Evaluating Regional Nodal Irradiation Allocation and Association with Oncologic Outcomes in NSABP B-18, B-27, B-40, and B-41

Sentinel Lymph Node Biopsy in Early-Stage Breast Cancer: ASCO Guideline Update

PURPOSE

To update the ASCO evidence-based recommendations on the use of sentinel lymph node biopsy (SLNB) in patients with early-stage breast cancer treated with initial surgery.

METHODS

ASCO convened an Expert Panel to develop updated recommendations based on a systematic literature review (January 2016-May 2024).

RESULTS

Eleven randomized clinical trials (14 publications), eight meta-analyses and/or systematic reviews, and one prospective cohort study met the inclusion criteria for this systematic review. Expert Panel members used available evidence and informal consensus to develop practice recommendations.

RECOMMENDATIONS

Clinicians should not recommend routine SLNB in select patients who are postmenopausal and ≥50 years of age and with negative findings on preoperative axillary ultrasound for grade 1-2, small (≤2 cm), hormone receptor-positive, human epidermal growth factor receptor 2-negative breast cancer and who undergo breast-conserving therapy. Clinicians may offer postmastectomy radiation (RT) with regional nodal irradiation (RNI) and omit axillary lymph node dissection (ALND) in patients with clinically node-negative invasive breast cancer ≤5 cm who receive mastectomy and have one to two positive sentinel nodes. Clinicians may offer SLNB in patients who have cT3-T4c or multicentric tumors (clinically node-negative) or ductal carcinoma in situ treated with mastectomy, and in patients who are obese, male, or pregnant, or who have had prior breast or axillary surgery. Clinicians should not recommend ALND for patients with early-stage breast cancer who do not have nodal metastases, and clinicians should not recommend ALND for patients with early-stage breast cancer who have one or two sentinel lymph node metastases and will receive breast-conserving surgery and whole-breast RT with or without RNI.Additional information is available at www.asco.org/breast-cancer-guidelines.This guideline has been endorsed by the American Society for Radiation Oncology (ASTRO).

Third national surgical consensus conference of the Italian Association of Breast Surgeons (ANISC) on management after neoadjuvant chemotherapy: The difficulty in reaching a consensus

INTRODUCTION

Neoadjuvant chemotherapy (NAC) has a profound impact on surgical management of breast cancer. For this reason, the Italian Association of Breast Surgeons (ANISC) promoted the third national Consensus Conference on this subject, open to multidisciplinary specialists.

MATERIALS AND METHODS

The Consensus Conference was held on-line in November 2022, and after an introductory session with five core-team experts, participants were asked to vote on eleven controversial issues, while results were collected in real-time with a polling system.

RESULTS

A total of 164 dedicated specialists from 74 Breast Centers participated. Consensus was reached for only three of the eleven issues, including: 1) the indication to assess the response with Magnetic Resonance Imaging (79 %); 2) the need to re-assess the biological factors of the residual tumor if present (96 %); 3) the possibility of omitting a formal axillary node dissection for cN1 patients if a pathologic Complete Response (pCR) was confirmed with analysis of one or more sentinel lymph nodes (82 %). The majority voted in favor of mapping both the breast and nodal lesions pre-NAC (59 %), and against the omission of sentinel lymph node biopsy in cN0 patients in the case of pathologic or clinical Complete Response (69 %). In cases of cT3/cN1+ tumors with pCR, only 8 % of participants considered appropriate the omission of Post-Mastectomy Radiation Therapy.

CONCLUSION

There is still a wide variability in surgical approaches after NAC in the "real world". As NAC is increasingly used, multidisciplinary teams should be attuned to conforming their procedures to the rapid advances in this field.

