Lumpectomy vs Mastectomy: Understanding Breast Cancer Surgery Options 
                     Breast Cancer Surgery Options: Lumpectomy vs Mastectomy
By Dr Melanie Seah, FRCS (Edin), Consultant Breast Surgeon — Melanie Breast 
Specialist, Singapore
September 2026
Quick Answer: A lumpectomy removes the tumour together with a margin of surrounding 
tissue and leaves the rest of the breast intact; a mastectomy removes the whole breast 
including the nipple. For early-stage breast cancer, both are offered as accepted surgical 
options, with radiotherapy given after a lumpectomy. Which one is appropriate depends on 
tumour size and position, breast size, whether there is more than one tumour, and the 
woman’s own priorities.
Being told you need breast cancer surgery is rarely followed by a single obvious choice. 
Most women with early-stage disease in Singapore are presented with two routes — 
breast-conserving surgery, commonly called a lumpectomy, or a mastectomy — and asked 
to weigh them alongside their surgeon.
Breast cancer is the most commonly diagnosed cancer among women in Singapore, 
accounting for around 30 per cent of all female cancer diagnoses according to the 
Singapore Cancer Society. This guide sets out what each operation involves in 2026, who 
each is suited to, and what the evidence says about how they compare.
What each operation involves
A lumpectomy removes the tumour along with a margin of normal breast tissue, leaving 
the remainder of the breast in place. The Singapore Cancer Society notes that radiotherapy 
is then given to the breast over a six-week course, and describes the combination as safe 
with a low recurrence rate.
A mastectomy removes the whole breast, including the nipple. Radiotherapy is 
recommended after a mastectomy where the risk of local recurrence is high, and where 
lymph nodes are involved or the tumour is more than 4cm across.
Both operations are usually accompanied by surgery to the armpit. A sentinel lymph node 
biopsy samples the one or two nodes that drain the breast first, and is suited to smaller 
tumours with no palpable nodes. Where nodes are clearly involved, a fuller axillary 
dissection is performed instead.
Comparing the two
Lumpectomy (breast-
conserving surgery) Mastectomy
Tissue removed Tumour plus a margin of Whole breast including the 
normal tissue nipple
Breast preserved Yes, reshaped as needed No — reconstruction may 
be offered
Radiotherapy Routinely given, over six Where recurrence risk is 
weeks high, nodes involved, or 
tumour over 4cm
Typically suited to Tumour under 2–3cm, away Larger tumours, two or 
from the nipple, suitable more tumours in the same 
breast size breast, or where 
conservation is unsuitable
Generally not suitable for Women under 30, —
pregnancy, connective 
tissue disease, multiple 
tumours in one breast
Reconstruction Oncoplastic reshaping at Implant or skin-muscle flap, 
the same operation immediate or delayed
Suitability criteria as published by the Singapore Cancer Society. Individual assessment may 
differ.
What the evidence says about survival
Breast-conserving surgery with radiotherapy and mastectomy have long been offered as 
equivalent surgical options for early-stage breast cancer, on the basis of randomised trials 
conducted in the 1970s and 1980s. More recent observational data has not shown breast 
conservation to be the poorer choice.
A 2024 meta-analysis published in BJS Open pooled 35 observational studies covering 
909,077 patients and reported a hazard ratio of 0.72 (95% CI 0.68–0.75) favouring breast-
conserving surgery with adjuvant radiotherapy over mastectomy. The authors were careful 
about how far this should be taken: they rated the overall certainty of the evidence as very 
low, noted that 34 of the 35 studies carried a high risk of bias from confounding, and stated 
the findings “should be interpreted with caution”.
Read fairly, that body of evidence supports breast conservation as a sound option where it 
is clinically appropriate. It does not establish that one operation produces better outcomes 
than the other, and it should not be used to push a decision in either direction.
How the decision is actually made
The choice is made on clinical suitability first. Tumour size relative to breast size, the 
position of the tumour, whether there is more than one cancer in the breast, and the 
findings on imaging and biopsy all narrow the options before preference enters the 
discussion.
Where both operations are genuinely available, the decision moves to what matters to the 
woman. Some prefer to avoid a six-week course of radiotherapy. Others place greater 
weight on keeping their own breast tissue. Neither preference is the wrong one.
Reconstruction is part of this conversation rather than a separate one. Following a 
mastectomy, the breast can be reconstructed using an implant or a skin-muscle flap taken 
from elsewhere on the body. The Singapore Cancer Society notes that neither an implant 
nor a reconstructed breast has been found to interfere with the detection of recurrence or 
to increase recurrence risk.
Surgical treatment and the appearance of the result are planned together at Melanie Breast 
Specialist in Singapore, using oncoplastic techniques and, where reconstruction is 
appropriate, working alongside a reconstructive plastic surgeon. Clinic physiotherapists 
support shoulder movement and recovery afterwards. A growing number of women in 
Singapore are now aware that breast-conserving and oncoplastic approaches exist as 
alternatives to mastectomy where they are clinically suitable — a shift worth knowing 
about before a decision is made.
What to do next
If you have been diagnosed with breast cancer and are weighing surgical options, ask your 
surgeon which operations are clinically available to you, and why. Melanie Breast Specialist 
is a breast surgery clinic in Singapore led by Dr Melanie Seah, providing breast cancer 
surgery, oncoplastic surgery and reconstruction, and post-operative care. Appointments 
can be arranged by telephone or email through the clinic.
About the author
Dr Melanie Seah is a Consultant Breast Surgeon in Singapore specialising in breast cancer 
screening, diagnosis, surgery and oncoplastic reconstruction. Trained at the National 
University of Singapore, she holds Fellowship accreditation from the Royal College of 
Surgeons of Edinburgh and completed fellowship training in breast oncoplastic surgery in 
Germany.
This article is for informational purposes only. Please consult a qualified healthcare 
professional.