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👉A mastectomy is an operation to remove all of the breast tissue from a breast as a way to treat or prevent cancer.

👉Mastectomy can be a treatment option for many types of cancer:

• Ductal carcinoma in situ or non-invasive breast cancer
• Stage I and II (early stage) breast cancer
• Stage III (locally advanced) breast cancer, after chemotherapy
• Inflammatory breast cancer, after chemotherapy
• Paget’s disease of the breast
• Locally recurring breast cancer

👉Breast-conserving surgery (partial mastectomy/ lumpectomy), in which only the tumor is removed with negative margins, may be another option.

👉Newer mastectomy techniques can preserve the skin of the breast and allow it to have a more natural appearance – Skin sparing mastectomy

👉Newer mastectomy techniques can preserve the nipple areolar complex of the breast allowing it to have a more natural appearance – Nipple sparing mastectomy

👉Surgery to restore the shape of the breast, called breast reconstruction, can be done at the same time as the mastectomy or during a second operation.

#Arrangoiz #BreastSurgeon #BreastCancer #CancerSurgeon

• Surgical excision of an area of atypical duct hyperplasia (ADH) found on core needle biopsy:
  • Is recommended to rule out underlying occult breast cancer:
    • Which can be found in 15% to 30% of patients
• Studies consistently show higher rates of upgrade to DCIS (2/3 of the cases) compared to invasive carcinoma (1/3 of the cases)
• A multivariable model assessing predictors for risk of upgrade at the time of excision of ADH found that:
  • Lesions that were less than 50% removed by core biopsy, compared to those with greater than 90% removed:
    • Had a significantly higher risk of upgrade (OR 3.8)
  • Similarly, ADH with individual cell necrosis (OR 4.3) and with multiple foci of atypia on core biopsy (OR 2-3 foci 2.1; OR >3 foci 3.6 compared to 1 foci) were more likely to have a subsequent upgrade
• ADH is associated with an increased risk of future development of breast cancer when identified on a core needle biopsy or at time of surgery:
  • With a relative risk of approximately 4
• Increasing number of foci of atypia:
  • Has also been reported to be associated with increasing future breast cancer risk
• A study by Degnim and colleagues combined outcomes for women with a history of atypical hyperplasia from the Mayo Clinic and the Nashville Cohort:
  • In the combined analysis, among women with ADH, the relative risk of breast cancer was 2.65 with 1 foci, 5.19 with 2 foci, and 8.94 with >3 foci, p<.001
• As the vast majority of subsequent cancers in this population are estrogen positive:
  • Patients with ADH may benefit from chemoprevention as demonstrated in the NSABP P-1 study:
    • Which demonstrated a 49% reduction in the development of invasive breast cancer in high-risk patients with the use of tamoxifen compared to placebo (p<0.00001), with the greatest benefit seen in women with atypical hyperplasia or lobular carcinoma in situ:
      • However, tamoxifen did not effect overall survival
• References
  • Mooney K, Bassett LW, Apple SK. Upgrade rates of high-risk breast lesions diagnosed on core needle biopsy: a single-institution and literature review. Modern Pathol. 2016;29(12):1471-1484.
  • Pena A, Shah SS, Fazzio RT, Hoskin TL, Brahmbhatt RD1, Hieken TJ, at al. Multivariate model to identify women at low risk of cancer upgrade after a core needle biopsy diagnosis of atypical ductal hyperplasia. Breast Cancer Res Treat.2017;164(2):295-304.
  • Hartmann LC, Degnim AC, Santen RJ, Dupont WD, Ghosh K. Atypical hyperplasia of the breast – risk assessment and management options. NEJM. 2015;372(1):78-89.
  • Degnim AC, Dupont WD, Radisky DC, et al. Extent of atypical hyperplasia stratifies breast cancer risk in 2 independent cohorts of women. Cancer. 2016;122(19):2971-2978.

Local recurrence in the breast may be accompanied by distant recurrence. Therefore, all patients who are diagnosed with a local or regional recurrence should have staging scans to rule out distant disease. If these scans are negative, surgical intervention is recommended if the tumor is operable.

In patients who develop an ipsilateral breast recurrence or new primary tumor following prior history of breast conservation with whole breast radiation therapy, further radiation is generally contraindicated. Therefore, the standard surgical treatment of the breast is mastectomy. While there have been case reports of repeat lumpectomy followed by accelerated partial-breast radiation therapy, there are insufficient data to support the long-term safety of this approach. If the tumor is not operable by mastectomy at presentation, neoadjuvant therapy with chemotherapy or hormone therapy may be considered as an initial step.

