Is oligometastatic disease an applicable and useful concept in haematologic malignancies? A narrative review of radiation therapy standards, modern techniques, and innovations

PURPOSE

Haematologic malignancies are particular in that they can generally be cured, even when distant metastases are present at diagnosis, unlike solid malignancies. Systemic treatments, including chemotherapy, targeted therapies, and immunotherapy, are the standard of care with excellent results. The considerable progress made in the management of these diseases in the last 20years has redefined the role of radiation therapy as minor in many clinical situations. We propose a literature review of data, showing that radiation therapy still has a role in curative, salvage, and palliative therapy situations.

MATERIAL AND METHODS

A document and literature search was carried out in the following databases: Medline and ClinicalTrial.gov, for the terms "radiotherapy", "haematologic malignancies", "Hodgkin lymphoma", "non-Hodgkin lymphoma", "CAR T cells", "multiple myeloma", "solitary plasmocytoma", "intensity-modulated radiotherapy", "extracranial stereotactic body radiation therapy" and "proton therapy references".

RESULTS

Haemopathological malignancies include a wide range of diseases and radiation therapy indications have been assessed over the past 20years. Currently, radiation therapy is indicated for localized disease (solitary plasmocytoma), as an adjuvant (Hodgkin lymphoma), in palliative settings, or after systemic treatment in relapsed patients (chimeric antigen receptor [CAR] T-cells) with a low recurrence burden, which can therefore be considered "oligorecurrence". Radiation therapy, through total body irradiation, has important indications, thanks to its immunomodulatory and/or myeloablative effects. Moreover, recent technological developments have made possible significant improvement in safety, contributing to radiation therapy being positioned in the treatment strategy of several indications.

CONCLUSIONS

Given the effectiveness of systemic treatments in hematologic malignancies, the oligometastasis stage is of little importance. A curative intent after local radiation therapy, even advanced stage, is possible, both with residual disease for advanced Hodgkin lymphoma, aggressive non-Hodgkin lymphoma, or solitary plasmocytoma, and even without evidence of disease after chemotherapy for Hodgkin or non-Hodgkin lymphoma. The role of new treatments, such as CAR T cells, allows us to consider radiation therapy after systemic treatment of relapsed diseases with low volume recurrence, which can be considered oligorecurrence.

Effect of lethal total body irradiation on bone marrow chimerism, acute graft-versus-host disease, and tumor engraftment in mouse models: impact of different radiation techniques using low- and high-energy X-rays

PURPOSE

Effects of X‑ray energy levels used for myeloablative lethal total body irradiation (TBI) delivery prior to bone marrow transplantation (BMT) in preclinical mouse models were examined.

MATERIALS AND METHODS

In mouse models, single-fraction myeloablative TBI at a lethal dose was delivered using two different X‑ray devices, either low (160 kV cabinet irradiator) or high energy (6 MV linear accelerator), before semi-allogeneic hematopoietic stem-cell transplantation (HSCT) to ensure bone marrow (BM) chimerism, graft-versus-host disease (GVHD), and tumor engraftment. Recipient mice were clinically followed for 80 days after bone marrow transplantation (BMT). Flow cytometry was performed to assess donor chimerism and tumor engraftment in recipient mice.

RESULTS

Both X‑ray irradiation techniques delivered a 10 Gy single fraction of TBI, presented a lethal effect, and could allow near-complete early donor chimerism on day 13. However, low-energy irradiation increased T cells' alloreactivity compared to high-energy irradiation, leading to clinical consequences for GVHD and tumor engraftment outcomes. The alloreactive effect differences might be attributed to the distinction in inflammatory status of irradiated recipients at donor cell infusion (D0). Delaying donor cell administration (D1 after lethal TBI) attenuated T cells' alloreactivity and clinical outcomes in GVHD mouse models.

