Targeted intraoperative radiotherapy (TARGIT) yields very low recurrence rates when given as a boost

Full-Dose Intraoperative Electron Radiotherapy for Early Breast Cancer: Evidence from a Single Center's Experience

To evaluate the clinical response rate and cosmetic outcome after full-dose intraoperative electron radiotherapy (IOERT) in early breast cancer (BC) treated with conserving surgery. Inclusion criteria were: >60 years old, clinical tumor size ≤2 cm, luminal A carcinoma, patological negative lymph nodes, excluded lobular carcinoma histology. IOERT was delivered with a dose of 21 Gy at 90% isodose. Clinical, cosmetic and/or instrumental follow-up were performed 45 days after IOERT, 6 months after the first check, and every 12 months thereafter. Acute and late toxicities were assessed with the CTCAE v.4.03 and EORTC-RTOG scales, respectively. Cosmetic outcome was evaluated using the Harvard/NSABO/RTOG Breast Cosmesis Grading Scale. Overall, 162 consecutive patients were included in this analysis (median follow-up: 54 months, range: 1-98 months). The overall response rate was 97.5% (CI 95%: 0.93-0.99%). Locoragional relapse occurred in 2.5% of patients. No patient showed distant metastases. No patient showed radiation-related acute complications, with 3.7% showing late G2-3 toxicity. Only 3.7% of patients showed poor cosmetic results. Our data confirmed that IOERT is a feasible and valid therapeutic option in low-risk BC patients treated with lumpectomy. A low local recurrence rate combined with good cosmetic results validates the settings of our operative method in routinely clinical practice.

High-dose Irradiation Stimulated Breast Tumor Microenvironment to Enhance Tumor Cell Growth and Decrease Tumor Cell Motility

Background

Surgery and radiotherapy are two main modalities of breast cancer treatment. However, surgery affects the tumor microenvironment negatively and promotes the growth of possible malignant cells remaining in the tumor bed.

Objective

The present study aimed to investigate the effects of intraoperative radiotherapy (IORT) on the tumor microenvironment. Therefore, the effect of surgical wound fluid (WF), collected from operated and irradiated patients on the growth and motility of a breast cancer cell line (MCF-7) was assessed.

Material and Methods

In this experimental study, preoperative blood serum (PS) and secreted WF from 18 patients who underwent breast-conserving surgery (IORT-) and 19 patients who received IORT following surgery (IORT+) were collected. The samples were purified and added to MCF-7 cultures. Two groups of the cells were treated with and without fetal bovine serum (FBS) and used as positive and negative controls. Applying 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and scratch wound healing assays, the growth and motility of MCF-7 cells were measured.

Results

Cell growth of the cells receiving WF from IORT+ patients (WF+) was statistically higher than the corresponding values of the cells received PS or WF from IORT- patients (WF-) (P<0.01). Both WF+ and WF- decreased the cells' migration ability compared to PS (P<0.02) and FBS (P<0.002), although WF+ caused a more significant reduction (P<0.02).

Conclusion

Wound fluid extracted from breast cancer patients who underwent both surgery and IORT increased the growth of breast tumor cells, but decreased their ability to migrate.

Deep inspiration breath-hold radiation therapy in left-sided breast cancer patients: a single-institution retrospective dosimetric analysis of organs at risk doses

BACKGROUND

Radiotherapy can induce cardiac injury in left-sided breast cancer cases. Cardiac-sparing irradiation using the deep inspiration breath-hold (DIBH) technique can achieve substantial dose reduction to vulnerable cardiac substructures compared with free breathing (FB). This study evaluated the dosimetric differences between both techniques at a single institution.

METHODS

From 2017 to 2019, 130 patients with left-sided breast cancer underwent breast-conserving surgery (BCS; n = 121, 93.1%) or mastectomy (ME; n = 9, 6.9%) along with axillary lymph node staging (n = 105, 80.8%), followed by adjuvant irradiation in DIBH technique; adjuvant systemic therapy was included if applicable. 106 (81.5%) patients received conventional and 24 (18.5%) hypofractionated irradiation. Additionally, 12 patients received regional nodal irradiation. Computed tomography (CT) scans in FB and DIBH position were performed for all patients. Intrafractional 3D position monitoring of the patient surface in deep inspiration and breath gating was performed using Sentinel and Catalyst HD 3D surface scanning systems (C-RAD, Catalyst, C‑RAD AB, Uppsala, Sweden). Individual coaching and determination of breathing amplitude during the radiation planning CT was performed. Three-dimensional treatment planning was performed using standard tangential treatment portals (6 or 18 MV). The delineation of cardiac structures and both lungs was done in both the FB and the DIBH scan.

RESULTS

All dosimetric parameters for cardiac structures were significantly reduced (p < 0.01 for all). The mean heart dose (Dmean) in the DIBH group was 1.3 Gy (range 0.5-3.6) vs. 2.2 Gy (range 0.9-8.8) in the FB group (p < 0.001). The Dmean for the left ventricle (LV) in DIBH was 1.5 Gy (range 0.6-4.5), as compared to 2.8 Gy (1.1-9.5) with FB (p < 0.001). The parameters for LV (V10 Gy, V15 Gy, V20 Gy, V23 Gy, V25 Gy, V30 Gy) were reduced by about 100% (p < 0.001). The LAD Dmean in the DIBH group was 4.1 Gy (range 1.2-33.3) and 14.3 Gy (range 2.4-37.5) in the FB group (p < 0.001). The median values for LAD such as V15 Gy, V20 Gy, V25 Gy, V30 Gy, and V40 Gy decreased by roughly 100% (p < 0.001). An increasing volume of left lung in the DIBH position resulted in dose sparing of cardiac structures.

CONCLUSION

For all ascertained dosimetric parameters, a significant dose reduction could be achieved in DIBH technique.

Hypofractionated Whole Breast Irradiation and Boost-IOERT in Early Stage Breast Cancer (HIOB): First Clinical Results of a Prospective Multicenter Trial (NCT01343459)

Background and purpose: To investigate intraoperative electron radiation therapy (IOERT) as a tumor bed boost during breast conserving surgery (BCS) followed by hypofractionated whole breast irradiation (HWBI) on age-correlated in-breast recurrence (IBR) rates in patients with low- to high-risk invasive breast cancer. Material and methods: BCS and IOERT (11.1 Gy) preceded a HWBI (40.5 Gy) in 15 fractions. Five-year IBR-rates were compared by a sequential ratio test (SQRT) with best evidences in three age groups (35−40 y and 41−50 y: 3.6%, >50 y: 2%) in a prospective single arm design. Null hypothesis (H0) was defined to undershoot these benchmarks for proof of superiority. Results: Of 1445 enrolled patients, 326 met exclusion criteria, leaving 1119 as eligible for analysis. After a median follow-up of 50 months (range 0.7−104), we detected two local recurrences, both in the age group >50 y. With no observed IBR, superiority was demonstrated for the patient groups 41−50 and >50 y, respectively. For the youngest group (35−40 y), no appropriate statistical evaluation was yet possible due to insufficient recruitment. Conclusions: In terms of five-year IBR-rates, Boost-IOERT followed by HWBI has been demonstrated to be superior in patients older than 50 and in the age group 41−50 when compared to best published evidence until 2010.

