title: Phyllodes tumour with heterologous sarcomatous differentiation: Case series with literature review.
abstract: BACKGROUND
  Phyllodes tumours are rare fibroepithelial malignancies of the breast, accounting for less than 1% of malignant breast tumours. Further malignant differentiation of phyllodes tumours can occur, resulting in cases of extremely rare heterologous sarcomatous differentiation.
  
  
  METHODS
  Two females in their fifties were diagnosed with malignant phyllodes tumour associated with heterologous sarcomatous differentiation. The first patient, aged 50 had phyllodes tumour with chondrosarcoma, osteosarcoma and ductal carcinoma-in-situ. The second patient, aged 53 had phyllodes tumour with osteosarcoma and liposarcoma.
  
  
  CONCLUSIONS
  The association of phyllodes tumour and heterologous sarcomatous differentiation is rare, with only 4 previously reported cases in English literature. The paucity of evidence presents challenges in its management with uncertain prognosis and monitoring requirements for two aforementioned patients.
  
  
  CONCLUSIONS
  Further case series and long-term follow up is required for accurate characterisation of phyllodes tumours with heterologous sarcomatous differentiation.
authors.affiliation: Department of Breast Surgery, Royal Prince Alfred Hospital, Camperdown, NSW, Australia; Department of Surgery, Prince of Wales Hospital, Randwick, NSW, Australia; Faculty of Medicine, University of Sydney, Australia; RPA Institute of Academic Surgery, Sydney Local Health District, Australia. Electronic address: rsanjaywarrier@hotmail.com.
authors.forename: Sanjay
authors.initials: S
authors.lastname: Warrier
authors.affiliation: Department of Surgery, Prince of Wales Hospital, Randwick, NSW, Australia; Prince of Wales Hospital Clinical School, University of New South Wales, Australia.
authors.forename: Sang Y
authors.initials: SY
authors.lastname: Hwang
authors.affiliation: Department of Breast Surgery, Royal Prince Alfred Hospital, Camperdown, NSW, Australia.
authors.forename: Keagan
authors.initials: K
authors.lastname: Gibbings
authors.affiliation: Department of Breast Surgery, Royal Prince Alfred Hospital, Camperdown, NSW, Australia; Faculty of Medicine, University of Sydney, Australia.
authors.forename: Hugh
authors.initials: H
authors.lastname: Carmalt
authors.affiliation: Faculty of Medicine, University of Sydney, Australia; RPA Institute of Academic Surgery, Sydney Local Health District, Australia.
authors.forename: Sandra
authors.initials: S
authors.lastname: O'Toole
keywords: Breast; Phyllodes tumour; Sarcoma; Surgery