Hypofractionated whole breast irradiation: new standard in early breast cancer after breast-conserving surgery

Postoperative Complications Following Lumpectomy With Intraoperative X-Ray Radiation Therapy: A Retrospective Comparative Study

BACKGROUND

Lumpectomy with intraoperative radiation (IORT) is a relatively new modality for the treatment of early breast cancer. IORT delivers targeted radiation to the tumor bed and obviates the need for external beam radiation (EBRT) in 85% of the cases. IORT is being used increasingly around the world, however information regarding early and late postoperative complications associated with the procedure is limited.

AIM

To describe and compare complication rates after lumpectomy and IORT with those seen after lumpectomy and EBRT or lumpectomy alone.

METHODS

Clinical, demographic, and histopathological data were collected from electronic medical records and a retrospectively maintained database. Postoperative complications were compared for patients undergoing lumpectomy with IORT, lumpectomy with EBRT, and lumpectomy alone over the same period.

RESULTS

A total of 445 patients were included in the study: 113 underwent lumpectomy with IORT, 253 had lumpectomy followed by EBRT, and 79 had Lumpectomy alone. Postoperative seroma was documented in 74 patients (65%) after IORT,87 (34%) after EBRT, and 9 (11%) after lumpectomy alone (P = .000). Surgical site infection requiring antibiotic treatment was diagnosed in 26 patients (23%) after IORT, 38 (15%) after EBRT, and 5 (6%) after lumpectomy alone (P = .013). Postoperative erythema was documented in 39 patients (34%) after IORT, 40 (16%) after EBRT, and 5 (6%) after lumpectomy alone (P = .000). Postoperative minor complications such as scar and breast deformity, edema, Mondor's syndrome, and chronic tenderness, were documented in 62 patients (55%) after IORT, 119 (47%) after EBRT, and 13 (17%) after lumpectomy alone (P = .000). The average follow-up was 14 months.

CONCLUSIONS

IORT is associated with an increased rate of postoperative complications compared to EBRT or lumpectomy alone. Most complications are minor and transient. We hypothesize that the increased occurrence of complications may also be attributed to overreporting, which is associated with the introduction of a new technology. Educating physicians and patients about potential complications and their course may help establish expectations and improve the management of postoperative complications.

Incidental Axillary Dose of Tomotherapy in Hypofractionated Whole Breast Radiotherapy for Early Breast Cancer: A Dosimetrical Analysis

Background and Objectives: Intensity-modulated radiation therapy (IMRT) is becoming a more common method of performing whole breast irradiation (WBI) for early breast cancer. This study aimed to examine the incidental dose to the axillary region using tomotherapy, a unique form of IMRT. Patients and Methods: This study included 30 patients with early-stage breast cancer who underwent adjuvant WBI using TomoDirect IMRT. A hypofractionation scheme of 42.4 Gy delivered in 16 fractions was prescribed. The plan comprised of two parallel-opposed beams, along with two additional beams positioned anteriorly at gantry angles of 20° and 40° from the medial beam. The incidental dose received at axillary levels I, II, and III was evaluated using several dose-volume parameters. Results: The study participants had a median age of 51 years, and 60% had left-sided breast cancer. The mean dose of the axilla for levels I, II, and III were 15.5 ± 4.8 Gy, 14.9 ± 4.2 Gy, and 1.5 ± 1.6 Gy, respectively. Adequate coverage of the axilla, defined as V95%[%], was achieved for 4.7 ± 3.9%, 4.8 ± 3.7%, and 0 ± 0% for levels I, II, and III, respectively. The results were compared with those of previously published studies, and the axillary mean dose and V95%[%] of TomoDirect IMRT were low, comparable to other IMRT techniques, and lower than those of traditional tangential therapy. Conclusions: While incidental axillary radiation during WBI has been proposed to assist in regional disease control, the TomoDirect plan was demonstrated to decrease this dose, and a hypofractionation scheme would further lower its biological effectiveness. Future clinical studies should incorporate dosimetrical analysis of incidental axillary dose, in order to facilitate hypofractionated IMRT planning with risk-adjusted axilla coverage in early breast cancer.

Guidelines for breast cancer management in Bosnia and Herzegovina

Breast cancer is the most common cancer among women. In Bosnia and Herzegovina, accurate data on the status of breast cancer are lacking due to the absence of a central registry. Multiple international guidelines imply that institutions that monitor breast cancer patients should have optimal therapeutic options for treatment. In addition, there have been several international consensus guidelines written on the management of breast cancer. Application of consensus guidelines has previously been demonstrated to have a positive influence on breast cancer care. The importance of specialty breast centers has previously been reported. As part of the 2021 Bosnian-Herzegovinian American Academy of Arts and Sciences (BHAAAS) conference in Mostar, a round table of multidisciplinary specialists from Bosnia and Herzegovina and the diaspora was held. All were either members of BHAAAS or regularly participate in collaborative projects. The focus of the consortium was to write the first multidisciplinary guidelines for the general management of breast cancer in Bosnia and Herzegovina. Guidelines were developed for each area of breast cancer treatment and management. These guidelines will serve as a resource for practitioners managing breast cancer in the Bosnia and Herzegovina region. This might also be of benefit to the ministry of health and any future investors interested in developing breast cancer care policies in this region of the world.