Pediatric and Adolescent Hodgkin Lymphoma: Paving the Way for Standards of Care and Shared Decision Making

Hodgkin lymphoma (HL) is a treatable cancer with an incidence peak in adolescent and young adult years. Treatment strategies have been developed to balance the intensity of therapy needed to maintain disease-free survival while simultaneously preserving overall survival. Risk-based, response-adapted frontline therapy has long used a combination of chemotherapy and radiotherapy (RT). Successive clinical trials over the past three decades have safely reduced cumulative alkylator, anthracycline, and RT exposures for many patients. The advent of checkpoint inhibitors and the CD30-targeted antibody drug conjugate, brentuximab vedotin, has provided new options for de-escalation of conventional therapies associated with late effects in survivors treated at a young age. The ability to evaluate novel agents has been accelerated in collaborative trials inclusive of children and adolescents within the US National Clinical Trials Network and between the Children's Oncology Group and the EuroNet Pediatric Hodgkin Lymphoma Consortium. With numerous treatment options, patients with HL and their clinicians have an opportunity for shared decision making from diagnosis, through cancer treatment, and into survivorship. Given excellent survival outcomes, decisions about treatment in classic HL should be collaborative and attention to long-term survivorship needs should remain a high priority. Patient-reported outcomes remain an important tool to aid clinicians working with survivors to optimize health status and related quality of life for decades after HL therapy.

Essential requirements for reporting radiation therapy in breast cancer clinical trials: An international multi-disciplinary consensus endorsed by the European Society for Radiotherapy and Oncology (ESTRO)

The European Society for Radiotherapy and Oncology (ESTRO) has advocated the establishment of guidelines to optimise precision radiotherapy (RT) in conjunction with contemporary therapeutics for cancer care. Quality assurance in RT (QART) plays a pivotal role in influencing treatment outcomes. Clinical trials incorporating QART protocols have demonstrated improved survival rates with minimal associated toxicity. Nonetheless, in routine clinical practice, there can be variability in the indications for RT, dosage, fractionation, and treatment planning, leading to uncertainty. In pivotal trials reporting outcomes of systemic therapy for breast cancer, there is limited information available regarding RT, and the potential interaction between modern systemic therapy and RT remains largely uncharted. This article is grounded in a consensus recommendation endorsed by ESTRO, formulated by international breast cancer experts. The consensus was reached through a modified Delphi process and was presented at an international meeting convened in Florence, Italy, in June 2023. These recommendations are regarded as both optimal and essential standards, with the latter aiming to define the minimum requirements. A template for a case report form (CRF) has been devised, which can be utilised by all clinical breast cancer trials involving RT. Optimal requirements include adherence to predefined RT planning protocols and centralised QART. Essential requirements aim to reduce variations and deviations from the guidelines in RT, even when RT is not the primary focus of the trial. These recommendations underscore the significance of implementing these practices in both clinical trials and daily clinical routines to generate high-quality data.

CD24hiCD27+ Bregs within Metastatic Lymph Nodes Promote Multidrug Resistance in Breast Cancer

PURPOSE

Axillary lymph nodes (LN) are the primary and dominant metastatic sites in breast cancer. However, the interaction between tumor cells and immune cells within metastatic LNs (mLN) remains poorly understood. In our study, we explored the effect of CD24hiCD27+ regulatory B cells (Breg) within mLNs on orchestrating drug resistance of breast cancer cells.

EXPERIMENTAL DESIGN

We collected mLN samples from patients with breast cancer who had received standard neoadjuvant therapy (NAT) and analyzed the spatial features of CD24hiCD27+ Bregs through multicolor immunofluorescence staining. The effect of CD24hiCD27+ Bregs on drug resistance of breast cancer cells was evaluated via in vitro experiments. A mouse model with mLNs was used to evaluate the strategies with blocking the interactions between Bregs and breast cancer for improving tumor regression within mLNs.

RESULTS

In patients with breast cancer who had received NAT, there is a close spatial correlation between activated CD24hiCD27+ Bregs and residual tumor cells within mLNs. Mechanistically, CD24hiCD27+ Bregs greatly enhance the acquisition of multidrug resistance and stem-like features of breast cancer cells by secreting IL6 and TNFα. More importantly, breast cancer cells further promote the activation of CD24hiCD27+ Bregs via CD40L-dependent and PD-L1-dependent proximal signals, forming a positive feedback pattern. PD-L1 blockade significantly attenuates the drug resistance of breast cancer cells induced by CD24hiCD27+ Bregs, and addition of anti-PD-L1 antibody to chemotherapy improves tumor cell remission in mLNs.

CONCLUSIONS

Our study reveals the pivotal role of CD24hiCD27+ Bregs in promoting drug resistance by interacting with breast cancer cells in mLNs, providing novel evidence for an improved strategy of chemoimmunotherapy combination for patients with breast cancer with mLNs.

