13 research outputs found
The Quest for Evidence for Proton Therapy: Model-Based Approach and Precision Medicine
Purpose: Reducing dose to normal tissues is the advantage of protons versus photons. We aimed to describe a method for translating this reduction into a clinically relevant benefit. Methods and Materials: Dutch scientific and health care governance bodies have recently issued landmark reports regarding generation of relevant evidence for new technologies in health care including proton therapy. An approach based on normal tissue complication probability (NTCP) models has been adopted to select patients who are most likely to experience fewer (serious) adverse events achievable by state-of-the-art proton treatment. Results: By analogy with biologically targeted therapies, the technology needs to be tested in enriched cohorts of patients exhibiting the decisive predictive marker: difference in normal tissue dosimetric signatures between proton and photon treatment plans. Expected clinical benefit is then estimated by virtue of multifactorial NTCP models. In this sense, high-tech radiation therapy falls under precision medicine. As a consequence, randomizing nonenriched populations between photons and protons is predictably inefficient and likely to produce confusing results. Conclusions: Validating NTCP models in appropriately composed cohorts treated with protons should be the primary research agenda leading to urgently needed evidence for proton therapy. (C) 2016 Elsevier Inc. All rights reserved
Predictive factors in locally advanced rectal cancer treated with preoperative hyperfractionated and accelerated radiotherapy.
This study examines the prognostic significance of pathologic
factors in patients with primary locally advanced rectal cancer treated
prospectively with preoperative radiotherapy. From 1992 to 1998, 104
patients with rectal cancer of grades T3 or T4 and any N underwent
preoperative radiotherapy followed by surgical resection. Survival
curves were estimated according to the Kaplan-Meier method. Correlation
of outcome with clinicopathologic variables (pathologic tumor
and lymph node staging, histology, radial resection margin
[RRM], clearance, vessel involvement, and tumor regression grade
[TRG], quantitated in 5 grades) was evaluated using the Cox proportional
hazards model. None of the patients achieved a histologically
confirmed complete pathologic response, but 79% of the patients
showed partial tumor regression (TRG2–4) and 21% did not show
any tumor regression (TRG5). Among the tumors, 22% were of a
mucinous type. The RRM was free of tumor in 76% of the surgical
specimens. The median clearance was 2 mm. Vascular invasion was
present in 37 cases (36%). In the univariate analysis, lymph node
metastases, absence of tumor regression, positive RRM, and vascular
invasion were correlated with adverse overall survival and diseasefree
survival; absence of tumor regression, positive RRM, and clearance
<2 mm were correlated with local recurrences; and advanced
pT stage was correlated only with disease-free survival. However, in
the multivariate analysis, only lymph node metastases and RRM were
independent prognostic factors for overall survival and disease-free
survival, and clearance <2 mm was an independent prognostic factor
for local control. Pathologic parameters remain strong determinants
of local recurrence and survival in locally advanced rectal cancer,
treated preoperatively with hyperfractionated and accelerated radiotherapy.
We show that patients with advanced pT, positive lymph
nodes, vascular invasion, positive RRM, clearance <2 mm, or absence
of tumor regression are known to have poor clinical outcome.
HUM PATHOL 34:541-548. © 2003 Elsevier Inc. All rights reserved.
Abbreviations: , computed tomography; DFS, disease-free survival;
HART, hyperfractionated accelerated radiotherapy; OS, overall
survival; RRM, radial resection margin; TRG, tumor regression
grade
Effect of acute aerobic exercise before immunotherapy and chemotherapy infusion in patients with metastatic non-small-cell lung cancer: protocol for the ERICA feasibility trial
International audienceIntroduction Patients with metastatic non-small cell lung cancer (mNSCLC) suffer from numerous symptoms linked to disease and treatment which may further impair the patient’s overall condition. In addition to its benefits on quality of life and fatigue, physical exercise may improve treatment response, notably due to its known effects on the immune system. The ERICA study is designed to assess the feasibility of a supervised acute physical exercise therapy realised immediately prior immune-chemotherapy infusion in patients with mNSCLC. Secondary objectives will examine the effects of acute exercise combined with an unsupervised home-walking programme on clinical, physical, psychosocial and biological parameters. Methods and analysis ERICA is a prospective, monocentric, randomised controlled, open-label feasibility study conducted at the Centre Léon Bérard Comprehensive Cancer Center (France). Thirty patients newly diagnosed with mNSCLC will be randomised (2:1 ratio) to the ‘exercise’ or the ‘control’ group. At baseline and during the last treatment cycle, participants in both groups will receive Physical Activity recommendations, and two nutritional assessments. In the exercise group, participants will receive a 3-month programme consisting of a supervised acute physical exercise session prior to immune-chemotherapy infusion, and an unsupervised home-based walking programme with an activity tracker. The acute exercise consists of 35 min interval training at submaximal intensity scheduled to terminate 15 min prior to infusion. Clinical, physical, biological and psychosocial parameters will be assessed at baseline, 3 and 6 months after inclusion. Biological measures will include immune, inflammatory, metabolic, oxidative stress biomarkers and molecular profiling. Ethics and dissemination The study protocol was approved by the French ethics committee (Comité de protection des personnes Ile de France II, N°ID-RCB 20.09.04.65226, 8 December 2020). The study is registered on ClinicalTrials.gov (NCT number: NCT04676009 ) and is at the pre-results stage. All participants will sign an informed consent form. The findings will be disseminated in peer-reviewed journals and academic conferences
International consensus guidelines on Clinical Target Volume delineation in rectal cancer
Introduction The delineation of Clinical Target Volume (CTV) is a critical step in radiotherapy. Several guidelines suggest different subvolumes and anatomical boundaries in rectal cancer (RC), potentially leading to a misunderstanding in the CTV definition. International consensus guidelines (CG) are needed to improve uniformity in RC CTV delineation. Material and methods The 7 radiation oncologist experts defined a roadmap to produce RC CG. Step 1: revision of the published guidelines. Step 2: selection of RC cases with different clinical stages. Step 3: delineation of cases using Falcon following previously published guidelines. Step 4: meeting in person to discuss the initial delineation outcome, followed by a CTV proposal based on revised and if needed, adapted anatomical boundaries. Step 5: peer review of the agreed consensus. Step 6: peer review meeting to validate the final outcome. Step 7: completion of RC delineation atlases. Results A new ontology of structure sets was defined and the related table of anatomical boundaries was generated. The major modifications were about the lateral lymph nodes and the ischio-rectal fossa delineation. Seven RC cases were made available online as consultation atlases. Conclusion The definition of international CG for RC delineation endorsed by international experts might support a future homogeneous comparison between clinical trial outcomes