Safety and efficacy of INTRABEAM intraoperative radiotherapy for invasive thymoma

Intraoperative radiotherapy (IORT) has been used to treat different residual solid tumors after tumor removal and has shown many advantages over other treatment methods. However, the use of IORT for invasive thymoma has not been reported. Therefore, in this study, we tried to determine the safety and efficacy of INTRABEAM IORT for the treatment of invasive thymoma.Among the patients admitted to our hospital from September to December 2016 who were diagnosed with invasive thymoma, 14 were selected as study subjects. With medical histories taken beforehand, 8 of these patients were diagnosed with Masaoka stage IIA and 6 with Masaoka stage IIB; furthermore, 5 of the patients were diagnosed with myasthenia gravis (MG). INTRABEAM radiation (8-10 Gy, low energy) was delivered to the postoperative tumor bed of each patient during surgery. The intra- and postoperative complications were observed and evaluated, and the improvement in symptoms was assessed. An additional 23 patients with stage II thymoma undergoing radical surgery from April to August 2016 were chosen as the control group.One month after the operation, only 1 patient in the IORT group had cough, increased levels of leucocytes and neutrophils, and pulmonary inflammation on chest computed tomography. Reactive inflammation and pleural effusion in the 2 groups were similar (P > .05). There was no significant difference between the 2 groups in the improvement of myasthenia gravis (P > .05). Postoperative chest computed tomography and routine blood examination at 3 and 12 months showed that all the patients recovered, with normal hemogram levels and no pulmonary fibrosis around the radiation field. In addition, ultrasonic cardiography and electrocardiography demonstrated no significant difference before or after surgery within the IORT group. At the end of the follow-up, all the patients were alive, no relapse or remote metastasis was observed in the IORT group, and 2 inpatients in the control group had experienced relapse at 24 and 26 months. There was a significant difference in disease-free survival between the 2 groups (P = .00).It is safe to administer low-energy INTRABEAM IORT at a dose of approximately 10 Gy in patients with stage II invasive thymoma. INTRABEAM IORT does not significantly increase operation- or radiation-related complications and has no significant effect on vital organs such as the lungs and heart. Its long-term efficacy is worth expecting.

Long-term outcome after intraoperative radiotherapy as a boost in breast cancer

PURPOSE

To investigate long-term oncological outcome and incidence of chronic side effects in patients with breast cancer and intraoperative radiotherapy given as an upfront boost (IORT boost).

METHODS

Retrospective analysis of 400 patients with an IORT boost with low-energy X‑rays (20 Gy), subsequent whole-breast irradiation (46-50 Gy), and annual oncological follow-up. Side effects were prospectively evaluated (LENT-SOMA scales) over a period of up to 15 years. Side effects scored ≥grade 2 at least three times during follow-up were judged to be chronic.

RESULTS

The median age was 63 years (30-85) and the median follow-up was 78 months (2-180) after IORT boost. In 15 patients a local recurrence occurred, resulting in a local recurrence rate at 5, 10, and 15 years of 2.0%, 6.6%, and 10.1%, respectively. The overall survival rates at 5, 10, and 15 years were 92.1%, 81.8%, and 80.7%, respectively. The most common high-grade side effects were fibrosis (21%) and pain (8.6%). The majority of side effects occurred within the first 3 years. The actuarial rates of chronic fibrosis were 19.1% and 21.1% at 5 and ≥8 years, of chronic pain 8.6% at ≥4 years, of chronic edema of the breast 2.4% at ≥2 years, of chronic lymphedema 0.0% at 5 and 10 years, and of chronic hyperpigmentation 0.5% at ≥2 years. Side effects were similar or less than expected from an external beam boost.

CONCLUSION

IORT boost appears to be a highly efficient and safe method for upfront delivery of the tumor bed boost in high-risk breast cancer patients.

Surgical wound fluids from patients treated with intraoperative radiotherapy induce radiobiological response in breast cancer cells

Breast cancer is the most common cancer occurring in women. The standard of breast cancer treatment is based on breast-conserving surgery with administration of adjuvant whole breast radiotherapy. Research shows that in-breast relapse is most likely to occur in the tumour bed, i.e. around the scar. Intraoperative radiotherapy (IORT), in which radiation is delivered to the tumour bed, reduces the risk of local recurrence not only through direct cell killing, but also through modification of local microenvironment. Additionally IORT modifies the composition and biological activity of surgical wound fluid. Since many researchers show that radiation damage is mediated through factors secreted to the environment by irradiated cells, we hypothesized that this radiation-induced bystander effect is partly responsible for the change observed in surgical wound fluids. We collected conditioned medium from irradiated breast cancer cells (CM) and surgical wound fluids from patients who underwent IORT (RT-WF) and from patients after breast-conserving surgery alone (WF). We incubated two breast cancer cell lines (MCF-7 and MDA-MB-468) with WF, RT-WF, CM or WF + CM and measured radiobiological response of cells. We measured the level of double-strand breaks, induction of apoptosis and the changes in expression of genes related to DNA damage repair. We observed that stimulation with RT-WF and with WF + CM-induced double-strand breaks and increased expression of DNA damage repair-related genes, which was not observed after stimulation with WF. These results suggest that IOERT induces secretion of bystander factors mediating the genotoxic effect of ionizing radiation.

Frequency of whole breast irradiation (WBRT) after intraoperative radiotherapy (IORT) is strongly influenced by institutional protocol qualification criteria

Background

Accelerated partial breast irradiation (APBI) is a promising method of adjuvant radiotherapy for select patients. Intraoperative radiotherapy (IORT) is a form of APBI, and appropriate patient selection is important.

Aim

The aim of our study was to analyse the influence of our protocol on the frequency of WBRT after IORT and our protocol's correlation with the reported use of WBRT according to TARGIT guidelines. We also aimed to verify how changes in our protocol influenced the frequency of WBRT.

Material and methods

Between April 20, 2010 and May 10, 2017, we identified 207 patients irradiated with IORT for APBI.

Results

Ninety-one patients (44%) met the criteria for APBI only, while 116 (56%) should have been offered additional WBRT. Retrospective analysis showed that WBRT was applied statistically significantly less frequently compared with strict protocol indications: 99 patients (47.8%) received APBI only and 108 (51.2%) underwent adjuvant WBRT (p < 0.0001). Applying the TARGIT trial guidelines, 69 patients (33.4%) should have been offered WBRT (p < 0.0001), which is twice the number of patients treated with WBRT in our study. Changing the protocol to less restrictive criteria would have statistically significantly decreased the number of patients (95, 46%) offered WBRT (p < 0.0001).

Conclusions

Following international guidelines, 46% of patients should receive WBRT after IORT, which is 1.5-2 times more than for the TARGIT criteria. In our analysis, a high percentage of patients (19%) did not receive WBRT after IORT despite the protocol recommendations. The chosen protocol strongly influences the frequency of adjuvant WBRT.