Children's Oncology Group's 2023 blueprint for research: Hodgkin lymphoma

The goal of therapy in pediatric Hodgkin lymphoma (HL) is to maximize overall survival while minimizing the morbidity of curative therapy. Key findings from recent Children's Oncology Group (COG) trials include: (i) superior event-free survival with the addition of brentuximab vedotin (Bv) in frontline regimens for high-risk disease, (ii) successful reduction in myeloablative regimens with demonstrated safety and efficacy of Bv and checkpoint inhibitor therapy in relapsed disease, and (ii) the potential to select a population that can be salvaged after relapse without receiving a stem cell transplant. The COG HL committee will lead a National cancer Institute National Clinical Trials Network phase 3 trial to evaluate the combination of Bv/nivolumab in early-stage disease. Ongoing advances in technology and blood biomarkers are increasing the ability to deliver biologically driven, personalized treatment for HL.

The 2022 Assisi Think Tank Meeting: White paper on optimising radiation therapy for breast cancer

The present white paper, referring to the 4th Assisi Think Tank Meeting on breast cancer, reviews state-of-the-art data, on-going studies and research proposals. <70% agreement in an online questionnaire identified the following clinical challenges: 1: Nodal RT in patients who have a) 1-2 positive sentinel nodes without ALND (axillary lymph node dissection); b) cN1 disease transformed into ypN0 by primary systemic therapy and c) 1-3 positive nodes after mastectomy and ALND. 2. The optimal combination of RT and immunotherapy (IT), patient selection, IT-RT timing, and RT optimal dose, fractionation and target volume. Most experts agreed that RT- IT combination does not enhance toxicity. 3: Re-irradiation for local relapse converged on the use of partial breast irradiation after second breast conserving surgery. Hyperthermia aroused support but is not widely available. Further studies are required to finetune best practice, especially given the increasing use of re-irradiation.

Regional radiotherapy after primary systemic treatment for cN+ breast cancer patients

Pathologic complete response (pCR) after Primary Systemic Treatment (PST) for breast cancer is associated with excellent long-term outcomes. With increasing use of PST, the indication for regional nodal irradiation (RNI) has been challenged. The aim of this paper is to review the literature on de-escalation of RNI in patients treated with PST. We found no level 1 evidence on de-escalation of RNI after PST, but several randomized trials are ongoing. Consequently, current de-escalation strategies are based on cohort studies. These studies showed that in patients with low nodal tumour burden (LNTB) (≤3 suspicious nodes at imaging) prior to PST, and ypN0 based on Axillary Lymph Node Dissection (ALND), omission of RNI resulted in very low regional recurrences (RR) without compromising survival. In patients with LNTB and ypN0 based on Sentinel Lymph Node Biopsy (SLNB), omission of axillary treatment also resulted in low RR; the majority of these patients received local radiotherapy. Similarly, in patients with ypN1 (ALND) disease, omission of RNI resulted in low 5-year RR rates. Low RR-rates were also found in the few studies replacing ALND by RNI, in patients with ypN1 (SLNB) disease. In patients with high nodal tumour burden prior to PST and ypN0 (SLNB), replacing ALND by RNI also resulted in low RR. Due to the limited number of patients, these data should be interpreted with caution. We conclude that although level 1 evidence is lacking, de-escalation of RNI after PST can be considered in selected cases.

Radiation therapy on the axilla after neoadjuvant chemotherapy

PURPOSE OF REVIEW

The introduction of primary systemic therapy has established a new treatment paradigm for breast cancer patients. However, recommendations for regional node irradiation after neoadjuvant chemotherapy are not supported by level I evidence, yet.

RECENT FINDINGS

In addition to strategies optimising systemic treatments and surgery, current discussions focus on tailoring radiation therapy for breast cancer. Especially in view of the increasingly pivotal role of neoadjuvant chemotherapy, gauging the extent of radiation therapy in the breast and nodal volumes.

SUMMARY

The current review focuses on recent evidence regarding radiation therapy of the breast and axilla in patients receiving neoadjuvant chemotherapy for primary breast cancer based on a PubMed and EMBASE literature search for publication years 2020-2022.