The approach to the axillary lymph nodes has been an area of debate since the era of SLNB. Nodal staging provides valuable prognostic information, even in the case of a local recurrence. If a patient is clinically node-negative at the time she presents with a local recurrence in the breast, SLNB may be attempted. There is a small body of literature supporting the use of reoperative SLNB in clinically node-negative patients who have an ipsilateral recurrence or new primary following prior breast conservation with SLNB. These studies have found that successful lymphatic mapping is more likely to occur when fewer nodes were removed at the time of the treatment for the index cancer. While lymphoscintography is not strictly required, it may help to identify sites of extra-axillary drainage due to alternate drainage pathways. In patients who have had prior completion axillary lymph node dissection, reoperative SLNB is possible, but less likely to be associated with successful lymphatic mapping. In these cases, axillary exploration is less likely to yield any additional lymph nodes.

Cardosa F, Fallowfield L, Costa A, et al; and ESMO Guidelines Working Group. Locally recurrent or metastatic breast cancer: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up. Ann Oncol. 2011;22(Suppl 6):vi25-vi30.

Cox CE, Furman BT, Kiluk JV, et al. Use of reoperative sentinel lymph node biopsy in breast cancer patients. J Am Coll Surg. 2008;207:57-61.

Karam A, Stempel M, Cody HS III, Port ER. Reoperative sentinel lymph node biopsy after previous mastectomy. J Am Coll Surg. 2008;207:543-548.

Kaur P, Kiluk JV, Meade T, et al. Sentinel lymph node biopsy in patients with previous ipsilateral complete axillary lymph node dissection. Ann Surg Oncol. 2011;18:727-732.

Port E, Garcia-Etienne C, Park J, Fey J, Borgen PI, Cody HS 3rd. Reoperative sentinel lymph node biopsy: a new frontier in the management of ipsilateral breast tumor recurrence. Ann Surg Oncol. 2007;14:2209-2214.

• Patients enrolled in the NSABP B-17 trial:
  • Were randomly assigned to receive:
    • Partial mastectomy only or partial mastectomy followed by lattice radiotherapy (LRT; a novel technique of delivering heterogeneous doses of radiation to voluminous tumors not amenable to surgery) for the treatment of localized DCIS
  • The trial showed a clear benefit for the addition of radiation
• Patients enrolled in the NSABP B-24 trial:
  • Were randomly assigned to receive LRT or LRT plus tamoxifen (LRTT)
• At 15-year follow-up:
  • The risk of death in these trials was low:
    • Ranging from 2.3% for patients who had LRTT to 4.7% for patients who had LRT
  • Ipsilateral breast tumor recurrence was:
    • 35% (19.6% invasive, 15.4% DCIS) in the lumpectomy only arm of B-17 and 19.8% (10.7% invasive, 9.0% DCIS) in the LRT arm
    • In B-24 IBRT was 16.6% (9.0 invasive, 7.6% DCIS) in the LRT arm and 13.2% (6.6% invasive, 6.7% DCIS) in the LRTT arm
  • The risk of contralateral new primary ranged from:
    • 4.9% (3.3% invasive, 1.6% DCIS) in the LRTT arm of B-24 to 9.3% (5.6% invasive, 3.7% DCIS) in the LRT arm of B-17
• References:
  • Wapnir IL, Dignam JJ, Fisher B, Mamounas EP, Anderson SJ, Julian TB, et al. Long-term outcomes of invasive ipsilateral breast tumor recurrences after lumpectomy in NSABP B-17 and B-24 randomized clinical trials for DCIS. J Natl Cancer Inst. 2011;103(6):478-488.

#Arrangoiz #BreastSurgeon #BreastCancer #CancerSurgeon #Teacher #SurgicalOncologist #Miami #Mexico #DCIS

Bottom line: In carefully selected patients (typically older, ER+/HER2–, node-negative, small tumors on endocrine therapy), skipping whole-breast radiotherapy (RT) raises local recurrence modestly but does not worsen overall survival in long-term randomized data. 

Key randomized signals (10-year):

• PRIME II (age ≥65, HR+, ≤3 cm, node-negative, endocrine therapy): local recurrence 9.5% without RT vs 0.9% with RT; no difference in distant recurrence or overall survival (~81% both arms). 

• CALGB 9343 (age ≥70, T1N0 ER+): local/regional control higher with RT (98% vs 90%) but no differences in time to mastectomy, distant metastasis, breast cancer-specific survival, or OS (67% vs 66%). 

