI, 0.84-1.25). Multivariate logistic regression analysis demonstrated that factors such as older age (40-65 years, > 65 years), unmarried status (divorced, single, widowed), higher foreign-born rate (1.87-2.82%, 1.51-2.19), refusal of surgery (recommended but not performed), and higher grade (poorly differentiated, undifferentiated/anaplastic) may increase the likelihood of refusing radiotherapy (all P < 0.05). Factors that may reduce the likelihood of refusing radiotherapy include higher income (> 42,810$), lower grade (well-differentiated), primary site of ovarian cancer, and no/unknown chemotherapy (all P < 0.05).

CONCLUSION

Refusal of radiotherapy is related to worse overall survival in GC patients with stage I/II, and many characteristics may affect a patient's choice of refusal of radiotherapy.

Safety and efficacy of single insertion accelerated MR-image guided brachytherapy following chemo-radiation in locally advanced cervix cancer: modifying our EMBRACE during the COVID pandemic

BACKGROUND

Utero-vaginal brachytherapy (BT) is an irreplaceable care component for the curative treatment of locally advanced cervix cancer (LACC). Magnetic Resonance Imaging (MRI)-image guided adaptive BT (IGABT) using the GYN-GEC-ESTRO EMBRACE guidelines is the international care standard. Usually following chemo-radiation therapy (CRT), IGABT has high proven utility in LACC but requires significant health system resources. Timely access was disrupted by the COVID-19 pandemic which challenged us to re-design our established IGABT care pathway.

METHODS

From April 2020 consecutive patients with LACC were enrolled after CRT in a single arm exploratory non-inferiority study of a modified IGABT (mIGABT) protocol. This delivered an iso-effective IGABT dose (39.3 Gy: EQD2: α/β10Gy concept) over a 24-h period during a single overnight hospitalisation.

RESULTS

Fourteen LACC patients received mIGABT from April 2020 to March 2022. Median age was 62.5 years (37-82 years). LACC histology was primary squamous (9/14) or adeno-carcinoma (5/14). International Federation of Gynaecology and Obstetrics (FIGO) 2018 stages ranged from IB1/2 (N = 3), IIA1/IIB (5), IIIB (2), IIIC1/2 (4) with mean ± standard deviation (SD) gross tumour volume-at-diagnosis (GTV_D) of 37.7 cc ± 71.6 cc. All patients achieved complete metabolic, clinical, and cytologic cancer response with CRT and IGABT. High-risk HPV was cleared by 6-months. Complete MRI-defined cancer response before mIGABT (GTV_Fx1) was seen in 77% of cases (10/13). Only two women developed metastatic disease and one died at 12-months; 13 patients were alive without cancer at mean 20.3 ± 7.2 months follow-up. Actuarial 2-year overall survival was 93%. Compared with our pre-COVID IGABT program, overall mIGABT cost-saving in this cohort was USD 22,866. Prescribed dose covered at least 90% (D90) of the entire cervix and any residual cancer at time of BT (HRCTV_D90: high-risk clinical target volume) with 3-fractions of 8.5 Gy delivered over 24-h (22.8 ± 1.7 h). Total treatment time including CRT was 38 days. The mIGABT schedule was well tolerated and the entire cohort met EMBRACE recommended (EQD2: α/β10Gy) combined HRCTV_D90 coverage of 87.5 ± 3.7 Gy. Similarly, organ-at-risk (OAR) median: interquartile range D2cc constraints (EQD2: α/β3Gy) were EMBRACE compliant: bladder (65.9 Gy: 58.4-72.5 Gy), rectum (59.1 Gy: 55.7-61.8 Gy), and sigmoid colon (54.6 Gy: 50.3-58.9 Gy). ICRU recto-vaginal point dose was significantly higher (75.7 Gy) in our only case of severe (G4) pelvic toxicity.

CONCLUSIONS

This study demonstrated the utility of mIGABT and VMAT CRT in a small cohort with LACC. Loco-regional control was achieved in all cases with minimal emergent toxicity. Single insertion mIGABT was logistically efficient, cost-saving, and patient-centric during the COVID-19 pandemic.

A practical method to improve the performance of knowledge-based VMAT planning for endometrial and cervical cancer

PURPOSE

The aim of this work was to demonstrate a practical and effective method to improve the performance of RapidPlan (RP) model.