CONCLUSION

Different X‑ray irradiation modalities condition T cell alloreactivity in experimental semi-allogeneic BMT. Low-energy X‑ray irradiator induces a post-TBI inflammatory burst and exacerbates alloreactive reactions. This technical and biological information should be considered in interpreting GVHD/ graft-versus-leukemia effect results in mice experimental models of BMT.

Impact of Post-Mastectomy Radiotherapy on Cosmesis and Quality of Life after Deep Inferior Epigastric Perforator Flap Breast Reconstruction: A Single Institution Experience

PURPOSE/OBJECTIVE(S)

Immediate breast reconstruction (IBR) yields better cosmetic results and reduce psychological distress than delayed (DBR). Literature data showed better local cosmesis after reconstruction autologous flaps than prothesis. Our aim is to compare cosmetic results and quality of life (QoL) after PMRT delivered either after IBR or DBR with DIEP flap.

MATERIALS/METHODS

We reviewed files of 99 patients (100 DIEPs) treated in our department from January 2000 to December 2019. Patients were divided into 2 groups depending on the treatment sequence: IBR (n = 22) versus DBR (n = 78) followed by PMRT. All the patients had their DIEP flap by the same surgical team. All patients had cosmetic evaluation using Harvard/RTOG cosmesis grading scale. Fifty percent (32 in IBR and 14 in DBR group) of the patients responded to the QoL evaluation using auto questionnaires and BREAST-Q to evaluate breast specific HRQoL and satisfaction. The analysis of cosmetic scores was carried out with a Chi2 test and the analysis of QoL scores with a student test. Kaplan Meier (log-rank test) is used for recurrence-free and overall survival.

RESULTS

Median follow-up was 56 months. Median age of the patients was 48 (28-71). In terms of disease stage: T1-2 (52%), N0 (38%). 86% of the patients had chemotherapy either in neo-adjuvant (26%) or adjuvant (60%) settings. Radiation therapy (RT) delivered a total dose ranged between 45 Gy and 50 Gy using 1.8-2.5 Gy/per fraction. Supra-clavicular and internal mammary chain irradiation was performed in 67% and 33% of the patients respectively. After surgery, 15% had post-operative complications such as DIEP necrosis (n = 8) that delayed RT delivery. Among the 99 patients, 3 died from metastatic evolution and were not included in the cosmetic and QoL analyses. Local recurrence rate was slightly higher after DBR (12.5%) as compared to IBR (3.8%). Loco-regional and metastatic recurrence rates were 4.5% and 4.5% after IBR versus 1.3% and 9% after DBR (p = NS). Disease free and overall survival were 88% and 98% at 5y and 66% and 96% at 10y.Good-to-excellent results were observed in 57% in the IBR vs 67% in the DBR (p = 0.92). There was no impact of previous chemotherapy (p = 0.21), tobacco use at diagnosis (p = 0.27), diabetes (p = 0.86), RT timing (p = 0.53) and endocrine therapy administration (p = 0.67). QoL was evaluated with the BREAST-Q self-evaluation for 5 post operative items: psycho-social, physical, sexual well-being and satisfaction with breast and global cosmetic results. Out of the 99 patients, 46% had responded to the QoL evaluation. We found no statistical difference between the two groups for all the BREAST-Q evaluation items.

CONCLUSION

Our center is considered expert for DIEP reconstructions since its development in end of the nineties. Our data showed no impact PMRT using conventional fractionation (with mainly 1.8 Gy/fraction) on cosmetic results, QoL, and patients' satisfaction regardless of the timing of the breast reconstruction. Additional studies are in progress with updates.

Effect of Serelys Homme on the Incidence and Severity of Vasomotor Symptoms and Quality-of-Life Impairments in Patients Receiving Hormone Therapy and Radiation for Localized Prostate Cancer: Results of the ESCULAPE Phase 2 Prospective Study

Purpose

Androgen deprivation therapy (ADT) may cause vasomotor symptoms (VMS) including hot flushes and sweats, which affect quality of life (QoL). Serelys Homme is a nonhormonal and a natural origin product that could affect VMS in men undergoing ADT. We evaluated effectiveness and tolerance of Serelys Homme administration on VMS and QoL of patients undergoing combined ADT and radiation therapy for prostate cancer.

