Comparison of passive-beam proton therapy,helical tomotherapy and 3D conformal radiation therapy in Hodgkin's lymphoma female patients receiving involved-field or involved site radiation therapy

PurposeSecond cancers and cardiovascular toxicities are long term radiation toxicity in locally advanced Hodgkin's lymphomas. In this study, we evaluate the potential reduction of dose to normal tissue with helical tomotherapy and proton therapy for Hodgkin's lymphoma involved-field or involved-site irradiation compared to standard 3D conformal radiation therapy.Patients and methodsFourteen female patients with supradiaphragmatic Hodgkin's lymphoma were treated at our institution with 3D conformal radiation therapy or helical tomotherapy to a dose of 30 Gy in 15 fractions. A planning comparison was achieved including proton therapy with anterior/posterior passive scattered beams weighted 20 Gy/10 Gy.ResultsMean doses to breasts, lung tissue and heart with proton therapy were significantly lower compared to helical tomotherapy and to 3D conformal radiation therapy. Helical tomotherapy assured the best protection of lungs from doses above 15 Gy with the V_20 Gy equal to 16.4%, compared to 19.7% for proton therapy (P = 0.01) or 22.4% with 3D conformal radiation therapy (P < 0.01). Volumes of lung receiving doses below 15 Gy were significantly larger for helical tomotherapy than for proton therapy or 3D conformal radiation therapy, with respective lung doses V_10 Gy = 37.2%, 24.6% and 27.4%. Also, in the domain of low doses, the volumes of breast that received more than 10 Gy or more than 4 Gy with helical tomotherapy were double the corresponding volumes for proton therapy, with V_4 Gy representing more than a third of one breast volume with helical tomotherapy.ConclusionsHelical tomotherapy achieved a better protection to the lungs for doses above 15 Gy than passive proton therapy or 3D conformal radiation therapy. However, dose distributions could generally be improved by using protons even with our current passive-beam technology, especially allowing less low dose spreading and better breast tissue sparing, which is an important factor to consider when treating Hodgkin's lymphomas in female patients. Prospective clinical study is needed to evaluate the tolerance and confirm these findings.     

Radiation dose to the low axilla in patients treated for early-stage breast cancer by locoregional intensity-modulated radiotherapy (IMRT)

PurposeTo determine the dose received by the low axilla during locoregional radiotherapy (RT) for early-stage breast cancer and to assess the impact of the treatment technique (three-dimensional conformal radiotherapy (3D-CRT) or rotational IMRT (VMAT) or helical tomotherapy (HT).Materials and methodsThe dosimetric study was performed on patients receiving normofractionated (NFRT - 50 Gy in 25 fractions) or hypofractionated (HFRT - 40 Gy in 15 fractions) locoregional radiotherapy (breast or chest wall and internal mammary, supraclavicular and infraclavicular nodes ± axillary nodes) by 3D-CRT or VMAT or HT at the Institut Curie Paris. Patients treated by breast-conserving surgery received a boost dose of 16 Gy and 10 Gy to the tumour bed, respectively.ResultsSixty-eight patients treated by RT from February 2017 to January 2019 were studied. The mean dose received by the low axilla when it was not part of the target volume was 30.8 Gy, 41.0 Gy and 44.4 Gy by 3D-CRT, VMAT and HT, respectively for NFRT and 24.2 Gy, 33.0 Gy and 34.9 Gy, respectively, for HFRT. With NFRT, 4.1% of the axilla received 95% (V95) of the prescribed dose by 3D-CRT compared to 24.5% and 33.6% by VMAT and HT, respectively; with HFRT, V95 was 3.9%, 19.5% and 24.1%, respectively.ConclusionThe axilla receives a non-negligible dose during locoregional radiotherapy; this dose is greater when VMAT or HT are used. Prospective studies must be conducted to assess the impact of this axillary dose in terms of morbidity, which currently remains unknown.     