Cost-effectiveness of Post-Mastectomy Radiotherapy (PMRT) for breast cancer in India: An economic modelling study

Background

The role of post-mastectomy radiotherapy (PMRT) for breast cancer is controversial when 3-or-less lymph nodes are metastatic. Apart from local control, survival and toxicity, cost also plays an important role in decision-making.

Methods

A Markov model was designed to assess cost, health outcomes and cost-effectiveness of different radiotherapy techniques for management of PMRT patients. Thirty-nine scenarios were modelled based on type of radiotherapy, laterality, pathologic nodal burden, and dose fractionation. We considered a societal perspective, lifetime horizon and a 3% discount rate. The data on quality of life (QoL) was derived using the cancer database on cost and QoL. Published data on cost of services delivered in India were used.

Findings

Post-mastectomy radiotherapy results in incremental quality adjusted life years (QALYs) that ranged from -0.1 to 0.38 across different scenarios. The change in cost ranged from estimated median savings of USD 62 (95% confidence intervals: -168 to -47) to incurring an incremental cost of USD 728 (650-811) across different levels of nodal burden, breast laterality and dose fractionation. For women with node-negative disease, disease-specific systemic therapy remains to be the preferred strategy. For women with node-positive disease, two-dimensional radiotherapy (2DRT) with hypofractionation is the most cost-effective strategy. However, a CT based planning is preferred when maximum heart distance (MHD) >1cm, irregular chest wall contour and inter-field separation >18cm.

Interpretation

PMRT is cost-effective for all node-positive patients. With similar toxicity and effectiveness profile compared with conventional fractionation, moderate hypofractionation significantly reduces the cost of treatment and should be the standard of care. Conventional techniques for PMRT are cost-effective over newer modalities which provide minimal additional benefit, at high cost.

Funding

The funding to collect primary data for study was provided by Department of Health Research, Ministry of Health and Family Welfare, New Delhi, wide letter number F. No. T.11011/02/2017-HR/3100291.

Prognostic role of radiotherapy in low-risk elderly breast cancer patients after breast-conserving surgery: a cohort study

BACKGROUND

Previous research suggested that radiotherapy (RT) had a small absolute benefit in patients with low-risk breast cancer over the age of 65. To reduce the patient's treatment burden and cost, as well as the damage to normal tissue, this study sought to explore the prognostic role of RT after breast-conserving surgery (BCS) in elderly patients.

METHODS

Patients who were aged ≥65 years, stage T1N0M0, and estrogen receptor/progesterone receptor positive (ER+/PR+) were included in this study. Age, marital status, histology, race, grade, human epidermal growth factor receptor 2 (HER2), subtype, treatment method, and survival were also collected from the Surveillance, Epidemiology, and End Results (SEER) database from 2004 to 2015. We compared overall survival (OS) and breast cancer-specific survival (BCSS) before and after propensity score matching (PSM) in the patients who underwent BCS with or without RT. Kaplan-Meier method and Cox proportional hazards regression analyses were used in our study.

RESULTS

The data of 3,623 patients were analyzed in this study. Among them, 2,851 (78.69%) patients had received RT. The multivariate analyses before PSM showed that RT resulted in better OS [hazard ratio (HR) 0.51, 95% confidence interval (CI): 0.42-0.62, P<0.001], and BCSS (HR 0.40, 95% CI: 0.27-0.58, P<0.001). The multivariate analyses after PSM (n=1,538) confirmed that patients who received RT (n=769) had a longer survival time than those who did not (n=769) (OS: HR 0.73, 95% CI: 0.57-0.95, P=0.018; and BCSS: HR 0.57, 95% CI: 0.35-0.93, P=0.025). The survival analysis showed that patients receiving RT had a better OS (P=0.028) and BCSS (P=0.016) than those who did not receive RT. However, there were no significant differences in patients' OS and BCSS with or without RT across the different age subgroups (P>0.05).

CONCLUSIONS

In our study, patients who received RT had a longer survival time. However, the age subgroup analysis showed that RT did not have any survival benefit in elderly patients with T1N0M0 and ER+/PR+ breast cancer. Furthermore, at the age of 65-69 years, the P value for OS approached 0.05, which suggests that the decision to administer RT in this patient group should be made based on each patient's condition.

SKIN AND SUBCUTANEOUS ADIPOSE TISSUE DAMAGE AFTER RADIATION THERAPY IN BREAST CANCER PATIENTS

The analysis of long-term researches of the pathological changes arising in soft tissues at patients with a breast cancer as a result of radical surgical treatment and adjuvant radiotherapy is carried out in work. The article shows that the standard approach to postoperative radiation therapy, which is based only on the prevalence of the primary tumor process is not always justified. Very often it leads to excessive radiation load on the patient's body and the development of local acute and chronic radiation reactions of the skin, subcutaneous tissue and other soft tissues.In this regard, the question of differentiated purpose of radiotherapy acquires special value first of all at patients with small primary prevalence of tumor process. The paper presents the results of studies to study changes in the anterior chest wall in patients with breast cancer. In relation to the conduct of adjuvant radiotherapy more often need to use the concept of personalized radiation therapy. Radical operation, post-radiation early and late pathological changes in soft tissues, disturbance of microcirculation of lymph and blood, disturbance of innervation of vessels of an upper extremity, peripheral nerves in system of a cervical and plexus plexus, leads to intensive degen-erative and dystrophic changes in soft tissues of the upper. and causes morphological changes in them and further progression of reflex neurovascular and neurodystrophic disorders. Based on the data of adverse effects of radio-therapy on the skin and surrounding tissues, as well as to reduce excessive radiation exposure to the patient's body, a differentiated approach to the appointment of adjuvant radiation therapy.

