Koh VCY, et al. - This study entailed the correlation of the clinicopathological parameters to survival outcomes in patients diagnosed with malignant Phyllodes tumours (PTs) of the breast. The findings revealed that tumour size and the presence of malignant heterologous elements speculated the metastasis in malignant PTs. In order to ascertain if protein biomarkers and genomic aberrations refined the metastatic risk and defined therapeutic targets, additional exploration was necessitated.

Methods

• Herein, 83 cases of malignant PTs were scrutinized.
• These cases were diagnosed at the Department of Anatomical Pathology, Singapore General Hospital from 1994 to 2015.
• Clinicopathological features and follow-up were yielded from hospital records.
• Researchers computed the metastasis-free survival (MFS) and overall survival (OS) via the Kaplan-Meier method and compared between groups using the log-rank test.
• Cox regression assisted in determining the factors predictive for metastasis.

Results

• It was noted that the mean and median age of patients was 48 years (range 21-71 years).
• Tumour size measured from 30 to 220 mm (mean 90 mm, median 77 mm). Follow-up data was available for 68 patients.
• Mean and median follow-up was 90 and 57 months, respectively, with a maximum of 291 months.
• The occurrence of distant metastasis was noted in 16 out of 68 patients (23.5%).
• Lung was discovered to be the most common site of metastasis.
• Malignant heterologous elements were reported in 16 (19.3%) cases.
• Individual clinicopathological parameters did not exert an influence on the outcome.
• The Kaplan-Meier analysis unveiled that women with large tumours and presence of malignant heterologous elements presented with trends for poorer MFS (p=0.217 and p=0.566, respectively).
• The combination of large tumours (≥ 90 mm) containing malignant heterologous elements, however, revealed considerably worse MFS (p=0.043) and a trend for poorer OS (p=0.238).
• Large tumours harbouring malignant heterologous elements independently speculated the metastasis (95% CI 1.041-12.517, HR 2.434, p=0.049), as disclosed by the multivariate analysis.