Primer consenso español sobre el uso de la radioterapia intraoperatoria en el cáncer de mama. Conclusiones del panel de expertos / First Spanish consensus on the use of intraoperative radiotherapy in breast cancer. Conclusions of the expert panel

Introducción: la publicación de ensayos aleatorizados con resultados a largo plazo ha demostrado que la radioterapia intraoperatoria (RIO) en cáncer de mama en estadio precoz puede ser una alternativa terapéutica en casos bien seleccionados. En el presente trabajo se presentan los resultados del Primer Consenso de Radioterapia Intraoperatoria en Cáncer de Mama realizado de manera multidisciplinar en España. Material y método: se hizo una revisión sistemática de la literatura y se invitó a todos los oncólogos radioterápicos y cirujanos expertos en RIO en cáncer de mama de España a participar en el consenso. Se aplico la siguiente metodología en 2 fases: a) la creación de un grupo de trabajo y la revisión de la evidencia; b) la realización de la encuesta y generación de recomendaciones consensuadas. Resultados: han participado un total 95,65% de los centros que actualmente utilizan esta técnica en cáncer de mama y que fueron invitados. Los expertos estuvieron de acuerdo en el uso de RIO exclusiva en cáncer de mama en aquellas pacientes mayores de 60 años y por encima de 50 años posmenopáusicas, con carcinoma ductal infiltrante o subtipos histológicos favorables, sin invasión linfovascular, tumores menores o iguales a 25 mm, márgenes de resección libres y receptores hormonales positivos. La utilización de RIO como rescate de recidiva local después de la irradiación externa alcanzó un nivel de consenso muy fuerte. Conclusión: el presente consenso pretende establecer las guías respecto a las indicaciones de RIO exclusiva o como sobreimpresión anticipada y ser una ayuda para la toma conjunta de decisiones. (AU)

Introduction: The publication of randomized trials with long-term results has demonstrated that intraoperative radiation therapy (IORT) in early-stage breast cancer can be a therapeutic alternative for well-selected cases. This paper present work presents the results of the first multidisciplinary consensus on IORT in breast cancer carried out in Spain. Materials and methods: A systematic literature review was conducted, and all radiation oncologists and surgeons with expertise in IORT for breast cancer in Spain were invited to participate in the consensus. The following methodology was employed in two phases: a) creation of a working group and review of the evidence; b) conduct of the survey and generation of consensus recommendations. Results: A total of 95.65% of the invited centers currently utilizing this technique in breast cancer participated. The experts agreed on the use of exclusive intraoperative radiation therapy in breast cancer for patients above 60 years of age and above 50 years postmenopausal, with invasive ductal carcinoma or favorable histological subtypes, no lymphovascular invasion, tumors less than or equal to 25 mm, clear surgical margins, and positive hormone receptor. The use of IORT as salvage surgery for local recurrence after external irradiation achieved a very strong consensus level. Conclusion: The present consensus aims to establish guidelines regarding the indications for exclusive IORT or as an early boost, and to serve as an aid for joint decision-making. (AU)

Tumor Bed Boost Radiotherapy in the Conservative Treatment of Breast Cancer: A Review of Intra-Operative Techniques and Outcomes.

Conservative surgery is the preferred treatment in the management of breast cancer followed by adjuvant whole-breast irradiation. Since the tumor bed is the main site of relapse, boost doses are conveniently administered according to risk factors for local relapse to increase the efficacy of the treatment. The benefit of a radiation boost is well established and it can be performed by several techniques like brachytherapy, external radiation or intraoperative radiotherapy. Greater precision in localizing the tumor cavity, immediacy and increased biological response are the main advantages of intraoperative boost irradiation. This modality of treatment can be performed by means of mobile electron accelerators or low-photon X-ray devices. There is a lot of research and some published series analyzing the results of the use of an intraoperative boost as an adjuvant treatment, after neoadjuvant systemic therapy and in combination with some reconstructive surgeries. This review discusses advantages of intraoperative radiotherapy and presents the main results of a boost in terms of local control, survival, tolerance and cosmesis.