Young Women With Breast Cancer: Treatment, Care, and Nursing Implications

BACKGROUND

Young women with breast cancer (YWBC) are more likely to have aggressive disease, carry mutations for hereditary cancer genes, and experience higher mortality. They also may face reduced fertility because of the toxicity of chemotherapy.

OBJECTIVES

This article aims to present a review of YWBC treatments, sequelae of treatment, and psychosocial challenges.

METHODS

The authors performed a review of guideline-supported treatment options, patient resources, and nursing implications.

FINDINGS

Because of high-risk cancers and a lack of specific treatment guidelines, healthcare providers may consider aggressive treatments for younger patients. However, studies indicate that the foundation for treatment decisions for YWBC are best based on disease stage and National Comprehensive Cancer Network guidelines.

The Acute and Late Toxicities of MRI-Guided External Beam Partial Breast Irradiation Delivered Using a Once-Per-Day Regimen

Background and Purpose

The use of external beam accelerated partial breast irradiation (APBI) using a twice-per-day regimen has raised concerns about increase rates of late toxicities. We compared toxicity outcomes of external beam APBI using a once-per-day regimen and accelerated hypofractionated whole breast irradiation (AWBI) in patients with early-stage breast cancer.

Materials and Methods

This was a single-institution, retrospective cohort study. Patients aged ≥50 years with pTisN0 or pT1N0 breast cancer who underwent breast-conserving surgery and adjuvant radiotherapy were included. APBI was delivered at 38.5 Gy in 10 fractions once daily using magnetic resonance imaging (MRI)-guided radiotherapy only to patients who were strictly “suitable”, according to the ASTRO-APBI guidelines. AWBI was delivered at 40.5–43.2 Gy in 15 or 16 fractions with or without a boost.

Results

Between October 2015 and December 2018, 173 and 300 patients underwent APBI and AWBI, respectively. At a median follow-up of 34.9 months (range 7.1 to 55.4 months), the 3-year recurrence-free survival rates of the APBI and AWBI groups were both 99.2% (p=0.63). Acute toxicities were less frequent in the APBI than AWBI group (grade 1: 95 [54.9%] vs. 233 [77.7%] patients; grade 2: 7 [4.0%] vs. 44 [14.7%] patients; no grade ≥3 toxicities were observed in either group, p<0.001). Late toxicities were less common in the APBI than AWBI group (grade 1: 112 [64.7%] vs. 197 [65.7%] patients; grade 2: 9 [5.2%] vs. 64 [21.3%] patients; grade 3: 0 vs. 5 [1.7%] patients, p<0.001). Multivariate analysis showed that APBI was significantly associated with fewer late toxicities of grade ≥2 compared with AWBI (odds ratio 4.17, p=0.006).

Conclusion

Once-per-day APBI afforded excellent locoregional control and fewer toxicities compared with AWBI. This scheme could be an attractive alternative to AWBI in patients who meet the ASTRO-APBI guidelines.

Breast-conserving radiotherapy with simultaneous integrated boost; field-in-field three-dimensional conformal radiotherapy versus inverse intensity-modulated radiotherapy - A dosimetric comparison: Do we need intensity-modulated radiotherapy?

Background and Purpose:

To examine the feasibility of improving breast-conserving radiotherapy with simultaneous integrated boost (SIB) and analyzing the efficiency of forward versus inverse intensity-modulated radiotherapy (IMRT) techniques in providing the same.

Materials and Methods:

Three-dimensional conformal radiotherapy (3DCRT) field-in-field (FIF) plans with simultaneous and sequential boost and IMRT SIB plans were generated for the datasets of 20 patients who had undergone breast-conserving surgery. The 3 plans were compared dosimetrically for efficiency in terms of planning target volume (PTV) coverage (PTV 95%), homogeneity and conformity, dose delivered to ipsilateral/contralateral lungs (I/L: V10, V20, C/L: Vmean, V5), heart and contralateral breast (Vmean, V30 for heart and Vmean, V1, V5 for C/L breast).

Results:

The FIF 3DCRT plan with SIB (PLAN B) was more homogeneous than the classical technique with sequential boost (PLAN A). There were less hot spots in terms of Dmax (63.7 ± 1.3) versus Dmax (68.9 ± 1), P < 0.001 and boost V107%, B (0.3 ± 0.7) versus A (3.5 ± 5.99), P = 0.001. The IMRT SIB (PLAN C) did not provide any significant dosimetric advantage over the 3DCRT SIB technique. IMRT SIB plan C was associated with increased dose to contralateral lung in-terms of V5 (10.35 +/- 18.23) vs. (1.13 +/- 4.24), P = 0.04 and Vmean (2.12 ± 2.18) versus Vmean (0.595 ± 0.89), P = 0.008. There was 3-fold greater exposure in terms of Monitor Unit (MU) (1024.9 ± 298.32 versus 281.05 ± 20.23, P < 0.001) and treatment delivery time.

Conclusions:

FIF 3DCRT SIB provides a dosimetrically acceptable and technically feasible alternative to the classical 3DCRT plan with sequential boost for breast-conserving radiotherapy. It reduces treatment time by 2 weeks. IMRT SIB does not appear to have any dosimetric advantage; it is associated with significantly higher doses to contralateral lung and heart and radiation exposure in terms of MU.