METHODS

203 consecutive clinical VMAT plans (P₀) for cervical and endometrial cancer were used to train an RP model (M₀). The plans were then reoptimized by M₀ to generate 203 new plans (P₁). Compared with P₀, 150 plans with a lower mean dose (MD) of bladder, rectum and PBM were selected from P₁ to configure a new RP model (M₁). A final RP model (M₂) was trained using plans in M₁ and the remaining 53 plans from P₁ (excluding OARs with worse MD) and the corresponding plans from P₀ (only including OARs with better MD). The models were validated on the mentioned 53 plans (closed-loop set) and 46 patient cohorts outside the training library (open-loop set). p < 0.05 was considered statistically significant.

RESULTS

For closed-loop validation, the difference of D_2%, D_98% and CI_95% between groups was of no statistical significance, the homogeneity index (HI) was lower in the groups of RP models (p < 0.05). The MD of all OARs decreased monotonically in the sequence of the clinical group, group M₀, M₁ and M₂, except the MD of bowel in M₁ and MD of LFH in M₂. Similarly, for open-loop validation, there was no significant difference in D_2%, D_98% and HI between groups, but CI_95% was larger in the clinical group (p < 0.05). The MD of all OARs decreased monotonically in the sequence of the clinical group, group M₀, M₁ and M₂, with the exception of bowel in M₁.

CONCLUSION

The practical method of incorporating plan data of better-sparing OARs from both the clinical VMAT plans and the re-optimized plans could further improve the performance of the RP model.

Radiotherapy resources in Africa: an International Atomic Energy Agency update and analysis of projected needs

The number of patients with cancer in Africa has been predicted to increase from 844 279 in 2012 to more than 1·5 million in 2030. However, many countries in Africa still lack access to radiotherapy as a part of comprehensive cancer care. The objective of this analysis is to present an updated overview of radiotherapy resources in Africa and to analyse the gaps and needs of the continent for 2030 in the context of the UN Sustainable Development Goals. Data from 54 African countries on teletherapy megavoltage units and brachytherapy afterloaders were extracted from the Directory for Radiotherapy Centres, an electronic, centralised, and continuously updated database of radiotherapy centres. Cancer incidence and future predictions were taken from the GLOBOCAN 2018 database of the International Agency for Research on Cancer. Radiotherapy need was estimated using a 64% radiotherapy utilisation rate, while assuming a machine throughput of 500 patients per year. As of March, 2020, 28 (52%) of 54 countries had access to external beam radiotherapy, 21 (39%) had brachytherapy capacity, and no country had a capacity that matched the estimated treatment need. Median income was an important predictor of the availability of megavoltage machines: US$1883 (IQR 914-3269) in countries without any machines versus $4485 (3079-12480) in countries with at least one megavoltage machine (p=0·0003). If radiotherapy expansion continues at the rate observed over the past 7 years, it is unlikely that the continent will meet its radiotherapy needs. This access gap might impact the ability to achieve the Sustainable Development Goals, particularly the target to reduce preventable, premature mortality by a third, and meet the target of the cervical cancer elimination strategy of 90% with access to treatment. Urgent, novel initiatives in financing and human capacity building are needed to change the trajectory and provide comprehensive cancer care to patients in Africa in the next decade.

Conventional 3D conformal radiotherapy and volumetric modulated arc therapy for cervical cancer: Comparison of clinical results with special consideration of the influence of patient- and treatment-related parameters

PURPOSE

Intensity-modulated radiotherapy (IMRT) for cervical cancer yields favorable results in terms of oncological outcomes, acute toxicity, and late toxicity. Limited data are available on clinical results with volumetric modulated arc therapy (VMAT). This study's purpose is to compare outcome and toxicity with VMAT to conventional 3D conformal radiotherapy (3DCRT), giving special consideration to the influence of patient- and treatment-related parameters on side effects.

MATERIALS AND METHODS

Patients with cervical cancer stage I-IVA underwent radiotherapy alone or chemoradiotherapy using 3DCRT (n = 75) or VMAT (n = 30). Survival endpoints were overall survival, progression-free survival, and locoregional control. The National Cancer Institute Common Terminology Criteria for Adverse Events and the Late Effects of Normal Tissues criteria were used for toxicity assessment. Toxicity and patient- and treatment-related parameters were included in a multivariable model.

