84 research outputs found
EROS 2.0 study: evaluation of two interventional radiotherapy (brachytherapy) schedules for endometrial cancer: a comparison of late vaginal toxicity rates
Background To compare the late toxicity rates after two different high dose rate (HDR) adjuvant intravaginal interventional radiotherapy (IRT-brachytherapy) dose schedules in stage I-II endometrial cancer. Methods Stage I-II patients with endometrial cancer treated with surgery (with or without lymphadenectomy) and adjuvant HDR-IRT between 2014 and 2020 were included in this analysis. Patients were treated with two schedules. In the first cohort (C1), 21 Gy were delivered in three weekly fractions (7 Gy) prescribed 0.5 cm from the applicator surface. In the second cohort (C2), 24 Gy were delivered in four weekly fractions (6 Gy). The clinical target volume was the upper third of the vagina for C1 and the upper 3 cm for C2. HDR-IRT technique and point prescription (5 mm depth from the applicator surface) were the same for all patients. Vaginal toxicity was scored according to the CTCAE 5.0 scale in terms of the presence versus absence of any toxicity grade. The correlation among toxicity and clinical covariates (age, lymphadenectomy, fractionation, stage) was tested by Pearson correlation test (univariate) and by logistic regression (multivariable). Results 114 stage I and three stage II patients, median age 62 (range: 32-85) years, were included in this analysis. The mean follow-up was 56.3 months in C1 (40-76) and 20 months in C2 (8-42). Vaginal late toxicity was recorded in 40 and 15 patients in C1 and 2, respectively. Age, lymphadenectomy, and fractionation were significantly correlated with toxicity at univariate analysis (p value = 0.029, 0.006, and 0.002, respectively), while stepwise logistic regression confirmed only age and fractionation as significantly correlated parameters (p value = 0.02 and 0.001, respectively). Three-year local relapse-free, distant metastasis-free and cause-specific survival rates were 96.6%, 94.8%, and 99.1%, respectively. Conclusions This analysis showed lower vaginal late toxicity rate in C2 compared to C1
Irinotecan+5-fluorouracil with concomitant pre-operative radiotherapy in locally advanced non-resectable rectal cancer: a phase I/II study
In the UK, 10% of patients diagnosed with rectal cancer have inoperable disease at presentation. This study ascertained whether the resectability rate of inoperable locally advanced rectal cancer was improved by administration of intravenous irinotecan, 5-fluorouracil (5-FU) and pelvic radiotherapy. During phase I of the trial (n=12), the dose of irinotecan was escalated in three-patient cohorts from 50 mg m−2 to 60 mg m−2 to 70 mg m−2 to identify the maximum tolerated dose (60 mg m−2). In phase II, 31 patients with non-resectable disease received 45 Gy radiotherapy and 5-FU infusions (200 mg m−2 per day) for 5 weeks. Irinotecan (60 mg m−2) was given on days 1, 8, 15 and 22. After treatment, patients were operated on if possible. Thirty patients completed the protocol, 28 underwent surgery. Before surgery, MRI restaging of 24 patients showed that 19 (79%) had a reduction in tumour stage after treatment (seven complete clinical response and 12 partial). Of 27 patients followed up after surgery, 22 (81%) had clear circumferential resection margins. Disease-free and overall survival estimates at 3 years were 65 and 90%, respectively. The regimen was well tolerated. Irinotecan, 5-FU and radiotherapy results in tumour downgrading, allowing resection of previously inoperable tumour with acceptable toxicity
The Cyclostratigraphy Intercomparison Project (CIP): consistency, merits and pitfalls
Cyclostratigraphy is an important tool for understanding astronomical climate forcing and reading geological time in sedimentary sequences, provided that an imprint of insolation variations caused by Earth’s orbital eccentricity, obliquity and/or precession is preserved (Milankovitch forcing). Numerous stratigraphic and paleoclimate studies have applied cyclostratigraphy, but the robustness of the methodology and its dependence on the investigator have not been systematically evaluated. We developed the Cyclostratigraphy Intercomparison Project (CIP) to assess the robustness of cyclostratigraphic methods using an experimental design of three artificial cyclostratigraphic case studies with known input parameters. Each case study is designed to address specific challenges that are relevant to cyclostratigraphy. Case 1 represents an offshore research vessel environment, as only a drill-core photo and the approximate position of a late Miocene stage boundary are available for analysis. In Case 2, the Pleistocene proxy record displays clear nonlinear cyclical patterns and the interpretation is complicated by the presence of a hiatus. Case 3 represents a Late Devonian proxy record with a low signal-to-noise ratio with no specific theoretical astronomical solution available for this age. Each case was analyzed by a test group of 17-20 participants, with varying experience levels, methodological preferences and dedicated analysis time. During the CIP 2018 meeting in Brussels, Belgium, the ensuing analyses and discussion demonstrated that most participants did not arrive at a perfect solution, which may be partly explained by the limited amount of time spent on the exercises (∼4.5 hours per case). However, in all three cases, the median solution of all submitted analyses accurately approached the correct result and several participants obtained the exact correct answers. Interestingly, systematically better performances were obtained for cases that represented the data type and stratigraphic age that were closest to the individual participants’ experience. This experiment demonstrates that cyclostratigraphy is a powerful tool for deciphering time in sedimentary successions and, importantly, that it is a trainable skill. Finally, we emphasize the importance of an integrated stratigraphic approach and provide flexible guidelines on what good practices in cyclostratigraphy should include. Our case studies provide valuable insight into current common practices in cyclostratigraphy, their potential merits and pitfalls. Our work does not provide a quantitative measure of reliability and uncertainty of cyclostratigraphy, but rather constitutes a starting point for further discussions on how to move the maturing field of cyclostratigraphy forward