Practical consensus recommendations regarding role of postmastectomy radiation therapy

The use of radiation therapy after mastectomy (PMRT) has been limited to those patients who are at significant risk of cancer recurring in the chest wall or in the nodal basins. The use of PMRT has been widely accepted for patients with four or more positive lymph nodes,^[1],[2] but there is still controversy regarding the value of PMRT for those with one to three positive nodes. This expert group used data from published literature, practical experience and opinion of a large group of academic oncologists to arrive at these practical consensus recommendations for the benefit of community oncologists.

Hypo- vs. normofractionated radiation therapy in breast cancer: A patterns of care analysis in German speaking countries

Aim and background

To assess the use of hypofractionated (HG-RT) versus normofractionated radiation therapy (NF-RT) in Breast Cancer in German speaking countries.

Materials and methods

Between July 2017 and August 2017, an email-based survey was sent to all 1408 physicians that are members of the German Society of Radiation Oncology (DEGRO). The survey was completed by 180 physicians including 10 private practice owners and 52 heads of departments. The majority (82.1%) of the participants had >15 years of experience in radiation therapy (RT).

Results

The majority (83.9%) of the heads of the departments agreed on using the normofractionated regimen of RT as standard treatment for breast cancer. Several physicians were skeptical about HF-RT with 6.5% of the heads refusing to use HF-RT. 40.3% of the departments had not seen the new German guidelines suggesting HF-RT as the standard treatment for all patients as positive or merely adopted a neutral position toward the guidelines (33.9%). The main points of criticism were increased side effects, an impaired toxicity profile and insufficient data. Most departments (46.8%) that perform HF-RT do so in an individual based manner.

Conclusions

HF-RT remains controversial in German speaking countries. Our data shows that NF-RT remains the predominant method of treatment. HF-RT is only used in a defined group of patients as most German physicians agree that particular patients, especially those at higher risk of RT late effects, may benefit from a less intense, extended fractionation schedule.

Loco-regional outcomes of adjusted breast radiotherapy with conventional fractionation after breast conserving surgery: De-escalation of whole breast irradiation dose

We compared the cumulative incidence of ipsilateral breast tumor recurrence (IBTR) between 2 whole breast irradiation (WBI) dose range with conventional fractionation.We retrospectively reviewed 1122 patients who received WBI at 2 institutions between 2004 and 2012. One institution delivered WBI 41.4 to 45 Gy followed by boost 14 to 18 Gy (adjusted group), while the other delivered WBI 50 to 50.4 Gy followed by boost 10 Gy (standard group).The median follow-up period was 85 months. The 10-year cumulative incidence in all patients was 6.1% (95% confidence interval [CI]: 4.3%-8.4%) for IBTR and 3.0% (95% CI: 1.7%-4.8%) for regional recurrence. The 10-year cumulative incidence of IBTR was not significantly influenced by WBI dose (6.3% in the adjusted group vs 5.2% in the standard group, P = .136). Comparable IBTR rates between the 2 groups were observed regardless of clinical and pathological factors. The WBI dose was not significantly associated with the 10-year cumulative incidence of regional recurrence in these groups (3.5% in the adjusted group vs 0.5% in the standard group, P = .214).De-escalated WBI doses while intensifying tumor bed boost did not compromise local and regional outcomes compared to standard group.

Hybrid planning techniques for hypofractionated whole-breast irradiation using flattening filter-free beams

OBJECTIVE

The aim of this study was to assess the feasibility of flattening filter-free (FFF) photon beams in hybrid intensity-modulated radiation therapy (H-IMRT) and hybrid volumetric modulated arc therapy (H-VMAT) for left-sided whole-breast radiation therapy with a boost volume (RT) using a hypofractionated dose regimen.

PATIENTS AND METHODS

RT plans of 25 patients with left-sided early-stage breast cancer were created with H‑IMRT and H‑VMAT techniques under breath-hold conditions using 6‑MV FFF beams. In hybrid techniques, three-dimensional conformal radiotherapy (3DCRT) plans were kept as base-dose plans for the VMAT and IMRT plans. In addition, H‑IMRT in step-and-shoot mode was also calculated to assess its achievability with FFF beams.

RESULTS

All hybrid plans achieved the expected target coverage. H‑VMAT showed better coverage and homogeneity index results for the boost target (p < 0.002), while H‑IMRT presented better results for the whole-breast target (p < 0.001). Mean doses to normal tissues were comparable between both plans, while H‑IMRT reduced the low-dose levels to heart and ipsilateral lung (p < 0.05). H‑VMAT revealed significantly better results with regard to monitor units (MU) and treatment time (p < 0.001).

CONCLUSION

The 6‑MV FFF beam technique is feasible for large-field 3DCRT-based hybrid planning in whole-breast and boost planning target volume irradiation. For breath-hold patients, the H‑VMAT plan is superior to H‑IMRT for hypofractionated dose regimens, with reduced MU and treatment delivery time.

Symptom palliation of hypofractionated radiotherapy for patients with incurable inflammatory breast cancer

Background

Incurable inflammatory breast cancer (IBC) patients occasionally suffer from general symptoms such as breast pain, bleeding, ulceration, and discharge, and thus require palliative radiotherapy (RT). Hypofractionated RT has many advantages in palliative settings, but very few studies on IBC have been conducted. This study was conducted to evaluate the effects of hypofractionated RT on symptomatic IBC patients.