Late hepatic toxicity after breast cancer intensity-modulated radiotherapy using helicoidal tomotherapy

PurposeHelical tomotherapy (HT) is a rotational intensity-modulated radiation therapy (IMRT) technique that allows target conformal irradiation and efficient organs at risk (OAR) sparing in the case of complex target volumes and specific anatomic considerations, but increases the “low-dose bath” to non-target volumes. The aim of this study was to analyze the delayed hepatotoxicity after rotational IMRT (HT) radiation therapy for non-metastatic breast cancer.Patients and methodsThis single-center retrospective study included all non-metastatic breast cancer patients with a normal pre-radiotherapy biological hepatic function who were treated with tomotherapy between January 2010 and January 2021 and for whom the dosimetric parameters for the whole liver were assessable. A logistic regression analysis was employed. The selected covariates for the multivariate analysis were those with a P-value that was less or equal to 0.20 in the univariate analysis.ResultsForty-nine patients were included in this study: 11 patients (22%) received Trastuzumab for 1 year in tumors with an HER2-expression; 27 patients (55%) received radiation therapy for cancer of the right or bilateral breasts; 43 patients (88%) received lymph node irradiation and 41 patients (84%) received a tumor bed boost. Mean and maximum doses to the liver were 2.8 Gy [0.3–16.6] and 26.9 Gy [0.7–51.7], respectively. With a median follow-up after irradiation was 5.4 years (range, 6 to 115 months), 11 patients (22%) had developed delayed low grade biological hepatic abnormalities: all patients had grade 1 delayed hepatotoxicity; 3 patients (6%) had additional grade 2 delayed hepatotoxicity. There was no hepatotoxicity at grade 3 or higher. According to the univariate and multivariate analysis, Trastuzumab was a significant predictive variable of late biological hepatotoxicity (OR = 4.4 [1.01–20.18], P = 0.04). No other variable was statistically associated with delayed biological hepatotoxicity.ConclusionDelayed hepatotoxicity after multimodal non-metastatic breast cancer management including rotational IMRT was negligible. Consequently, the liver doesn’t have to be considered like an organ-at-risk in the analysis of breast cancer radiotherapy but future prospectives studies are needed to confirm these findings.     

Tolerance and efficacy of dose escalation using IMRT combined with chemotherapy for unresectable esophageal carcinoma: Long-term results of 51 patients

PurposeThe optimal dose in esophageal cancer patients treated with definitive chemoradiation (CRT) remains debated. We herein report on the dosimetric results, treatment-related toxicities and long-term outcomes of escalated dose up to 60 Gy delivered with intensity-modulated radiotherapy (IMRT).Materials and methodsAll consecutive patients that received a definitive CRT > 50 Gy for an unresectable esophageal carcinoma between 2010 and 2015 were retrospectively evaluated for this study. Methodology included data base search, delayed toxicity grading, statistical testing including frequency analysis and survival analysis.ResultsA total of 51 patients were irradiated for a squamous cell carcinoma (86.3%) or an adenocarcinoma (13.7%). The median age at diagnosis was 62 years. Seven patients were simultaneously irradiated for another synchronous primary tumor. Forty-six patients (90.2%) received concurrent platin-based chemotherapy. The median prescribed doses were 60 Gy (54–66) and 48 Gy (44.8–56) delivered in 30 (27–35) fractions to the high and the low risks PTV respectively. The mean dose delivered to the lungs was 11.4 Gy (IC 95%: 4.8–19.8), the median volumes receiving up to 20 Gy (V20) and 30 Gy (V30) were 13.5% (3.0–46.0) and 4.6% (0.7–19.8) respectively. The mean dose delivered to the heart was 13.9 Gy (IC 95%:0.3–31.3) with a median V40 of 3.3% (0.0–25.0). One treatment-related death occurred within days after RT completion (neutropenic aplasia). After a median follow-up of 2.7 years (95% CI: 1.9–4.3), the 2-year overall survival, disease free survival and loco-regional control rates were 53.6%, 42.0% and 72.8% respectively. Delayed treatment related-toxicities ≤ grade 3 occurred among 25 patients (62.5%) mostly esophageal stricture (79.2%).ConclusionWe demonstrated in this study that dose escalation using IMRT in combination with platin-based chemotherapy as a definitive treatment for esophageal carcinoma is safe and results in higher loco-regional and control survival when compared to previously reported data.     