Methods and Materials

Between April 2017 and July 2019, 103 patients were screened, and 53 patients refused to participate in the study. Serelys Homme therapy consisted of a daily administration of 2 tablets for 6 months. Patients were evaluated with 4 questionnaires including the adapted Modified Rankin Scale (adapted-MRS), European Quality of Life 5 Dimensions 3 Level Version (EQ 5D3L), Functional Assessment of Cancer Therapy-Prostate (FACT-P), and Hot Flash Related Daily Interference Scale (HFRDIS) at day 0, day 90 (D90), and day 180 (D180). Statistical evaluation was performed using the Wilcoxon rank sign test. A 2-sided P < .05 was considered statistically significant.

Results

Among the 50 patients, 4 withdrew after inclusion. All patients (n = 46) received either postoperative or definitive radiation therapy combined with a short (n = 15) or long course (n = 31) of ADT. Serelys Homme administration significantly decreased the rate of patients who had ≥7 VMS and 3 to 6 VMS per day. The number of patients presenting with moderate or severe VMS was decreased at D90 (P = .005) and at D180 (P = .005). In addition, VMS duration was reduced at D90 (P = .002) and D180 (P < .001). Finally, at D90 and D180, 11.1% and 16.0% of patients, respectively, with initial severe or moderate VMS had a complete response without further symptoms. Among QoL parameters, fatigue decreased significantly. Effectiveness evaluated by doctors was rated as moderate or good to excellent VMS control in 20% and 60% of the patients, respectively. No side effects were recorded in the whole population.

Conclusions

This study demonstrated effectiveness and excellent tolerance of Serelys Homme. We observed a significant reduction of the frequency, duration, and intensity of hot flushes and sweats induced by ADT. Serelys Homme increased QoL scores. These encouraging results open the prospect to further studies and Serelys Homme use in patients undergoing ADT for prostate cancer.

Limited applicability and implementation of the international oncology treatments guidelines in low- and middle-income countries, an example from the Mediterranean area borders

The quality of cancer care in the modern era is based on a precise diagnosis and personalized therapy according to patients and their disease based on validated guidelines with a high level of evidence. During cancer patients' management, the objective is first to make an accurate diagnosis and then offer the best treatment, validated beforehand in a multidisciplinary board meeting, with the best benefit/risk ratio. In the context of many low- and middle-income countries, the limited available means do not allow an adequate offer, resulting in non-optimal patients' care. In addition, in many low- and middle-income countries, priority can be given to other types of disease than cancer, which may considerably reduce allocation of specific resources to cancer care. Thus, the limited availability of systemic therapy, radiotherapy machines, brachytherapy and technological development may come up against another difficulty, that of geographical distribution of the means in the countries or a lack of expertise due to insufficient training programs. For all these reasons, the implementation of the guidelines established in Western countries could be impossible for many low- and middle-income countries which, moreover, have to face a completely different epidemiology of cancers compared to developed countries. In this work, we will discuss through a few examples of common cancers on both borders of the Mediterranean area, the applicability of the guidelines and the limits of their implementation for optimal cancer care.

[The morbidity and mortality review meetings in radiotherapy departments: Procedure, implementation and prospects of the "Proust" French national project]

Radiation-induced acute and late toxicity depends on several parameters. The type, severity and duration of morbidity are mainly related to irradiated volume, total dose and its fractionation and the intrinsic radiosensitivity of the patients. The follow-up of these toxicities is essential. However, unlike many specialties, morbidity and mortality reviews procedures are not developed as part of quality governance programs in radiation therapy departments for the monitoring of toxicity which sometimes hinder the patients' quality of life. One French survey published within the framework of the project entitled Prospective Registration of Morbidity and Mortality, Individual Radiosensitivity and Radiation Technique (Proust), conclude that there was a lack of knowledge of morbidity and mortality reviews and considerable confusion between these reviews and other quality processes without perspective for the local morbidity and mortality reviews development in a large number of the participated centers. In this article, we will discuss the procedure of the "ideal morbidity and mortality reviews" and its implementation through a monocentric experience started in 2015. Thus, the Proust project is a unique opportunity to implement and standardize a national morbidity and mortality reviews implementation in radiation therapy departments by involving the French regions.