Time trends and survival of marginal zone lymphoma over 25 years in Girona, Spain (1994-2018).

OBJECTIVE: To analyze the incidence, incidence trends, and survival of marginal zone lymphomas (MZLs) in Girona and to describe these indicators based on the location in the case of extranodal MZLs. METHODS: Population-based study of MZL collected in the Girona Cancer Registry, 1994-2018. Sociodemographic data, tumor location, and stage were obtained from clinical records. Crude (CR) and age-adjusted (ASRE ) incidence rates expressed per 100,000 person-years (p-y) were calculated. Joinpoint regression models were used for the trend analysis according to the MZL group. Five-year observed and net survival were analyzed. RESULTS: A total of 472 MZLs were included, 44 (9.3%) were nodal, 288 (61.0%) extranodal, 122 (25.9%) splenic, and the rest (n = 18) MZL, NOS. The CR for the MZL was 2.89 × 100,000 p-y (95% CI: 2.63-3.15), the ASRE was 3.26 × 100,000 p-y (95% CI: 2.97-3.57), and the annual percentage change (APC) was 1.6 (95% CI: 0.5-2.7). The ASRE for nodal MZL was 0.30 × 100,000 p-y (95% CI: 0.22-0.41) and showed an APC of 2.9% (95% CI: -16.4-26.6). For extranodal MZL, the ASRE was 1.98 × 100,000 p-y (95% CI: 1.76-2.23) and the APC was -0.4 (95% CI: -2.0-1.2). The most frequent locations of this type of MZL were the gastric (35.4%), skin (13.2%), and respiratory system (11.8%). The ASRE of the splenic MZL was 0.85 (95% CI: 0.71-1.02) with an APC of 12.8 (95% CI: 2.5-24.0). The 5-year net survival of MZL was 82.1% (95% CI: 76.3-86.5). CONCLUSIONS: This study reveals differences in the incidence and trend of the incidence of MZL according to the subgroup, showing a significant increase in the overall MZL mainly due to splenic MZL type.

Effectiveness and safety of intraoperative radiotherapy (IORT) with low-energy X-rays (INTRABEAM) for accelerated partial breast irradiation (APBI)

PurposeTo evaluate treatment outcomes in patients with early-stage breast cancer (ESBC) treated with targeted intraoperative radiation therapy (IORT) administered as accelerated partial breast irradiation (APBI).MethodsBetween December 2014 and May 2019, 50 patients diagnosed with ESBC were treated with a 50 kilovoltage (kV) X-ray source with a single dose of 20 Gy using the Intrabeam® radiotherapy delivery system. All patients were followed prospectively to assess local control (LC), disease-free survival (DFS), cancer-specific survival (CSS), overall survival (OS), radiation-induced toxicity, and cosmetic outcomes. We also evaluated the prognostic implications of the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR).ResultsMedian follow-up was 53 months. Mean patient age was 70 years. The mean duration of radiation delivery was 22.25 min. Two patients developed a recurrence. One death was recorded. Elevated pretreatment NLR levels were a significant risk factor for mortality (p = 0.0026). The most common treatment-related toxicities were breast induration (30%) and seroma (18%). Five-year LC, DFS, CSS, and OS rates were 97.1%, 93.9%, 100%, and 94.4%, respectively. Cosmesis was excellent or good in most cases (94%).ConclusionThese findings confirm the effectiveness of a single dose of 20 Gy of IORT with the Intrabeam device as APBI. The toxicity profile was good with excellent cosmesis. These results provide further support for the clinical use of APBI in well-selected patients. (AU)

Evidence-based guidelines for hypofractionated radiation in breast cancer: conclusions of the Catalan expert working group