Methods

Twenty-two patients with IBC who underwent hypofractionated palliative RT between 2010 and 2016 were retrospectively analyzed. RT was performed at a total dose of 42.5–55 Gy with 2.5–3 Gy per fraction. The treatment effects were evaluated with respect to symptom improvement, tumor response, and treatment-related toxicity.

Results

The main symptoms that the patients complained of before RT were pain, bleeding, and discharge. According to the percentage of symptom relief compared with pre-RT symptoms, the number of patients with < 30, 30–70%, and ≥ 70% were 2 (9.1%), 7 (31.8%), and 13 (59.1%), respectively. Eighteen (81.8%) patients showed tumor response. No patient experienced grade 3 or higher acute or chronic toxicity during a median follow-up period of 13 months. In univariate analysis, symptom type was a significant factor for predicting the degree of symptom relief. Meanwhile, RT field and C-reactive protein increase were significant factors for predicting the incidence of radiation-induced skin toxicity.

Conclusions

Hypofractionated RT could safely and effectively relieve symptoms among incurable symptomatic IBC patients.

MicroRNA-21 is Required for Hematopoietic Cell Viability After Radiation Exposure

PURPOSE

Radiation therapy is an essential intervention used in the treatment of more than half of cancer patients. With the increasing use of hypofractionated radiation regimens, concurrent use of radiation and chemotherapy, targeted agents and immunotherapy, the risk of radiation-induced toxicities is increased. However, much remains unknown about the molecular underpinnings responsible for radiation-induced toxicity. MicroRNA (miRNA) are small, non-coding RNA involved in post-transcriptional regulation of gene expression. miR-21 is an oncomiR that is dysregulated in a significant fraction of human malignancies, and its overexpression is linked to poor overall survival, chemoresistance, and radioresistance in several human cancers. However, the contribution of miR-21 in governing radiation sensitivity in normal, untransformed cells, and the impact of silencing this miRNA in normal tissues remains largely unexplored.

MATERIALS AND METHODS

miR-21 levels were evaluated in tissues by qRT-PCR without and after total body irradiation (TBI). Mice lacking miR-21 were genetically engineered, subjected to TBI, and monitored for survival. Hematopoietic stem and progenitor cell (HSPC) numbers and function were assessed using flow cytometry, histology, complete blood cell counts, and bone marrow transplantation.

RESULTS

miR-21 expression was increased in radiosensitive tissues, but not in radioinsensitive tissues following TBI in wild-type mice, suggesting it may have a critical function in the normal tissue response to irradiation. Compared to wild-type mice, mice lacking one or both alleles of miR-21 showed reduced numbers of HSPCs and increased sensitivity to an LD_50/30 dose of TBI with evidence of bone marrow failure. Transplantation of wild-type bone marrow into irradiated miR-21-deficient mice rescued the mice from death.

CONCLUSIONS

Our data identify miR-21 as a critical component of HSPC viability and essential for bone marrow recovery following irradiation. Further investigation is warranted to determine whether miR-21 can be used to stratify patients at risk for hematopoietic toxicity following irradiation.

Results of a nationwide survey on Japanese clinical practice in breast-conserving radiotherapy for breast cancer

The Breast Cancer Group of the Japanese Radiation Oncology Study Group conducted a nationwide questionnaire survey on the clinical practice of postoperative radiotherapy for breast-conserving treatment for breast cancer. This questionnaire consisted of 18 questions pertaining to the annual number of treated patients, planning method, contouring structure, field design, dose-fractionated regimen, application of hypofractionated radiotherapy, boost irradiation, radiotherapy for synchronously bilateral breast cancer, and accelerated partial breast irradiation. The web-based questionnaire had responses from 293 Japanese hospitals. The results indicated the following: treatment planning is performed using relatively similar field designs and delivery methods; the field-in-field technique is used at more than one-third of institutes; the commonest criteria for boost irradiation is based on the surgical margin width (≤5 mm) and the second commonest criteria was age (≤40 or ≤50 years), although some facilities applied a different age criterion (>70 years) for omitting a tumor bed boost; for conventional fractionation, almost all institutes delivered 50 Gy in 25 fractions to the conserved whole breast and 10 Gy in 5 fractions to the tumor bed. This survey revealed that 43% of hospitals offered hypofractionated radiotherapy, and the most common regimens were 42.56 Gy in 16 fractions for whole-breast irradiation and 10.64 Gy in 4 fractions for boost irradiation. Almost all of the facilities irradiated both breasts simultaneously for synchronously bilateral breast cancer, and accelerated partial breast irradiation was rarely offered in Japan. This survey provided an overview of the current clinical practice of radiotherapy for breast-conserving treatment of breast cancer in Japan.