Interaction between Radiation Therapy and Targeted Therapies in HER2-Positive Breast Cancer: Literature Review, Levels of Evidence for Safety and Recommendations for Optimal Treatment Sequence

Purpose: Over the past twenty years, anti-HER2 targeted therapies have proven to be a revolution in the management of human epidermal growth receptor 2 (HER2)-positive breast cancers. Anti-HER2 therapies administered alone or in combination with chemotherapy have been specifically studied. Unfortunately, the safety of anti-HER2 therapies in combination with radiation remains largely unknown. Thus, we propose a literature review of the risks and safety of combining radiotherapy with anti-HER2 therapies. We will focus on the benefit/risk rationale and try to understand the risk of toxicity in early-stage and advanced breast cancer. Methods: Research was carried out on the following databases: PubMed, EMBASE, ClinicalTrial.gov, Medline, and Web of Science for the terms "radiotherapy", "radiation therapy", "radiosurgery", "local ablative therapy", and "stereotactic", combined with "trastuzumab", "pertuzumab", "trastuzumab emtansine", "TDM-1", "T-Dxd", "trastuzumab deruxtecan", "tucatinib", "lapatinib", "immune checkpoint inhibitors", "atezolizumab", "pembrolizumab", "nivolumab", "E75 vaccine", "interferon", "anti-IL-2", "anti-IL 12", and "ADC". Results: Association of radiation and monoclonal antibodies such as trastuzumab and pertuzumab (with limited data) seems to be safe, with no excess risk of toxicity. Preliminary data with radiation and of antibody-drug conjugate of trastuzumab combined cytotoxic (trastuzumab emtansine, trastuzumab deruxtecan), given the underlying mechanism of action, suggest that one must be particularly cautious with the association. The safety of the combination of a tyrosine kinase inhibitor (lapatinib, tucatinib) and radiation remains under-studied. The available evidence suggests that checkpoint inhibitors can be safely administrated with radiation. Conclusions: HER2-targeting monoclonal antibodies and checkpoint inhibitors can be combined with radiation, apparently with no excess toxicities. Caution is required when associating radiation with TKI and antibody drugs, considering the limited evidence.

Genomic Prostate Score: A New Tool to Assess Prognosis and Optimize Radiation Therapy Volumes and ADT in Intermediate-Risk Prostate Cancer

Genomic classifiers such as the Genomic Prostate Score (GPS) could help to personalize treatment for men with intermediate-risk prostate cancer (I-PCa). In this study, we aimed to evaluate the ability of the GPS to change therapeutic decision making in I-PCa. Only patients in the intermediate NCCN risk group with Gleason score 3 + 4 were considered. The primary objective was to assess the impact of the GPS on risk stratification: NCCN clinical and genomic risk versus NCCN clinical risk stratification alone. We also analyzed the predictive role of the GPS for locally advanced disease (≥pT3+) and the potential change in treatment strategy. Thirty patients were tested for their GPS between November 2018 and March 2020, with the median age being 70 (45-79). Twenty-three patients had a clinical T1 stage. Eighteen patients were classified as favorable intermediate risk (FIR) based on the NCCN criteria. The median GPS score was 39 (17-70). Among the 23 patients who underwent a radical prostatectomy, Gleason score 3 + 4 was found in 18 patients. There was a significant correlation between the GPS and the percentage of a Gleason grade 4 or higher pattern in the surgical sample: correlation coefficient r = 0.56; 95% CI = 0.2-0.8; p = 0.005. In this study, the GPS combined with NCCN clinical risk factors resulted in significant changes in risk group.

