Equivalent Biological Effective Dose (BEDeq) Modeling of Tumor Control Probability in Partial Breast Irradiation

2005 ◽  
Vol 63 ◽  
pp. S253 ◽  
Author(s):  
S.C. Lymberis ◽  
B.S. Rosenstein ◽  
G. Jozsef ◽  
S.C. Formenti ◽  
J. DeWyngaert
Keyword(s):  
Effective Dose ◽  
Partial Breast Irradiation ◽  
Tumor Control ◽  
Tumor Control Probability ◽  
Breast Irradiation ◽  
Biological Effective Dose

scholarly journals Preliminary Report of Partial-breast Irradiation Following Neoadjuvant Chemotherapy from COMBAT-NEO: Clinical Outcome of Multicatheter BrAchyTherapy after NEOadjuvant Chemotherapy

2021 ◽  
pp. 149-155
Author(s):  
Kazuhiko Sato ◽  
Hiromi Fuchikami ◽  
Naoko Takeda ◽  
Takahiro Shimo ◽  
Masahiro Kato ◽  
...  
Keyword(s):  
Neoadjuvant Chemotherapy ◽  
Clinical Outcome ◽  
Adverse Events ◽  
Small Sample ◽  
Single Stage ◽  
Partial Breast Irradiation ◽  
Wound Complications ◽  
Tumor Control ◽  
Breast Irradiation

Background: Breast-conserving therapy (BCT) with partial-breast irradiation (PBI) has become a standard alternative to whole-breast irradiation. Recently, neoadjuvant chemotherapy (NACT) has been widely performed for early breast cancer. Although BCT using perioperative PBI decreased invasiveness and geographic miss, risks of adverse events and local recurrence remain a concern for patients receiving NACT. Thus, a prospectively registered study, the Clinical Outcome of Multicatheter BrAchyTherapy after NEOadjuvant chemotherapy (COMBAT-NEO), was conducted.Methods: Patients who underwent BCT using multicatheter-interstitial brachytherapy (MIB) by intraoperative catheter implant were analyzed. Early and late adverse events (AEs) including higher grade skin toxicities and wound complications, and tumor control of patients receiving NACT were evaluated in comparison with adjuvant chemotherapy (ACT) and no chemotherapy (no-CT).Results: Between April 2017 and February 2020, 265 consecutive patients who received single-stage BCT were evaluated, including 13 NACT (4.9%), 68 ACT (25.7%), and 184 no-CT (69.4%). The median follow-up time and age were 30.0 months and 59.0 years, respectively. All patients were followed up for at least 12 months. Although AEs in NACT, ACT, and no-CT were observed in 1 (7.7%), 5 (7.4%), and 11 (6.0%) patients, respectively (p = 0.91) and there was no acute AE in NACT patients. Overall, 3 (1.1%) ipsilateral and 1 (0.4%) contralateral breast tumor recurrences were observed in no-CT patients. There were no regional and distant recurrences.Conclusion: Although this pilot study was based on a small sample size with short follow-up, these preliminary results support the study of a single-stage BCT with MIB-PBI following NACT.

Patient-reported outcomes (PROs) in NRG oncology/NSABP B-39/RTOG 0413: A randomized phase III study of conventional whole breast irradiation (WBI) versus partial breast irradiation (PBI) in stage 0, I, or II breast cancer.

2019 ◽  
Vol 37 (15_suppl) ◽  
pp. 508-508 ◽  
Author(s):  
Patricia A. Ganz ◽  
Reena S. Cecchini ◽  
Julia R. White ◽  
Frank Vicini ◽  
Thomas B. Julian ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Treatment Outcomes ◽  
Pain Scale ◽  
Local Tumor Control ◽  
Phase Iii ◽  
Partial Breast Irradiation ◽  
Tumor Control ◽  
Breast Irradiation ◽  
Related Symptom ◽  
Patient Reported

