Effectiveness of different accelerated partial breast irradiation techniques for the treatment of breast cancer patients: Systematic review using indirect comparisons of randomized clinical trials

Breast cancer: an up-to-date review and future perspectives

Breast cancer is the most common cancer worldwide. The occurrence of breast cancer is associated with many risk factors, including genetic and hereditary predisposition. Breast cancers are highly heterogeneous. Treatment strategies for breast cancer vary by molecular features, including activation of human epidermal growth factor receptor 2 (HER2), hormonal receptors (estrogen receptor [ER] and progesterone receptor [PR]), gene mutations (e.g., mutations of breast cancer 1/2 [BRCA1/2] and phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha [PIK3CA]) and markers of the immune microenvironment (e.g., tumor-infiltrating lymphocyte [TIL] and programmed death-ligand 1 [PD-L1]). Early-stage breast cancer is considered curable, for which local-regional therapies (surgery and radiotherapy) are the cornerstone, with systemic therapy given before or after surgery when necessary. Preoperative or neoadjuvant therapy, including targeted drugs or immune checkpoint inhibitors, has become the standard of care for most early-stage HER2-positive and triple-negative breast cancer, followed by risk-adapted post-surgical strategies. For ER-positive early breast cancer, endocrine therapy for 5-10 years is essential. Advanced breast cancer with distant metastases is currently considered incurable. Systemic therapies in this setting include endocrine therapy with targeted agents, such as CDK4/6 inhibitors and phosphoinositide 3-kinase (PI3K) inhibitors for hormone receptor-positive disease, anti-HER2 targeted therapy for HER2-positive disease, poly(ADP-ribose) polymerase inhibitors for BRCA1/2 mutation carriers and immunotherapy currently for part of triple-negative disease. Innovation technologies of precision medicine may guide individualized treatment escalation or de-escalation in the future. In this review, we summarized the latest scientific information and discussed the future perspectives on breast cancer.

European Society for Radiotherapy and Oncology Advisory Committee in Radiation Oncology Practice consensus recommendations on patient selection and dose and fractionation for external beam radiotherapy in early breast cancer

High-quality randomised clinical trials testing moderately fractionated breast radiotherapy have clearly shown that local control and survival is at least as effective as with 2 Gy daily fractions with similar or reduced normal tissue toxicity. Fewer treatment visits are welcomed by patients and their families, and reduced fractions produce substantial savings for health-care systems. Implementation of hypofractionation, however, has moved at a slow pace. The oncology community have now reached an inflection point created by new evidence from the FAST-Forward five-fraction randomised trial and catalysed by the need for the global radiation oncology community to unite during the COVID-19 pandemic and rapidly rethink hypofractionation implementation. The aim of this paper is to support equity of access for all patients to receive evidence-based breast external beam radiotherapy and to facilitate the translation of new evidence into routine daily practice. The results from this European Society for Radiotherapy and Oncology Advisory Committee in Radiation Oncology Practice consensus state that moderately hypofractionated radiotherapy can be offered to any patient for whole breast, chest wall (with or without reconstruction), and nodal volumes. Ultrafractionation (five fractions) can also be offered for non-nodal breast or chest wall (without reconstruction) radiotherapy either as standard of care or within a randomised trial or prospective cohort. The consensus is timely; not only is it a pragmatic framework for radiation oncologists, but it provides a measured proposal for the path forward to influence policy makers and empower patients to ensure equity of access to evidence-based radiotherapy.

Adjuvant radiation therapy in breast cancer: Recent advances & Indian data

Breast cancer is the most common cancer among women in India, and adjuvant radiotherapy is an integral part of curative treatment in most patients. The recent decades have witnessed several advances in radiation therapy delivery. Several advances in radiation oncology have been identified which include technological advances, change in fractionation used, use of cardiac-sparing radiotherapy as well as efforts to personalize radiotherapy using accelerated partial breast irradiation or avoidance of radiotherapy in certain subpopulations. Indian data are available in most areas which have been summarized. However, increasing emphasis on research in these areas is needed so that effectiveness and safety in our setting can be established. Advances in breast cancer radiotherapy have resulted in improved outcomes. Data published from India suggest that these improved outcomes can be replicated in patients when appropriate treatment protocols are followed.