Five-fraction HDR brachytherapy in locally advanced cervical cancer: A monocentric experience

PurposeThe 5-fraction scheme (5 × 5–5.5 Gy) is a common High-Dose Rate (HDR) intracavitary brachytherapy regimen for locally advanced cervical cancer (LACC). Yet, its equivalence with Pulse-Dose rate (PDR) schemes remains unproved. The present study aimed at reporting on the outcome of LACC patients treated with 5-fraction HDR brachytherapy.Materials and methodsThe medical records of all consecutive patients treated with curative-intent HDR brachytherapy for a LACC in a French Cancer Center were retrospectively reviewed.ResultsThirty-eight LACC patients underwent a 5-fraction intracavitary HDR brachytherapy between 2015 and 2019 (median dose = 25 Gy/5 fractions, following external-beam radiotherapy). Median age at diagnosis was 60 (range: 29–87). Thirty-one patients (81.5%) underwent concurrent chemotherapy. Tumor stages ranged from 3 IB2 (7.8%), 4 IB3 (10.5%), 4 IIA2 (10.5%), 12 IIB (31.7%), 1 IIIA (2.6%), 2 IIIB (5.3%), 7 IIIC1 (18.5%), 4 IIIC2 (10.5%), 1 IVA (2.6%) (2018 FIGO). Median D90% to CTV_HR reached 79.5 Gy (EQD2). Median D90% to CTV_IR reached 59.5 Gy (EQD2). Median Bladder D2cc was 69.8 Gy (EQD2). Median Rectum D2cc was 58.3 Gy (EQD2). Acute/late grade 3 toxicity was reported in one patient (2.6%). No grade 4–5 toxicity occurred. At a median 38 months follow-up, 10 patients (26.3%) had local (n = 7, 18.4%), nodal (n = 6, 15.7%) and/or distant (n = 7, 18.4%) relapse. Three-year overall survival rate was of 81.6%.ConclusionThe 5-fraction HDR scheme was well tolerated even in frail patients. Three-year local control was lower than expected. Treatment (absence of parametrial interstitial implants and use of cervical EBRT boost) and patients’ characteristics (age, comorbidities) may explain such results.     

Stereotactic body radiotherapy for mediastinal lymph node with CyberKnife®: Efficacy and toxicity

PuprposeStereotactic body radiotherapy is more and more used for treatment of oligometastatic mediastinal lymph nodes. The objective of this single-centre study was to evaluate its efficacy in patients with either a locoregional recurrence of a pulmonary or oesophageal cancer or with distant metastases of extrathoracic tumours.Patients and methodsPatients with oligometastatic mediastinal lymph nodes treated with CyberKnife from June 2010 to September 2020 were screened. The primary endpoint was to assess local progression free survival and induced toxicity. Secondary endpoints were overall survival and progression free survival. The delay before introduction of systemic treatment in the subgroup of patients who did not receive systemic therapy for previous progression was also evaluated.ResultsFifty patients were included: 15 with a locoregional progression of a thoracic primary tumour (87% pulmonary) and 35 with mediastinal metastasis of especially renal tumour (29%). Median follow-up was 27 months (6–110 months). Local progression free survival at 6, 12 and 18 months was respectively 94, 88 and 72%. The rate of local progression was significantly lower in patients who received 36 Gy in six fractions (66% of the cohort) versus other treatment schemes. Two grade 1 acute oesophagitis and one late grade 2 pulmonary fibrosis were described. Overall survival at 12, 18 and 24 months was respectively 94, 85 and 82%. Median progression free survival was 13 months. Twenty-one patients were treated by stereotactic body irradiation alone without previous history of systemic treatment. Among this subgroup, 11 patients (52%) received a systemic treatment following stereotactic body radiotherapy with a median introduction time of 17 months (5–52 months) and 24% did not progress.ConclusionStereotactic body irradiation as treatment of oligometastatic mediastinal lymph nodes is a well-tolerated targeted irradiation that leads to a high control rate and delay the introduction of systemic therapy in selected patients.     

Tomothérapie hélicoïdale dans le traitement du mésothéliome pleural malin : impact des faibles doses sur la toxicité pulmonaire et œsophagienne