Meta-analytic perspective: Syntheses focused on randomized trials consistently show RT substantially lowers local recurrence after breast-conserving surgery, with minimal or no OS impact in these low-risk cohorts—informing shared decisions when a patient prioritizes avoiding RT toxicity or logistics. 

Who may be appropriate to consider for omission?

• Age ≥65–70, ER+, HER2–, pT1, node-negative, clear margins, committed to endocrine therapy; ideally with a reassuring axillary assessment and low-risk biology. (Emerging prospective cohorts like LUMINA/IDEA support expanding biologic selection but are not RCTs.) 

Why this matters for patients:

• Fewer visits, less fatigue/dermatitis, and lower long-term toxicity burden—without sacrificing survival in the right subset. 

Practical takeaways for clinic:

Discuss omission for the classic low-risk profile above; quote absolute local-recurrence trade-offs (e.g., ~9–10% vs ~1% at 10 years in PRIME II).  If RT is preferred or biology is borderline, consider de-escalated RT (partial-breast or 5-fraction regimens) to cut burden while preserving control.  Use shared decision-making; align with patient goals, comorbidity, adherence to endocrine therapy, and imaging/pathology risk features. 

#BreastCancer #RadiationOncology #Deescalation #SharedDecisionMaking #Oncology

#Arrangoiz

• Framing the Question:
  • Clinical question:
    • In women with invasive breast cancer ≤ 2 cm, clinically node-negative and axillary ultrasound (AUS) negative:
      • Is omitting axillary surgery non-inferior to sentinel lymph node biopsy (SLNB):
        • For 5-year distant disease-free survival (DDFS)? JAMA Network
  • Why this matters now:
    • ACOSOG Z0011:
      • Showed no therapeutic benefit for ALND over less surgery (SLNB alone):
        • The next logical step tests whether staging itself (SLNB) can be omitted:
          • When it won’t change adjuvant plans:
            • Reducing morbidity without compromising oncologic safety JAMA Network
• Study Design Essentials:
  • Design:
    • Prospective, multicenter, phase 3 non-inferiority RCT:
      • 1:1 randomization to:
        • No axillary surgery vs SLNB
    • Primary endpoint:
      • 5-yr distant disease free survival (DDFS) (ITT)
    • Secondary:
      • Disease free survival (DFS)
      • Overal survival (OS)
      • Cumulative incidence of distant and axillary recurrences, and adjuvant treatment recommendations JAMA Network
  • Setting and timeline:
    • 18 hospitals in:
      • Italy, Spain, Switzerland, and Chile
    • Enrollment Feb 2012 to Jun 2017
    • Analysis 2022 to 2023 JAMA Network
  • Eligibility (PICO):
    • Women of any age
    • Tumor ≤ 2 cm
    • cN0 by exam
    • Negative AUS:
      • Suspicious nodes required cytology to exclude metastasis
    • Breast-conserving surgery (BCS) common, with radiotherapy permitted:
      • Including partial breast and IORT
    • ITT N = 1,405:
      • SLNB 708
      • Omit 697
    • Median age 60
    • Median tumor 1.1 cm
    • ~ 88% ER+ / HER2 –  JAMA Network
  • AUS as a triage tool:
    • Despite variable sensitivity in literature:
      • Negative AUS in the SOUND trial effectively ruled out heavy nodal burden:
        • SLNB arm had 13.7% any nodal metastasis but only 0.6% had ≥ 4 positive nodes
        • Axillary recurrence 0.4% at 5 years in both arms JAMA Network
• Statistics You Should Know:
  • Non-inferiority setup:
    • Primary analysis ITT:
      • NI margin 2.5% for 5-year DDFS; HR with 90% CI and one-sided NI P-value
      • Assumed 5-year DDFS ≈ 96.5%:
        • Observed outcomes were higher, increasing power to show NI if risks are truly similar JAMA Network
  • Follow-up:
    • Median follow-up for disease assessment 5.7 years in both arms JAMA Network
• Results (with absolute numbers):
  • Primary endpoint (DDFS):
    • 5-year DDFS: 
      • 97.7% (SLNB) vs 98.0% (No surgery):
        • HR 0.84, 90% CI 0.45–1.54; P for non-inferiority = 0.02:
          • Two-arm difference not significant by log-rank (P=0.67) JAMA Network
  • Secondary endpoints:
    • 5-year DFS: 
      • 94.7% (SLNB) vs 93.9% (No surgery), P=0.30.
    • 5-year OS: 
      • 98.2% (SLNB) vs 98.4% (No surgery), P=0.72 JAMA Network
    • Regional control (events are rare):
      • 5-year cumulative axillary recurrence = 0.4% in each arm (Gray P=0.91)
    • Locoregional relapse: 
      • 1.7% (SLNB) vs 1.6% (No surgery) JAMA Network
    • Absolute event counts:
      • SLNB: 
        • 13 distant metastases (1.8%), 21 deaths (3.0%).
      • No surgery: 
        • 14 distant metastases (2.0%), 18 deaths (2.6%) JAMA Network
    • Adjuvant therapy impact:
      • No material differences in systemic therapy or RT use between arms:
        • Supporting that, in this AUS-negative group:
          • Pathologic nodal information didn’t drive adjuvant decisions JAMA Network
      • Radiotherapy details:
        • All RT options allowed, including partial breast / IORT
        • Notably, 114 patients (16.3%) in the no-surgery arm received ELIOT (full-dose or boost)
        • Despite this heterogeneity:
          • Axillary failures stayed 0.4% at 5 years in both arms JAMA Network
  • How often was SLNB positive?
    • 13.7% had any nodal metastasis in the SLNB arm (micro + macro metasteses)
    • Heavy burden (≥ 4 nodes) was 0.6% JAMA Network