Intraoperative radiotherapy: review of techniques and results

Intraoperative radiotherapy (IORT) is a technique that involves precise delivery of a large dose of ionising radiation to the tumour or tumour bed during surgery. Direct visualisation of the tumour bed and ability to space out the normal tissues from the tumour bed allows maximisation of the dose to the tumour while minimising the dose to normal tissues. This results in an improved therapeutic ratio with IORT. Although it was introduced in the 1960s, it has seen a resurgence of popularity with the introduction of self-shielding mobile linear accelerators and low-kV IORT devices, which by eliminating the logistical issues of transport of the patient during surgery for radiotherapy or building a shielded operating room, has enabled its wider use in the community.

Electrons, low-kV X-rays and HDR brachytherapy are all different methods of IORT in current clinical use. Each method has its own unique set of advantages and disadvantages, its own set of indications where one may be better suited than the other, and each requires a specific kind of expertise.

IORT has demonstrated its efficacy in a wide variety of intra-abdominal tumours, recurrent colorectal cancers, recurrent gynaecological cancers, and soft-tissue tumours. Recently, it has emerged as an attractive treatment option for selected, early-stage breast cancer, owing to the ability to complete the entire course of radiotherapy during surgery. IORT has been used in a multitude of roles across these sites, for dose escalation (retroperitoneal sarcoma), EBRT dose de-escalation (paediatric tumours), as sole radiation modality (early breast cancers) and as a re-irradiation modality (recurrent rectal and gynaecological cancers).

This article aims to provide a review of the rationale, techniques, and outcomes for IORT across different sites relevant to current clinical practice.

Breastdosimetry of 99mTc-balloon in complementary radiotherapy

Dose reinforcement in primary tumor cavity can complement conventional radiotherapy in patients with early breast cancer. In this study, a dosimetric analysis was conducted by pertechnetate-^99mTc-filled balloon brachytherapy (TBB).

METHODS

Dosimetry based on radiochromic films and on a computational voxel thorax model was performed. Calibration protocol achieved a mathematical relationship between dose and optical density in films placed on the surface at a distance of 0-9cm, 1cm between them, in which dose values were provided by MCNP® code. Moreover, experimental spatial dose distribution was prepared. A female thorax voxel model was developed in the SISCODES®/MCNP® codes. Additionally, experimental and computational doses at 8-10mm from balloon surface were compared.

RESULTS

Dose from ^99mTc-balloon, with 16mm diameter, 32.22GBq activity, and 24h exposure time, achieved 8.08±0.42 (Ue) and 8.82±1.76 (Ue) Gy, at a distance of 10mm from the balloon surface for the experimental data and computational modeling, respectively, thus showing nonsignificant difference. The spatial dose distribution in the chest wall, glandular tissue, breast skin, and lung was presented. The dosimetric findings supported the TBB modality presenting a suitable spatial dose distribution in the tumor bed and preserving the adjacent health tissues.

CONCLUSION

TBB is a viable adjuvant brachytherapy modality for breast cancer in patients who have an appropriate indication.

An international randomised controlled trial to compare TARGeted Intraoperative radioTherapy (TARGIT) with conventional postoperative radiotherapy after breast-conserving surgery for women with early-stage breast cancer (the TARGIT-A trial)

BACKGROUND

Based on our laboratory work and clinical trials we hypothesised that radiotherapy after lumpectomy for breast cancer could be restricted to the tumour bed. In collaboration with the industry we developed a new radiotherapy device and a new surgical operation for delivering single-dose radiation to the tumour bed - the tissues at highest risk of local recurrence. We named it TARGeted Intraoperative radioTherapy (TARGIT). From 1998 we confirmed its feasibility and safety in pilot studies.

OBJECTIVE

To compare TARGIT within a risk-adapted approach with whole-breast external beam radiotherapy (EBRT) over several weeks.

DESIGN

The TARGeted Intraoperative radioTherapy Alone (TARGIT-A) trial was a pragmatic, prospective, international, multicentre, non-inferiority, non-blinded, randomised (1 : 1 ratio) clinical trial. Originally, randomisation occurred before initial lumpectomy (prepathology) and, if allocated TARGIT, the patient received it during the lumpectomy. Subsequently, the postpathology stratum was added in which randomisation occurred after initial lumpectomy, allowing potentially easier logistics and a more stringent case selection, but which needed a reoperation to reopen the wound to give TARGIT as a delayed procedure. The risk-adapted approach meant that, in the experimental arm, if pre-specified unsuspected adverse factors were found postoperatively after receiving TARGIT, EBRT was recommended. Pragmatically, this reflected how TARGIT would be practised in the real world.

SETTING

Thirty-three centres in 11 countries.

PARTICIPANTS

Women who were aged ≥ 45 years with unifocal invasive ductal carcinoma preferably ≤ 3.5 cm in size.

INTERVENTIONS

TARGIT within a risk-adapted approach and whole-breast EBRT.

MAIN OUTCOME MEASURES

The primary outcome measure was absolute difference in local recurrence, with a non-inferiority margin of 2.5%. Secondary outcome measures included toxicity and breast cancer-specific and non-breast-cancer mortality.

RESULTS

In total, 3451 patients were recruited between March 2000 and June 2012. The following values are 5-year Kaplan-Meier rates for TARGIT compared with EBRT. There was no statistically significant difference in local recurrence between TARGIT and EBRT. TARGIT was non-inferior to EBRT overall [TARGIT 3.3%, 95% confidence interval (CI) 2.1% to 5.1% vs. EBRT 1.3%, 95% CI 0.7% to 2.5%; p = 0.04; P_{non-inferiority} = 0.00000012] and in the prepathology stratum (n = 2298) when TARGIT was given concurrently with lumpectomy (TARGIT 2.1%, 95% CI 1.1% to 4.2% vs. EBRT 1.1%, 95% CI 0.5% to 2.5%; p = 0.31; P_{non-inferiority} = 0.0000000013). With delayed TARGIT postpathology (n = 1153), the between-group difference was larger than 2.5% and non-inferiority was not established for this stratum (TARGIT 5.4%, 95% CI 3.0% to 9.7% vs. EBRT 1.7%, 95% CI 0.6% to 4.9%; p = 0.069; P_{non-inferiority} = 0.06640]. The local recurrence-free survival was 93.9% (95% CI 90.9% to 95.9%) when TARGIT was given with lumpectomy compared with 92.5% (95% CI 89.7% to 94.6%) for EBRT (p = 0.35). In a planned subgroup analysis, progesterone receptor (PgR) status was found to be the only predictor of outcome: hormone-responsive patients (PgR positive) had similar 5-year local recurrence with TARGIT during lumpectomy (1.4%, 95% CI 0.5% to 3.9%) as with EBRT (1.2%, 95% CI 0.5% to 2.9%; p = 0.77). Grade 3 or 4 radiotherapy toxicity was significantly reduced with TARGIT. Overall, breast cancer mortality was much the same between groups (TARGIT 2.6%, 95% CI 1.5% to 4.3% vs. EBRT 1.9%, 95% CI 1.1% to 3.2%; p = 0.56) but there were significantly fewer non-breast-cancer deaths with TARGIT (1.4%, 95% CI 0.8% to 2.5% vs. 3.5%, 95% CI 2.3% to 5.2%; p = 0.0086), attributable to fewer deaths from cardiovascular causes and other cancers, leading to a trend in reduced overall mortality in the TARGIT arm (3.9%, 95% CI 2.7% to 5.8% vs. 5.3%, 95% CI 3.9% to 7.3%; p = 0.099]. Health economic analyses suggest that TARGIT was statistically significantly less costly than EBRT, produced similar quality-adjusted life-years, had a positive incremental net monetary benefit that was borderline statistically significantly different from zero and had a probability of > 90% of being cost-effective. There appears to be little uncertainty in the point estimates, based on deterministic and probabilistic sensitivity analyses. If TARGIT were given instead of EBRT in suitable patients, it might potentially reduce costs to the health-care providers in the UK by £8-9.1 million each year. This does not include environmental, patient and societal costs.