PurposeTo evaluate the adjuvant treatment of malignant pleural mesothelioma by helical tomotherapy and the impact of low doses on esophageal and pulmonary toxicity.Patients and methodsBetween June 2007 and May 2011, 29 patients diagnosed with malignant pleural mesothelioma received adjuvant radiotherapy by helical tomotherapy. The median age was 63 years (34–72). Histologically, 83 % of patients had epithelioid malignant pleural mesothelioma. Clinically, 45 % of patients were T3 and 55 % N0. Eighty six percent of the patients were treated by extrapleural pneumonectomy and 35 % received neoadjuvant chemotherapy with platinum and pemetrexed. The median dose in the pneumonectomy cavity was 50 Gy at 2 Gy/fraction.ResultsThe mean follow-up was 2.3 years after diagnosis. Overall survival at 1 and 2 years was 65 and 36 % respectively. The median survival from diagnosis was 18 months. Median lung volumes receiving 2, 5, 10, 13, 15 and 20 Gy (V2, V5, V10, V13, V15 and V20) were 100, 98, 52, 36, 19 and 5 %. The median of the mean remaining lung dose was 11 Gy. Two patients died of pulmonary complications, three patients had grade 3 lung toxicity, while esophageal grade 3–4 toxicity was observed in three other patients. No significant impact of clinical characteristics and dosimetric parameters were found on pulmonary toxicity, however a V10 ≥ 50 %, a V15 ≥ 15 % and mean lung dose of 10 Gy or more had a tendency to be predictive of pulmonary toxicity (P < 0.1). Moreover, in our analysis, the mean lung dose seems to have a significant impact on esophageal toxicity (P = 0.03) as well as low doses to the controlateral lung: V5, V10 and V13 (P < 0.05).ConclusionHelical tomotherapy is a promising technique in the multimodality treatment of malignant pleural mesothelioma. Low doses received by the contralateral lung appear to be the limiting factor. A dosimetric comparison with volumetric modulated arctherapy techniques would be interesting in this setting.     

Stereotactic radiotherapy for large solitary brain metastases

PurposeTo assess effectiveness and toxicity levels of stereotactic radiation therapy without whole brain radiation therapy in patients with solitary brain metastases larger than 3 cm.Patients and methodsBetween June 2007 and March 2009, 12 patients received fractionated stereotactic radiation therapy and 24 patients underwent stereotactic radiosurgery. For the fractionated stereotactic radiation therapy group, 3 × 7.7 Gy were delivered to the planning target volume (PTV); median volume and diameter were 29.4 cm³ and 4.4 cm, respectively. For the stereotactic radiosurgery group, 14 Gy were delivered to the PTV; median volume and diameter were 15.6 cm³ and 3.7 cm, respectively.ResultsMedian follow-up was 218 days. For the fractionated stereotactic radiation therapy group, local control rates were 100% at 360 days and 64% at 720 days; for the stereotactic radiosurgery group, rates were 58% at 360 days and 48% at 720 days (P = 0.06). Median survival time was 504 days for the fractionated stereotactic radiation therapy group and 164 days for the stereotactic radiosurgery group (P = 0.049). Two cases of grade 2 toxicity were observed in the fractionated stereotactic radiation therapy group, and 6 cases of grade 1–2 toxicity, in the stereotactic radiosurgery group.ConclusionsThis study provides data to support that fractionated stereotactic radiation therapy without whole brain radiation therapy with a margin dose of 3 fractions of 7.7 Gy for treatment of solitary large brain metastases is efficient and well-tolerated. Because of the significant improvement in overall survival, this schedule should be assessed in a randomized trial.     

Long duration of immunotherapy before radiosurgery might improve intracranial control of melanoma brain metastases

PurposeDespite significant advances that have been made in management of metastatic melanoma with immune checkpoint therapy, optimal timing of combination immune checkpoint therapy and stereotactic radiosurgery is unknown. We have reported toxicity and efficiency outcomes of patients treated with concurrent immune checkpoint therapy and stereotactic radiosurgery.Patients and methodsFrom January 2014 to December 2016, we analyzed 62 consecutive patients presenting 296 melanoma brain metastases, treated with gamma-knife and receiving concurrent immune checkpoint therapy with anti-CTLA4 or anti-PD1 within the 12 weeks of SRS procedure. Median follow-up time was 18 months (mo) (13–22). Minimal median dose delivered was 18 gray (Gy), with a median volume per lesion of 0.219 cm³.ResultsThe 1-year control rate per irradiated lesion was 89% (CI 95%: 80.41–98.97). Twenty-seven patients (43.5%) developed distant brain metastases after a median time of 7.6 months (CI 95% 1.8–13.3) after gamma-knife. In multivariate analysis, positive predictive factors for intracranial tumor control were: delay since the initiation of immunotherapy exceeding 2 months before gamma-knife procedure (P = 0.003) and use of anti-PD1 (P = 0.006). Median overall survival (OS) was 14 months (CI 95%: 11–NR). Total irradiated tumor volume < 2.1 cm³ was a positive predictive factor for overall survival (P = 0.003). Ten patients (16.13%) had adverse events following irradiation, with four grade ≥ 3. Predictive factors of all grade toxicity were: female gender (P = 0.001) and previous treatment with MAPK (P = 0.05).ConclusionA long duration of immune checkpoint therapy before stereotactic radiosurgery might improve intracranial tumor control, but this relationship and its ideal timing need to be assessed in prospective trials.     