• Interpretation and External Context:
  • Plain-English bottom line:
    • For AUS-negative, ≤ 2 cm, cN0 tumors planned for BCS + RT:
      • Skipping SLNB is non-inferior for 5-yearr DDFS:
        • With no increase in axillary failures and no detectable survival trade-off – and you avoid the morbidity of axillary surgery JAMA Network
• How does the SOUND trial line up with INSEMA trial (NEJM 2024/2025)?:
  • INSEMA broadened to T1 to T2 ≤ 5 cm BCT patients and used invasive DFS as the primary endpoint:
    • Omission was non-inferior with lower arm morbidity – reinforcing the SLNB – omission strategy for selected cN0 BCT candidates New England Journal of Medicine+2PubMed+2
• Generalizability – who are “SOUND-like” in clinic?
  • Mostly small (T1 / ≤ 2 cm), HR+ / HER2 –  tumors, negative AUS, upfront BCS + RT:
    • Adjuvant decisions unlikely to change with nodal micrometastatic information:
      • Authors estimate ~ 25% of all breast cancer (BC) cases may fit these criteria JAMA Network
• Potential practice impact:
  • With ~ 2.3 M new BC cases / year, ~ 500,000 patients globally could avoid axillary surgery:
    • Improving early arm function and reducing lymphedema risk without oncologic compromise JAMA Network
• Limitations and Caveats:
  • Low-risk enrichment:
    • Mostly small, ER+ / HER2- tumors:
      • Short-to-mid-term risk low:
        • Longer follow-up always helpful JAMA Network
  • Adjuvant therapy analysis not powered:
    • Differences in systemic / RT nuances might be too small to detect:
      • Adjuvant-recommendation analysis was secondary JAMA Network
  • Late trial registration noted:
    • Registered after enrollment began; protocol / statistical plan were peer-review-published, and authors state no interim looks occurred; still worth acknowledging JAMA Network
  • Radiation heterogeneity (including IORT):
    • Permissive RT techniques (e.g., ELIOT) could theoretically influence local / axillary outcomes:
      • Nonetheless axillary failure remained 0.4% in both arms JAMA Network
  • Not for neoadjuvant or mastectomy:
    • SOUND trial did not test patients planned for neoadjuvant systemic therapy or mastectomy without conventional whole-breast RT:
      • Avoid extrapolating JAMA Network
  • Young HR+ / HER2- patients (Rx-PONDER context):
    • In some premenopausal HR+ / HER2- patients:
      • Nodal positivity can still influence chemo or endocrine therapy type / duration:
        • If nodal information truly changes systemic therapy:
          • SLNB may remain reasonable JAMA Network
• Apply in Clinic” Checklist (What to document):
  • Who qualifies for omission (SOUND-style)?
    • Tumor ≤ 2 cm
    • cN0 on exam
    • Negative AUS (suspicion cleared by cytology)
    • Upfront BCS + RT planned
    • Adjuvant plan won’t change with nodal micro-staging
    • Document shared decision-making:
      • Cite SOUND + INSEMA JAMA Network+1]
  • Who should still get SLNB?
    • Neoadjuvant candidates (different evidence base)
    • Mastectomy without standard whole-breast RT
    • Cases where nodal status alters chemotherapy / Endocrine therapy decisions:
      • Younger HR+ / HER2-
    • AUS positive / suspicious nodes not cleared by cytology JAMA Network
  • How to counsel about risk:
    • Explain that with negative AUS, the chance of heavy nodal disease is very low (≥ 4 nodes 0.6% in SLNB arm), and axillary recurrence at 5 years ~ 0.4% without surgery – the same as with SLNB JAMA Network
  • Quick Numbers Box:
    • ITT N=1,405 (708 SLNB; 697 No surgery):
      • Median f/u 5.7 yrs. JAMA Network
    • 5-yr DDFS: 
      • 97.7% vs 98.0% (HR 0.84; 90% CI 0.45–1.54; NI P=0.02) JAMA Network
    • 5-yr DFS: 
      • 94.7% vs 93.9% (P=0.30)
    • 5-yr OS: 98.2% vs 98.4% (P=0.72) JAMA Network
    • Axillary recurrence (5 yrs): 
      • 0.4% vs 0.4%
    • SLN+ (any):
      • 13.7%
    • ≥ 4 nodes:
      • 0.6% JAMA Network
    • RT nuance: 
      • 16.3% of omission arm received ELIOT (full-dose / boost) JAMA Network
• Discussion Starters:
  • Endpoint choice: 
    • Was DDFS the best primary endpoint versus iDFS or regional failure:
      • SOUND chose DDFS to reflect oncologic safety independent of local RT nuances JAMA Network
  • Imaging vs surgery: 
    • Does negative AUS sufficiently replace pathologic staging in 2025 clinics, especially with modern systemic therapy selection? JAMA Network
  • RT heterogeneity: 
    • Could permissive RT (including IORT) have “rescued” regional control?
      • If so, why are axillary failures identically rare in both arms? JAMA Network
  • Younger HR+ / HER2- patients: 
    • Where do you draw the line for still doing SLNB given Rx-PONDER-type considerations? JAMA Network
  • Global impact: 
    • How would your clinic operationalize AUS-triaged omission (workflow, sonographer QA, documentation templates)? JAMA Network
  • How SOUND Aligns with INSEMA (one-paragraph takeaway):
    • INSEMA (NEJM 2024/2025) randomized cN0 BCT patients (T1 to T2 ≤ 5 cm) to omission vs SLNB:
      • Invasive DFS primary outcome was non-inferior, with less arm morbidity in the omission group
    • Together with SOUND (DDFS primary, ≤ 2 cm, AUS-negative), these trials support AUS-triaged omission of SLNB in carefully selected early breast cancers planned for BCS + RT New England Journal of Medicine+2PubMed+2
      
