A cohort analysis to identify eligible patients for intraoperative radiotherapy (IORT) of early breast cancer

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.

Intraoperative radiotherapy (IORT) of early breast cancer with low-energy x-rays in breast-conserving surgery : Prospective identification of pre- and intraoperative factors influencing the feasibility of IORT

PURPOSE

The aim of this study is to identify pre- and intraoperative factors indicating the feasibility of intraoperative radiotherapy (IORT) during breast-conserving surgery (BCS).

MATERIALS AND METHODS

From January 2018 to December 2019, a total of 128 women undergoing BCS due to early breast cancer were included in this prospective observational study, independent of whether IORT was planned or not. Patient and tumor characteristics as well as surgical parameters that could potentially influence the feasibility of IORT were recorded for the entire collective. In addition, a preoperative senological assessment was performed and analyzed to assess the feasibility of IORT. Logistic regression was then used to identify relevant preoperative parameters and to generate a formula predicting the feasibility of IORT.

RESULTS

Of the 128 included women undergoing BCS, 46 were preoperatively rated to be feasible, 20 to be questionably feasible for IORT. Ultimately, IORT was realized in 30 patients. The most frequent reasons for omission of IORT were insufficient tumor-to-skin distance and/or an excessively large tumor cavity. Small clinical tumor size and large tumor-to-skin distance according to preoperative ultrasound were significantly related to accomplishment of IORT.

CONCLUSION

We observed that preoperative ultrasound-based tumor-skin distance is a significant factor in addition to already known parameters to predict feasibility of IORT. Based on our findings we developed a formula to optimize IORT planning which might serve as an additional tool to improve patient selection for IORT in early breast cancer.

Outcomes and complications of intraoperative radiotherapy versus external beam radiotherapy for early breast cancer

BACKGROUND

Intraoperative radiotherapy (IORT) is an alternative for external beam radiotherapy (EBRT) for early stage breast cancer (BC). Herein, we compared outcomes, postoperative and post-radiation complications of IORT and EBRT.

METHODS

We conducted a cohort study to compare complications of IORT and EBRT in patients. A checklist of the complications of IORT and EBRT, was used to assess and post-radiation complications and outcomes.

RESULTS

Overall, 264 women (121 in IORT and 143 in EBRT group) with a mean (SD) age of 55 ± 8.6 years analyzed in this study. The IORT group (quadrantectomy + SLNB + IORT) had more severe post-operative pain compared to the EBRT group (quadrantectomy + SLNB) (OR = 1.929, 95% CI: 1.116-3.332). Other postoperative complications, including edema, erythema, seroma, hematoma, and wound complications were not significantly different between the IORT and EBRT groups. EBRT was associated with higher rates post-radiation complications, including erythema (95.8% vs. 21.5%), skin dryness (30.8% vs. 12.4%), pruritus (26.6% vs. 17.4%), hyperpigmentation (48.3% vs. 9.9%), and telangiectasia (1.4% vs. 0.8%). Multivariate analysis showed that erythema, skin dryness and pruritus, and hyperpigmentation were more severe in the EBRT group, while breast induration was higher in the IORT group (OR = 4.109, 95% CI: 2.242-7.531). Excellent, good, and fair cosmetic outcome was seen in 11.2%, 72%, and 16.8% of the patients in the EBRT group and 29.8%, 63.6%, and 6.6% in the IORT group, respectively, suggesting that the cosmetic outcome was significantly better in the IORT group (P < .001). There wasn't statistically significant difference in recurrence-free survival and overall survival rates between two groups of patients who received either IORT or EBRT (P = .953, P = .56).

CONCLUSION

IORT is considered to have lower post-radiation complications and better cosmetic outcomes in breast cancer patients. Therefore, IORT might be used as the treatment of choice in eligible patients.