RESULTS

There were no differences in survival rates between treatment groups. VMAT significantly reduced late small bowel toxicity (OR = 0.10, p = 0.03). Additionally, VMAT was associated with an increased risk of acute urinary toxicity (OR = 2.94, p = 0.01). A low body mass index (BMI; OR = 2.46, p = 0.03) and overall acute toxicity ≥grade 2 (OR = 4.17, p < 0.01) were associated with increased overall late toxicity.

CONCLUSION

We demonstrated significant reduction of late small bowel toxicity with VMAT treatment, an improvement in long-term morbidity is conceivable. VMAT-treated patients experienced acute urinary toxicity more frequently. Further analysis of patient- and treatment-related parameters indicates that the close monitoring of patients with low BMI and of patients who experienced relevant acute toxicity during follow-up care could improve late toxicity profiles.

Oncolytic adenoviral H101 synergizes with radiation in cervical cancer cells

BACKGROUND

A major challenge in cervical cancer radiotherapy is to tailor the radiation doses efficiently to both eliminate malignant cells and to reduce the side effects to normal tissue. Oncolytic adenoviral drug H101 is recently tested and approved for topical adjuvant treatment of several malignancies.

OBJECTIVE

This study is to evaluate the potential neoadjuvant radiotherapy benefits of H101 by testing the inhibitory function of H101 combined with radiation in different cervical cancer cells.

METHODS

Human cervical cancer cells C33a, SiHa, CaSki, and Hela were treated with varying concentrations of H101 alone or combined with radiation (2Gy or 4Gy). Cell viability and apoptosis were measured at indicated time intervals. HPV16 E6 and cellular p53 mRNA expression alteration were measured by qRT-PCR. RNA scope in-situ detect HPV E6 status. P53 protein alteration are detected by Western blot.

RESULTS

Cell viability and apoptosis show the combination of a high dose of H101 (MOI=1000, 10000) with radiation yielded a synergistic anti-cancer effect in all tested cervical cancer cell lines (P<0.05), with the greatest effect achieved in HPV negative C33a cells (P<0.05). Low HPV16 viral load SiHa cell was more sensitive to combination therapy than high HPV16 viral load CaSki cell (P<0.05). The combined treatment could reduce HPV16 E6 expression and increase cellular P53 level compared to radiation alone in SiHa and CaSki (P<0.05).

CONCLUSIONS

Oncolytic adenoviral H101 effectively enhances the antitumor efficacy of radiation in cervical cancer cells and may serve as a novel combination therapy for cervical cancer.

A Cost-Utility Analysis of Magnetic Resonance (MR) Guided Brachytherapy Versus Two-Dimensional and Computed Tomography (CT) Guided Brachytherapy for Locally Advanced Cervical Cancer

PURPOSE

The standard treatment for locally advanced cervical cancer is external beam radiation therapy and concurrent cisplatin followed by brachytherapy. Traditionally, 2-dimensional brachytherapy (2DBT) or computed tomography guided brachytherapy (CTgBT) has been used, but magnetic resonance guided brachytherapy (MRgBT) improves clinical outcomes and has become the new standard of care. This cost-utility analysis was undertaken to compare MRgBT to CTgBT and 2DBT.

METHODS AND MATERIALS

A Markov model was constructed to evaluate the cost-utility from the perspective of the public health care payer in Ontario. Treatment effectiveness, expressed as quality-adjusted life years, and costs, expressed in 2016 Canadian dollars, were evaluated for MRgBT, CTgBT, and 2DBT. Results were reported as incremental cost-effectiveness ratios for all patients and separately for low and high-risk subgroups. Sensitivity analyses were performed to assess the impact of uncertainty in model parameters.

RESULTS

MRgBT improved tumor control, reduced side effects, and was less costly compared with either CTgBT or 2DBT for all patients and in low- and high-risk prognostic subgroups separately. Sensitivity analysis supported the robustness of the findings and identified the cost of treating cancer recurrence to be the single most influential model parameter.

CONCLUSIONS

MRgBT is more effective and less costly than CTgBT or 2DBT by avoiding downstream costs of treating cancer recurrence and managing side effects. These findings will assist health care providers and policymakers with future infrastructure and human resource planning to ensure optimal care of women with this disease.

