BackgroundIntra-individual heterogeneity of cardiac exposure is an issue in breast cancer (BC) radiotherapy that was poorly considered in previous cardiotoxicity studies mainly based on mean heart dose (MHD). This dosimetric study analyzes the distribution of individually-determined radiation doses to the heart and its substructures including coronary arteries and evaluate whether MHD is a relevant surrogate parameter of dose for these substructures.MethodsData were collected from the BACCARAT prospective study that included left or right unilateral BC patients treated with 3D-Conformal Radiotherapy (RT) between 2015 and 2017 and followed-up for 2 years with repeated cardiac imaging examinations. A coronary computed tomography angiography (CCTA) was performed before RT for all patients. Registration of the planning CT and CCTA images allowed delineation of the coronary arteries on the planning CT images. Using the 3D dose matrix generated during treatment planning and the added coronary contours, dose distributions were generated for whole heart and the following substructures: left ventricle (LV), left main coronary artery (LMCA), left anterior descending artery (LAD), left circumflex artery (LCX) and right coronary artery (RCA). A descriptive analysis of the physical doses in Gray (Gy) was performed, Dmean was the volume-weighted mean dose.ResultsDose distributions were generated for 89 left-sided BC patients (MHD = 2.9 ± 1.5 Gy, Dmean_LAD = 15.7 ± 3.1 Gy) and 15 right-sided BC patients (MHD = 0.5 ± 0.1 Gy; Dmean_RCA = 1.2 ± 0.4 Gy). For left-sided BC patients, the ratio Dmean_LAD/MHD was around 5. Pearson correlation coefficients between MHD and Dmean for delineated substructures were all statistically significant. However, for all substructures, the coefficient of determination R2 indicated that the proportion of the variance in Dmean of the substructure predictable from MHD was moderate to low (in particular R2 = 0.45 for LAD). Among left-sided BC patients with MHD < 3Gy, 56% of patients could nevertheless receive LAD doses above 40Gy (V40 > 0).ConclusionOur study illustrates that MHD is not enough to predict with confidence individual patient dose to the LV and coronary arteries, in particular the LAD. For precise radiotherapy-induced cardiotoxicity studies it would be necessary to consider the distribution of doses within these cardiac substructures rather than just the MHD.Trial registrationClinicalTrials.gov: NCT02605512, Registered 6 November 2015 - Retrospectively registered.
The efficacy and toxicity of the new anthracycline, 4'-0-tetrahydropyranyl doxorubicin (THP) (50 mg/m2 intravenous [IV] bolus) in association with cisplatin (100 mg/m2 IV as a 4-hour infusion) was assessed in 31 patients with advanced ovarian carcinoma. Twenty-eight patients were assessable for toxicity among whom 25 were assessable for response (International Federation of Gynecology and Obstetrics [FIGO] stage IIIa, four patients; IIIb, 15 patients; IV, six patients). Nine patients had received prior treatment. Patients were randomized to receive schedule (sch) A (THP at 6 hours, then cisplatin from 16 to 20 hours) or sch B (THP at 18 hours, then cisplatin from 4 to 8 hours). Sch A was hypothesized as less toxic since THP was best tolerated in the late rest span and cisplatin near the middle of the activity span in experimental studies. The rate of clinical complete response (CR) was 52%, that of partial response (PR) was 12%, and the overall clinical response rate (CR plus PR) was 64% (sch A, 73%; sch B, 57%). Median progression-free survival and survival times were, respectively, 10 and 19 months. Of 12 patients in clinical CR evaluated at second-look laparotomy, four had a pathological CR (33%), and three had microscopic residual disease (MD). The overall rate of pathological CR was 16%. Sch A was associated with less neutropenia (P = .10), thrombocytopenia (P less than .01), anemia (P less than .01), and renal toxicity (P less than .05) than sch B. Of four patients withdrawn for toxicity, three were on sch B (one death). Mean dose intensities (DIs) of THP and cisplatin, respectively, decreased by 30% and 47% over the five initial courses. Such decrease was significantly more pronounced for sch B than for sch A in previously untreated patients (P from 2-way analysis of variance [ANOVA] less than .01). THP-cisplatin is active against advanced ovarian cancer, and its toxicities can be significantly decreased by dosing THP in the early morning and cisplatin in the late afternoon as compared with THP in the evening and cisplatin the next morning.