      

• As reported by Veronesi in 1999:
  • 737 patients were randomized to either undergo Halsted mastectomy or extended mastectomy with IM node dissection
  • After 30 years of follow-up:
    • There was no difference in overall survival or disease-specific survival:
      • For the patients eligible with T1, T2, T3, N0, and N1 disease:
        • Who underwent IM node dissection vs. no IM dissection
• A 2019 retrospective review of 95 breast cancer patients with clinically detected IM nodes (IMNs) at diagnosis:
  • Were treated with surgery and radiation, with median follow-up of 43 months:
    • 77 received neoadjuvant chemotherapy:
      • With IMN normalization in 67.5%
      • Partial IMN response in 24.6%
  • The 5-year IMN failure-free survival, disease-free survival, and overall survival were:
  • 96%, 70%, and 84%, respectively
    • IMN failure-free survival:
      • Was significantly affected by:
        • Resection margin status
        • Size of IMN
        • Receipt of IMN boost radiation
• A recently published meta-analysis in the Annals of Surgery found that axillary staging following neoadjuvant chemotherapy:
  • Is best performed with a combination approach of sentinel lymph node biopsy (SLNB) with excision of the pre-chemotherapy-marked positive node:
    • With a false negative rate of 2% to 4%:
      • The identification rate was 100%
• ACOSOG Z1071:
  • Reported an overall false negative rate of 12.6% when SLNB was performed after neoadjuvant chemotherapy with documented node-positive disease prior to treatment:
    • The false-negative rate decreased to 6.8%:
    • When both sentinel node(s) and the clipped node were retrieved at the time of surgery
• References:
  • Veronesi U, Marubini E, Mariani L, Valagussa P, Zucali R. The dissection of internal mammary nodes does not improve the survival of breast cancer patients. 30-year results of a randomised trial. Eur J Cancer. 1999;35(9):1320-1325.
  • Kim J, Chang JS, Choi SH, et.al. Radiotherapy for initial clinically positive internal mammary nodes in breast cancer. Radiat Oncol J. 2019;37(2):91-100.
  • Simons JM, van Nijnatten TJA, van der Pol CC, Luiten EJT, Koppert LB, Smidt ML. Diagnostic accuracy of different surgical procedures for axillary staging after neoadjuvant systemic therapy in node-positive breast cancer: a systematic review and meta-analysis. Ann Surg. 2019;269(3):432-442.
  • Boughey JC, Ballman KV, Le-Petross HT, et al. Identification and resection of clipped node decreases the false-negative rate of sentinel lymph node surgery in patients presenting with nodepositive breast cancer (T0-T4, N1-N2) who receive neoadjuvant chemotherapy: results from ACOSOG Z1071 (Alliance). Ann Surg. 2016;263(5):802-807.