Intraoperative irradiation for early breast cancer (ELIOT): long-term recurrence and survival outcomes from a single-centre, randomised, phase 3 equivalence trial

BACKGROUND

In the randomised, phase 3 equivalence trial on electron intraoperative radiotherapy (ELIOT), accelerated partial breast irradiation (APBI) with the use of intraoperative radiotherapy was associated with a higher rate of ipsilateral breast tumour recurrence (IBTR) than whole-breast irradiation (WBI) in patients with early-stage breast cancer. Here, we aimed to examine the planned long-term recurrence and survival outcomes from the ELIOT trial.

METHODS

This single-centre, randomised, phase 3 equivalence trial was done at the European Institute of Oncology (Milan, Italy). Eligible women, aged 48-75 years with a clinical diagnosis of a unicentric breast carcinoma with an ultrasound diameter not exceeding 25 mm, clinically negative axillary lymph nodes, and who were suitable for breast-conserving surgery, were randomly assigned (1:1) via a web-based system, with a random permuted block design (block size of 16) and stratified by clinical tumour size, to receive post-operative WBI with conventional fractionation (50 Gy given as 25 fractions of 2 Gy, plus a 10 Gy boost), or 21 Gy intraoperative radiotherapy with electrons (ELIOT) in a single dose to the tumour bed during surgery. The trial was open label and no-one was masked to treatment group assignment. The primary endpoint was the occurrence of IBTR. The trial was designed assuming a 5-year IBTR rate of 3% in the WBI group and equivalence of the two groups, if the 5-year IBTR rate in the ELIOT group did not exceed a 2·5 times excess, corresponding to 7·5%. Overall survival was the secondary endpoint. The main analysis was done by intention to treat. The cumulative incidence of IBTR events and overall survival were assessed at 5, 10, and 15 years of follow-up. This trial is registered with ClinicalTrials.gov, NCT01849133.

FINDINGS

Between Nov 20, 2000, and Dec 27, 2007, 1305 women were enrolled and randomly assigned: 654 to the WBI group and 651 to the ELIOT group. After a median follow-up of 12·4 years (IQR 9·7-14·7), 86 (7%) patients developed IBTR, with 70 (11%) cases in the ELIOT group and 16 (2%) in the WBI group, corresponding to an absolute excess of 54 IBTRs in the ELIOT group (HR 4·62, 95% CI 2·68-7·95, p<0·0001). In the ELIOT group, the 5-year IBTR rate was 4·2% (95% CI 2·8-5·9), the 10-year rate was 8·1% (6·1-10·3), and the 15-year rate was 12·6% (9·8-15·9). In the WBI group, the 5-year IBTR rate was 0·5% (95% CI 0·1-1·3), the 10-year rate was 1·1% (0·5-2·2), and the 15-year rate was 2·4% (1·4-4·0). At final follow-up on March 11, 2019, 193 (15%) women had died from any cause, with no difference between the two groups (98 deaths in the ELIOT group vs 95 in the WBI group; HR 1·03, 95% CI 0·77-1·36, p=0·85). In the ELIOT group, the overall survival rate was 96·8% (95% CI 95·1-97·9) at 5 years, 90·7% (88·2-92·7) at 10 years, and 83·4% (79·7-86·4) at 15 years; and in the WBI group, the overall survival rate was 96·8% (95·1-97·9) at 5 years, 92·7% (90·4-94·4) at 10 years, and 82·4% (78·5-85·6) at 15 years. We did not collect long-term data on adverse events.