Evaluation of tissue computed tomography number changes and dosimetric shifts after conventional whole-breast irradiation in patients undergoing breast-conserving surgery

The aim of this study was to assess tissue computed tomography (CT) number changes and corresponding dosimetric shifts in repeatedly performed simulation CT (re-sim CT) scans after conventionally fractionated irradiation in breast cancer patients. A total of 28 breast cancer patients who underwent breast-conserving surgery were enrolled in this study. All the patients had received 50.4 Gy of conventional whole-breast irradiation (WBI) and underwent re-sim CT scans for tumor bed boost. For evaluation of dosimetric shifts between initial and re-sim CT scans, electron boost plans in the same field size with the same monitor unit with source-to-skin distance of 100 cm were conducted. Dosimetric parameters (V_105%, V_103%, V_100%, V_98%, V_95%, V_90%: V_x% indicates volumes which receive X% of prescribed doses) between initial and re-sim CT scans were compared. The CT number data (CT_mean, CT_max, CT_min) of the original and irradiated CT (re-sim CT) scans from each representative structure (lung, rib bone, soft tissue, muscle, etc.) were examined and recruited. CT numbers showed highly variable changes. Soft tissue CT_mean and muscle CT_max/CT_min showed statistically and significantly increased values in the CT (re-sim CT) compared to the original CT scans. Rib bone CT_mean/CT_min showed statistically and significantly decreased values in the re-sim CT compared to the original CT scans. Other CT number values showed no statistically significant changes. Among the dosimetric parameters, only V_105% (p = 0.015, mean = 3.07 cc versus 1.63 cc) and V_103% (p = 0.017, mean = 13.8 cc versus 11.9 cc) exhibited statistically increased values in the re-sim CT compared to the original CT scans. CT number changes after conventional WBI were different according to tissue component. For electron boost plans, the implementation of a re-sim CT might be helpfully considered because significant dosimetric factor changes were observed especially in the high-dose areas (hot spots: V_105% and V_103%).

Preliminary toxicity results using partial breast 3D-CRT with once daily hypo-fractionation and deep inspiratory breath hold

BACKGROUND

To evaluate the clinical outcomes of patients treated with 3D conformal Hypo-fractionated, deep Inspiratory breath-hold (DIBH), Partial breast radiotherapy, termed "HIP." HIP was implemented to merge the schedule of once-daily breast hypofractionation with partial breast treatment.

METHODS

We identified 38 breast cancers in 37 patients from 2013 to 2014 treated at our institution with HIP following lumpectomy for early stage breast cancer. Patients received a hypo-fractionated course (≤ 20 fractions) of once daily radiation to the partial breast (lumpectomy cavity + margin) utilizing DIBH regardless of laterality. Clinical and treatment-related characteristics were obtained, including target volume and organ at risk (OAR) dosimetric characteristics. Patients were followed clinically and with at least yearly mammograms for up to 36 months (range 5-36 months). Acute and late toxicity was scored using the Common Terminology Criteria for Adverse Events (CTCAE) v4.03.

RESULTS

Patients received a median dose of 42.56 Gy in 16 Fractions (Fx) (range 40.05-53.2 Gy; and 15-20 Fx). OAR doses were low, with a mean heart dose of 0.37 Gy, an ipsilateral lung V20 mean of 4%, and a contralateral lung V5 of 1%. Acute toxicity (≤ grade 2) was present in 79% (n = 30) of the cases, with dermatitis being the most common finding (63%). Late grade 1-2 toxicity was present in 42% (n = 16) of the cases, with hyperpigmentation being the most common finding (n = 9). There were no severe acute or late toxicities (≥ grade 3). At a median follow up of 21 months, there were no local, regional, or distant failures.

CONCLUSIONS

We report limited toxicity in this low risk cohort of patients with early stage breast cancer treated with HIP, a unique and logical combination of 3-D conformal external beam radiotherapy, moderate hypo-fractionation, and DIBH.

Should age impact breast cancer management in young women? Fine tuning of treatment guidelines

Despite breast cancer being uncommon in young women, it is still the most frequent cancer diagnosed in women aged 15–39 years, and the leading cause of death in this age group in high-income countries, after accidents and self-injury. The present review summarizes the most recent guidelines and offers an expert perspective on the many challenges associated with treatment of young women with breast cancer. We will especially focus on early breast cancer, exploring the specificities of the diagnostic process, imaging techniques, locoregional and systemic treatments, and the added value of dedicated multidisciplinary teams. Specific differences in adjuvant treatment between premenopausal and postmenopausal women, especially regarding endocrine therapy, will be addressed in detail. Research questions and current gaps in important fields, such as the paucity of age-specific data regarding antihuman epidermal growth factor receptor 2 (anti-HER2) therapy and gene panels such as OncotypeDX or MAMMAPRINT will be highlighted. A consistent part of this review is dedicated to the issues defining ‘young women’, such as fertility preservation, managing long-term side effects of oncological treatments and genetic counselling, by detailing current strategies and future perspectives.

Which Patients with Left Breast Cancer Should be Candidates for Heart-Sparing Radiotherapy?

Purpose

This study aimed to identify risk factors that have significant interaction with radiation exposure to the heart, and thus to determine candidates for heart-sparing radiotherapy (RT) among women with left breast cancer.

Methods

We identified 4,333 patients who received adjuvant RT following breast-conserving surgery for ductal carcinoma in situ or invasive breast cancer from 1996 to 2010. Incidence rates of cardiovascular disease were compared between left-sided and right-sided RT, and stratified by age and risk factors such as body mass index (BMI), smoking, hyperlipidemia, hypertension, diabetes, administration of anthracycline, and trastuzumab.

Results

In all patients, the cumulative incidence of cardiovascular disease was greater in patients treated with left-sided RT than in those treated with right-sided RT, but the difference was not significant (p=0.428). Smoking (hazard ratio [HR], 5.991; 95% confidence interval [CI], 2.109-17.022; p=0.002) and hyperlipidemia (HR, 5.567; 95% CI, 3.235-9.580; p<0.001) were the most powerful risk factors for cardiovascular disease. There was no significant factor that further increased the risk of cardiovascular disease after left breast RT compared to right breast RT.