Fractionated Stereotactic Radiation Therapy for Pituitary Adenomas: An alternative escalating protocol of hypofractionated stereotactic radiotherapy delivering 35 Gy in 5 fractions

PurposeEvaluate efficacy and toxicity of hypofractionated stereotactic radiotherapy (HSRT) for patients treated for pituitary adenoma (PA) with an alternative HSRT escalating protocol delivering 35 Gy in 5 fractions.Material and methodsFrom June 2007 to March 2017, 29 patients with pituitary adenoma were treated in Antoine Lacassagne Cancer Centre with an alternative HSRT protocol. Prescribed dose was 35 Gy in 5 fractions of 7 Gy. Radiographic responses were assessed by annual MRI. Hormone blood samples were evaluated each year after HSRT.ResultsA total of 29 patients aged between 23 and 86 years (median 54 years) were included. Twelve patients received HSRT for recurrent cases and 12 received postoperative adjuvant HSRT, 5 patients did not have surgery. After a median follow-up period of 47 months local control rate was 96%. One patient presented an out-field tumor regrowth 73 months after HSRT. The majority of PA were endocrine-active (18 patients, 62%). After HSRT, 8 patients (44%) presented complete response on initial secretion, 4 patients (23%) presented partial response on initial secretion. Four patients (14%) presented grade 2 or more acute radiation toxicities. One grade 4 visual disorder was observed for one patient.ConclusionsHSRT delivering 35 Gy in 5 fractions represents a feasible treatment and shows promising results to reduce hormonal overproduction and to improve local control in PA.     

Patterns of locoregional failure in women with early-stage breast cancer treated by whole breast irradiation in the lateral isocentric decubitus position: Large-scale single-centre experience

PurposeThe purpose of this study was to evaluate locoregional control and describe the patterns of failure in patients with breast cancer receiving whole breast radiotherapy in the isocentric lateral decubitus position technique.Patients and methodsIn a series of 832 consecutive female patients with early-stage breast cancer including invasive and in situ tumours treated by breast-conserving surgery followed by three-dimensional conformal whole breast irradiation in the isocentric lateral decubitus position between 2005 and 2010, all patients who experienced locoregional recurrence were studied. Five-year recurrence-free and overall survival rates were calculated. Regional recurrence mapping patterns were also determined.ResultsThe median age of this series of 832 women was 61.5 years (range: 29–90 years). Various types of fractionation were used: 50 Gy in 25 fractions (17.9%), 66 Gy in 33 fractions (50 Gy in 25 fractions to breast followed by sequential boost to tumour bed to a total dose 66 Gy in 33 fractions.) (46.5%), 40 Gy in 15 fractions or 41.6 Gy in 13 fractions (26.1%) and 30 Gy in 5 fractions (9.5%). With a median follow-up of 6.4 years, only 36 patients experienced locoregional recurrence and no association with the fractionation regimen was identified (P = 0.2). In this population of 36 patients, 28 (3.3%) had “in-breast” local recurrences (77.8%), two had local recurrences and regional lymph node recurrence (5.6%), and six had regional lymph node recurrence only (in non-irradiated areas; 16.6%). The median time to recurrence was 50 months. Complete mapping of patterns of recurrences was performed and, in most cases, local recurrences were situated adjacent to the primary tumour bed. Cases of local recurrences presented a significantly lower distant metastasis rate (P < 0.001) and had a significantly longer overall survival compared to patients with regional lymph node recurrence (P < 0.001). However, multivariate Cox regression analysis showed that the site of recurrence had no significant impact on overall survival (P = 0.14).ConclusionThe results of this study indicate a low local recurrence rate. Further careful follow-up and recording of recurrences is needed to improve the understanding of patterns of recurrence.     