Intraoperative Radiation Therapy: A Large Integrated Health Care System's Approach and Outcomes

Introduction Intraoperative radiation therapy (IORT) may not be as effective in the community compared with clinical trials. Methods The authors reviewed data from the electronic health records of patients who received IORT between February 2014 and February 2020 at a single center within a large integrated health care system. The primary outcome was ipsilateral breast tumor recurrence. Results Of 5731 potentially eligible patients, 245 (4.3%) underwent IORT (mean age: 65.4 ± 0.4 years; median follow-up time: 3.5 years ± 2.2 months). According to the American Society for Radiation Oncology's accelerated partial breast irradiation guidelines based on final pathology, 51% of patients were suitable candidates for IORT, 38.4% were cautionary, and 10.6% were unsuitable. For adjuvant therapy, 6.5% had consolidative whole breast irradiation, and 66.4% received endocrine treatment. At the median follow-up time of 3.5 years, overall ipsilateral breast tumor recurrence was 3.7%. Recurrences tended to be more frequent in patients who refused or did not complete endocrine treatment than in those who received it (7.4% vs 1.9%, p = 0.07). The complication rate was 14.7%, with seroma being the most common (8.2%). Discussion The IORT ipsilateral breast tumor recurrence rate of 3.7% confirms a higher-than-expected rate compared to randomized clinical trials, possibly due to less compliance with endocrine therapy. Conclusion The authors subsequently revised their IORT protocol to require endocrine treatment as a part of the IORT treatment plan and to strongly recommend adjuvant whole breast irradiation for all patients deemed cautionary or unsuitable for IORT according to the American Society for Radiation Oncology's accelerated partial breast irradiation guidelines.

Long-Term Outcomes of an International Cooperative Study of Intraoperative Radiotherapy Upfront Boost With Low Energy X-Rays in Breast Cancer

Purpose

The purpose of this study was to assess the effectivity of upfront kilovoltage intraoperative radiotherapy (IORT) as a boost in high-risk early-stage breast cancer patients from an international pooled cohort.

Materials/Methods

Patients from four centers in three different countries were retrospectively screened. Those with a minimum 1-year follow-up were included. Cumulative local (LR), regional (RR), and distant metastasis rates (DM) were analyzed. Additionally, the estimated overall survival (OS) was assessed. The Cox regression analysis was performed to identify failure predicting factors.

Results

A total of 653 patients from centers in Peru, Spain, and Germany were included. The median follow-up was 55 (12-180) months, and age was 58 (27-86) years. Clinical tumor (T) staging was T1 65.85%, T2 30.17%, and T3 3.98%. Positive margins were found in 7.9% and in-situ component in 20.06%. The median IORT dose was 20 (6-20). The median time from IORT to EBRT was 74.5 (13-364) days. An overall 3.4% (n = 22) of patients developed local recurrence at some point during follow-up. The 12-, 60-, and 120-month cumulative LR were 0.3%, 2.3%, and 7.9%, respectively. After multivariate analysis, only age <50 remained to be a significant prognostic factor for local recurrence (HR 0.19, 95% CI 0.08-0.47; p < 0.05). The 10-year estimated OS was 81.2%.

Conclusion

Upfront boost with IORT yields similar local control outcomes to those EBRT-based reports. Results from prospective trials, regarding toxicity, cosmesis, and effectivity are awaited to confirm these findings.

Patients Older 65 Years With Early Breast Cancer Prefer Intraoperative Radiation as a Locoregional Treatment Choice

BACKGROUND

Patients 65 years old or older with early endocrine-responsive breast cancer have many treatment options, including no radiation. This study aimed to evaluate treatment preference when intraoperative radiation therapy (IORT) is offered in this population.

METHODS

The study reviewed patients 65 years old or older with a diagnosis of early-stage endocrine-responsive breast cancer in 2016-2019 at a single hospital in a large integrated health care system. Electronic medical records of multidisciplinary breast tumor board discussion, treatment options documented by the treatment team, and final treatment offered were reviewed. Variables including age at biopsy, language, endocrine treatment, and comorbidities were collected. Regression analysis was used to evaluate for variables associated with patients' choice regarding radiation treatment.

RESULTS

The institutional IORT guidelines were met by 63 patients in the described age group who had a documented offer of all radiation treatment options. The median age of the patients was 70 years (interquartile range 63-77 years). Overall, 74.6% of the patients chose IORT, and 14.3% opted for whole-breast irradiation. Only 4.8% chose to omit radiation after breast-conserving surgery, and 6.3% chose mastectomy. The patients who chose IORT were more likely to receive endocrine treatment (odds ratio 3.70; p = 0.03). Age, race, language, and comorbidities were not associated with preference for IORT (p < 0.05).

CONCLUSIONS

Patients 65 years old or older with early-stage endocrine-responsive breast cancer preferred to have IORT despite counsel about the lack of survival benefit. This study suggests that local cancer control with the convenient radiation delivery method is important to the described patient population.