Targeting of β-Catenin Reverses Radioresistance of Cervical Cancer with the PIK3CA-E545K Mutation

This study aims to explore whether E545K, the most common hotspot mutation of PIK3CA in cervical cancer, confers radioresistance to cervical cancer cells, to demonstrate the underling mechanism, and to develop the effective targets. SiHa and MS751 cells with PIK3CA-WT and PIK3CA-E545K were established by lentiviral transfection. The radiosensitivity was assessed by colony formation, cell cycle, cell apoptosis, DNA damage, and repair assay. The growth and immunohistochemical assay of xenograft tumor-related toxicity were evaluated in vivo It was indicated that more cells with PIK3CA-E545K arrested in S phase. Irradiation (IR) led to more survival percentage, less apoptosis, fewer pH2A.X foci, and higher expression of Chk1/2 in SiHa and MS751 cells bearing PIK3CA-E545K. Mechanically, AKT/GSK3β/β-catenin pathway was highly activated, and more β-catenin was found accumulated in nucleus in cells with PIK3CA-E545K after IR. Furthermore, targeting β-catenin by shRNA or XAV939 enhanced IR sensitivity in cells with PIK3CA-WT and PIK3CA-E545K, whereas it was more notably in the latter. β-Catenin shRNA and XAV939 increased IR-mediated inhibition of colony formation with highly activated p53/bcl2/bax pathway. XAV939 enhanced IR-caused apoptosis, DNA damage, overcame S-phase arrest, DNA repair and reversed β-catenin nuclear accumulation in MS751 cells with PIK3CA-E545K. In vivo, XAV939 enhanced the radiosensitivity of cervical cancer xenografts with PIK3CA-E545K with invisible viscera toxicity. The findings demonstrate that cervical cancer cells with PIK3CA-E545K are resistant to IR by enhancing the expression and nuclear accumulation of β-catenin. Targeting β-catenin reverses the radioresistance, which suggests possible areas for preclinical research on β-catenin inhibition for strengthening the radiosensitivity of cervical cancer.

Lives and Economic Loss in Brazil due to Lack of Radiotherapy Access in Cervical Cancer: A Cost-Effectiveness Analysis

AIMS

Among all malignancies, the use of radiotherapy incurs the highest survival benefit within cervical cancers. Radiotherapy, however, remains underutilised for cervical cancers within the Brazilian public health system (BPHS). The objective of this study was to estimate the potential health and monetary benefits for universal access to radiotherapy and chemoradiotherapy (CRT) for untreated cervical cancer patients in the BPHS.

MATERIALS AND METHODS

Using 2016 data on Brazilian cervical cancer incidence and availability of radiotherapy/CRT in the BPHS, the number of cancer deaths due to radiotherapy/CRT underutilisation was estimated. The incremental effectiveness was calculated by life-year gain. The indirect costs from mortality-related productivity loss (MRPL) were estimated based on life expectancy, wage and labour force participation rate. MRPL was compared with direct medical costs after being adjusted to 2016 US dollars. This study was conducted from the payer's perspective; both costs and effectiveness were discounted at a rate of 3%. The incremental cost-effectiveness ratio (ICER) was calculated to determine the cost-effectiveness of radiotherapy for cervical cancer in Brazil. One-way sensitivity analyses were carried out to assess the robustness of the model.

RESULTS

The total number of life-years lost due to lack of universal access to radiotherapy and CRT per year were 27 199 and 31 627, respectively. The annual cost to match the radiotherapy gap was $10.5 million, with an additional cost of $3 million to close the CRT gap. The mean years of potential life lost per death was 20.5. The cost per life saved was $7942 for radiotherapy alone (ICER $388/life-year) and $8774 for CRT (ICER $429/life-year). MRPL due to shortage of radiotherapy and CRT were $59 million and $69 million, respectively.

CONCLUSION

Providing universal access to radiotherapy/CRT for cervical cancer patients in the BPHS is highly cost-effective and should be prioritised as an impactful public health initiative.