Impact of radiotherapy on survival in resected or unresectable anaplastic thyroid carcinomas,a Rare Cancer Network study

PurposeAnaplastic thyroid carcinomas (ATC) are a heterogenous group of tumors of overall dismal prognosis. We designed models to identify relevant prognostic factors of survival of irradiated ATC patients including radiotherapy modalities (field size, dose).Material and methodsBetween 2000 and 2017, 166 ATC patients’ treatments were divided into surgery and postoperative radiotherapy (poRT) or definitive radiotherapy (RT). Multiple imputation approach was used for missing data. Prognostic factors were identified using Lasso-penalized Cox modelling and predicted risk scores were built.ResultsPatients undergoing RT (n = 70) had more adverse patient and disease characteristics than those undergoing poRT (n = 96). Corresponding median survival rates were 5.4 and 12.1 months, respectively. PoRT patients undergoing poRT more likely received extended-field radiotherapy with prophylactic nodal irradiation, but rather received platinum- vs. adriamycin-based chemoradiotherapy. Radiotherapy was conventionally fractionated, delivered > 60 Gy in 51.9% and 61.7% and used extended fields in 88.5% and 71.2% of patients with poRT or RT. Radiotherapy interruption rates for toxicity were similar in the two groups. The best poRT-group model identified age > 45yo, PS ≥ 1, pathologic tumor stage ≥ pT4b, > N1 and R2 resection as poor prognostic factors. The best RT-group model (C-index of 0.72) identified PS ≥ 3, > N1 and extended-field radiotherapy with prophylactic nodal irradiation (as opposed to tumour-bed irradiation only) as poor prognostic factors.ConclusionIn patients undergoing poRT, radiotherapy parameters had little influence over their survival irrespective of patient, disease characteristics, and quality of resection. In patients undergoing RT, extended-field radiotherapy improved survival in addition to PS and nodal stage.     

Dose distribution of the brain tissue associated with cognitive functions in high-grade glioma patients

PurposeThe purpose of this prospective dosimetric study was to assess the dose distribution regarding the brain areas implied in cognitive functions using two approaches: volumetric modulated arc therapy (VMAT) and helical tomotherapy (HT).Patients and methodsThirty-seven patients were treated using a dual-arc VMAT approach for supratentorial glioblastoma between 2016 and 2018. The total dose of 60 Gy in 30 daily fractions was administered to the planning target volume (PTV). The brain structures that play an important role in cognitive physiology, such as the hippocampi, corpus callosum, cerebellum, subventricular zones (SVZ), were delineated. For each patient, a new treatment plan in HT was determined by a second medical physicist in a blindly fashion according to the same dose constraints and priorities. Statistical analyses were performed using the Wilcoxon-signed rank test.ResultsConformity indexes remained similar with both techniques. The mean values were 0.96 (0.19–1.00) for VMAT and 0.98 (range, 0.84–1.00) for HT, respectively (P = 0.73). Significant D_50% reductions were observed with VMAT compared to HT: 14.6 Gy (3.8–28.0) versus 17.4 Gy (12.1–25.0) for the normal brain (P = 0.014); 32.5 Gy (10.3–60.0) versus 35.6 Gy (17.1–58.0) for the corpus callosum (P = 0.038); 8.1 Gy (0.4–34.0) versus 12.8 Gy (0.8–27.0) for the cerebellum (P < 0.001), respectively.ConclusionThe VMAT approach seemed to improve the sparing of the key brain areas implied in cognitive functions without jeopardizing PTV coverage.     

Dosimetric comparison of four high performance techniques for irradiation of breast cancer patients

PurposeThe use of IMRT for the treatment of breast cancer has been growing considerably in our institution since 2009. Alternatively, helical tomotherapy (HT) using a field width of 2.5 and 5 cm (HT_FW_5), volumetric-modulated arc therapy (VMAT), or proton therapy with pencil-beam scanning (PT-PBS) have also been used to reduce treatment duration or optimize organ-at-risk (OAR) sparing. The purpose of this study was to compare the 4 treatment modalities available at our site.Patients and methodsWe studied 10 patients treated for breast cancer with lymph node involvement. The prescribed dose was 51.8 Gy to the breast with a simultaneous integrated boost up to 63 Gy, and 50.4 Gy to lymph nodes in 28 fractions. The CTV was delineated according to ESTRO Guidelines. Dosimetric planning in routine clinical practice was performed using HT_FW_2.5. The approved clinical plan was compared to the 3 other plans. Dosimetric goals for PTV coverage were D95% ≥ 95% and D2% ≤ 107% of the prescribed dose. Mean and maximum doses to OAR were recorded.ResultsHT_FW_5 and VMAT plans ensure equivalent or even better PTV coverage compared to the initial clinically approved plan but at the cost of poorer OAR sparing. PT_PBS plans showed that an excellent PTV coverage can be maintained with significantly lower doses to OAR.ConclusionHT_FW_5 and VMAT plans allow a significant reduction of treatment duration and can be a good alternative to HT_FW_2.5 for specific populations. HT_FW_2.5 could be chosen for patients at higher risk of side effects. In addition, PT_PBS should be considered in the near future as it has been shown to have a major potential benefit to lower the risk of side effects with the same level of PTV coverage.     