IntroductionDaily, moderate hypofractionation has become standard treatment for breast cancer following breast-conserving surgery, although substantial variation exists in its use. This paper describes the generation of consensus-based recommendations for the utilisation of this therapy at the healthcare system level and compares these to American Society for Radiation Oncology (ASTRO) guidelines.Materials and methodsConsensus-based guidelines were developed in three steps, including a systematic literature review and involvement of radiation oncologists specialising in breast cancer in Catalonia: (a) creation of a working group and evidence review; (b) consideration of the levels of evidence and agreement on the formulation of survey questions; and (c) performance of survey and development of consensus-based recommendations. Results were compared to the ASTRO recommendations.ResultsConsensus was above 80% for 10 of the 14 survey items. Experts supported hypofractionated radiotherapy for all breast cancer patients aged 40 years or more; with invasive carcinoma and breast-conserving surgery; without radiation of lymph nodes; and regardless of the tumour size, histological grade, molecular subtype, breast size, laterality, other treatment characteristics, or need for a boost. Over half favoured its use in all situations, even where available scientific evidence is insufficient. The resulting recommendations and the quality of the evidence are comparable to those from ASTRO, despite some differences in the degree of consensus.ConclusionSpecialists agree that hypofractionation is the standard treatment for breast cancer following breast-conserving surgery, but some specific areas require a higher level of evidence before unequivocally extending indications. (AU)

Subclinical Left Ventricular Dysfunction Detected by Speckle-Tracking Echocardiography in Breast Cancer Patients Treated With Radiation Therapy: A Six-Month Follow-Up Analysis (MEDIRAD EARLY-HEART study).

Background: In the case of breast cancer (BC), radiotherapy (RT) helps reduce locoregional recurrence and BC-related deaths but can lead to cardiotoxicity, resulting in an increased risk of long-term major cardiovascular events. It is therefore of primary importance to early detect subclinical left ventricular (LV) dysfunction in BC patients after RT and to determine the dose-response relationships between cardiac doses and these events. Methods: Within the frame of the MEDIRAD European project (2017-2022), the prospective multicenter EARLY-HEART study (ClinicalTrials.gov Identifier: NCT03297346) included chemotherapy naïve BC women aged 40-75 years and treated with lumpectomy and adjuvant RT. Myocardial strain analysis was provided using speckle-tracking echocardiography performed at baseline and 6 months following RT. A global longitudinal strain (GLS) reduction >15% between baseline and follow-up was defined as a GLS-based subclinical LV dysfunction. Individual patient dose distributions were obtained using multi-atlas-based auto-segmentation of the heart. Dose-volume parameters were studied for the whole heart (WH) and left ventricle (LV). Results: The sample included 186 BC women (57.5 ± 7.9 years, 64% left-sided BC). GLS-based subclinical LV dysfunction was observed in 22 patients (14.4%). These patients had significantly higher cardiac exposure regarding WH and LV doses compared to patients without LV dysfunction (for mean WH dose: 2.66 ± 1.75 Gy versus 1.64 ± 0.96 Gy, p = 0.01). A significantly increased risk of subclinical LV dysfunction was observed with the increase in the dose received to the WH [ORs from 1.13 (V5) to 1.74 (Dmean); p <0.01] and to the LV [ORs from 1.10 (V5) to 1.46 (Dmean); p <0.01]. Based on ROC analysis, the LV-V5 parameter may be the best predictor of the short-term onset of subclinical LV dysfunction. Conclusion: These results highlighted that all cardiac doses were strongly associated with the occurrence of subclinical LV dysfunction arising 6 months after BC RT. Whether measurements of GLS at baseline and 6 months after RT combined with cardiac doses can early predict efficiently subclinical events occurring 24 months after RT remains to be investigated.

Effectiveness and safety of intraoperative radiotherapy (IORT) with low-energy X-rays (INTRABEAM®) for accelerated partial breast irradiation (APBI).