Scale-up of radiotherapy for cervical cancer in the era of human papillomavirus vaccination in low-income and middle-income countries: a model-based analysis of need and economic impact

BACKGROUND

Radiotherapy is standard of care for cervical cancer, but major global gaps in access exist, particularly in low-income and middle-income countries. We modelled the health and economic benefits of a 20-year radiotherapy scale-up to estimate the long-term demand for treatment in the context of human papillomavirus (HPV) vaccination.

METHODS

We applied the Global Task Force on Radiotherapy for Cancer Control investment framework to model the health and economic benefits of scaling up external-beam radiotherapy and brachytherapy for cervical cancer in upper-middle-income, lower-middle-income, and low-income countries between 2015 and 2035. We estimated the unique costs of external-beam radiotherapy and brachytherapy and included a specific valuation of women's caregiving contributions. Model outcomes life-years gained and the human capital and full income net present value of investment. We estimated the effects of stage at diagnosis, radiotherapy delivery system, and simultaneous HPV vaccination (75% coverage) up to a time horizon set at 2072.

FINDINGS

For the period from 2015 to 2035, we estimated that 9·4 million women in low-income and middle-income countries required treatment with external-beam radiotherapy, of which 7·0 million also required treatment with brachytherapy. Incremental scale-up of radiotherapy in these countries from 2015 to meet optimal radiotherapy demand by 2035 yielded 11·4 million life-years gained, $59·3 billion in human capital net present value (-$1·5 billion in low-income, $19·9 billion in lower-middle-income, and $40·9 billion in upper-middle-income countries), and $151·5 billion in full income net present value ($1·5 billion in low-income countries, $53·6 billion in lower-middle-income countries, and $96·4 billion in upper-middle-income countries). Benefits increased with advanced stage of cervical cancer and more efficient scale up of radiotherapy. Bivalent HPV vaccination of 12-year-old girls resulted in a 3·9% reduction in incident cases from 2015-2035. By 2072, when the first vaccinated cohort of girls reaches 70 years of age, vaccination yielded a 22·9% reduction in cervical cancer incidence, with 38·4 million requiring external-beam radiotherapy and 28·8 million requiring brachytherapy.

INTERPRETATION

Effective cervical cancer control requires a comprehensive strategy. Even with HPV vaccination, radiotherapy treatment scale-up remains essential and produces large health benefits and a strong return on investment to countries at different levels of development.

FUNDING

None.

The population benefit of evidence-based radiotherapy: 5-Year local control and overall survival benefits

BACKGROUND

To describe the population benefit of radiotherapy in a high-income setting if evidence-based guidelines were routinely followed.

METHODS

Australian decision tree models were utilized. Radiotherapy alone (RT) benefit was defined as the absolute proportional benefit of radiotherapy compared with no treatment for radical indications, and of radiotherapy over surgery alone for adjuvant indications. Chemoradiotherapy (CRT) benefit was the absolute incremental benefit of concurrent chemoradiotherapy over RT. Five-year local control (LC) and overall survival (OS) benefits were measured. Citation databases were systematically queried for benefit data. Meta-analysis and sensitivity analysis were performed.

FINDINGS

48% of all cancer patients have indications for radiotherapy, 34% curative and 14% palliative. RT provides 5-year LC benefit in 10.4% of all cancer patients (95% Confidence Interval 9.3, 11.8) and 5-year OS benefit in 2.4% (2.1, 2.7). CRT provides 5-year LC benefit in an additional 0.6% of all cancer patients (0.5, 0.6), and 5-year OS benefit for an additional 0.3% (0.2, 0.4). RT benefit was greatest for head and neck (LC 32%, OS 16%), and cervix (LC 33%, OS 18%). CRT LC benefit was greatest for rectum (6%) and OS for cervix (3%) and brain (3%). Sensitivity analysis confirmed a robust model.

INTERPRETATION

Radiotherapy provides significant 5-year LC and OS benefits as part of evidence-based cancer care. CRT provides modest additional benefits.

Cancer Deaths due to Lack of Universal Access to Radiotherapy in the Brazilian Public Health System

AIMS

Radiotherapy plays a fundamental role in the treatment of cancer. Currently, the Brazilian public health system cannot match the national radiotherapy demand and many patients requiring radiotherapy are never exposed to this treatment. This study estimated the number of preventable deaths in the public health system if access to radiotherapy was universal.