Evaluation of adjuvant vaginal vault brachytherapy in early stage cervical cancer patients

PurposeAdjuvant external beam radiotherapy (EBRT) was shown to decrease pelvic relapses in patients with an early stage cervical cancer and intermediate-risk histopathological prognostic factors, at the cost of increased bowel morbidity. We examined the feasibility and results of adjuvant brachytherapy alone as an alternative to EBRT in this situation.Patients and methodsMedical records of consecutive patients receiving adjuvant brachytherapy between 1991 and 2018 for an early stage cervical cancer were examined. Patients were included if they presented a pT1a2N0 or pT1b1N0 disease following radical colpohysterectomy. Adjuvant vaginal wall brachytherapy (without EBRT) was indicated because of a tumor size ≥ 2 cm and/or presence of lymphovascular space invasion (LVSI). Patients received 60 Gy to 5 mm of the vaginal wall, through low-dose or pulse-dose rate technique. Patients’ outcome was examined for disease control, toxicities and prognostic factors.ResultsA total of 40 patients were included. Eight patients (20%) had LVSI, 26 patients (65%) had a tumor size ≥ 2 cm. With median follow-up time of 42.0 months, 90% of patients were in complete remission and four patients (10%) experienced tumor relapse, all in the peritoneal cavity, and associated with synchronous pelvic lymph node failure in 2/4 patients. No vaginal or isolated pelvic nodal failure was reported. At 5 year, overall survival was 83.6% (CI95%: 67.8–100%) and disease-free survival was 85.1% (CI95%: 72.6–99.9%). In univariate analysis, probability of relapse correlated with tumor size ≥ 3 cm (P = 0.004). No acute or late toxicity grade more than 2 was reported.ConclusionBrachytherapy alone was a well-tolerated adjuvant treatment for selected patients with intermediate risk factors. The risk of relapse in patients with tumor size ≥ 3 cm was however high, suggesting that EBRT is more appropriate in this situation.     

Comparison of dosimetric parameters and acute toxicity of intensity-modulated and three-dimensional radiotherapy in patients with cervix carcinoma: A randomized prospective study

PurposeThe use of intensity-modulated radiotherapy (IMRT) to treat cervix carcinoma has increased, however prospective randomized trials are still lacking.AimTo compare the dosimetric parameters and associated acute toxicity in patients with cervix carcinoma treated with three-dimensional (3D) conformal radiotherapy and IMRT.Patients and methodsForty patients were randomized in two arms each consisting of 20 patients. Patients in both arms received concurrent chemoradiation (cisplatin 40 mg/m² weekly; 50 Gy/25 fractions). Patients were treated with 3D conformal radiotherapy in one arm and with IMRT in another arm. After external beam radiotherapy, all patients received brachytherapy (21 Gy/3 fractions at weekly interval). For dosimetric comparison, both kinds of the plans were done for all the patients. All patients were assessed throughout and until 90 days after completion of treatment for acute gastrointestinal, genitourinary and hematologic toxicities.ResultsBoth plans achieved adequate planning target volume coverage, while mean conformity index was found significantly better in IMRT plans (P-value = 0.001). D₃₅ (dose to 35% volume) and D₅₀ for bladder was reduced by 14.62 and 32.57% and for rectum by 23.82 and 43.68% in IMRT. For IMRT, V₄₅ (volume receiving 45 Gy) of bowel were found significantly lesser (P-value = 0.0001), non-tumour integral dose was found significantly higher (P-value = 0.0240) and V₂₀ of bone marrow was found significantly reduced (P-value = 0.019) in comparison to that in 3D conformal radiotherapy. Significant reduction of grade 2 or more (20 vs 45%; P-value = 0.058) and grade ≥ 3 (5 vs 15%, P-value = 0.004) acute genitourinary toxicity and grade 2 or more (20 vs 45%, P-value = 0.003) and grade 3 or more (5 vs. 20%, P-value = 0.004) acute gastrointestinal toxicity while no significant difference for grade 2 and 3 or more haematological toxicity was noted in patients treated with IMRT compared to 3D conformal radiotherapy.ConclusionIMRT provide a good alternative for treatment of cervix carcinoma with lower acute gastrointestinal and acute genitourinary toxicity with similar target coverage compared to 3D conformal radiotherapy.     