LIMITATIONS

The number of local recurrences is small but the number of events for local recurrence-free survival is not as small (TARGIT 57 vs. EBRT 59); occurrence of so few events (< 3.5%) also implies that both treatments are effective and any difference is unlikely to be large. Not all 3451 patients were followed up for 5 years; however, more than the number of patients required to answer the main trial question (n = 585) were followed up for > 5 years.

CONCLUSIONS

For patients with breast cancer (women who are aged ≥ 45 years with hormone-sensitive invasive ductal carcinoma that is up to 3.5 cm in size), TARGIT concurrent with lumpectomy within a risk-adapted approach is as effective as, safer than and less expensive than postoperative EBRT.

FUTURE WORK

The analyses will be repeated with longer follow-up. Although this may not change the primary result, the larger number of events may confirm the effect on overall mortality and allow more detailed subgroup analyses. The TARGeted Intraoperative radioTherapy Boost (TARGIT-B) trial is testing whether or not a tumour bed boost given intraoperatively (TARGIT) boost is superior to a tumour bed boost given as part of postoperative EBRT.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN34086741 and ClinicalTrials.gov NCT00983684.

FUNDING

University College London Hospitals (UCLH)/University College London (UCL) Comprehensive Biomedical Research Centre, UCLH Charities, Ninewells Cancer Campaign, National Health and Medical Research Council and German Federal Ministry of Education and Research (BMBF). From September 2009 this project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 20, No. 73. See the NIHR Journals Library website for further project information.

Risk factors for seroma evacuation in breast cancer patients treated with intraoperative radiotherapy

BACKGROUND

Novel techniques in oncology provide new treatment opportunities but also introduce different patterns of side effects. Intraoperative radiotherapy (IORT) allows a shortened overall treatment time for early breast cancer either combined with whole breast radiotherapy (WBRT), or alone. Although the early side effects of IORT are well known, data on clinically important late side effects, which require medical intervention, are scarce.

AIM

In this study, we analyze risk factors for seroma evacuation more than 6 months after IORT.

MATERIALS AND METHODS

We evaluated 120 patients with a mean follow-up of 27.8 months (range: 7-52 months). Fifty-one patients received IORT only and 69 were additionally treated with WBRT.

RESULTS

Seroma evacuation was performed 6-38 months after IORT. Two (3.9%) events were observed in the IORT group and 14 (20%) in the IORT + WBRT group. Univariate (Kaplan-Meier) analysis showed that addition of WBRT to IORT increased the risk of seroma evacuation [hazard ratio = 5.5, 95% confidence interval: 2.0-14.7, P = 0.011]. In a multivariate analysis (Cox proportional hazards regression), WBRT and axillary lymph node dissection were significant risk factors for seroma evacuation (model P value = 0.0025).

CONCLUSIONS

WBRT applied after IORT is associated with increased risk of seroma evacuation, which might be considered as a late side effect.

[Operative therapy of spinal metastases from urological tumors]

The treatment of bone metastases from urological tumors represents a palliative form of therapy, apart from the resection of solitary metastases from renal cell carcinomas. Due to the high incidence of spinal metastases this can result in clinically significant symptoms and possible complications for patients, such as pain, spinal instability and compression of the spinal canal with corresponding neurological deficits. By the use of targeted diagnostics and induction of radiotherapeutic and/or surgical treatment, for the majority of patients an immediate reduction in pain as well as early mobilization and sometimes even regression of existing neurological deficits and therefore an improved quality of life can be achieved.

Accelerated Partial Breast Irradiation in Clinical Practice

Accelerated partial breast irradiation (APBI) has been under clinical investigation for more than 15 years. There are several technical approaches that are clinically established, e.g. brachytherapy, intraoperative radiotherapy (IORT), or external-beam radiotherapy. The understanding of the underlying biology, optimal technical procedures, patient selection criteria, and imaging changes during follow-up has increased enormously. After completion of several phase III trials using brachytherapy or IORT, APBI is currently increasingly used either in phase IV studies, registries, or in selected patients outside of clinical studies. Consensus statements about suitable patients are available from several international and national societies like ASTRO, ESTRO, and DEGRO. One may expect that 15-25% of patients undergoing breast-conserving surgery may qualify for APBI, i.e. patients with small invasive ductal breast cancer without clinical lymph node involvement.

Intraoperative radiotherapy in early stage breast cancer: potential indications and evidence to date

Following early results of recent studies of intraoperative radiotherapy (IORT) in the adjuvant treatment of patients with early breast cancer, the clinical utility of IORT is a subject of much recent debate within the breast oncology community. This review describes the intraoperative techniques available, the potential indications and the evidence to date pertaining to local control and toxicity. We also discuss any implications for current practice and future research.

Breast stromal fibroblasts from histologically normal surgical margins are pro-carcinogenic

There is evidence that normal breast stromal fibroblasts (NBFs) suppress tumour growth, while cancer-associated fibroblasts (CAFs) promote tumourigenesis through functional interactions with tumour cells. Little is known about the biology and the carcinogenic potential of stromal fibroblasts present in histologically normal surgical margins (TCFs). Therefore, we first undertook gene expression analysis on five CAF/TCF pairs from breast cancer patients and three NBF samples (derived from mammoplasties). This comparative analysis revealed variation in gene expression between these three categories of cells, with a TCF-specific gene expression profile. This variability was higher in TCFs than in their paired CAFs and also NBFs. Cytokine arrays show that TCFs have a specific secretory cytokine profile. In addition, stromal fibroblasts from surgical margins expressed high levels of α-SMA and SDF-1 and exhibited higher migratory/invasiveness abilities. Indirect co-culture showed that TCF cells enhance the proliferation of non-cancerous mammary epithelial cells and the epithelial-to-mesenchymal transition of breast cancer cells. Moreover, TCF and CAF cells increased the level of PCNA, MMP-2 and the phosphorylated/activated form of Akt in normal breast luminal fibroblasts in a paracrine manner. Furthermore, TCFs were able to promote the formation and growth of humanized orthotopic breast tumours in nude mice. Interestingly, these TCF phenotypes and the extent of their effects were intermediate between those of NBFs and CAFs. Together, these results indicate that stromal fibroblasts located in non-cancerous tissues exhibit a tumour-promoting phenotype, indicating that their presence post-surgery may play important roles in cancer recurrence.