MATERIALS AND METHODS

Incidence rates for the year 2016 provided by Instituto Nacional de Cancer were used in this analysis. The number of untreated patients requiring radiotherapy was obtained through the difference between the total number of patients requiring radiotherapy and the total amount of delivered radiotherapy treatments in the public health system. The number of deaths for the three most common cancers in each gender due to radiotherapy shortage was calculated. Initially, the total number of patients per cancer type was divided in stages using Brazilian epidemiological data. Subsequently, previously published tree arm diagrams were used to define the rate of patients requiring radiotherapy in each specific clinical setting. Finally, the clinical benefit of radiotherapy in overall survival was extracted from studies with level 1 evidence.

RESULTS

Over 596 000 cancer cases were expected in Brazil in 2016. The public health system covers more than 75% of the Brazilian population and an estimated 111 432 patients who required radiotherapy in 2016 did not receive this treatment. Breast, colorectal and cervix cancers are the most frequent malignant tumours in women and prostate, lung and colorectal in men. The number of deaths due to a radiotherapy shortage in the year 2016 for these types of cancer were: (i) breast: 1011 deaths in 10 years; (ii) cervix: 2006 deaths in 2 years; (iii) lung: 1206 deaths in 2 years; (iv) prostate, intermediate risk: 562 deaths in 13 years; high risk: 298 deaths in 10 years; (v) colorectal: 0 deaths, as radiotherapy has no proven benefit in overall survival.

CONCLUSION

Thousands of cancer patients requiring radiotherapy do not have access to this treatment in the Brazilian public health system. The shortage of radiotherapy has a significant detrimental effect on cancer survival; over 5000 deaths would probably be prevented in the most common cancer types if radiotherapy access was universal.

The Benefits of Providing External Beam Radiotherapy in Low- and Middle-income Countries

More than half of all cancer diagnoses worldwide occur in low- and middle-income countries (LMICs) and the incidence is projected to rise substantially within the next 20 years. Radiotherapy is a vital, cost-effective treatment for cancer; yet there is currently a huge deficit in radiotherapy services within these countries. The aim of this study was to estimate the potential outcome benefits if external beam radiotherapy was provided to all patients requiring such treatment in LMICs, according to the current evidence-based guidelines. Projected estimates of these benefits were calculated to 2035, obtained by applying the previously published Collaboration for Cancer Outcomes, Research and Evaluation (CCORE) demand and outcome benefit estimates to cancer incidence and projection data from the GLOBOCAN 2012 data. The estimated optimal radiotherapy utilisation rate for all LMICs was 50%. There were about 4.0 million cancer patients in LMICs who required radiotherapy in 2012. This number is projected to increase by 78% by 2035, a far steeper increase than the 38% increase expected in high-income countries. National radiotherapy benefits varied widely, and were influenced by case mix. The 5 year population local control and survival benefits for all LMICs, if radiotherapy was delivered according to guidelines, were estimated to be 9.6% and 4.4%, respectively, compared with no radiotherapy use. This equates to about 1.3 million patients who would derive a local control benefit in 2035, whereas over 615 000 patients would derive a survival benefit if the demand for radiotherapy in LMICs was met. The potential outcome benefits were found to be higher in LMICs. These results further highlight the urgent need to reduce the gap between the supply of, and demand for, radiotherapy in LMICs. We must attempt to address this 'silent crisis' as a matter of priority and the approach must consider the complex societal challenges unique to LMICs.

Clinical development of new drug-radiotherapy combinations

In countries with the best cancer outcomes, approximately 60% of patients receive radiotherapy as part of their treatment, which is one of the most cost-effective cancer treatments. Notably, around 40% of cancer cures include the use of radiotherapy, either as a single modality or combined with other treatments. Radiotherapy can provide enormous benefit to patients with cancer. In the past decade, significant technical advances, such as image-guided radiotherapy, intensity-modulated radiotherapy, stereotactic radiotherapy, and proton therapy enable higher doses of radiotherapy to be delivered to the tumour with significantly lower doses to normal surrounding tissues. However, apart from the combination of traditional cytotoxic chemotherapy with radiotherapy, little progress has been made in identifying and defining optimal targeted therapy and radiotherapy combinations to improve the efficacy of cancer treatment. The National Cancer Research Institute Clinical and Translational Radiotherapy Research Working Group (CTRad) formed a Joint Working Group with representatives from academia, industry, patient groups and regulatory bodies to address this lack of progress and to publish recommendations for future clinical research. Herein, we highlight the Working Group's consensus recommendations to increase the number of novel drugs being successfully registered in combination with radiotherapy to improve clinical outcomes for patients with cancer.