Conclusion

Although hyperlipidemia and smoking are risk factors for cardiovascular disease, they have not been proven to increase the risk of RT-related cardiovascular disease in Korean women.

Omitting Adjuvant Radiotherapy for Hormone Receptor‒Positive Early-Stage Breast Cancer in Old Age: A Propensity Score Matched SEER Analysis

Purpose

The purpose of this study was to investigate the non-inferiority of omitting radiotherapy (RT) after breast-conserving surgery (BCS) for hormone receptor (HR)‒positive T1N0 breast cancer in elderly women.

Materials and Methods

From 2004 to 2014, HR-positive T1N0 breast cancer patients aged 50 years or older and receiving BCS were retrieved from the Surveillance, Epidemiology, and End

Results

18 database. After propensity score matching between the no-RT and RT groups, univariate and multivariate analyses were performed. Identified prognostic factors were used to stratify the risk groups. In each risk group, 10-year cancer-specific survival (CSS) rates were compared between the no-RT and RT groups.

Results

After propensity score matching, the numbers of patients in the no-RT and RT groups were both 18,586. For patients who satisfied both a tumor size of 1-10 mm and a tumor grade of 1-2, omitting RT did not decrease the CSS rate at any age group, ranging from ≥ 50 to ≥ 85 years; for patients aged ≥ 50 years, the 10-year CSS rates in the no-RT and RT groups were 97.2% and 96.8%, respectively (adjusted hazard ratio, 0.862; p=0.312). However, for patients with a tumor size of 11-20 mm or tumor grade of 3-4, RT significantly increased the CSS rate irrespective of age.

Conclusion

RT after BCS for HR-positive T1N0 breast cancer in elderly women might be omitted without causing a decrease in the CSS rate, but only in patients who satisfy both a small tumor size (≤ 10 mm) and low tumor grade (1-2).

Seroma change during magnetic resonance imaging-guided partial breast irradiation and its clinical implications

Background

To investigate the patterns of post-lumpectomy seroma volume (SV) change and related clinical factors to determine the benefits of adaptive planning in magnetic resonance imaging (MRI)-guided partial breast irradiation (PBI).

Methods

MRI data obtained from 37 women with early breast cancer acquired at simulation and at the 1st, 6th, and 10th fractions were analyzed. The planning target volume (PTV) was defined as unequal margins of 10–15 mm added according to the directional surgical margin status of each seroma. Treatment was performed using a 0.35 T MRI-guided radiotherapy system. Univariate analysis was performed to assess the correlations between SV change rate and clinical factors. Seroma and PTV for adaptive planning were based on the images obtained at the 6th fraction.

Results

The average time intervals between surgery-simulation, simulation-1st, 1st-6th, and 6th-10th fractions were 23.1, 8.5, 7.2, and 5.9 days, respectively. Of the 37 patients, 33 exhibited decreased SV over the treatment period. The mean SV of these 33 patients decreased from 100% at simulation to 60, 48, and 40% at each MRI scan. In most cases (26/33), the logarithm of SV was inversely proportional to the elapsed time from surgery (R² > 0.90, Pearson’s correlation test). The volume of spared normal tissue from adaptive radiotherapy was proportional to the absolute change in SV (R² = 0.89, Pearson’s correlation test).

Conclusion

Seromas exhibit exponential shrinkage over the course of PBI. In patients receiving PBI, frequent monitoring of SV could be helpful in decision-making regarding adaptive planning, especially those with a large seroma.

In Situ Vaccination after Accelerated Hypofractionated Radiation and Surgery in a Mesothelioma Mouse Model

Purpose: How best to sequence and integrate immunotherapy into standard of care is currently unknown. Clinical protocols with accelerated nonablative hypofractionated radiation followed by surgery could provide an opportunity to implement immune checkpoint blockade.Experimental Design: We therefore assessed the impact of nonablative hypofractionated radiation on the immune system in combination with surgery in a mouse mesothelioma model. Blunt surgery (R1 resection) was used to analyze the short-term effect, and radical surgery (R0 resection) was used to analyze the long-term effect of this radiation protocol before surgery.Results: Nonablative hypofractionated radiation led to a specific immune activation against the tumor associated with significant upregulation of CD8⁺ T cells, limiting the negative effect of an incomplete resection. The same radiation protocol performed 7 days before radical surgery led to a long-term antitumor immune protection that was primarily driven by CD4⁺ T cells. Radical surgery alone or with a short course of nonablative radiation completed 24 hours before radical surgery did not provide this vaccination effect. Combining this radiation protocol with CTLA-4 blockade provided better results than radiation alone. The effect of PD-1 or PD-L1 blockade with this radiation protocol was less effective than the combination with CTLA-4 blockade.Conclusions: A specific activation of the immune system against the tumor contributes to the benefit of accelerated, hypofractionated radiation before surgery. Nonablative hypofractionated radiation combined with surgery provides an opportunity to introduce immune checkpoint blockades in the clinical setting. Clin Cancer Res; 23(18); 5502-13. ©2017 AACR.

Possible benefits from post-mastectomy radiotherapy in node-negative breast cancer patients: a multicenter analysis in Korea (KROG 14-22)

PURPOSE

This study was performed to identify a subset of patients who may benefit from post-mastectomy radiotherapy (PMRT) among node-negative breast cancer patients.