Financial fallout from the COVID-19 pandemic:Report from a high-volume academic neurosurgery

Background

The global healthcare system has been overwhelmed by the Coronavirus disease-2019 (COVID-19). In order to mitigate the risk of spread of the virus, most elective surgical procedures have been cancelled especially during the lockdown periods. The purpose of this study was to assess the financial impact of the COVID outbreak due to the supposed reduced workload from our neurosurgery department in 2020.

Methods

Number of neurosurgical procedures (NSP) within the Department of Neurosurgery and their associated estimated income were retrospectively reviewed globally and month wise from administrative records of billing in 2020 and 2019 based on the Diagnosis related group (DRG) and severity of illness (4 levels).

Results

Overall, 824 and 818 inpatient surgical procedures were performed in 2019 and 2020 respectively. The total estimate revenue generated from inpatient surgeries was moderately decreased (3%): 9 498 226.41 euros in 2020 versus 9 817 361.65 euros in 2019 without significant difference across DRG (P = 0.96) and severity of illness.

Conclusions

Our data suggests a moderate negative impact of the COVID-19 pandemic had on neurosurgical and financial activity. However, a more in-depth medico-economic analysis need to be performed to assess the real financial impact.

Curative intent Stereotactic Ablative Radiation Therapy (SABR) for treatment of lung oligometastases from head and neck squamous cell carcinoma (HNSCC): a multi-institutional retrospective study

OBJECTIVES

The aim of this retrospective study was to assess outcomes of SABR for metachronous isolated lung oligometastases from HNSCC.

METHODS

For patients who developed isolated, 1 or 2 lungs lesions (<5cm) consistent with metastases from HNSCC, the indication of SABR was validated in a multidisciplinary tumor board. All patients were monitored by CT or PET CT after SABR (Stereotactic Ablative Body Radiation) for HNSCC.

RESULTS

Between November 2007 and February 2018, 52 patients were treated with SABR for metachronous lung metastases. The median time from the treatment of the primary HNSCC to the development of lung metastases was 18 months (3-93). The cohort's median age was 65.5 years old (50-83). The vast majority (94.2%) received 60 Gy in three fractions. Forty-one patients (78.5%) presented a solitary lung metastasis, while 11 patients (21.5%) had two lung metastases. With a median follow-up of 45.3 months, crude local and metastatic control rates were 74 and 38%, respectively. 1 year and 2 year Overall Survival (OS) were 85.8 and 65.9%, respectively. The median OS was 46.8 months. About one-fourth of patients were retreated by SABR for distant pulmonary recurrence. The treatment was well tolerated with only one patient who reported ≥ grade 3 toxicity (1.9%).

CONCLUSION

In selected metastatic HNSCC patients, early detection and treatment of lung metastases with SABR is effective and safe. Prospective studies are required to validate this potential shift.

ADVANCES IN KNOWLEDGE

Patients with oligometastases and controlled primary HNSCC seem to benefit from metastasis directed therapies.

Radiation Therapy Delivery Challenges in Older Patients During Coronavirus Disease 2019 Pandemic

Purpose

The management of older patients in radiation therapy (RT) departments has been challenging in the context of the Coronavirus Disease 2019 (COVID-19) outbreak. We report our experience of RT adapted schedules or strategy changes in older patients during the COVID-19 pandemic.

Methods and Materials

Patients aged ≥75 years were recruited during weekly chart rounds. All were potentially eligible for a specific intervention to reduce the frequency of patients' visits to the hospital. The effect of deferring radiation and hypofractionation of RT schedules was assessed in terms of the number of courses initially planned and replanned during the lockdown.