Hyperthermia and radiotherapy with or without chemotherapy in locally advanced cervical cancer: a systematic review with conventional and network meta-analyses

PURPOSE

A systematic review with conventional and network meta-analyses (NMA) was conducted to examine the outcomes of loco-regional hyperthermia (HT) with radiotherapy (RT) and/or chemotherapy (CT) in locally advanced cervix cancer, IIB-IVA (LACC).

METHODS AND MATERIALS

A total of 217 abstracts were screened from five databases and reported as per PRISMA guidelines. Only randomised trials with HT and RT ± CT were considered. The outcomes evaluated were complete response (CR), long-term loco-regional control (LRC), patients alive, acute and late grade III/IV toxicities.

RESULTS

Eight articles were finally retained. Six randomised trials with HTRT (n = 215) vs. RT (n = 212) were subjected to meta-analysis. The risk difference for achieving CR and LRC was greater by 22% (p < .001) and 23% (p < .001), respectively, with HTRT compared to RT. A non-significant survival advantage of 8.4% with HTRT was noted with no differences in acute or late toxicities. The only HTCTRT vs. RT trial documented a CR of 83.3% vs. 46.7% (risk difference: 36.7%, p = .001). No other end points were reported. Bayesian NMA, incorporating 13 studies (n = 1000 patients) for CR and 12 studies for patients alive (n = 807 patients), comparing HTCTRT, HTRT, CTRT and RT alone, was conducted. The pairwise comparison of various groups showed that HTRTCT was the best option for both CR and patient survival. This was also evident on ranking treatment modalities based on the "surface under cumulative ranking" values.

CONCLUSIONS

In LACC, HTRT demonstrates a therapeutic advantage over RT without significant acute or late morbidities. On NMA, HTCTRT appears promising, but needs further confirmation through prospective randomised trials.

A Population-based Model of Local Control and Survival Benefit of Radiotherapy for Lung Cancer

AIMS

To estimate the population-based locoregional control and overall survival benefits of radiotherapy for lung cancer if the whole population were treated according to evidence-based guidelines. These estimates were based on a published radiotherapy utilisation (RTU) model that has been used to estimate the demand and planning of radiotherapy services nationally and internationally.

MATERIALS AND METHODS

The lung cancer RTU model was extended to incorporate an estimate of benefits of radiotherapy alone, and of radiotherapy in conjunction with concurrent chemotherapy (CRT). Benefits were defined as the proportional gains in locoregional control and overall survival from radiotherapy over no radiotherapy for radical indications, and from postoperative radiotherapy over surgery alone for adjuvant indications. A literature review (1990-2015) was conducted to identify benefit estimates of individual radiotherapy indications and summed to estimate the population-based gains for these outcomes. Model robustness was tested through univariate and multivariate sensitivity analyses.

RESULTS

If evidence-based radiotherapy recommendations are followed for the whole lung cancer population, the model estimated that radiotherapy alone would result in a gain of 8.3% (95% confidence interval 7.4-9.2%) in 5 year locoregional control, 11.4% (10.8-12.0%) in 2 year overall survival and 4.0% (3.6-4.4%) in 5 year overall survival. For the use of CRT over radiotherapy alone, estimated benefits would be: locoregional control 1.7% (0.8-2.4%), 2 year overall survival 1.7% (0.5-2.8%) and 5 year overall survival 1.2% (0.7-1.9%).

CONCLUSIONS

The model provided estimates of radiotherapy benefit that could be achieved if treatment guidelines are followed for all cancer patients. These can be used as a benchmark so that the effects of a shortfall in the utilisation of radiotherapy can be better understood and addressed. The model can be adapted to other populations with known epidemiological parameters to ensure the planning of equitable radiotherapy services.

