Phyllodes Tumour in Singapore: A Fast-Growing Breast Lump

Written & reviewed by the BestDoctors.sg editorial team · Last updated 25 Aug 2026 · General information, not medical advice

Any new breast lump should be checked — a phyllodes tumour cannot be told apart from a fibroadenoma or from cancer by feel alone. A lump that is growing quickly should be reviewed promptly rather than watched at home.

What it is

The name comes from the Greek for “leaf-like,” reflecting the leaf-shaped growth pattern seen under the microscope. Grading into benign, borderline and malignant matters because the malignant ones grow fastest and are the most likely to spread or recur. Even a benign phyllodes behaves differently from a fibroadenoma — it can grow quickly and can come back locally after removal — which is why treatment and follow-up are taken seriously regardless of grade.

Causes and who gets it

In most cases there is no identifiable cause and nothing the woman did to bring it on. It is most commonly diagnosed in women in their 40s — broadly, women in their 30s and 40s and older, generally a decade or so older than the typical age for a fibroadenoma — and rarely occurs in younger women or, very rarely, in men. No strong lifestyle or inherited risk factors are recognised for the common benign form.

Symptoms

The classic presentation is a firm, smooth, painless breast lump that a woman often notices herself. A hallmark feature is rapid growth — the lump may enlarge noticeably over weeks to a few months, which is a key reason to seek assessment promptly. Larger tumours may stretch or shine the overlying skin, with prominent veins visible, and can distort the breast; skin ulceration is uncommon and, if present, warrants urgent review. It is usually not painful, though a large lump may feel uncomfortable from its size.

Red flags

Any new breast lump should be checked by a doctor, because a phyllodes tumour cannot be reliably told apart from a fibroadenoma, or from breast cancer, by feel alone, and a lump that is growing quickly should be reviewed promptly rather than watched at home. Other breast changes that always warrant assessment include skin dimpling or puckering, skin changes or ulceration over a lump, nipple changes or discharge, or a lump that is fixed or hard. The central safety message is that a phyllodes tumour can mimic both a benign fibroadenoma and breast cancer, so do not assume any lump is harmless without proper assessment, and remember that a minority of phyllodes tumours are malignant. A breast lump is not itself a 995 emergency, but it needs prompt specialist assessment.

How it is assessed

Triple assessment is the standard approach for any breast lump: a clinical examination, imaging (ultrasound and/or mammogram — ultrasound often first in younger women), and a tissue sample. Phyllodes is notoriously difficult to distinguish from a fibroadenoma on imaging and even on a small needle biopsy, so a core-needle biopsy is usually needed and sometimes even that cannot give a definitive answer. Because of this diagnostic overlap, doctors often recommend removing the whole lump (excisional biopsy) to get a definitive diagnosis and to grade it. Suspicion rises when a fibroadenoma-like lump is unusually large, is growing quickly, or occurs in an older-than-typical woman.

Treatment

The mainstay is surgery: complete removal of the tumour with a rim of surrounding normal tissue — a clear margin, often described as wide local excision. A clear margin matters because phyllodes tumours, including benign ones, can recur locally, and inadequate margins raise that risk; depending on tumour size relative to the breast, surgery ranges from a wide local excision to, occasionally, mastectomy for very large tumours. Lymph-node surgery is generally not needed, because phyllodes tumours rarely spread to lymph nodes, and when malignant ones spread it is typically through the bloodstream. Radiotherapy or other treatment may be considered in selected borderline or malignant cases. Regular follow-up with examination and imaging is important after surgery, because recurrence can happen even after a benign phyllodes.

Outlook and follow-up

The outlook for benign and most borderline phyllodes tumours after complete excision with a clear margin is generally very good, while malignant phyllodes carries a more guarded outlook. Because recurrence is possible, keeping to the follow-up schedule of clinical review and imaging matters, and it is worth continuing breast awareness so that any new lump — in the same area or elsewhere — is reported early. If a phyllodes tumour does recur, it is usually treated again with surgery to achieve clear margins. The reassuring overall message is that, caught and removed properly, most phyllodes tumours are managed successfully — which is precisely why acting promptly on a new or fast-growing lump is so worthwhile.

When to see a doctor

See a doctor for any new breast lump, and promptly for a lump that is enlarging quickly, so the right diagnosis can be made and, if needed, surgery with clear margins arranged in good time.

Related breast-health topics

• Fibrocystic breast changes
• Intraductal papilloma
• Breast abscess
• Galactorrhoea (milky discharge)
• Breast calcifications
• Mammary duct ectasia
• Breast self-examination
• Inverted nipple
• Fat necrosis of the breast
• Breast cancer screening
• Breast surgeons in Singapore

Sources

• American Cancer Society — Phyllodes Tumors of the Breast: cancer.org
• National Cancer Centre Singapore — Breast Cancer: nccs.com.sg
• Breast Cancer Foundation Singapore: bcf.org.sg