PURPOSE: To evaluate treatment outcomes in patients with early-stage breast cancer (ESBC) treated with targeted intraoperative radiation therapy (IORT) administered as accelerated partial breast irradiation (APBI). METHODS: Between December 2014 and May 2019, 50 patients diagnosed with ESBC were treated with a 50 kilovoltage (kV) X-ray source with a single dose of 20 Gy using the Intrabeam® radiotherapy delivery system. All patients were followed prospectively to assess local control (LC), disease-free survival (DFS), cancer-specific survival (CSS), overall survival (OS), radiation-induced toxicity, and cosmetic outcomes. We also evaluated the prognostic implications of the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR). RESULTS: Median follow-up was 53 months. Mean patient age was 70 years. The mean duration of radiation delivery was 22.25 min. Two patients developed a recurrence. One death was recorded. Elevated pretreatment NLR levels were a significant risk factor for mortality (p = 0.0026). The most common treatment-related toxicities were breast induration (30%) and seroma (18%). Five-year LC, DFS, CSS, and OS rates were 97.1%, 93.9%, 100%, and 94.4%, respectively. Cosmesis was excellent or good in most cases (94%). CONCLUSION: These findings confirm the effectiveness of a single dose of 20 Gy of IORT with the Intrabeam device as APBI. The toxicity profile was good with excellent cosmesis. These results provide further support for the clinical use of APBI in well-selected patients.

Evidence-based guidelines for hypofractionated radiation in breast cancer: conclusions of the Catalan expert working group.

INTRODUCTION: Daily, moderate hypofractionation has become standard treatment for breast cancer following breast-conserving surgery, although substantial variation exists in its use. This paper describes the generation of consensus-based recommendations for the utilisation of this therapy at the healthcare system level and compares these to American Society for Radiation Oncology (ASTRO) guidelines. MATERIALS AND METHODS: Consensus-based guidelines were developed in three steps, including a systematic literature review and involvement of radiation oncologists specialising in breast cancer in Catalonia: (a) creation of a working group and evidence review; (b) consideration of the levels of evidence and agreement on the formulation of survey questions; and (c) performance of survey and development of consensus-based recommendations. Results were compared to the ASTRO recommendations. RESULTS: Consensus was above 80% for 10 of the 14 survey items. Experts supported hypofractionated radiotherapy for all breast cancer patients aged 40 years or more; with invasive carcinoma and breast-conserving surgery; without radiation of lymph nodes; and regardless of the tumour size, histological grade, molecular subtype, breast size, laterality, other treatment characteristics, or need for a boost. Over half favoured its use in all situations, even where available scientific evidence is insufficient. The resulting recommendations and the quality of the evidence are comparable to those from ASTRO, despite some differences in the degree of consensus. CONCLUSION: Specialists agree that hypofractionation is the standard treatment for breast cancer following breast-conserving surgery, but some specific areas require a higher level of evidence before unequivocally extending indications.

Multicentre clinical radiotherapy audit in rectal cancer: results of the IROCA project.

PURPOSE: To perform a clinical audit to assess adherence to standard clinical practice for the diagnosis, treatment, and follow-up of patients undergoing radiotherapy for rectal cancer treatment in four European countries. MATERIALS AND METHODS: Multi-institutional, retrospective cohort study of 221 patients treated for rectal cancer in 2015 at six European cancer centres. Clinical indicators applicable to general radiotherapy processes were evaluated. All data were obtained from electronic medical records. RESULTS: The audits were performed in the year 2017. We found substantial inter-centre variability in adherence to standard clinical practices: 1) presentation of cases at departmental clinical sessions (range, 0-100%) or multidisciplinary tumour board (50-95%); 2) pretreatment MRI (61.5-100%) and thoracoabdominal CT (15.0-100%). Large inter-centre differences were observed in the mean interval between biopsy and first visit to the radiotherapy department (range, 21.6-58.6 days) and between the first visit and start of treatment (15.1-38.8 days). Treatment interruptions ≥ 1 day occurred in 43.9% (2.5-90%) of cases overall. Treatment compensation was performed in 2.1% of cases. Treatment was completed in the prescribed time in 55.7% of cases. CONCLUSIONS: This multi-institutional clinical audit revealed that most centres adhered to standard clinical practices for most of the radiotherapy processes-related variables assessed. However, the audit revealed marked inter-centre variability for certain quality indicators, particularly inconsistent record keeping. Multiple targets for improvement and/or harmonisation were identified, confirming the value of routine clinical audits to detect potential deviations from standard clinical practice.

Impact of non-adherence to radiotherapy on 1-year survival in cancer patients in Catalonia, Spain.

