Optimization ...h node biopsy_Zhao Bi.pdf

Cancer Biol Med 2023.doi:10.20892/j.issn.2095-3941.2022.0625EDITORIALOptimization of regional nodal irradiation in the era of sentinel lymph node biopsyZhao Bi1,Xueer Wang2,Pengfei Qiu1,Peng Chen1,Yongsheng Wang11Shandong Cancer Hospital and Institute,Shandong First Medical University and Shandong Academy of Medical Sciences,Jinan 250017,China;2Tianjin Medical University Cancer Institute&Hospital,National Clinical Research Center for Cancer,Key Laboratory of Cancer Prevention and Therapy,Tianjin,Tianjins Clinical Research Center for Cancer,Tianjin 300060,ChinaHistorically,axillary lymph node dissection(ALND)was the standard management for axillary sentinel lymph node(SLN)-positive patients,because it enables full assessment of overall axillary lymph node(ALN)metastasis status and favorable local-regional control1,2.Strikingly,no differences in axillary regional recurrence or overall survival(OS)have been observed with versus without ALND among patients with early breast cancer with limited SLN involvement in several randomized,controlled trials,including the ACSOG Z0011 and AMAROS trial3,4.In the era of sentinel lymph node biopsy(SLNB),SLNB has replaced ALND as the standard approach for patients with 1 or 2 positive SLNs5.These changes in clin-ical practice should be considered for the optimization of regional nodal irradiation(RNI)fields.“Intelligent de-escalation”irradiation strategy in the era of SLNBIn the era of SLNB,the benefits of systemic therapy and radi-ation therapy can be combined to narrow the scope of sur-gery and decrease complications,thus ultimately achieving a net benefit with breast cancer treatment.Postmastectomy radiotherapy(PMRT)or RNI has advantages of avoiding ALND,but exposes patients to potentially acute or long-term toxic complications(including rare but potentially fatal sec-ond cancers and cardiac events)6.Decisions regarding the choice of ALND and radiotherapy must be made by a multi-disciplinary team.The Memorial Sloan Kettering Cancer Center7 has proposed an“intelligent de-escalation”strat-egy in which the numbers of lymph node metastases and risk factors are used to determine whether patients should receive PMRT or RNI.The risk factors include primary fac-tors age 3 cm,high Oncotype DX index,age 4050 years,LVI,and lymph node exocellular invasion 2 cm).Patients with one lymph node metastasis receive PMRT or RNI if they have extensive LVI,triple negative breast cancer,age 40 years,or 3 secondary factors.Patients with 2 lymph node metastases receive PMRT or RNI if they have any pri-mary factors,LVI,age 4050 years,or 2 secondary factors.However,patients with 3 lymph node metastases receive PMRT or RNI regardless of any associated risk factors.Therefore,for patients with 1 or 2 positive SLNs,the fol-lowing strategies are recommended:(1)for patients receiv-ing breast conserving surgery,ALND should be avoided,because postoperative radiation is required;(2)for patients with pN0/pNmic disease undergoing mastectomy,further axillary surgery is not acceptable;(3)if PMRT is clearly required after mastectomy for patients with 1 or 2 posi-tive SLNs,individualized treatment should be performed according to the wishes of the patient,the occurrence of upper limb edema,radiotherapy costs and complications,the probability of non-SLN(nSLN)metastasis,and tumor burden;and(4)if the indications for PMRT are unclear after mastectomy,patients should receive ALND.Correspondence to:Yongsheng WangE-mail:ORCID ID:https:/orcid.org/0000-0001-6252-684XReceived October 10,2022;accepted December 13,2022Available at www.cancerbiomed.org2023 Cancer Biology&Medicine.Creative Commons Attribution-NonCommercial 4.0 International License90 Bi et al.Optimization of RNI in the era of SLNBOptimization of RNI fields in the era of SLNBIn the era of SLNB,with the widespread application of the newer approach described above,related changes in clinical practice should also be considered the optimization of radio-therapy fields.The Z0011 and AMAROS trials have shown that omission of ALND,followed by radiotherapy and adjuvant systemic therapy,is safe and produces no difference in regional recurrence in patients with early breast cancer and limited SLN involvement3,4.Axillary recurrence has been shown to be low,even in patients undergoing axillary de-escalation surgery,thereby suggesting that tumor biology,adjuvant systemic ther-apy,and radiation therapy may potentially play crucial roles8.Additional local control may also prolongs survival when sys-temic treatment is effective.In the SLNB group in the Z0011 trial,patients received high-tangential whole-breast irradia-tion.For patients assigned to ALND,no further axillary spe-cific intervention and no nodal irradiation were performed3.In the SLNB group in the AMAROS trial,RNI included the con-tents of all 3 levels of the axilla as well as the medial part of the supraclavicular fossa.Adjuvant RNI after ALND was allowed when at least 4 positive nodes were found(8%of the entire po