Results

Twenty patients were identified during the official lockdown in France (March 17 to May 11). Median age was 78 years (75-95 years). Most patients were male (n = 12, 60%) being treated in the postoperative setting (n = 17, 85%). RT was delayed in 11 cases (55%) with hormonal therapy prescribed in 10 cases (50%). Altered RT fractionation was proposed for 5 cases (25%); combinations of altered fractionation and deferral of radiation were applied in 3 cases (15%). The number of radiation courses initially planned and replanned according to the pandemic context: 563 and 197, respectively (-62%; P < .001). None presented recurrence when RT was initiated, and no patient developed symptomatic COVID-19 infection.

Conclusions

In the context of the COVID-19 outbreak, individual risk-based radiation therapy seems to be safe. Systematic screening of patients for COVID-19 before starting radiation therapy is mandatory. In our department the oncogeriatrics expertise availability for daily practice was of great use during the pandemic. Other prospective studies are needed to validate such strategies in case of resurgence of similar outbreaks.

[Adjuvant and neoadjuvant radiotherapy in breast cancer: A literaure review and update on the state of the evidence in 2020]

Radiation therapy has benefited from many developments over the past 20 years. These developments are mainly linked to the technology, imaging and informatics evolutions which allow better targets definitions, ensure better organs-at-risk sparing and excellent reproducibility of treatments, with a perfect control of patient positioning. In breast cancer radiotherapy, the evolution was marked by the possibility of reducing the duration of treatments from 6-7 to 3-4 weeks by using hypofractionated regimens, or by further reducing the irradiation to one week when treatment is solely focalised to the tumour bed. This concept of accelerated partial breast irradiation has challenged the paradigm of the obligation to irradiate the whole breast after conservative surgery in all patients. In addition, the technical mastery of accelerated partial breast irradiation and the development of stereotactic radiotherapy techniques are currently contributing to the development of research projects in neoadjuvant settings. Thus, numerous ongoing studies are evaluating the impact of high-dose preoperative tumour irradiation, alone or in combination with systemic treatments, on biological tumor changes, on anti-tumour immunity, and on the pathologic complete response, which is considered as predictive of better long-term survival in some molecular breast cancer subtypes. In this review, we discuss all these developments which allow breast radiation therapy to enter the era of personalisation of treatments in oncology.

Radiation Therapy Department Reorganization during the Coronavirus Disease 2019 (COVID-19) Outbreak: Keys to Securing Staff and Patients During the First Weeks of the Crisis and Impact on Radiation Therapy Practice from a Single Institution Experience

PURPOSE

During the first weeks of the coronavirus disease 2019 (COVID-19) outbreak in France, it was necessary to clearly define organizational priorities in the radiation therapy (RT) departments. In this report, we focus on the urgent measures taken to reduce risk for both our staff and patients by reducing the number of patients receiving treatment.

METHODS AND MATERIALS

We reviewed the fractionation schemes for all patients in our department, including those receiving treatment and those soon to start treatment. Our goals were to (1) decrease the number of patients coming daily to the hospital for RT, (2) adapt our human resources to continue patients' care in the department, and (3) help to cover understaffed COVID-19 sectors of the hospital.

RESULTS

We identified 50 patients who were receiving treatment (n = 6), were going to start radiation after CT scan simulation (n = 41), or for whom the CT scan was pending (n = 3). The majority were women (64%) treated for breast cancer (54%). RT was delayed for 22 (44%) patients. The majority were offered hormone therapy as "waiting therapy." Hypofractionation was considered in 21 (42%) patients mainly with breast cancer (18 of 21, 86%). The number of courses initially planned and replanned as a result of the COVID-19 outbreak during the period of March 15 to May 31, 2020, were 1383 and 683, respectively, which represented a reduction of 50% (including delayed sessions) that allowed our reorganization process.

CONCLUSIONS

To conserve resources during the pandemic, we successfully reduced the number of patients receiving treatment in a proactive fashion and adapted our organization to minimize the risk of COVID-19 contamination. Departments across the world may benefit from this same approach.