• Arterial Anatomy of the Breast – A Practical Summary for Breast Surgeons
  • Understanding the arterial supply of the breast is essential for:
    • Oncologic resections
    • Reconstructive planning
    • Oncoplastic surgery
    • Complication avoidance
  • The breast receives a rich, redundant blood supply primarily from branches of the:
    • Subclavian and axillary arterial systems:
      • Which explains its generally good healing capacity:
        • But also the risk of bleeding if anatomy is not respected
• Primary Arterial Sources:
  • Internal Mammary (Internal Thoracic) Artery:
    • Most important medial blood supply to the breast
    • Arises from the:
      • Subclavian artery
    • Gives rise to anterior intercostal perforators, especially:
      • 2nd to 4th intercostal perforators:
        • Dominant contributors
    • Supplies:
      • Medial breast
      • Retroareolar complex
    • Key surgical relevance:
      • Critical during medial lumpectomies
      • Important for nipple-areolar complex (NAC) viability
      • Used as recipient vessels in free flap breast reconstruction
  • Lateral Thoracic Artery:
    • Branch of the axillary artery
    • Runs along the lateral chest wall
    • Supplies:
      • Lateral breast
      • Skin and glandular tissue
    • Key surgical relevance:
      • At risk during axillary dissection
      • Important contributor in lateral oncoplastic flaps
  • Thoracoacromial Artery (Pectoral Branch):
    • Branch of the axillary artery
      Supplies:
      • Upper outer quadrant
      • Pectoralis major muscle
    • Key surgical relevance:
      • Important during subpectoral dissection:
      • Preservation helps reduce skin flap ischemia
  • Posterior Intercostal Arteries:
    • Arise directly from the thoracic aorta
    • Provide deep perforating branches
    • Supply:
      • Deep parenchyma
      • Chest wall interface
    • Key surgical relevance:
      • Contribute to deep tissue perfusion
      • Source of bleeding during deep resections
• Perforator System and Anastomoses:
  • The breast has an extensive subdermal and intraparenchymal anastomotic network
  • Major perforators:
    • Medial (internal mammary)
    • Lateral (lateral thoracic)
  • Clinical implications:
    • Explains tolerance of wide local excisions
    • Allows for oncoplastic rearrangements
    • Supports skin- and nipple-sparing mastectomy when flaps are well designed
• Surgical Implications for Breast Surgeons:
  • Breast-Conserving Surgery:
    • Medial tumors:
      • Respect internal mammary perforators
    • Lateral tumors:
      • Anticipate supply from lateral thoracic artery
  • Mastectomy (Skin- or Nipple-Sparing):
    • Preserve:
      • Subdermal plexus
      • Medial perforators
    • Excessive cautery near the NAC increases ischemia risk
  • Oncoplastic Surgery:
    • Knowledge of arterial territories guides:
      • Pedicle choice
      • Flap orientation
      • Central and medial pedicles rely heavily on internal mammary perforators
  • Reconstruction:
    • Internal mammary vessels are preferred recipient vessels for free flaps
    • Axillary system preservation is important in implant-based reconstruction
• Key Take-Home Points:
  • Breast arterial supply is dual and redundant, centered on:
    • Internal mammary system (medial dominance)
    • Axillary system (lateral dominance)
    • 2nd to 4th internal mammary perforators are the most critical vessels
    • Surgical planning should always consider vascular territories, especially in:
      • Re-operations
      • Radiation-treated breasts
      • Large resections or complex oncoplastic cases
• References:
  • Arterial Anatomy of the Breast
    • Cunningham L.The anatomy of the arteries and veins of the breast.
      J Surg Oncol. 1977;9(1):71–85.
      → Classic anatomic description of breast vascular supply.
    • Salmon RJ. Vascularization of the breast and implications for surgery.
      Surg Clin North Am. 1990;70(4):877–885.
      → Foundational surgical anatomy review.
    • Hall-Findlay EJ. Breast anatomy and vascular supply.
      Clin Plast Surg. 2002;29(3):371–384.
      → Highly cited reference for oncoplastic and reconstructive surgery.
    • Sappey M. Traité d’Anatomie Descriptive. Paris: Delahaye; 1874.
      → Early detailed descriptions of breast perforators (historical reference).
    • Taylor GI, Palmer JH. The vascular territories (angiosomes) of the body.
      Br J Plast Surg. 1987;40(2):113–141.
      → Angiosome concept applied to breast perfusion and flap design.
  • Internal Mammary & Perforator Anatomy:
    • Cormack GC, Lamberty BG. The arterial anatomy of skin flaps.
      Edinburgh: Churchill Livingstone; 1994.
      → Describes internal mammary perforators relevant to breast surgery.
    • Saint-Cyr M, Wong C, Schaverien M, et al. Perforator flaps: anatomy, technique, and clinical applications. Plast Reconstr Surg. 2009;124(1 Suppl):e1–e17.
      → Detailed perforator anatomy with relevance to NAC perfusion.
    • Hamdi M, Van Landuyt K, Monstrey S, Blondeel P. Pedicled perforator flaps in breast reconstruction. Semin Plast Surg. 2006;20(2):73–83.
  • Surgical & Oncoplastic Relevance:
    • Losken A, Hamdi M. Partial breast reconstruction: current perspectives. Plast Reconstr Surg. 2009;124(3):722–736.
      → Links vascular anatomy to oncoplastic pedicle choice.
    • Clough KB, Kaufman GJ, Nos C, Buccimazza I, Sarfati IM. Improving breast cancer surgery: a classification and quadrant-based approach. Plast Reconstr Surg. 2010;125(2):418–428.
    • Mast BA. Breast reduction and mastopexy: pedicle selection and vascular considerations. Clin Plast Surg. 1996;23(3):567–576.
  • Nipple–Areolar Complex (NAC) Perfusion
    • van Deventer PV, Graewe FR. Blood supply of the nipple–areolar complex. Plast Reconstr Surg. 1984;74(4):499–504.
    • Russo V, Della Corte A, et al. Nipple–areola complex vascular anatomy and surgical implications. Aesthetic Plast Surg. 2017;41(2):267–274.
  • Reconstruction-Focused References:
    • Blondeel PN, Morris SF, Hallock GG, Neligan PC. Perforator Flaps: Anatomy, Technique, and Clinical Applications. St. Louis: Quality Medical Publishing; 2006.
  • Nahabedian MY. Breast reconstruction and internal mammary vessels.
    Plast Reconstr Surg. 2012;130(4):883–891.
    