Feasibility of concervative breast surgery and intraoperative radiation therapy for early breast cancer: a single-center, open, non-randomized, prospective pilot study

Intraoperative radiotherapy (IORT) consists of an accelerated, single-dose, partial breast irradiation, performed immediately after breast conservative surgery. In the present study, we report the results of our feasibility protocol study using IORT between 2005 and 2009. We analyzed the data from a single-center, open, non-randomized, prospective pilot study including patients who underwent breast conservative surgery for invasive breast cancer between January 2005 and December 2009 at our Clinic of Surgery. Patients were divided based on IORT performance and stratified by age (≥48 or <48 years). Data were analyzed using R (version 2.15.2), considering a level of significance at P<0.05. Among the 247 eligible patients, 81 accepted the IORT protocol. Intraoperative IORT feasibility was 95.1% (77/81). In 71.4% (55/77) of the cases no postoperative complication was registered. Concerning local recurrence and overall survival, no significant difference was observed between women who underwent the IORT protocol or standard treatment. Among the patients aged <48 years, no local recurrence was noted after IORT protocol, and among women aged ≥48, local recurrences developed later in patients treated with IORT than with standard treatment. IORT represents a feasible and promising technique for the treatment of early breast cancer, with low morbidity, and beneficial aesthetic and oncologic results. Further studies are required in order to extend the inclusion criteria and offer IORT to a larger number of breast cancer patients.

Intraoperative radiotherapy in patients with breast cancer treated by breast-conserving therapy

Objective

To assess the safety, cosmetic effects, and clinical efficacy of breast-conserving surgery combined with intraoperative radiation therapy for the treatment of Chinese patients with breast cancer.

Methods

Breast-conserving surgery combined with intraoperative radiation therapy was performed in 64 breast cancer patients. The postoperative short-term efficacy, safety, and cosmetic effects were assessed.

Results

Of the 64 patients, 1 case (1.6%) had local recurrence one year later, 7 cases (10.9%) had grade I postoperative radiation-induced lung injury, 10 cases (15.6%) had local hardening at the surgical sites, 8 cases (12.5 %) had changes in skin color, and 8 cases (12.5%) had pain at the surgical sites. Excellent or good levels of cosmetic effects were achieved in 95.3% of the patients.

Conclusions

The application of intraoperative radiation therapy with breast-conserving surgery can yield satisfactory short-term curative efficacy, a high level of clinical safety, and good cosmetic effects.

Discrepancies in determining electron energy for lumpectomy boost treatment

The aim of this study was to compare lumpectomy cavity depth measurements obtained through ultrasound (U/S) and retrospective computed tomography (CT). Twenty-five patients with stage T1-2 invasive breast cancer formed the cohort of this study. Their U/S and CT measurements were converted into electron energy and compared. The mean U/S depth was 3.6 ± 1.3 cm, while the mean CT depth was 4.9 ± 1.9 cm; the listed error ranges are one standard deviation. Electron energies for treatment ranged from 6 MeV to 12 MeV based on the U/S determination. There was no significant correlation between cavity depths measured by U/S and CT (R²= 0.459, P < 0.002). Furthermore, only 20% of CT-based electron energy determinations matched the corresponding U/S determinations. This ratio increased to 40% when taking into account an upper limit based on the depth of organs at risk below the cavity. The study shows that there is a significant discrepancy between cavity depths determined by U/S and CT. It also supports the concept that post-lumpectomy radiotherapy boosts should be tailored according to the needs and comfort of individual practices and institutions.

Intraoperative radiotherapy during breast-conserving surgery using a miniature x-ray generator (Intrabeam®): theoretical and experimental background and clinical experience

Breast cancer is currently the most frequent indication for intraoperative radiotherapy with increasing numbers worldwide. Intraoperative radiotherapy can be used as a tumor bed boost followed by whole breast radiotherapy, or as a distinct form of accelerated partial breast irradiation in selected patients. This article summarizes the theoretical background including pattern of recurrence and distribution of tumor cell foci in the breast and discusses the rationale for intraoperative radiotherapy, especially using a miniature x-ray generator (Intrabeam(®)). The concepts of how to avoid geographic and temporal miss by giving radiotherapy during surgery to the open wound cavity are described. Experimental and clinical experience is presented based on in vitro experiments and more than 300 treated patients in a single department with mature follow-up.

Efficacy and safety of intraoperative radiotherapy in breast cancer: a systematic review

The objective of this study is to assess the efficacy and safety of intraoperative radiotherapy (IORT) for early breast cancer through a systematic review. Fifteen studies met the inclusion criteria. Most studies assessed the combined treatment with IORT (10-24Gy) and external beam radiotherapy (EBRT) (45-50Gy) on early stage breast cancer (T(0-2)). Local control was over 95% for 1 and 4years of follow-up and the 5-year overall survival was 99%. The TARGIT-A study found a similar survival comparing IORT with standard treatment. The incidence of acute and chronic complications was scarce. IORT is well tolerated by patients and acute and late toxicities are low. There are no differences in survival for IORT treated patients versus standard treatment.

Local control following single-dose intraoperative radiotherapy prior to surgical excision of early-stage breast cancer

BACKGROUND

Multiple partial breast radiotherapy techniques are available. We have previously presented the technical details of our procedure of delivering partial breast irradiation with a single fraction of intraoperative radiotherapy (IORT) targeting the tumor in situ prior to partial mastectomy. This study details our completed, single-institution trial.

MATERIALS AND METHODS

An IRB-approved, DSMB-monitored phase II trial was performed with the following inclusion criteria: women age ≥48, ultrasound-visible invasive ductal cancers <3 cm, clinically negative axillary nodes. IORT was delivered using mobile electron irradiator, at least a 1.5-cm radial and 1-cm deep margin; patients received 15 Gy and immediately underwent partial mastectomy. Ipsilateral breast recurrence was classified as true/marginal, elsewhere in the breast or nodal basin. Kaplan-Meier methods were used to estimate survival functions and exact 95% confidence intervals are reported.

RESULTS

Between 2003 and 2007, 71 women underwent IORT (median follow-up: 3.5 years). For patients with tumor-involved or close margins, additional therapy was required: 7 patients, total mastectomy; 11, whole breast radiation. Four women experienced invasive ipsilateral breast failures (1 new primary, 3 margin recurrences) for a 3-year local control rate of 49 of 53 (94.8%; 95% confidence interval 92.4% [95% CI] 84.2–98.3%), actuarial three-year in breast recurrence was 8% (95% CI 2–18%), and breast cancer-specific survival was 100%.

CONCLUSIONS

Intraoperative radiotherapy delivered to an in situ tumor is feasible, but our local control rate at 3.5 years is concerning. Possible changes to this technique to improve local control rates include better preoperative imaging (MRI), routine intraoperative ultrasound, and improved IORT delivery (larger cone, increased dose).