Bénéfice attendu du curage ganglionnaire et de l’exérèse des vésicules séminales pour diminuer la toxicité de la radiothérapie des tumeurs prostatiques de haut risque

PurposeIn case of pelvic lymph node and seminal vesicle dissection followed by prostate cancer intensity-modulated radiotherapy, the objective of the study was to evaluate the dosimetric benefit of reducing the target volume.Patients and methodsA total of 25 patients with high-risk prostate cancer had surgery first followed by intensity-modulated radiotherapy and androgen deprivation. Four treatment planning were simulated for each patient, based on two CT scans performed before and after surgery. The target volumes were: prostate–seminal vesicles–lymph nodes, prostate–lymph nodes, prostate–seminal vesicles and prostate only. The total dose was 46 Gy in the seminal vesicles and lymph nodes, and 80 Gy in the prostate.ResultsCompared to prostate target volume only, the addition of seminal vesicles and lymph nodes multiplied by a factor of 1.6 and 6.5 the target volume, respectively. Decreasing the target volume from prostate–seminal vesicles–lymph nodes to prostate–seminal vesicles, to prostate only decreased the rectal wall mean dose from 49 Gy to 42 Gy, to 36 Gy, and the risk of late rectal bleeding from 4.4% to 3.2%, to 2.4% (P < 0.05), respectively. The bladder wall mean dose decreased from 51 Gy to 40 Gy, to 35 Gy (P < 0,05), respectively. Not irradiating the lymph nodes decreased the absolute risk of diarrhea by 11%.ConclusionLymph node and seminal vesicle dissection before prostate cancer intensity-modulated radiotherapy allows decreasing moderately the risk of digestive toxicity.     

Survival comparision of three-dimensional radiotherapy alone with concurrent chemoradiotherapy for non-surgical esophageal carcinoma

PurposeRadiotherapy is the main treatment method for patients with locally advanced, unresectable esophageal cancer. The aim of this study is to compare overall survival (OS) using 3D radiotherapy (3DRT) alone with concurrent chemoradiotherapy (CCRT) in 296 non-surgical esophageal carcinoma patients.Patents and methodsOver 10 years, of the 480 patients with esophageal carcinoma treated with 3DRT with or without chemotherapy, 148 patients each comprised 3DRT and CCRT groups after propensity score matching.ResultsThe 5- and 10-year OS (P = 0.337) and PFS (P = 0.715) rates for 3DRT alone were 22.0%, 14.4% and 26.1%, 23.2%, respectively, compared with 28.8%, 18.6% and 34.7%, 29.1% for CCRT, respectively. CCRT did not improve 5-year and 10-year OS or PFS in 60–70 Gy group (OS: 27.5% and 25.2%; 17.9% and 17.0%, P = 0.938; PFS: 38.3% and 31.8%; 31.9% and 27.8%, P = 0.890) nor reduce 10-year hematogenous metastasis (31.7% and 28.3%, P = 0.698). CCRT improved 5-year OS and PFS of 50.0–59.9 Gy group (OS: 33.3% and 12.0%, P = 0.029; PFS: 33.1% and 10.6%, P = 0.081). For 3DRT, the 5-year OS and PFS rates were significantly better in the 60–70 Gy group (P = 0.017) compared with 50.0–59.9 Gy group (P = 0.002). For CCRT group, 5-year OS and PFS favored the 50.0–59.9 Gy group, but the difference was insignificant. Major toxicities were greater with CCRT compared with 3DRT.ConclusionFor non-surgical esophageal carcinoma patients, 3DRT combined with CCRT was effective in prolonging both OS and PFS.