508 Background: PBI is an alternative to WBI, with potentially greater therapy (tx) compliance, and better integration with chemotherapy (CTX). NSABP B-39/RTOG 0413 clinical outcome results from 2018 did not show equivalence of PBI to WBI in local tumor control; PBI was statistically inferior, but with clinically small differences. PBI may be an acceptable alternative to WBI for some women. Understanding cosmesis and quality of life (QOL) treatment outcomes is important. Methods: B-39/0413 included a prospective QOL substudy with PRO evaluation of breast cancer treatment outcomes (cosmesis, function, pain) and fatigue using BCTOS and SF-36 vitality scales. Secondary QOL parameters included treatment related symptoms, perceived convenience of care, and the BPI pain scale. The study sample was stratified by CTX or not, as CTX is given before WBI but after PBI. PRO assessments occurred before randomization, the last day of adjuvant tx [CTX or radiation], 4 wks later, and 6, 12, 24, and 36 mo later. Primary aims included comparisons of change in fatigue from baseline to end of tx and equivalency of change in cosmesis from baseline to 36 mo for PBI v WBI. Separate analyses were done for CTX and non-CTX pts, controlling for axillary dissection. Each comparison used α=0.0125. Planned sample size was 964. Results: From 3-23-05 to 5-27-09, 975 pts were enrolled in the PRO study; 950 had follow-up data. 504 did not receive CTX and 446 received CTX. In non-CTX pts, PBI had less fatigue (p=0.011) and did not meet criteria for cosmesis equivalence (97.5% CI, -0.02 to 0.22; ∆=0.20). In CTX pts, PBI had worse fatigue (p=0.011) and equivalent cosmesis to WBI (97.5% CI, -0.09 to 0.21; ∆=0.24). In both groups, PBI pts reported less pain at end of tx. In non-CTX pts, PBI had more pain at 36 mo but in CTX pts, there was no difference. Convenience of care and treatment related symptom outcomes will be presented. Conclusions: In non-CTX pts, PBI is more convenient with less fatigue and slightly poorer cosmesis at 36 mo. Cosmesis was equivalent at 36 mo in CTX pts. Support: U10CA180868, -180822, UG1CA189867. Clinical trial information: NCT00103181.

scholarly journals Biologically Effective Dose (BED) or Radiation Biological Effect (RBEf)?

2020 ◽  
Author(s):  
Terman Frometa-Castillo ◽  
Anil Pyakuryal ◽  
Amadeo Wals-Zurita ◽  
Asghar Mesbahi
Keyword(s):  
Effective Dose ◽  
Biological Effects ◽  
Tumor Control ◽  
Biologically Effective Dose ◽  
Tumor Control Probability ◽  
Linear Quadratic ◽  
Cell Repair ◽  
A Cell ◽  
Biological Dose ◽  
S Model

The current radiosensitive studies are described with linear-quadratic (LQ) cell survival (S) model for one fraction with a dose d. As result of assuming all sublethally damaged cells (SLDCs) are completely repaired during the interfractions, that is, no presence of SLDCs, the survived cells are calculated for a n-fractionated regimen with the LQ S(n,D) model. A mathematically processed subpart of LQS(n,D) is the biologically effective dose (BED) that is used for evaluating a so-called “biological dose.” The interactions of ionizing radiation with a living tissue can produce partial death or sublethal damage from healthy or sublethally damaged cells. The proportions of the killed and sub-lethally damaged cells define the radiation biological effects (RBEfs). Computational simulations using RBEFs for fractionated regimens let calculating tumor control probability. While the derivation of the LQ S(n,D) considers a 100% cell repair, that is, 0% of sublethally damaged cells (SLDCs), the radiobiological simulators take into account the presence of SLDCs, as well as a cell repair <100% during the interfractions and interruption. Given “biological dose” does not exist, but RBEf, there was need for creating the BED. It is shown how some uses of BED, like the derivation of EQ2D expression, can be done directly with the LQ S(n,D).

Sign in / Sign up

Export Citation Format

Share Document