BackgroundBreast cancer (BC) radiotherapy (RT) can induce cardiotoxicity, with adverse events often observed many years after BC RT. Subclinical left ventricular (LV) dysfunction can be detected early after BC RT with global longitudinal strain (GLS) measurement based on 2D speckle-tracking echocardiography. This 6-month follow-up analysis from the BACCARAT prospective study aimed to investigate the association between cardiac radiation doses and subclinical LV dysfunction based on GLS reduction.MethodsThe patient study group consisted of 79 BC patients (64 left-sided BC, 15 right-sided BC) treated with RT without chemotherapy. Echocardiographic parameters, including GLS, were measured before RT and 6 months post-RT. The association between subclinical LV dysfunction, defined as GLS reduction > 10%, and radiation doses to whole heart and the LV were performed based on logistic regressions. Non-radiation factors associated with subclinical LV dysfunction including age, BMI, hypertension, hypercholesterolemia and endocrine therapy were considered for multivariate analyses.ResultsA mean decrease of 6% in GLS was observed (− 15.1% ± 3.2% at 6 months vs. − 16.1% ± 2.7% before RT, p = 0.01). For left-sided patients, mean heart and LV doses were 3.1 ± 1.3 Gy and 6.7 ± 3.4 Gy respectively. For right-sided patients, mean heart dose was 0.7 ± 0.5 Gy and median LV dose was 0.1 Gy. Associations between GLS reduction > 10% (37 patients) and mean doses to the heart and the LV as well as the V20 were observed in univariate analysis (Odds Ratio = 1.37[1.01–1.86], p = 0.04 for Dmean Heart; OR = 1.14 [1.01–1.28], p = 0.03 for Dmean LV; OR = 1.08 [1.01–1.14], p = 0.02 for LV V20). In multivariate analysis, these associations did not remain significant after adjustment for non-radiation factors. Further exploratory analysis allowed identifying a subgroup of patients (LV V20 > 15%) for whom a significant association with subclinical LV dysfunction was found (adjusted OR = 3.97 [1.01–15.70], p = 0.048).ConclusionsThis analysis indicated that subclinical LV dysfunction defined as a GLS decrease > 10% is associated with cardiac doses, but adjustment for non-radiation factors such as endocrine therapy lead to no longer statistically significant relationships. However, LV dosimetry may be promising to identify high-risk subpopulations. Larger and longer follow-up studies are required to further investigate these associations.Trial registrationClinicalTrials.gov: NCT02605512, Registered 6 November 2015 - Retrospectively registered
This multidisciplinary study summarising published data and current practices produced a therapeutic algorithm, which should facilitate the standardised, optimised management of skin toxicity associated with EGFR inhibitors in France.
BackgroundConsiderable variation in intravenous 5-fluorouracil (5-FU) metabolism can occur due to the wide range of dihydropyrimidine dehydrogenase (DPD) enzyme activity, which can affect both tolerability and efficacy. The oral fluoropyrimidine tegafur-uracil (UFT) is an effective, well-tolerated and convenient alternative to intravenous 5-FU. We undertook this study in patients with locally advanced rectal cancer to evaluate the efficacy and tolerability of UFT with leucovorin (LV) and preoperative radiotherapy and to evaluate the utility and limitations of multicenter staging using pre- and post-chemoradiotherapy ultrasound. We also performed a validated pretherapy assessment of DPD activity and assessed its potential influence on the tolerability of UFT treatment.MethodsThis phase II study assessed preoperative UFT with LV and radiotherapy in 85 patients with locally advanced T3 rectal cancer. Patients with potentially resectable tumors received UFT (300 mg/m/2/day), LV (75 mg/day), and pelvic radiotherapy (1.8 Gy/day, 45 Gy total) 5 days/week for 5 weeks then surgery 4-6 weeks later. The primary endpoints included tumor downstaging and the pathologic complete response (pCR) rate.ResultsMost adverse events were mild to moderate in nature. Preoperative grade 3/4 adverse events included diarrhea (n = 18, 21%) and nausea/vomiting (n = 5, 6%). Two patients heterozygous for dihydropyrimidine dehydrogenase gene (DPYD) experienced early grade 4 neutropenia (variant IVS14+1G > A) and diarrhea (variant 2846A > T). Pretreatment ultrasound TNM staging was compared with postchemoradiotherapy pathology TN staging and a significant shift towards earlier TNM stages was observed (p < 0.001). The overall downstaging rate was 42% for primary tumors and 44% for lymph nodes. The pCR rate was 8%. The sensitivity and specificity of ultrasound for staging was poor. Anal sphincter function was preserved in 55 patients (65%). Overall and recurrence-free survival at 3 years was 86.1% and 66.7%, respectively. Adjuvant chemotherapy was administered to 36 node-positive patients (mean duration 118 days).ConclusionPreoperative chemoradiotherapy using UFT with LV plus radiotherapy was well tolerated and effective and represents a convenient alternative to 5-FU-based chemoradiotherapy for the treatment of resectable rectal cancer. Pretreatment detection of DPD deficiency should be performed to avoid severe adverse events.
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