Effect of postoperative time for adjuvant radiotherapy in malignant phyllodes tumor: An institutional experience

Cystosarcoma phyllodes of the breast, an uncommon sarcoma found primarily in women of the age group of 35-55 years, constitutes <1% of all breast neoplasms. These tumors are resistant to chemotherapy and hormonal therapies and often recur aggressively after initial surgery. Limited research is available about the role and effectiveness of adjuvant radiotherapy in reducing recurrences.

Surgery has been the primary treatment modality to date but with high recurrence rates. The purpose of this retrospective study is to highlight the role of postoperative time for adjuvant radiotherapy in aggressive borderline and malignant phyllodes tumor (PT).

This retrospective study reviewed 13 histopathologically proven borderline and malignant PT, treated with radiation therapy to the dose of 50 Gray by external beam radiotherapy (EBRT) after primary surgical management.

The mean age at presentation was 33 years. Right laterality was more common (60% cases). Although all patients presented with lump, those who had pain as an added symptom turned out to be histopathologically malignant later on. Histopathologically, 66.6% patients were malignant, 20% borderline, and 13.3% benign. High mitotic index and stromal activity were observed in younger patients. Patients who received EBRT within a month of surgery had no local recurrence, whereas those who received EBRT after a month developed local recurrence (P = 0.012).

Adjuvant radiotherapy is appropriate treatment for aggressive borderline and malignant PT. This study revealed that time interval between surgery to initiation of EBRT plays a significant role in the prevention of recurrence.