INTERPRETATION

The long-term results of this trial confirmed the higher rate of IBTR in the ELIOT group than in the WBI group, without any differences in overall survival. ELIOT should be offered to selected patients at low-risk of IBTR.

FUNDING

Italian Association for Cancer Research, Jacqueline Seroussi Memorial Foundation for Cancer Research, Umberto Veronesi Foundation, American Italian Cancer Foundation, The Lombardy Region, and Italian Ministry of Health.

Breast cancer

Breast cancer is the most frequent malignancy in women worldwide and is curable in ~70-80% of patients with early-stage, non-metastatic disease. Advanced breast cancer with distant organ metastases is considered incurable with currently available therapies. On the molecular level, breast cancer is a heterogeneous disease; molecular features include activation of human epidermal growth factor receptor 2 (HER2, encoded by ERBB2), activation of hormone receptors (oestrogen receptor and progesterone receptor) and/or BRCA mutations. Treatment strategies differ according to molecular subtype. Management of breast cancer is multidisciplinary; it includes locoregional (surgery and radiation therapy) and systemic therapy approaches. Systemic therapies include endocrine therapy for hormone receptor-positive disease, chemotherapy, anti-HER2 therapy for HER2-positive disease, bone stabilizing agents, poly(ADP-ribose) polymerase inhibitors for BRCA mutation carriers and, quite recently, immunotherapy. Future therapeutic concepts in breast cancer aim at individualization of therapy as well as at treatment de-escalation and escalation based on tumour biology and early therapy response. Next to further treatment innovations, equal worldwide access to therapeutic advances remains the global challenge in breast cancer care for the future.

Highlights of the 16th St Gallen International Breast Cancer Conference, Vienna, Austria, 20-23 March 2019: personalised treatments for patients with early breast cancer

The 16th St Gallen International Breast Cancer Conference took place in Vienna for the third time, from 20–23 March 2019. More than 3000 people from all over the world were invited to take part in this important bi-annual critical review of the ‘state of the art’ in the primary care of breast cancer (BC), independent of political and industrial pressure, with the aim to integrate the most recent research data and most important developments in BC therapies since St Gallen International Breast Cancer Conference 2017, with the ultimate goal of drawing up a consensus for the current optimal treatment and prevention of BC.

This year, the St Gallen Breast Cancer Award was won by Monica Morrow (Memorial Sloan Kettering Cancer Center, USA) for her extraordinary contribution in research and practise development in the treatment of BC. She opened the session with the lecture ‘Will surgery be a part of BC treatment in the future?’ Improved systemic therapy has decreased BC mortality and increased pathologic complete response (pCR) rates after neoadjuvant chemotherapy (NACT). Improved imaging and increased screening uptake have led to detect smaller cancers. These factors have highlighted two possible scenarios to omit surgery: for patients with small low-grade ductal carcinoma in situ (DCIS) and for those who have received NACT and had a clinical and radiological complete response. However, considering that 7%–20% of `low-risk’ DCIS patients have co-existing invasive cancer at diagnosis, that surgery has become progressively less morbid and less toxic than some systemic therapies with a lower cost-effectiveness ratio, and that identification of pathologic complete response (pCR) without surgery requires more intensive imaging follow-up (more biopsies, higher cost and more anxiety for the patient), surgery still appears to be an essential treatment for BC.

The Umberto Veronesi Memorial Award went to Lesley Fallowfield (Brighton and Sussex Medical School, UK) for her important research and activity in the field of the development of patient outcome, of better communication skills and quality of life for women. In her lecture, she remarked on the importance of improving BC personalised treatments, especially through co-operation between scientists, always considering the whole woman and not just her breast disease. This award was given by Paolo Veronesi, after a moving introduction which culminated with the following words of Professor Umberto Veronesi:

‘It is not possible to take care of the people’s bodies without taking care of their mind. My duty, the duty of all doctors, is to listen and be part of the emotions of those we treat every day’.