• What was the primary research question of the INSEMA trial?
  • Answer:
    • To determine whether sentinel lymph node biopsy (SLNB) can be safely omitted in patients with clinically node-negative early-stage breast cancer undergoing breast-conserving surgery and whole breast radiation, without compromising invasive disease-free survival (iDFS)
• What type of study was this, and how was it designed?
  • Answer:
    • It was a prospective, randomized, multicenter, non-inferiority trial conducted in Germany and Austria
    • Patients were randomized in a 4:1 ratio to no SLNB vs. SLNB
• What were the eligibility criteria for patients to be included in the trial?
  • Answer:
    • Female patients
    • Clinically node-negative (cN0) invasive breast cancer
    • Tumor size cT1 to cT2 (≤ 5 cm)
    • Candidates for breast-conserving surgery and whole-breast irradiation
    • No prior axillary surgery, neoadjuvant therapy, or mastectomy
• What was the primary endpoint, and what was the non-inferiority margin?
  • Answer:
    • Primary endpoint:
      • 5-year invasive disease-free survival (iDFS)
    • Non-inferiority margin:
      • Hazard Ratio upper limit of 1.271 and ≥ 85% iDFS in the no-SLNB arm
• What were the main results regarding iDFS
  • Answer:
    • iDFS: 91.9% (no-SLNB) vs. 91.7% (SLNB)
    • HR: 0.91 (95% CI, 0.73–1.14) → Non-inferiority was met
• Was there a difference in overall survival (OS)
  • Answer:
    • Yes, but it favored no-SLNB slightly:
      • 5-year OS: 98.2% (no-SLNB) vs. 96.9% (SLNB):
        • Difference was not statistically significant
• What was the axillary recurrence rate in both groups?
  • Answer:
    • No-SLNB: 1.0%
    • SLNB: 0.3%
      • While slightly higher in the no-SLNB group:
        • Both rates were very low and clinically acceptable
• What secondary outcomes were assessed?
  • Answer:
    • Lymphedema incidence
    • Arm / shoulder function and pain
    • Quality of life
      • All significantly favored the no-SLNB group
• What are the main clinical implications of this study?
  • Answer:
    • In selected low-risk patients:
      • SLNB may be safely omitted:
        • Reducing surgical morbidity and improving quality of life without compromising survival
• Which subgroup of patients benefits most from SLNB omission based on this trial?
  • Answer:
    • Women ≥ 50 years old with T1, grade 1 to grade 2, hormone receptor-positive, HER2-negative tumors undergoing lumpectomy with whole breast radiation
• Can we apply the findings of this trial to patients undergoing mastectomy or partial-breast irradiation?
  • Answer:
    • No:
      • Those patients were excluded, so the results cannot be extrapolated to those scenarios
• How might omitting SLNB affect adjuvant therapy decisions?
  • Answer:
    • Without nodal staging, decisions about chemotherapy or genomic testing might become more challenging:
      • Multidisciplinary evaluation is essential
• How do these findings compare to axillary de-escalation trends seen in trials like ACOSOG Z0011 or SOUND?
  • Answer:
    • Similar direction:
      • All support less axillary surgery in low-risk, clinically node-negative patients
    • INSEMA takes it a step further by testing omission of SLNB itself
• What are some limitations of the INSEMA trial
  • Answer:
    • Limited generalizability:
      • Mostly postmenopausal, low-risk tumors
    • Exclusion of higher-risk patients:
      • HER2+, triple-negative, T2 > 3 cm
    • Lack of data in mastectomy or neoadjuvant settings
• If one of your patients meets criteria from this trial, how would you counsel them on omitting SLNB?
  • Answer:
    • Explain that in select low-risk early-stage breast cancer, omitting SLNB does not affect survival, reduces the risk of complications like lymphedema, and improves quality of life:
      • However, thorough discussion with oncology and radiation teams is important to individualize care