Intraoperative high dose rate brachytherapy during breast-conserving surgery: A Prospective Pilot Study

PURPOSE

To evaluate feasibility, quality of life, toxicity, and cosmetic outcome for intraoperative breast cancer brachytherapy after breast-conserving surgery using high dose rate brachytherapy.

METHODS AND MATERIALS

Fifty-two consecutive women, ⩾50 years old, diagnosed with a unifocal non-lobular breast cancer ⩽3 cm, N0, underwent breast-conserving surgery and sentinel node biopsy. Twenty-five women received intraoperative brachytherapy pre-pathology at primary surgery and the others post-pathology, during a second procedure. An applicator, connected to a high dose rate afterloader, was used. Two of the women were excluded due to metastases found per-operatively at a frozen section from the sentinel node. Quality of life was evaluated using two validated health questionnaires. Treatment toxicity was documented according to the LENT-SOMA scale by two oncologists. The cosmetic result was evaluated using the validated freely available software BCCT.core 2.0.

RESULTS

The clinical procedure worked out well logistically. Seven women received supplementary external radiotherapy due to insufficient margins and, in one case, poor adaptation of the breast parenchyma to the applicator. No serious adverse effects from irradiation were registered. The results from the health questionnaires showed no major differences compared with reference groups from the Swedish population. Only two women were registered as having a "poor" cosmetic result while a majority of the women had a "good" outcome.

CONCLUSION

This pilot study shows that intraoperative brachytherapy is a feasible procedure and encourages further trials evaluating its role in treatment of early breast cancer.

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.

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.

Keynote Address at the American Society of Breast Surgeons 18th Annual Meeting : Current and Future Application of Intraoperative Radiotherapy (IORT) in the Curative and Palliative Treatment of Breast Cancer

Intraoperative radiotherapy (IORT) is increasingly used worldwide. Breast cancer is the most rapidly growing indication for IORT, approaching 70-80% of cases in most centers. This report reviews the theoretical background and clinical use of IORT for primary and metastasized breast cancer. There are established applications such as tumor bed boost during breast-conserving surgery followed by whole breast radiotherapy or IORT as a form of accelerated partial-breast irradiation (APBI) for selected patients. Novel applications such as IORT for vertebral or brain metastases are presented as well as technological developments, widening the spectrum of potential clinical applications for IORT.

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.

Environmental and social benefits of the targeted intraoperative radiotherapy for breast cancer: data from UK TARGIT-A trial centres and two UK NHS hospitals offering TARGIT IORT

OBJECTIVE

To quantify the journeys and CO2 emissions if women with breast cancer are treated with risk-adapted single-dose targeted intraoperative radiotherapy (TARGIT) rather than several weeks' course of external beam whole breast radiotherapy (EBRT) treatment.

SETTING

(1) TARGIT-A randomised clinical trial (ISRCTN34086741) which compared TARGIT with traditional EBRT and found similar breast cancer control, particularly when TARGIT was given simultaneously with lumpectomy, (2) 2 additional UK centres offering TARGIT.

PARTICIPANTS

485 UK patients (249 TARGIT, 236 EBRT) in the prepathology stratum of TARGIT-A trial (where randomisation occurred before lumpectomy and TARGIT was delivered simultaneously with lumpectomy) for whom geographical data were available and 22 patients treated with TARGIT after completion of the TARGIT-A trial in 2 additional UK breast centres.

OUTCOME MEASURES

The shortest total journey distance, time and CO2 emissions from home to hospital to receive all the fractions of radiotherapy.

METHODS

Distances, time and CO2 emissions were calculated using Google Maps and assuming a fuel efficiency of 40 mpg. The groups were compared using the Student t test with unequal variance and the non-parametric Wilcoxon rank-sum (Mann-Whitney) test.

RESULTS

TARGIT patients travelled significantly fewer miles: TARGIT 21 681, mean 87.1 (SE 19.1) versus EBRT 92 591, mean 392.3 (SE 30.2); had lower CO2 emissions 24.7 kg (SE 5.4) vs 111 kg (SE 8.6) and spent less time travelling: 3 h (SE 0.53) vs 14 h (SE 0.76), all p<0.0001. Patients treated with TARGIT in 2 hospitals in semirural locations were spared much longer journeys (753 miles, 30 h, 215 kg CO2 per patient).