BACKGROUND: This study aims to assess the effects of non-adherence to external beam radiation therapy in cancer patients receiving treatment with a curative. METHODS: This retrospective cohort study collected health records data for all cancer patients treated with external beam radiotherapy with curative intent in 2016 in Catalonia, Spain. Adherence was defined as having received at least 90% of the total dose prescribed. A logistic regression model was used to assess factors related to non-adherence, and its association with one-year survival was evaluated using Cox regression. RESULTS: The final sample included 8721 patients (mean age 63.6 years): breast cancer was the most common tumour site (38.1%), followed by prostate and colon/rectum. Treatment interruptions prolonged the total duration of therapy in 70.7% of the patients, and 1.0% were non-adherent. Non-adherence was associated with advanced age, female gender, and some localization of primary tumour (head and neck, urinary bladder, and haematological cancers). The risk of death in non-adherent patients was higher than in adherent patients (hazard ratio [HR] 1.63, 95% confidence interval 0.97-2.74), after adjusting for the potential confounding effect of age, gender, tumour site and comorbidity. CONCLUSION: Non-adherence to radiotherapy, as measured by the received dose, is very low in our setting, and it may have an impact on one-year survival.

Early Detection of Cardiovascular Changes After Radiotherapy for Breast Cancer: Protocol for a European Multicenter Prospective Cohort Study (MEDIRAD EARLY HEART Study).

BACKGROUND: Breast cancer is the most common cancer among women, and radiotherapy plays a major role in its treatment. However, breast cancer radiotherapy can lead to incidental irradiation of the heart, resulting in an increased risk for a variety of heart diseases arising many years after radiotherapy. Therefore, identifying breast cancer patients at the highest risk for radiation-induced cardiac complications is crucial for developing strategies for primary and secondary prevention, which may contribute to healthy aging. There is still a need for precise knowledge on the relationship between radiation dose to specific cardiac structures and early subclinical cardiac changes and their occurrence over time that could finally lead to cardiac complications. OBJECTIVE: The MEDIRAD EARLY HEART study aims to identify and validate new cardiac imaging and circulating biomarkers of radiation-induced cardiovascular changes arising within first 2 years of breast cancer radiotherapy and to develop risk models integrating these biomarkers combined with precise dose metrics of cardiac structures based on three-dimensional dosimetry. METHODS: The EARLY HEART study is a multicenter, prospective cohort study in which 250 women treated for breast cancer and followed for 2 years after radiotherapy will be included. Women treated with radiotherapy without chemotherapy for a unilateral breast cancer and aged 40-75 years meet the inclusion criteria. Baseline and follow-up data include cardiac measurements based on two-dimensional speckle-tracking echocardiography, computed tomography coronary angiography, cardiac magnetic resonance imaging, and a wide panel of circulating biomarkers of cardiac injury. The absorbed dose will be evaluated globally for the heart and different substructures. Furthermore, the dose-response relationship will allow modeling the radiation-induced occurrence and evolution of subclinical cardiac lesions and biomarkers to develop prediction models. RESULTS: This study details the protocol of the MEDIRAD EARLY HEART study and presents the main limits and advantages of this international project. The inclusion of patients began in 2017. Preliminary results are expected to be published in 2019, and complete analysis should be published in 2021. CONCLUSIONS: The MEDIRAD EARLY HEART study will allow identifying the main cardiac imaging and blood-based determinants of radiation-induced cardiac injuries to better propose primary and secondary preventive measures in order to contribute to enhanced patient care and quality of life. TRIAL REGISTRATION: ClinicalTrials.gov NCT03297346; https://clinicaltrials.gov/ct2/show/NCT03297346 (Archived by WebCite at http://www.webcitation.org/72KS7MIUU). REGISTERED REPORT IDENTIFIER: RR1-10.2196/9906.

Understanding variations in the use of hypofractionated radiotherapy and its specific indications for breast cancer: A mixed-methods study.

