"Phyllodes" - from Greek Phyllon = 'leaf'.
A cousin of the fibroadenoma; nonepithelial.
AKA cystosarcoma phyllodes (old term,
D E A B M I M
Most common neoplasm of nonepithelial origin of the breast.
- estimated at between 2-4% as common as fibroadenomas.
Estimated at 2.1 / million for malignant
Median is 45yrs (R&A)
- ie 20 years later than average fibroadenoma patient.
- and same age as cancer group.
- very few are younger than 25 years, but can occur in adolescents.
--> in women over 35 with a rapidly enlarging ?fibroadenoma,
Are exclusive to the female breast.
D E A B M I M
Non-epithelial stromal tumours - see below.
D E A B M I M
Phylloides arises from periductal stromal tissue, fibroadenomas do
A bulky tumour.
- usually sharply demarcated.
- round, freely mobile, smooth contour, firm.
- median size 4-5cm at excision; can be any size, perhaps very
When cut, gives an embossed 'leaflike' appearance.
First named 'cystosarcoma phyllodes' (1838 by Müller).
- on microscopy, cystlike spaces lined with low epithelium are often
- however sarcoma is an exaggeration, as most are believed benign.
The term 'fibroadenoma phyllodes' is again only acceptable to some
- so the simple term phyllodes
tumour is preferred (WHO recommendation).
How does it differ from a
Two key features (R&A):
i) stromal hypercellularity.
- can be difficult to distinguish from hypercellular fibroadenomas
possible, if not its academic anyway usually).
ii) presence of benign glandular elements integral in the neoplasm.
It is the amount and appearance of the stromal elements that
whether it be called a fibroadenoma or phylloides.
- and what its chances of malignacy are.
A description of malignant potential is given based on stromal
- 25% = malignant
- 60% = benign
- 15% = indeterminate potential.
Risk factors of metastatic
Histological features include nuclear atypia, numerous mitoses and
of relationship between glands and stroma (stromal overgrowth).
- the latter may be the most useful (Petrek).
Multivariate retrospective analysis of histology:
- histologic type (one study)
- stromal type + presence of necrosis (one study)
- NOT to tumour size or margin status.
For benign lesions enucleated, 5-year LR of 4% reported (Sabiston).
- "20% of all phyllodes will recur if excised without margin"
Multiple reports describe "malignant transformation".
- ie recurrent tumour more aggressive histologically than the
- however this is uncommon in reality (Petrek).
The cytologically malignant tumours have metastatic potential.
- varies from 3-12% in various series (R&A),
- overall <5% metastasise, 20% of malignant lesions and up
to 5% of benign lesions (Sabiston).
- axillary mets are rare
Rather, most spreading systemically do so haematogenously
- commonly to lung, bone, possibly to CNS (R&A), possibly abdo
viscera, mediastinum (Sabiston).
- contain only the stromal elements histologically.
- no reports of long-term survivors --> truly sarcomas.
D E A B M I M
Almost always a rounded, painless, smooth, multinodular breast mass.
- most report continuous growth
- others rapid growth in a previously stable longstanding nodule.
Overlying skin almost never attached.
- but may be shiny and stretched.
- rarely ulcerates, when due to ischaemia however, rather than
Nipple will not be retracted or invaded.
May be detected in up to 20%, but as above is rarely due to
- rather suspect necrotic or infected tumour mass.
Impossible to distinguish clinically, radiologically, or even via
triple assessment from a fibroadenoma.
Consider this diagnosis if:
- larger size
- history of rapid growth
- patients >35
But not exclusive to these groups.
The diagnosis is usually made from excision biopsy.
D E A
Cytology is inaccurate comparing low-grade phyllodes from
One series of core biopsy showed true +ve rate of 50% (Sabiston).
Round densities, smooth borders.
Usually indistinguishable from fibroadenoma.
- irregular margins may suggest local invasion.
Discrete structure with cystic spaces.
Again, often mistaken for fibroadenoma.
D E A
Excision to 1cm negative margins is advocated (where phylloides is
known) to lower LR risk (Sabiston).
- LR is usually seen within a few years of surgery.
- inversely correlated with width of negative resection margin.
- do not simply enucleate the lesion --> unacceptable LR rate
Routine mastectomy and axillary clearance can be avoided (see
- however removal of low nodes, especially if palpable cannot be
What if I thought it was a
fibroadenoma at the time, and simply enucleated it?
Most patients should undergo reexcision within 4 weeks.
What if the histology returns a
tumour with strong malignant potential?
Breast preservation has been accomplished with satisfactory
Usually treated with total mastectomy.
However, can still be cured by adequate WLE (R&A).
- take 2-3cm margins.
- more aggressive Rx to confront possibility of malignant
is ill-advised as this is rare (see above).
No, tend not to spread via LNs
Palliative Treatments for
Optimal therapy not defined (Sabiston).
- no sustained remission from any treatment.
- good published data is lacking.
Most used = cyclophosphamide- or doxyrubacin- containing combos.
- ie as for sarcomas, not breast cancers.
Several used cisplatin and etoposide combination chemo.
Radiation to symptomatic mets may help.
Most contain estrogen and progesterone receptors
- palliation with hormone manipulation has not been extensively
Distant pulmonary single mets may be excised with possibility of
D E A
Rosai & Ackerman 9th.
Petrek JE. Phyllodes Tumour.
in Diseases of the Breast.