CONCLUSIONS

The use of TARGIT intraoperative radiotherapy for eligible patients with breast cancer significantly reduces their journeys for treatment and has environmental benefits. If widely available, 5 million miles (8 000 000 km) of travel, 170 000 woman-hours and 1200 tonnes of CO2 (a forest of 100 hectares) will be saved annually in the UK.

TRIAL REGISTRATION NUMBER

ISRCTN34086741; Post-results.

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 Versus Whole-Breast External Beam Radiotherapy in Early-Stage Breast Cancer: A Systematic Review and Meta-Analysis

There has not been a clear answer about the efficacy of intraoperative radiotherapy (IORT) for women with early-stage breast cancer.The aim of this meta-analysis was to summarize the available evidence comparing the efficacy and safety of IORT with those of whole-breast external beam radiotherapy (EBRT) for women with early-stage breast cancer.MEDLINE, EMBASE, the Web of Science, and the Cochrane Library were searched up to October 2014. Two authors independently conducted the literature selection and data extraction.Studies that compared IORT with whole-breast EBRT were included in the systematic review. IORT was defined as a single dose of irradiation to the tumor bed during breast-conserving surgery rather than whole-breast irradiation.Qualities of RCTs were evaluated according to the PEDro scale. Qualities of non-RCTs were evaluated according to the Methodological Index for Non-Randomized Studies (MINORS). The risk ratios (RRs) of ipsilateral breast tumor recurrence, overall mortality, breast cancer mortality, non-breast cancer mortality, and distant metastasis were pooled using a random-effects model.Four studies with 5415 patients were included in this meta-analysis, including 2 randomized controlled trials (RCTs) and 2 non-RCTs. Ipsilateral breast tumor recurrence was significantly higher in patients with IORT compared to those with whole-breast EBRT (RR 2.83, 95% CI 1.23-6.51), but with significant heterogeneity (I = 58.5%, P = 0.065). Comparing IORT with whole-breast EBRT, the pooled RRs for overall mortality, breast cancer mortality, non-breast cancer mortality, and distant metastasis were 0.88 (95% CI: 0.66-1.17), 1.20 (95% CI: 0.77-1.86), 0.76 (95% CI: 0.44-1.31), and 0.95 (95% CI: 0.61-1.49), respectively.IORT had a significantly higher risk of ipsilateral breast tumor recurrence than whole-breast EBRT. Overall mortality did not differ significantly. IORT should be used in conjunction with the prudent selection of suitable patients. It is imperative to identify women with a low risk of local recurrence.

miR-15b/16-2 regulates factors that promote p53 phosphorylation and augments the DNA damage response following radiation in the lung

MicroRNAs (miRNAs) are regulatory RNAs frequently dysregulated in disease and following cellular stress. Investigators have described changes in miR-15b expression following exposure to several stress-inducing anticancer agents, including ionizing radiation (IR), etoposide, and hydrogen peroxide. However, the role for miR-15b as a mediator of cellular injury in organs such as the lung has yet to be explored. In this study, we examined miR-15b expression patterns as well as its potential role in DNA damage and repair in the setting of IR exposure. We showed that miR-15b is up-regulated in a dose- and time-dependent manner in human bronchial epithelial cells following IR. miR-15b expression was highest after 2 h of IR and decreased gradually. Survival rates following IR were also higher in miR-15b/16-2-overexpressing cells. Cell cycle arrest in G2/M phase and an increased DNA repair response were observed in IR-exposed miR-15b/16-2 stable cells. We observed an up-regulation of components of the ataxia telangiectasia mutated (ATM)/Chek1/p53 pathway in miR-15b/16-2-overexpressing cells after IR. Moreover, a pathway-based PCR expression array of genes demonstrated that miR-15b/16-2 overexpression significantly induced the expression of genes involved in ATM/ataxia telangiectasia and Rad-3-related (ATR) signaling, apoptosis, the cell cycle, and DNA repair pathways. Here we demonstrated a novel biological link between miR-15b and DNA damage and cellular protection in lung cells. We identified Wip1 (PPM1D) as a functional target for miR-15b and determined that miR-15b induction of the DNA damage response is partially dependent upon suppression of Wip1. Our study suggests that miR-15b/Wip1 could be a potential therapeutic target in radiation-induced lung disease.