BACKGROUND AND PURPOSE: Radiation oncology guidelines favour hypofractionated whole-breast radiotherapy (HWBRT) over more conventional schemes in the conservative treatment of breast cancer, but its adoption still varies in clinical practice. This study assessed the patterns of HWBRT adoption in Catalonia (Spain). MATERIAL AND METHODS: We used a mixed-methods approach based on an explanatory sequential design, first collecting and analysing quantitative data on HWBRT use (>2.5Gy per fraction) in 11 public radiotherapy centres (2005-2015) and then performing 25 semi-structured interviews with all department heads and reference radiation oncologist/s. RESULTS: Of the 34,859 patients fulfiling the study criteria over the study period, just 12% were hypofractionated, reaching a percentage of 29% in 2015 (p<0.001). Our analysis showed a narrowing age gap between patients receiving conventional fractionation and hypofractionation in centres leading adoption. However, there were important differences in clinicians' interpretation of evidence (e.g. regarding the perceived risk of long-term toxicity) and selection of patients for specific indications, both within and between departments. CONCLUSIONS: Differences observed in the rate of adoption of HWBRT could not be tackled only using a rational, evidence-based approach. Factors related to the management of radiotherapy departments play a major role in the diffusion of therapeutic strategies.

Feasibility, accuracy and prognosis of sentinel lymph node biopsy before neoadjuvant therapy in breast cancer. A prospective study.

BACKGROUND AND OBJECTIVE: It remains controversial whether sentinel lymph node biopsy (SLNB) should be performed before or after neoadjuvant therapy (NAT). We aimed to evaluate the feasibility and accuracy of SLNB before NAT at a single institution, and to determine its relation to patient prognosis. METHODS: A prospective study of T1c-T2-T3 N0 breast cancer patients, after ultrasound examination, who underwent SLNB prior to NAT. Overall, disease-specific and disease-free survival were calculated by Kaplan-Meier curves. RESULTS: SLNB before NAT was performed in 123 patients from December 2006 to May 2014. The identification rate was 100%. SLNB was positive in 42.3% of cases (27.6% macrometastases). NAT was chemotherapy in 88.6% of cases and endocrine-therapy in 11.4%. Lymphadenectomy was avoided in 72.4% of cases. Median follow-up was 40 months (range 8-100). Overall and disease-free survival was 90.2% and 88.6% respectively.SLN involvement was not related to patient outcome (p 0.72); however there were significant differences in survival according to molecular-like subtypes (p < 0.025) and NAT response (p < 0.0001). CONCLUSIONS: SLNB prior to NAT is an accurate method of axillary staging associated with a high identification rate. It avoided lymphadenectomy in more than 70% of patients. SLN involvement did not worsen the prognosis in our cohort.

The use of an interstitial boost in the conservative treatment of breast cancer: how to perform it routinely in a radiotherapy department.

PURPOSE: To demonstrate the utility of a boost with interstitial brachytherapy (BT) in breast-conserving therapy (BCT) by doing a thorough review of the literature and describing in detail our technique for delivering this boost. MATERIAL AND METHODS: Our department has been delivering the boost with interstitial BT since 1989, in most cases with rigid needles and a theoretical dosimetry. In the early years, we used low-dose-rate (LDR) with iridium-192 wires. The dose administered was 15 Gy if there were no risk factors for local relapse or 20-25 Gy in the presence of risk factors. The risk factors considered were the presence of a close margin (less than 10 mm) and an extensive intraductal component (more than 25%). After 2002, we switched to high-dose-rate (HDR); using the linear quadratic model we changed the low dose to 3 fractions of 4.5 Gy in the case of no risk factors for local relapse or to 3 fractions of 5 Gy in the presence of risk factors. RESULTS: In 79 consecutive boost patients treated in our department between 2010 and 2011, with a median follow-up of 46 months, the local control rate was 97.47%. With respect to cosmesis, fibrosis occurred in 17 cases (21.5%) and hyperpigmentation in 26 cases (32.9%). Our hospital's results are comparable in terms of local control and cosmesis to those of other authors. CONCLUSIONS: This educational article describes our department's boost technique with rigid needles and comments briefly on our results using this technique in a group of consecutively treated patients in our department. A review of the literature and the published results on local control and cosmesis is also described.