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The Cyclostratigraphy Intercomparison Project (CIP): consistency, merits and pitfalls
Cyclostratigraphy is an important tool for understanding astronomical climate forcing and reading geological time in sedimentary sequences, provided that an imprint of insolation variations caused by Earth’s orbital eccentricity, obliquity and/or precession is preserved (Milankovitch forcing). Numerous stratigraphic and paleoclimate studies have applied cyclostratigraphy, but the robustness of the methodology and its dependence on the investigator have not been systematically evaluated. We developed the Cyclostratigraphy Intercomparison Project (CIP) to assess the robustness of cyclostratigraphic methods using an experimental design of three artificial cyclostratigraphic case studies with known input parameters. Each case study is designed to address specific challenges that are relevant to cyclostratigraphy. Case 1 represents an offshore research vessel environment, as only a drill-core photo and the approximate position of a late Miocene stage boundary are available for analysis. In Case 2, the Pleistocene proxy record displays clear nonlinear cyclical patterns and the interpretation is complicated by the presence of a hiatus. Case 3 represents a Late Devonian proxy record with a low signal-to-noise ratio with no specific theoretical astronomical solution available for this age. Each case was analyzed by a test group of 17-20 participants, with varying experience levels, methodological preferences and dedicated analysis time. During the CIP 2018 meeting in Brussels, Belgium, the ensuing analyses and discussion demonstrated that most participants did not arrive at a perfect solution, which may be partly explained by the limited amount of time spent on the exercises (∼4.5 hours per case). However, in all three cases, the median solution of all submitted analyses accurately approached the correct result and several participants obtained the exact correct answers. Interestingly, systematically better performances were obtained for cases that represented the data type and stratigraphic age that were closest to the individual participants’ experience. This experiment demonstrates that cyclostratigraphy is a powerful tool for deciphering time in sedimentary successions and, importantly, that it is a trainable skill. Finally, we emphasize the importance of an integrated stratigraphic approach and provide flexible guidelines on what good practices in cyclostratigraphy should include. Our case studies provide valuable insight into current common practices in cyclostratigraphy, their potential merits and pitfalls. Our work does not provide a quantitative measure of reliability and uncertainty of cyclostratigraphy, but rather constitutes a starting point for further discussions on how to move the maturing field of cyclostratigraphy forward
A phase I/II study of oxaliplatin when added to 5-fluorouracil and leucovorin and pelvic radiation in locally advanced rectal cancer: a Colorectal Clinical Oncology Group (CCOG) study
The purpose of this study was to evaluate the maximum tolerated dose (MTD) and recommended dose of oxaliplatin given synchronously with 5-fluorouracil (5FU), leucovorin (LV) and preoperative pelvic radiation for primary unresectable, locally advanced, rectal cancer. Preoperative pelvic radiotherapy using a three- or four-field technique and megavoltage photons comprised 45 Gy given in 25 fractions, 1.8 Gy per fraction, and delivered with escalating doses of oxaliplatin in combination with low-dose LV and 5FU. Chemotherapy was given synchronously with radiotherapy in weeks 1 and 5. Escalating doses of oxaliplatin (85, 130 and 150 mg m−2) were given on days 2 and 30, followed by low-dose LV (20 mg m−2) and 5FU (350 mg m−2), both given on days 1–5 and 29–33. Surgery was performed 6–10 weeks later. The MTD was determined as the dose causing more than a third of patients to have a dose-limiting toxicity (DLT). Once the MTD was reached, a further 14 patients were treated at the dose level below the MTD. In all, 32 patients received oxaliplatin at the three dose levels, median age 60 years (range 31–79), 24 males and eight females. The MTD was reached at 150 mg m−2 when four out of six patients experienced DLT. Dose-limiting grade 3 or 4 diarrhoea was reported in two out of six patients at 85 mg m−2, 5 out of 20 at 130 mg m−2 and four out of 6 at 150 mg m−2. Grade 3 neuropathy was reported at 130 mg m−2 (1 out of 20) and at 150 mg m−2 (two out of six), and serious haematological toxicity was minimal; one grade 3 anaemia at 150 mg m−2. In all, 28 out of 32 patients completed all treatments as planned; three had radiotherapy interrupted and three a chemotherapy dose reduction. Four patients did not proceed to surgery due to the presence of metastatic disease (two), unfitness (one) or patient refusal (one). Also, 28 patients underwent surgical resection. Histopathology demonstrated histopathological complete response (pCR) 2 out of 27 (7%), Tmic 3 out of 27 (11%), pCR+Tmic 5 out of 27 (19%), pT0–2 6 out of 27 (22%) and histologically confirmed clear circumferential resection margins in 22 out of 27 (81%). Dose-limiting toxicity with oxaliplatin is 150 mg m−2 given days 2 and 30 when added to the described 5FU LV and 45 Gy radiation preoperatively. The acceptable toxicity and compliance at 130 mg m−2 recommend testing this dose in future phase II studies. The tumour downstaging and complete resection rates are encouragingly high for this very locally advanced group
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