Phyllodes Tumours

What are Phyllodes Tumours?

Phyllodes tumours, also known as cystosarcoma phyllodes, are uncommon fibroepithelial tumours of the breast that can behave benignly or malignantly. Unlike the more common types of breast cancer that primarily arise from the epithelial cells lining the milk ducts or glands, phyllodes tumours mainly involve the stromal or connective tissue of the breast. A leaf-like structure typically characterises these tumours and can grow quite large and quickly, distinguishing them from other breast tumours.

How Do Phyllodes Tumours Impact Your Anatomy and Health?

The primary impact of phyllodes tumours on anatomy and health depends on their size, growth rate, and whether they are benign, borderline, or malignant:

Size and Growth: Phyllodes tumours can grow rapidly and often become quite large, potentially distorting the shape of the breast and causing discomfort or pain.
Malignant Potential: While most phyllodes tumours are benign, a small percentage can be malignant, potentially spreading to other parts of the body, particularly the lungs. Malignant phyllodes tumours can be aggressive and may recur even after surgical removal.
Surgical Treatment: Treatment typically involves surgery to remove the tumour. In cases where the tumour is large or recurrent, this might lead to significant changes in breast appearance and reconstructive surgery might be considered.

Risk Factors for Phyllodes Tumours

Phyllodes tumours are most commonly found in women in their 40s but can occur at any age. They are very rare in men. Factors that might increase the risk of developing phyllodes tumours are not well understood due to their rarity. Still, there does not seem to be a strong link with the typical risk factors associated with more common types of breast cancer, such as family history.

Causes of Phyllodes Tumours

The exact cause of phyllodes tumours is not known. They arise from the periductal stromal cells of the breast, which are the connective tissue cells surrounding the breast ducts. There is no established connection between phyllodes tumours and genetic or lifestyle factors that typically influence the risk of other breast cancers. Research is ongoing to better understand the molecular and genetic factors that may contribute to the development of these tumours.

Symptoms of Phyllodes Tumours

The symptoms of Phyllodes tumours can be quite subtle and are often similar to those of more common breast lumps. Key symptoms include:

Palpable Lump: The most common symptom is a palpable lump in the breast that grows rapidly. This lump is usually painless but can become uncomfortable if it grows large enough to stretch the skin or distort breast tissue.
Change in Breast Shape: As the tumour grows, it may cause visible changes in the shape or size of the breast.
Skin Changes: In some cases, especially if the tumour grows rapidly, there might be skin changes over the lump, such as redness or dimpling.

Types of Phyllodes Tumours

Phyllodes tumours are categorised based on their histological appearance and the likelihood of aggressive behaviour:

Benign: These tumours have well-defined borders and lack the cellular characteristics that suggest aggressive behaviour. They are the least likely to recur after removal and have a very low risk of spreading.
Borderline: These tumours have features that are between benign and malignant. They may have some cellular abnormalities and are at a higher risk of recurrence.
Malignant: These tumours show signs of aggressive behaviour, including the potential to metastasise (spread to other parts of the body). They often have poorly defined borders, increased cell division rates, and may infiltrate surrounding tissues.

Stages of Phyllodes Tumours

Unlike more common forms of breast cancer, Phyllodes tumours do not follow the typical TNM staging system (Tumour, Node, Metastasis). Instead, they are classified more simply based on their histological features (as benign, borderline, or malignant) and the presence or absence of metastases:

Local: The tumour is confined to the breast. Most Phyllode tumours fall into this category when diagnosed.
Metastatic: This stage is applicable only for malignant Phyllodes tumours. It indicates that the tumour has spread beyond the breast to other body parts, most commonly the lungs.

Diagnosis of Phyllodes Tumours

Clinical Examination: A doctor will physically examine the breasts to check for lumps or other unusual changes.
Imaging Tests: Mammography and ultrasound are commonly used to evaluate the lump. These imaging tests can help distinguish between a Phyllodes tumour and other breast tumours based on their appearance, but they often cannot definitively diagnose a Phyllodes tumour.
Biopsy: A biopsy is crucial for diagnosis. This involves removing a tissue sample from the lump, which is then examined under a microscope. Core needle biopsy is commonly used, but in some cases, an excisional biopsy (removal of the entire lump) may be necessary because Phyllodes tumours can be difficult to differentiate from other fibroepithelial lesions like fibroadenomas.

Treatment of Phyllodes Tumours

The treatment for Phyllodes tumours primarily involves surgery, and the approach depends on the type of tumour:

Surgical Removal: The main treatment is surgical excision with a margin of healthy tissue to reduce the risk of recurrence. Depending on the size and location of the tumour and whether it has recurred, the extent of surgery may vary from lumpectomy (removing just the tumour and a small margin of surrounding tissue) to mastectomy (removing the entire breast).
Radiation Therapy: For malignant Phyllodes tumours, especially those that are large or have recurred, radiation therapy may be used after surgery to decrease the risk of another recurrence.
Chemotherapy: While less common, chemotherapy may be considered in cases where the Phyllodes tumour is malignant and has spread to other parts of the body.

What if Phyllodes Tumours are Untreated?

Leaving Phyllodes tumours untreated can lead to several complications, particularly if the tumour is malignant:

Rapid Growth and Discomfort: Phyllodes tumours can grow quickly, causing discomfort or pain and significant changes in the appearance of the breast.
Recurrence: Even after initial growth, Phyllodes tumours can recur, especially if they are not completely removed or if they are borderline or malignant.
Metastasis: In rare cases, malignant Phyllodes tumours can metastasise to other body parts, which can be life-threatening and require more intensive treatment.

Prompt and effective treatment of Phyllodes tumours is crucial to manage the disease and prevent these complications. Regular monitoring and follow-up are also important, especially for women who have had borderline or malignant Phyllodes tumours, to detect any recurrence early.