Long-term results of targeted intraoperative radiotherapy (Targit) boost during breast-conserving surgery

PURPOSE

We have previously shown that delivering targeted radiotherapy to the tumour bed intraoperatively is feasible and desirable. In this study, we report on the feasibility, safety, and long-term efficacy of TARGeted Intraoperative radioTherapy (Targit), using the Intrabeam system.

METHODS AND MATERIALS

A total of 300 cancers in 299 unselected patients underwent breast-conserving surgery and Targit as a boost to the tumor bed. After lumpectomy, a single dose of 20 Gy was delivered intraoperatively. Postoperative external beam whole-breast radiotherapy excluded the usual boost. We also performed a novel individualized case control (ICC) analysis that computed the expected recurrences for the cohort by estimating the risk of recurrence for each patient using their characteristics and follow-up period.

RESULTS

The treatment was well tolerated. The median follow up was 60.5 months (range, 10-122 months). Eight patients have had ipsilateral recurrence: 5-year Kaplan Meier estimate for ipsilateral recurrence is 1.73% (SE 0.77), which compares well with that seen in the boosted patients in the European Organization for Research and Treatment of Cancer study (4.3%) and the UK STAndardisation of breast RadioTherapy study (2.8%). In a novel ICC analysis of 242 of the patients, we estimated that there should be 11.4 recurrences; in this group, only 6 recurrences were observed.

CONCLUSIONS

Lumpectomy and Targit boost combined with external beam radiotherapy results in a low local recurrence rate in a standard risk patient population. Accurate localization and the immediacy of the treatment that has a favorable effect on tumour microenvironment may contribute to this effect. These long-term data establish the long-term safety and efficacy of the Targit technique and generate the hypothesis that Targit boost might be superior to an external beam boost in its efficacy and justifies a randomized trial.

Health-related quality of life after breast-conserving surgery and intraoperative radiotherapy for breast cancer using low-kilovoltage X-rays

BACKGROUND

Intraoperative radiotherapy (IORT) is currently being evaluated as a novel approach during breast-conserving surgery (BCS). IORT can be used either as a tumor bed boost followed by external-beam radiotherapy (EBRT) or as a single treatment. In a matched-pair study, we assessed quality of life (QoL) in 69 patients with early breast cancer treated with BCS and/or IORT and/or EBRT.

METHODS

Patients were matched for age and time since BCS. IORT was provided with 50 kV x-rays (Intrabeam) delivering 20 Gy at the applicator surface. EBRT (46 to 50 Gy in 2-Gy fractions in the IORT with EBRT group, and 56 Gy in 2-Gy fractions in the EBRT group) was initiated after completion of wound healing and/or chemotherapy. The mailed questionnaires included the European Organization for the Research and Treatment of Cancer QLQ-C30 and BR23, FACT-F, HADS, Body Image Scale, and Rosenberg Self-Esteem Scale. At 18 to 70 months' follow-up (median 47 months), all patients were disease free.

RESULTS

We found only a few differences between the three groups. There was a trend toward more pain (mean ± standard deviation; 42.8 ± 32.9 vs. 27.5 ± 34.7) and reduced QoL (57.6 ± 20.7 vs. 70.3 ± 23.9) after IORT with EBRT compared with EBRT, respectively. IORT patients reported comparable QoL (70.3 ± 23.0), and less breast symptoms and body image concerns compared to EBRT (8.6 ± 12.3 vs. 19.2 ± 23.8, and 1.7 ± 3.3 vs. 3.4 ± 4.4, respectively). IORT alone resulted in significantly fewer breast symptoms (8.6 ± 12.3; P = 0.012) and less pain (23.9 ± 24.5, P = 0.041) compared with IORT with EBRT (26.1 ± 27.6; 42.8 ± 32.9, respectively).

CONCLUSIONS

Patients with early breast cancer after BCS and IORT with or without EBRT present with comparable QoL like patients receiving EBRT without a boost. IORT patients show the lowest rate of breast symptoms.

Single-center long-term follow-up after intraoperative radiotherapy as a boost during breast-conserving surgery using low-kilovoltage x-rays

BACKGROUND

Intraoperative radiotherapy (IORT) during breast-conserving surgery as a boost followed by whole-breast radiotherapy is increasingly used.

METHODS

Between February 2002 and December 2008, a total of 197 patients were treated with IORT as a boost (20 Gy, 50 kV x-rays; Intrabeam System, Carl Zeiss Surgical, Oberkochen, Germany) during breast-conserving surgery, followed by whole-breast radiotherapy (46-50 Gy). Systemic therapy was provided according to the St. Gallen consensus. Patients were recalled every 6-12 months for follow-up. Findings were scored according to the LENT-SOMA scale.

RESULTS

Median age was 61.8 (range 30-84) years, and median follow-up was 37 (range 5-91) months. There were T1, T2, and Tx tumors in 129, 67, and 1 patients, respectively, and N0, N1, N2, and N3 disease in 144, 36, 15, and 2 patients, respectively. Until December 2009, 5 local invasive relapses, 1 local ductal carcinoma-in-situ, 1 axillary relapse, 6 secondary cancers, and 11 distant metastases were seen, resulting in a 5-year disease-free survival of 81.0% and an overall survival of 91.3%. Local relapse-free survival (invasive cancers) at 3 and 5 years was 97.0%. After a follow-up of 5 years (n =58), only 8 patients (13.8%) had chronic skin toxicities, and 2 patients (3.4%) had a marked increase in density (fibrosis III), while 62.0% had no/barely palpable fibrosis 0-I. Other toxicities observed included severe pain (n = 4, 6.9%), retraction (n =17, 29.3%), edema of the breast (n =1, 1.7%), and lymphedema in general (n =2, 3.4%).

CONCLUSIONS

After IORT as a tumor bed boost with low-kilovoltage x-rays followed by whole-breast radiotherapy, low local recurrence and chronic toxicity rates were seen after 5-year follow-up.

Radiobiological comparison of hypofractionated accelerated partial-breast irradiation (APBI) and single-dose intraoperative radiotherapy (IORT) with 50-kV X-rays

BACKGROUND AND PURPOSE

Intraoperative radiotherapy (IORT) of the tumor bed in early breast cancer is presently performed with a single dose of 50-kV X-rays from a miniaturized X-ray machine using spherical applicators. The purpose was to model the biological effect of hypofractionated accelerated partial-breast irradiation (APBI) with ten fractions.

MATERIAL AND METHODS

The relative biologic effectiveness (RBE) was estimated from the linear-quadratic (L-Q) formalism including repair of sublethal damage or assuming a constant RBE = 1.2-1.5. The radial distribution of biological effect was assessed from clinical dose-response curves. In accordance with clinical convention, the dose for APBI was prescribed at 1 cm depth in the tumor bed, whereas for IORT it was prescribed at the applicator surface.

RESULTS

The fraction size was fitted to give the same risk of late normal-tissue reaction (fibrosis) as single-dose IORT with a maximum dose of 20 Gy. The isoeffective fraction size at 1 cm depth varied between 1.01 Gy for RBE estimated from the L-Q model and 1.64 Gy for constant RBE. The applicator size and dose prescription point influenced the radial dose distribution. The "sphere of equivalence" within which the risk for local recurrence is the same for whole-breast radiotherapy was predicted to extend to 11-15 mm distance from the applicator for alpha/beta = 10 Gy and 9-13 mm for alpha/beta = 4 Gy for hypofractionated APBI, representing an increase of the sphere of equivalence by 2.5-6 mm relative to single-dose IORT.