MATERIALS AND METHODS

We retrospectively reviewed 1,828 patients with pT1-2N0 breast cancer, treated with mastectomy without PMRT from 2005 to 2010 at 10 institutions. Univariate and multivariate analyses for locoregional recurrence (LRR) and any first recurrence (AFR) were performed according to clinicopathologic factors and biologic subtypes.

RESULTS

During a median follow-up period of 5.9 years (range: 0.7-10.4 years), 98 patients developed AFR (39 isolated LRR, 13 LRR with synchronous distant metastasis, and 46 isolated distant metastasis), and 52 patients developed LRR. The 7-year LRR and AFR rates were 3.8% and 6.7%, respectively. Multivariate analysis revealed that age of ≤ 40 years (p<0.001) and T2 stage (p=0.013) were independent risk factors for LRR. The 7-year LRR rates were 2.5% with no risk factors, 4.5% with one risk factor, and 12.4% with two risk factors. Multivariate analysis for AFR revealed that age of ≤ 40 years (p<0.001), T2 stage (p<0.001), and triple-negative biological subtype (p=0.045) were independent risk factors for AFR. The 7-year AFR rates were 3.9% with no risk factors, 8.4% with one risk factor, and 15.7% with two to three risk factors.

CONCLUSIONS

Mastectomy without PMRT is a sufficient local treatment for pT1-2N0M0 breast cancer. Nevertheless, PMRT might be considered for patients with two or three risk factors, among those of young age, with T2 tumors, and with the triple-negative biological subtype based on LRR and AFR.

Displacement of Surgical Clips during Postoperative Radiotherapy in Breast Cancer Patients Who Received Breast-Conserving Surgery

PURPOSE

Surgical clips are used as a target for postoperative breast radiotherapy, and displacement of surgical clips would result in inaccurate delivery of radiation. We investigated the displacement range of surgical clips in the breast during postoperative radiotherapy following breast-conserving surgery.

METHODS

A total of 178 patients who received breast-conserving surgery and postoperative radiation of 59.4 Gy in 33 fractions to the involved breast for 6.5 weeks were included. Surgical clips were used to mark the lumpectomy cavity during breast-conserving surgery. Patients undertook planning computed tomography (CT) scan for whole breast irradiation. Five weeks after beginning radiation, when the irradiation dose was 45 Gy, planning CT scan was performed again for a boost radiotherapy plan in all patients. The surgical clips were defined in both CT images and compared in lateromedial (X), anteroposterior (Y), superoinferior (Z), and three-dimensional directions.

RESULTS

The 90th percentile of displacement of surgical clips was 5.31 mm (range, 0.0-22.2 mm) in the lateromedial direction, 7.1 mm (range, 0.0-14.2 mm) in the anteroposterior direction, and 6.0 mm (range, 0.0-10.0 mm) in the superoinferior direction. The 90th percentile of three-dimensional displacement distance was 9.8 mm (range, 0.0-28.2 mm). On the multivariate analysis, seroma ≥15 mL was the only independent factor associated with the displacement of surgical clips. In patients with seroma ≥15 mL, the 90th percentile of displacement of surgical clips was 15.1 mm in the lateromedial direction, 12.7 mm in the anteroposterior direction, 10.0 mm in the superoinferior direction, and 21.8 mm in the three-dimensional distance.

CONCLUSION

A target volume expansion of 10 mm from surgical clips may be sufficient to compensate for the displacement of clips during postoperative radiotherapy after breast-conserving surgery. For patients who had a seroma, a replanning CT scan for a boost radiation should be considered to ensure exact postoperative radiotherapy in breast cancer.

Accelerated whole breast irradiation in early breast cancer patients with adverse prognostic features

Purpose

Accelerated whole breast irradiation (AWBI) and conventional whole breast irradiation (CWBI) were compared to determine whether AWBI is as effective as CWBI in patients with early breast cancer and adverse prognostic features.

Patients and methods

We included 330 patients who underwent breast-conserving surgery (BCS) and post-operative radiation therapy (RT) using AWBI for pT1-2 and pN0-1a breast cancer from 2007 to 2010. These patients were matched with 330 patients who received CWBI according to stage, age (±3 years), and the year of BCS. AWBI of 39 Gy and CWBI of 50.4 Gy were given in 13 and 28 fractions, respectively.

Results

Median follow-up time was 81.9 months. There were no statistically significant differences between the AWBI and CWBI groups in terms of age, stage, tumor grade, or molecular subtype. More patients with Ki-67 index ≥ 14% were present in the AWBI group (AWBI 47.0% vs. CWBI 10.3%; P<0.01). The 5-year ipsilateral breast tumor relapse (IBTR) rates for the AWBI and CWBI groups were 0.8% and 1.8%, respectively (P=0.54). High tumor grade was a statistically significant risk factor for IBTR (5-year IBTR rate: 2.9%; P=0.01). Ki-67 ≥ 14% was marginally related to IBTR (5-year IBTR rate: 2.2%; P=0.07). There were no statistically significant differences in the hazard ratios between the AWBI and CWBI groups according to any of the risk factors. There were no acute grade 3 toxicities in the AWBI group. There were no late grade 3 toxicities in either group.

Conclusions

AWBI is comparable to CWBI in early breast cancer with adverse prognostic features.