From the Guidelines
Surgical re-excision with wide margins is the primary treatment approach for recurrent malignant phyllodes tumors, with consideration of adjuvant radiation therapy to reduce the risk of local recurrence, as recommended by the most recent guidelines 1.
Treatment Approach
The management of recurrent malignant phyllodes tumors involves a multidisciplinary approach, with surgery being the primary treatment modality.
- Surgical re-excision with wide margins (at least 1 cm) is recommended to ensure complete removal of the tumor.
- Mastectomy may be necessary if the recurrence is extensive or if breast-conserving surgery would yield poor cosmetic results.
- Adjuvant radiation therapy is often recommended, particularly in cases with close or positive margins, large tumors, or multifocal disease, to reduce the risk of local recurrence 1.
Radiation Therapy
Radiation therapy can be considered in cases where additional recurrence would create significant morbidity, such as chest wall recurrence after salvage mastectomy, following the same principles that are applied to the treatment of soft tissue sarcoma 2.
- Radiation therapy is typically delivered at doses of 50-60 Gy over 5-6 weeks.
Systemic Chemotherapy
Systemic chemotherapy may be considered for metastatic disease, with regimens similar to those used for soft tissue sarcomas, such as doxorubicin and ifosfamide or gemcitabine and docetaxel.
Surveillance
Close surveillance is essential after treatment, with physical examinations every 3-6 months for the first 2 years, then every 6-12 months thereafter, along with annual mammography or breast MRI.
Recurrence Rates
Malignant phyllodes tumors tend to recur because of their rapid growth and infiltrative nature, with recurrence rates of 20-40% 1. The stromal component of these tumors is responsible for their malignant behavior, and recurrences often show increased cellular atypia and mitotic activity compared to the original tumor. It is essential to refer breast sarcomas and phyllodes tumors, of borderline and malignant subtypes, to specialist sarcoma centers for pathology review and MDT discussion to ensure optimal management and improve clinical outcomes 1.
From the Research
Recurrence of Phyllodes Malignant Tumor
- The recurrence of phyllodes malignant tumors is a significant concern, with studies indicating that the risk of local recurrence is higher in borderline and malignant tumors compared to benign tumors 3, 4, 5, 6.
- A study published in 2021 found that adjuvant radiation therapy significantly improved local recurrence-free survival (LRFS) in patients with borderline and malignant phyllodes tumors, with a 5-year LRFS of 90% in the radiation therapy group compared to 42% in the no radiation therapy group 3.
- Another study published in 2021 reported a case of a locally recurrent and metastatic malignant phyllodes tumor that was successfully treated with accelerated radiotherapy and chemotherapy, resulting in complete regression of lung metastases and no evidence of local recurrence 7.
- The role of surgical margins in preventing recurrence is also important, with studies suggesting that a margin of ≥1 cm is associated with excellent local control in benign and borderline tumors, while narrower margins may be acceptable in benign tumors 4, 5, 6.
- A retrospective analysis of 150 phyllodes tumors found that 10 of 11 locally recurrent tumors had a positive margin or ≤1 mm margin at initial surgery, highlighting the importance of adequate surgical margins in preventing recurrence 6.
- The predictors of recurrence in phyllodes tumors include histopathological grade, surgical margins, and tumor size, with borderline and malignant tumors having a higher risk of recurrence compared to benign tumors 4, 5, 6.