CONCLUSION

An increase of the therapeutic window with hypofractionated APBI relative to single-dose IORT should be feasible.

Targeted intraoperative radiotherapy versus whole breast radiotherapy for breast cancer (TARGIT-A trial): an international, prospective, randomised, non-inferiority phase 3 trial

BACKGROUND

After breast-conserving surgery, 90% of local recurrences occur within the index quadrant despite the presence of multicentric cancers elsewhere in the breast. Thus, restriction of radiation therapy to the tumour bed during surgery might be adequate for selected patients. We compared targeted intraoperative radiotherapy with the conventional policy of whole breast external beam radiotherapy.

METHODS

Having safely piloted the new technique of single-dose targeted intraoperative radiotherapy with Intrabeam, we launched the TARGIT-A trial on March 24, 2000. In this prospective, randomised, non-inferiority trial, women aged 45 years or older with invasive ductal breast carcinoma undergoing breast-conserving surgery were enrolled from 28 centres in nine countries. Patients were randomly assigned in a 1:1 ratio to receive targeted intraoperative radiotherapy or whole breast external beam radiotherapy, with blocks stratified by centre and by timing of delivery of targeted intraoperative radiotherapy. Neither patients nor investigators or their teams were masked to treatment assignment. Postoperative discovery of predefined factors (eg, lobular carcinoma) could trigger addition of external beam radiotherapy to targeted intraoperative radiotherapy (in an expected 15% of patients). The primary outcome was local recurrence in the conserved breast. The predefined non-inferiority margin was an absolute difference of 2.5% in the primary endpoint. All randomised patients were included in the intention-to-treat analysis. This trial is registered with ClinicalTrials.gov, number NCT00983684.

FINDINGS

1113 patients were randomly allocated to targeted intraoperative radiotherapy and 1119 were allocated to external beam radiotherapy. Of 996 patients who received the allocated treatment in the targeted intraoperative radiotherapy group, 854 (86%) received targeted intraoperative radiotherapy only and 142 (14%) received targeted intraoperative radiotherapy plus external beam radiotherapy. 1025 (92%) patients in the external beam radiotherapy group received the allocated treatment. At 4 years, there were six local recurrences in the intraoperative radiotherapy group and five in the external beam radiotherapy group. The Kaplan-Meier estimate of local recurrence in the conserved breast at 4 years was 1.20% (95% CI 0.53-2.71) in the targeted intraoperative radiotherapy and 0.95% (0.39-2.31) in the external beam radiotherapy group (difference between groups 0.25%, -1.04 to 1.54; p=0.41). The frequency of any complications and major toxicity was similar in the two groups (for major toxicity, targeted intraoperative radiotherapy, 37 [3.3%] of 1113 vs external beam radiotherapy, 44 [3.9%] of 1119; p=0.44). Radiotherapy toxicity (Radiation Therapy Oncology Group grade 3) was lower in the targeted intraoperative radiotherapy group (six patients [0.5%]) than in the external beam radiotherapy group (23 patients [2.1%]; p=0.002).

INTERPRETATION

For selected patients with early breast cancer, a single dose of radiotherapy delivered at the time of surgery by use of targeted intraoperative radiotherapy should be considered as an alternative to external beam radiotherapy delivered over several weeks.

FUNDING

University College London Hospitals (UCLH)/UCL Comprehensive Biomedical Research Centre, UCLH Charities, National Institute for Health Research Health Technology Assessment programme, Ninewells Cancer Campaign, National Health and Medical Research Council, and German Federal Ministry of Education and Research (BMBF).

Targeted intraoperative radiotherapy for breast cancer in patients in whom external beam radiation is not possible

PURPOSE

External beam radiation therapy (EBRT) following wide local excision of the primary tumor is the standard treatment in early breast cancer. In some circumstances this procedure is not possible or is contraindicated or difficult. The purpose of this study was to determine the safety and efficacy of targeted intraoperative radiotherapy (TARGIT) when EBRT is not feasible.

METHODS AND MATERIALS

We report our experience with TARGIT in three centers (Australia, Germany, and the United Kingdom) between 1999 and 2008. Patients at these centers received a single radiation dose of 20 Gy to the breast tissue in contact with the applicator (or 6 Gy at 1-cm distance), as they could not be given EBRT and were keen to avoid mastectomy.

RESULTS

Eighty patients were treated with TARGIT. Reasons for using TARGIT were 21 patients had previously received EBRT, and 31 patients had clinical reasons such as systemic lupus erythematosus, motor neuron disease, Parkinson's disease, ankylosing spondylitis, morbid obesity, and cardiovascular or severe respiratory disease. Three of these patients received percutaneous radiotherapy without surgery; 28 patients were included for compelling personal reasons, usually on compassionate grounds. After a median follow-up of 38 months, only two local recurrences were observed, an annual local recurrence rate of 0.75% (95% confidence interval, 0.09%-2.70%).

CONCLUSIONS

While we await the results of the randomized trial (over 2,000 patients have already been recruited), TARGIT is an acceptable option but only in highly selected cases that cannot be recruited in the trial and in whom EBRT is not feasible/possible.

American Society for Therapeutic Radiology and Oncology (ASTRO) Emerging Technology Committee report on electronic brachytherapy

The development of novel technologies for the safe and effective delivery of radiation is critical to advancing the field of radiation oncology. The Emerging Technology Committee of the American Society for Therapeutic Radiology and Oncology appointed a Task Group within its Evaluation Subcommittee to evaluate new electronic brachytherapy methods that are being developed for, or are already in, clinical use. The Task Group evaluated two devices, the Axxent Electronic Brachytherapy System by Xoft, Inc. (Fremont, CA), and the Intrabeam Photon Radiosurgery Device by Carl Zeiss Surgical (Oberkochen, Germany). These devices are designed to deliver electronically generated radiation, and because of their relatively low energy output, they do not fall under existing regulatory scrutiny of radioactive sources that are used for conventional radioisotope brachytherapy. This report provides a descriptive overview of the technologies, current and future projected applications, comparison of competing technologies, potential impact, and potential safety issues. The full Emerging Technology Committee report is available on the American Society for Therapeutic Radiology and Oncology Web site.

Intraoperative radiotherapy as a boost during breast-conserving surgery using low-kilovoltage X-rays: the first 5 years of experience with a novel approach

PURPOSE

Intraoperative radiotherapy (IORT) during breast-conserving surgery (BCS) has been recently introduced using different devices. We report the first 5 years of a single-center experience after introduction of a novel approach to deliver IORT as a tumor bed boost during BCS for breast cancer.