[Stereotactic body radiation therapy for hepatocellular carcinoma: Results from a retrospective multicentre study]

PURPOSE

The purpose of this paper was to describe local control, overall survival, progression-free survival and toxicity of CyberKnife^®-based stereotactic body radiation therapy of hepatocellular carcinoma.

MATERIAL AND METHODS

Records of all the patients treated for hepatocellular carcinoma at the Eugene-Marquis cancer centre, Rennes and the Bretonneau hospital, Tours (France), between November 2010 and December 2016, were reviewed. Radiation therapy was performed as a salvage treatment, while awaiting liver transplantation or if no other treatment was possible.

RESULTS

One hundred and thirty-six patients were consecutively included in the study. The median follow-up was 13months. Median total dose prescribed, fractionation and overall treatment time were respectively 45Gy, three fractions and 5 days. Overall survival, progression-free survival and local control rates at 1year and 2years were 79.8 % and 63.5 %, 61.3 % and 39.4 %; 94.5 % and 91 %. Two grade 3 acute toxicity events and two grade 4 late toxicity events corresponding to a duodenal ulcer have been reported. Seven patients underwent classic radiation-induced hepatitis and 13 patients showed non-classical radiation-induced hepatitis. Barcelona Clinic Liver Cancer stage, World Health Organisation grade and planning target volume were correlated with overall survival in univariate Cox analysis.

CONCLUSION

Stereotactic body radiation therapy is effective and well-tolerated for inoperable hepatocellular carcinoma or as a bridge to liver transplantation. Toxicity is mainly related to cirrhotic background and requires a selection of patients and strict dose constraints.

Reirradiation of gliomas under stereotactic conditions: Prognostic factors for survival without relapse or side effects, a retrospective study at Tours regional university hospital (France)

PURPOSE

To search for factors correlated with relapse-free survival following stereotactic reirradiation in patients with recurrent glioma following radiochemotherapy and evaluate tolerance to this treatment.

PATIENTS AND METHODS

Initial radiotherapy was given according to the protocol of Stupp and al. Reirradiation was performed using the CyberKnife^® system. Patients could have had surgical resection initially and at the time of recurrence. We analysed 13 patients treated between July 2010 and September 2014. The median age was 55 years. The doses delivered ranged from 20 to 36Gy, in one to ten fractions.

RESULTS

Median survival after stereotactic radiotherapy was 14 months. Survival without relapse was 3.7 months. Factors significantly influencing duration of relapse-free survival were: age (P=0.04), total dose (P=0.02), dose per fraction (P=0.04) and number of fractions (P=0.01). We found no correlation between gross tumour volume, clinical target volume, grade of tumour or prescription isodose and relapse-free survival following radiochemotherapy. Three patients developed radionecrosis.

CONCLUSION

Reirradiation under stereotactic conditions is well tolerated. A dose of more than 30Gy delivered in 5 or more fractions seems to prolong relapse-free survival.

[Doses to organs at risk in conformational and stereotactic body radiation therapy: Liver]

The liver is an essential organ that ensures many vital functions such as metabolism of bilirubin, glucose, lipids, synthesis of coagulation factors, destruction of many toxins, etc. The hepatic parenchyma can be irradiated during the management of digestive tumors, right basithoracic, esophagus, abdomen in toto or TBI. In addition, radiotherapy of the hepatic area, which is mainly stereotactic, now occupies a central place in the management of primary or secondary hepatic tumors. Irradiation of the whole liver, or part of it, may be complicated by radiation-induced hepatitis. It is therefore necessary to respect strict dosimetric constraints both in stereotactic and in conformational irradiation in order to limit the undesired irradiation of the hepatic parenchyma which may vary according to the treatment techniques, the basic hepatic function or the lesion size. The liver is an organ with a parallel architecture, so the average tolerable dose in the whole liver should be considered rather than the maximum tolerable dose at one point. The purpose of this article is to propose a development of dose recommendations during conformation or stereotactic radiotherapy of the liver.