• Neoadjuvant chemotherapy (NAC):
  • Refers to the delivery of systemic treatment prior to surgery
• Preoperative chemotherapy:
  • Was initially utilized in women with locally advanced or inflammatory cancers:
    • To improve operability
• Among women with early-stage breast cancers, the NSABP B-18 and B-27 randomized clinical trials:
  • Demonstrated no difference in disease-specific or overall survival:
    • Between those who received neoadjuvant versus adjuvant chemotherapy
  • Neoadjuvant chemotherapy improved rates of breast conservation:
    • 68% versus 60%
  • More recent observational data:
    • Have demonstrated no increased risk in surgical complications among women who underwent neoadjuvant chemotherapy
• NAC has more recently been used to:
  • Downstage the axilla in patients with biopsy proven lymph node involvement with hopes to avoid completion lymphadenectomy and decrease the risk of lymphedema. Additionally, NAC has been used in women with operable breast cancers to theoretically treat micrometastatic disease prior to local therapy and to allow assessment of the in vivo tumor response to certain chemotherapy regimens.
• Notably, results from the Early Breast Cancer Trialists’ Collaborative Group (EBCTCG) meta-analysis³ included patient-level data from 4,756 women enrolled in clinical trials 1983-2002; results demonstrated a higher risk of in-breast recurrence after neoadjuvant chemotherapy. At 15 years, women treated with NAC had a 21% risk of local recurrence (vs. 16% in the surgery-first patients). This was attributed to a higher rate of breast conservation, but with no difference in distant recurrence or breast cancer-specific overall survival.³
• References
• 1. Fisher B, Bryant J, Wolmark N, Mamounas E, Brown A, Fisher ER, et al. Effect of preoperative chemotherapy on the outcome of women with operable breast cancer. J Clin Oncol. 1998;16(8): 2672-2685.
• 2. Boughey J, Peintinger F, Meric-Bernstam F, Perry AC, Hunt KK, Babiera GV, et al. Impact of preoperative versus postoperative chemotherapy on the extent and number of surgical procedures in patients treated in randomized clinical trials for breast cancer. Ann Surg. 2006;244(3):464-470.
• 3. Early Breast Cancer Trialists’ Collaborative Group (EBCTCG). Long-term outcomes for neoadjuvant versus adjuvant chemotherapy in early breast cancer: meta-analysis of individual patient data from ten randomized trials. Lancet Oncol. 2018;19(1):27-39.