What is breast-conserving surgery?
Also known as (some of them wrongly) lumpectomy, sector resection, partial mastectomy or segmental resection, this operation involves excising the malignant lesion with margins free of tumour cells.
Eligibility criteria: who is it suitable for?
The indication for conservative treatment is made in the multidisciplinary oncology board (Tumor Board), carefully assessing:
- Tumour-to-breast volume ratio: It is essential that enough tissue remains after the tumour is removed for an acceptable aesthetic result.
- Unifocality of the lesion: A single tumour focus (or nearby foci that can be removed in the same specimen).
- Ability to give postoperative radiotherapy: Radiotherapy to the remaining breast is a mandatory component of breast-conserving treatment.
- Response to neoadjuvant treatment: In patients whose tumours are initially large, chemotherapy given before surgery can reduce the size of the lesion, making it possible to conserve a breast that would otherwise have needed a mastectomy.
When is breast-conserving surgery NOT indicated?
- Multiple tumour foci in different quadrants (multicentric disease)
- Extensive, diffuse malignant microcalcifications
- An unfavourable ratio between a large tumour and a small breast
- Absolute contraindications to radiotherapy
- Impossibility of obtaining clear resection margins after repeat operations
Resection and maintaining the shape of the breast
The surgical approach is adapted to the size of the defect created:
Conservative resection
Applied to small tumours relative to the volume of the breast. The remaining space is closed by simply mobilising the adjacent glandular tissue, without visible deformity.
Resection with oncoplastic remodelling
If the tumour requires a wider excision area or lies in aesthetically difficult areas, oncoplastic techniques (similar to breast lift or reduction techniques) are used to prevent marked asymmetry of the breast.
Assessing the axillary lymph nodes
In most cases of invasive breast cancer, a sentinel lymph node biopsy (the first lymph node station to which lymph from the breast drains) is performed at the same time as the breast surgery. If extensive nodal metastases are confirmed, lymphadenectomy is used.
The course of the operation: from diagnosis to recovery
Investigations and confirmation
We review the imaging file (ultrasound, mammography, breast MRI if needed) and the histopathological result of the breast biopsy.
Localisation of the lesion (if needed)
For small tumours that cannot be felt or are found only on imaging, shortly before the operation a wire or a special marker is placed under ultrasound or radiological guidance to locate the lesion.
The operation
It is performed under general anaesthesia. The surgeon removes the tumour with a macroscopic margin of healthy tissue and excises the sentinel lymph node(s).
Final histopathological examination
The excised specimen is examined carefully under the microscope to measure the surgical margins precisely. The modern standard concept is “no ink on tumor” (no malignant cells at the inked margins).
Adjuvant (postoperative) treatments
Radiotherapy (a mandatory standard after conservative surgery), systemic treatment (hormone therapy, chemotherapy, biological targeted therapies or immunotherapy), as recommended by the medical oncologist.
Possible risks and complications
Breast-conserving surgery is a safe procedure, with a low rate of complications:
- General/local: A seroma (collection of lymphatic fluid), haematoma, local infection or delayed healing.
- Axillary: With sentinel node biopsy the risk of complications is low; with complete axillary clearance (lymphadenectomy), local numbness, reduced shoulder mobility and lymphoedema of the arm (swelling of the upper limb) can occur.
Post-operative recovery
- Hospital stay
- Usually an operation with a short hospital stay (1–3 days).
- Comfort and mobility
- Post-operative pain is mild to moderate and is controlled effectively with common painkillers. Gradual resumption of gentle arm movements from the first days is recommended.
- Support
- Wearing a supportive bra is recommended in the first weeks.
- Restrictions
- Avoid heavy lifting and strenuous exercise for 3–4 weeks.
Warning signs: when to contact your doctor
Contact the surgical team if you have:
- Fever (above 38°C) or chills
- Sudden, painful and marked swelling of the breast or armpit
- Persistent redness, local warmth or discharge from the wound
- Severe pain that does not respond to prescribed medication
- Active bleeding through the dressing
For any major emergency, call the 112 emergency service.
Frequently asked questions
Does mastectomy offer a higher chance of cure than breast-conserving surgery?
No. International guidelines confirm that, for early-stage disease and eligible patients, breast-conserving surgery combined with radiotherapy offers the same overall survival rate as mastectomy. Mastectomy does not guarantee better survival if the disease can be treated conservatively in complete safety.
Is radiotherapy mandatory if the whole tumour has been removed?
Yes. Even if the margins are free of tumour cells under the microscope, radiotherapy to the remaining breast destroys any residual microscopic cells and dramatically reduces the risk of local recurrence. The only exceptions are rare and strictly selected according to international clinical criteria (advanced age, very small tumours, positive hormone receptors, very low risk).
What will the breast look like after the operation?
In most cases where the resected volume is proportionate to the breast, the appearance and contour remain natural, and the scar becomes discreet over time. If a more generous excision is needed, the oncoplastic techniques used during the same operation prevent unsightly asymmetries.
What happens if the resection margins are not “clear”?
This situation is discussed openly with each patient. Tumour cells at the edge of the specimen indicate the need for a second operation (re-excision) to clear the tumour bed. Conversion to mastectomy (with the possibility of reconstruction) is considered only when re-excision cannot ensure clear margins or would severely alter the appearance of the breast.
Want to talk about your situation?
Every case is different. At the consultation we go through the options together.
Medically reviewed by Dr. Răzvan Andrei. Last updated: 1 October 2026.