Expanding global access to radiotherapy

Radiotherapy is a critical and inseparable component of comprehensive cancer treatment and care. For many of the most common cancers in low-income and middle-income countries, radiotherapy is essential for effective treatment. In high-income countries, radiotherapy is used in more than half of all cases of cancer to cure localised disease, palliate symptoms, and control disease in incurable cancers. Yet, in planning and building treatment capacity for cancer, radiotherapy is frequently the last resource to be considered. Consequently, worldwide access to radiotherapy is unacceptably low. We present a new body of evidence that quantifies the worldwide coverage of radiotherapy services by country. We show the shortfall in access to radiotherapy by country and globally for 2015-35 based on current and projected need, and show substantial health and economic benefits to investing in radiotherapy. The cost of scaling up radiotherapy in the nominal model in 2015-35 is US$26·6 billion in low-income countries, $62·6 billion in lower-middle-income countries, and $94·8 billion in upper-middle-income countries, which amounts to $184·0 billion across all low-income and middle-income countries. In the efficiency model the costs were lower: $14·1 billion in low-income, $33·3 billion in lower-middle-income, and $49·4 billion in upper-middle-income countries-a total of $96·8 billion. Scale-up of radiotherapy capacity in 2015-35 from current levels could lead to saving of 26·9 million life-years in low-income and middle-income countries over the lifetime of the patients who received treatment. The economic benefits of investment in radiotherapy are very substantial. Using the nominal cost model could produce a net benefit of $278·1 billion in 2015-35 ($265·2 million in low-income countries, $38·5 billion in lower-middle-income countries, and $239·3 billion in upper-middle-income countries). Investment in the efficiency model would produce in the same period an even greater total benefit of $365·4 billion ($12·8 billion in low-income countries, $67·7 billion in lower-middle-income countries, and $284·7 billion in upper-middle-income countries). The returns, by the human-capital approach, are projected to be less with the nominal cost model, amounting to $16·9 billion in 2015-35 (-$14·9 billion in low-income countries; -$18·7 billion in lower-middle-income countries, and $50·5 billion in upper-middle-income countries). The returns with the efficiency model were projected to be greater, however, amounting to $104·2 billion (-$2·4 billion in low-income countries, $10·7 billion in lower-middle-income countries, and $95·9 billion in upper-middle-income countries). Our results provide compelling evidence that investment in radiotherapy not only enables treatment of large numbers of cancer cases to save lives, but also brings positive economic benefits.

Evaluation of planning aims and dose prescription in image-guided adaptive brachytherapy and radiochemotherapy for cervical cancer: Vienna clinical experience in 225 patients from 1998 to 2008

BACKGROUND

To assess planning aims (PAs) and dose prescription in image-guided adaptive brachytherapy (IGABT) of cervical cancer and investigate potential impact on clinical outcome.

MATERIAL AND METHODS

Our study population consists of 225 consecutive cervical cancer patients (FIGO stages IB-IVA) treated between 1998 and 2008 at the Medical University of Vienna by external beam radiotherapy (EBRT) ± chemotherapy and IGABT. For this retrospective study, patients were stratified into two treatment groups: PA+ group, all dose constraints fulfilled for prescription; PA-, one or more dose constraints not fulfilled for prescription. The following dose constraints (EBRT+ IGABT) were applied: clinical target volume (CTV)HR D90 ≥ 85 Gy, D2cm3 Rectum < 70 Gy, D2cm3 Bladder < 90 Gy. Differences in patient, tumor and treatment characteristics and clinical outcome (event: local failure or grade 3 + 4 toxicity) were compared between Group 1 and 2. Further, the impact of learning period (1998-2000) and protocol period (2001-2008) on the fulfillment of PAs for dose prescription and clinical outcome was analyzed.

RESULTS

In the PA+ group there were 77 (34%) and in the PA- group 148 (66%) patients. In the PA- group, CTVHR D90 < 85 Gy was prescribed in 82 patients, D2cm3 bladder > 90 Gy was prescribed in 80 patients and D2cm3 Rectum > 70 Gy in 60 patients. Fulfillment of the PA for dose prescription improved from 4% in the learning period to 48% in the protocol period. The five-year event-free interval was 64% in the learning period and 84% in the protocol period (p = 0.008).

CONCLUSION

Fulfillment of all PAs for dose prescription is challenging - especially in patients with more advanced tumors. However, with growing experience fulfillment of PA for dose prescription can be significantly increased (learning and protocol period). Such increase in fulfilling PA for dose prescription is followed by a significant improvement in clinical outcome.