Overview
Definition:
Nipple-areola-sparing mastectomy (NASM) is a surgical procedure where the entire breast tissue is removed, but the nipple-areola complex (NAC) is preserved
This technique aims to improve cosmetic outcomes and patient satisfaction by maintaining the natural appearance of the breast mound while achieving oncologic safety in select patients.
Epidemiology:
NASM is increasingly being considered for patients with early-stage breast cancer or for prophylactic mastectomy in high-risk individuals
Its application varies based on tumor location, size, and patient-specific factors
Exact epidemiological data on NASM rates are still evolving, but it represents a significant advancement in breast cancer surgery.
Clinical Significance:
For DNB and NEET SS aspirants, understanding NASM is crucial as it signifies a shift towards oncoplastic surgery principles
It demands a nuanced approach to patient selection, surgical technique, and multidisciplinary care to balance oncologic control with aesthetic preservation, impacting patient quality of life and surgical decision-making.
Indications
Oncologic Indications:
Early-stage breast cancer, particularly tumors located in the peripheral breast tissue with no nipple involvement
DCIS (Ductal Carcinoma In Situ) limited to the subareolar region can also be considered
Microcalcifications without a palpable mass or architectural distortion are key indicators.
Prophylactic Indications:
High-risk individuals with genetic mutations (e.g., BRCA1, BRCA2) or strong family history of breast cancer, where the risk of developing cancer in the preserved NAC is deemed acceptable after thorough counseling.
Patient Selection Criteria:
Absence of tumor within 2 cm of the nipple-areolar complex on imaging and clinical examination
No Paget's disease of the nipple
No inflammatory breast cancer
Adequate breast volume to achieve a satisfactory aesthetic result post-reconstruction
Patient understanding and acceptance of potential risks.
Contraindications:
Tumor involving the NAC (clinically or radiologically)
Paget's disease of the nipple
Inflammatory breast cancer
Large or ptotic breasts where NAC viability is compromised
Active smoking or other conditions affecting wound healing
Patient preference for complete NAC removal.
Preoperative Preparation
Patient Counseling:
Thorough discussion of risks and benefits, including potential for NAC necrosis, loss of sensation, inability to breastfeed, and risk of recurrence
Detailed explanation of reconstruction options (e.g., immediate implant-based reconstruction, autologous tissue reconstruction, or delayed reconstruction).
Imaging And Biopsy:
Comprehensive mammography, ultrasound, and MRI to accurately assess tumor extent and rule out multifocal or multicentric disease
Biopsy confirmation of malignancy or precancerous lesions is mandatory.
Surgical Planning:
Marking of incision lines (e.g., inframammary fold, periareolar) and planned skin flaps
Assessment of NAC vascularity and planning for meticulous dissection to preserve its blood supply
Coordination with reconstructive surgeon if immediate reconstruction is planned.
Anesthesia Considerations:
General anesthesia is typically required
Anesthesia team should be aware of the extensive dissection and potential for blood loss, and the need for careful hemodynamic management.
Procedure Steps
Incision And Dissection:
A curvilinear incision is made in the inframammary fold or a periareolar incision is used, depending on the surgical approach and reconstructive plan
Thin skin flaps are meticulously raised, preserving the subdermal vascular plexus supplying the NAC
The entire breast parenchyma is dissected from the pectoralis major muscle.
Parenchymal Excision:
The breast tissue is removed in one piece, ensuring adequate margins around the tumor
The specimen is oriented for pathological examination, paying close attention to margins closest to the NAC.
Hemostasis And Drainage:
Meticulous hemostasis is achieved using electrocautery and ligation of vessels
Drains are usually placed to manage seroma formation, particularly with immediate reconstruction.
Reconstruction:
Immediate reconstruction may involve placement of tissue expanders, implants, or autologous flaps
The choice depends on patient factors, surgeon expertise, and oncologic considerations
Delayed reconstruction is performed after completion of adjuvant therapy.
Postoperative Care
Wound Management:
Dressing changes as per protocol, monitoring for signs of infection, dehiscence, or flap compromise
Gentle handling of the NAC is emphasized.
Pain Management:
Adequate analgesia is provided, often with multimodal approaches including opioids, NSAIDs, and nerve blocks
Early mobilization is encouraged.
Drain Management:
Drains are typically removed when output is less than 20-30 mL per 24 hours
Monitoring for drain site complications.
Adjuvant Therapy:
Postoperative adjuvant therapy (chemotherapy, radiotherapy, endocrine therapy, targeted therapy) is planned based on the final pathology report, tumor characteristics, and patient's overall risk profile
Radiotherapy may require specific planning to avoid excessive radiation to the preserved NAC.
Complications
Early Complications:
NAC ischemia or necrosis (partial or complete)
Hematoma or seroma formation
Wound infection or dehiscence
Flap necrosis
Pain
Seroma
Extrusion of expander.
Late Complications:
Loss of NAC sensation
Poor aesthetic outcome (e.g., asymmetry, distortion)
Asymmetry of the breast mound
Inability to breastfeed
Scarring
Implant-related issues (capsular contracture, rupture)
Risk of occult malignancy in the NAC requiring re-excision.
Prevention Strategies:
Careful patient selection
Meticulous surgical technique to preserve vascular supply to the NAC
Adequate hemostasis
Judicious use of drains
Careful flap handling
Appropriate reconstructive planning
Close postoperative monitoring.
Prognosis
Factors Affecting Prognosis:
Histological grade and subtype of breast cancer
Lymph node status
Receptor status (ER, PR, HER2)
Adequacy of surgical margins
Response to adjuvant therapy
Presence of BRCA mutations.
Oncologic Outcomes:
When performed in carefully selected patients with appropriate oncologic follow-up, NASM can achieve comparable oncologic outcomes to traditional mastectomy
The risk of NAC recurrence is low but not zero and depends heavily on preoperative assessment and tumor biology.
Aesthetic Outcomes:
Generally good, with improved body image and psychological well-being compared to standard mastectomy
However, outcomes can be variable and depend on the surgeon's skill, reconstructive technique, and individual healing patterns.
Follow Up:
Regular clinical breast examinations, mammography (for the contralateral breast and remaining chest wall if reconstructed with implant), and potentially MRI are essential
Patients should be educated on self-breast examination and aware of symptoms of recurrence.
Key Points
Exam Focus:
NASM is indicated for selected breast cancers and prophylactic settings to preserve cosmesis
Key to success is meticulous patient selection, preserving NAC vascularity during dissection, and appropriate reconstruction
Oncologic safety must never be compromised.
Clinical Pearls:
Always consider the 2 cm rule from the NAC for tumor clearance, but also rely on imaging (MRI is key) and palpation
If any doubt about NAC involvement, err on the side of caution and consider standard mastectomy or NAC excision
Communication with the pathologist regarding specimen orientation is paramount.
Common Mistakes:
Inadequate preoperative assessment leading to inappropriate patient selection
Aggressive dissection compromising NAC blood supply
Over-reliance on imaging without clinical correlation
Failure to discuss the risk of occult malignancy in the NAC
Inadequate oncologic follow-up after surgery.