METHODS AND MATERIALS

A total of 155 breast cancers in 154 women (median age, 63 years; range, 30-83 years; T1/T2 = 100/55; N0/N+ = 108/47) were treated between February 2002 and December 2007 at the University Medical Center Mannheim, in whom IORT as tumor bed boost was applied using 50-kV X-rays (20 Gy) followed by 46-50 Gy whole-breast external-beam radiotherapy (EBRT). Chemotherapy, if indicated, was given before EBRT. The median interval between BCS plus IORT and EBRT was 40 days. Median follow-up was 34 months (maximum 80 months, 1 patient lost to follow-up). Overall survival and local relapse-free survival were calculated at 5 years using the Kaplan-Meier method. Seventy-nine patients were evaluated at 3-year follow-up for late toxicity according to the Late Effects in Normal Tissues-Subjective, Objective, Management, and Analytic system.

RESULTS

Ten patients died, 2 had in-breast relapse, and 8 developed distant metastases (5-year overall survival = 87.0%; 5-year local relapse-free survival = 98.5%). Grade 3 fibroses of the tumor bed were detected in 5% of the patients after 3 years. Skin toxicity was mild (telangiectases and hyperpigmentations in approximately 6% each).

CONCLUSIONS

Intraoperative radiotherapy as a tumor bed boost during BCS for breast cancer using low-kilovoltage X-rays followed by EBRT yields low recurrence and toxicity rates.

Accelerated partial breast irradiation: initial experience with the Intrabeam System

Failure after breast conserving surgery (BCS) and total breast irradiation usually occurs at the site of the original tumor. This has caused an increased interest in accelerated partial breast irradiation (APBI), because if radiation is delivered directly to the tumor bed there should be better local control. Patients greater than age 50 with core biopsy confirmed invasive ductal carcinoma were enrolled. They had preoperative ultrasound defining margins of less than 3.5 cm. Intraoperative ultrasound was also performed in an effort to ensure good surgical margins. After excision of the tumor, intraoperative radiotherapy (IORT) with the Intrabeam System was delivered to the tumor bed. The procedure has been performed on 67 patients. Sixty-one patients had it with the original surgery, while 6 had the procedure after re-exploration of the segmental mastectomy site. Because of the final pathology (surgical margins, tumor biology, and nodal status) 4 patients later had total mastectomy and 11 received total breast irradiation. When total breast irradiation is done the IORT serves as the radiation boost. The cosmetic results have been good to excellent, and there have been no serious surgical or radiation complications. To date there have been no local failures. IORT with the Intrabeam System is feasible, user friendly, versatile, with few complications, good cosmetic results, and great patient acceptance. It is practical and excellent for breast IORT in the community setting.

p53 and gamma radiation in the normal breast

PURPOSE

With the increasing use of radiation as adjuvant therapy in breast cancer, the effects of gamma radiation on the remaining normal breast are of increasing importance. The complexities of multiple cellular types within breast tissues and the role of the pleiotropic Tumour Protein 53 (TP53, p53) protein with its downstream transcriptional targets and cellular processes may be central to the effects on residual normal breast tissues.

CONCLUSION

While a detailed understanding of p53 protein-mediated responses in normal breast tissues remains elusive, p53 appears to have a pivotal role in the effects of gamma radiation on normal breast epithelium, but not stromal cells, which may account for the differing clinical effects of gamma radiation in women treated for breast cancer.

Intraoperative radiation therapy in the treatment of early-stage breast cancer utilizing xoft axxent electronic brachytherapy

BACKGROUND

In an effort to overcome the barriers to BCT, alternative methods of delivering radiation therapy have been explored. APBI allows the radiation treatment to be accomplished in one week or less. XB is a form of balloon-based APBI that uses an electronic source generated by a mobile controller unit. Investigators have also explored IORT treatment that delivers a single fraction of radiation in the operating suite at the time of surgery.

METHODS

We report on the first patient treated with XB to deliver IORT.

RESULTS

IORT treatment utilizing XB is feasible and can be accomplished with a total procedure time of approximately 2 hours.

CONCLUSION

Further research on XB and other methods of IORT is needed to establish clinical efficacy and safety for patients with early-stage breast cancer.

Early initiation of external beam radiotherapy (EBRT) may increase the risk of long-term toxicity in patients undergoing intraoperative radiotherapy (IORT) as a boost for breast cancer

BACKGROUND

Intraoperative radiotherapy (IORT) during breast-conserving surgery is increasingly used. We analyzed the influence of the interval between an IORT boost and external beam radiotherapy (EBRT) on late toxicity.

METHODS

Forty-eight patients received 20 Gy IORT (50 kV X-rays (Intrabeam, Carl Zeiss, Oberkochen, Germany) followed by 46-50 Gy EBRT with a median interval of 36 days (14-197). Late toxicity was assessed with the modified LENT SOMA score after a median of 36 months.

RESULTS

Twelve patients developed a higher grade fibrosis ( degrees II-III), three teleangiectases, one a breast edema grade degrees II, six retractions, four hyperpigmentations and five pain ( degrees II-III). The median interval between IORT and EBRT was significantly shorter in these patients (n=18) compared to the 30 patients without higher grade toxicity (29.5 days vs. 39.5 days, p=0.023, Mann-Whitney U-test).

CONCLUSION

Starting EBRT about 5-6 weeks after IORT appears to be associated with a decreased risk of chronic late toxicity compared with a shorter interval. The impact on local recurrence of prolonged gaps between IORT and EBRT is not known.

Targeted intraoperative radiotherapy impairs the stimulation of breast cancer cell proliferation and invasion caused by surgical wounding

PURPOSE

After apparently successful excision of breast cancer, risk of local recurrence remains high mainly in the area surrounding the original tumor, indicating that wound healing processes may be implicated. The proportional reduction of this risk by radiotherapy does not depend on the extent of surgery, suggesting that radiotherapy, in addition to killing tumor cells, may influence the tumor microenvironment.

EXPERIMENTAL DESIGN

We studied how normal and mammary carcinoma cell growth and motility are affected by surgical wound fluids (WF), collected over 24 h following breast-conserving surgery in 45 patients, 20 of whom had received additional TARGeted Intraoperative radioTherapy (TARGIT), immediately after the surgical excision. The proteomic profile of the WF and their effects on the activation of intracellular signal transduction pathways of breast cancer cells were also analyzed.

RESULTS

WF stimulated proliferation, migration, and invasion of breast cancer cell lines. The stimulatory effect was almost completely abrogated when fluids from TARGIT-treated patients were used. These fluids displayed altered expression of several cytokines and failed to properly stimulate the activation of some intracellular signal transduction pathways, when compared with fluids harvested from untreated patients.

CONCLUSIONS

Delivery of TARGIT to the tumor bed alters the molecular composition and biological activity of surgical WF. This novel antitumoral effect could, at least partially, explain the very low recurrence rates found in a large pilot study using TARGIT. It also opens a novel avenue for identifying new molecular targets and testing novel therapeutic agents.

Locally advanced breast cancer in a 15th century painting in Milan

This previously unreported Renaissance painting depicts a young woman with locally advanced breast cancer reaching out towards a healing potion in the church of Santa Maria della Grazia in Milan, that houses Leonardo da Vinci's Last supper. Today's potion may well contain neoadjuvant systemic therapy including trastuzumab that may allow breast conserving surgery and targeted intraoperative radiotherapy.