title: Malignant Phyllodes Tumor Presenting in Bone, Brain, Lungs, and Lymph Nodes.
abstract: BACKGROUND
  Phyllodes tumors (PTs) are rare fibroepithelial tumors of the breast which are classified as benign, borderline, or malignant. Malignant PTs account for <1% of malignant breast tumors, and borderline tumors have potential to progress to malignant tumors. Metastatic recurrences are most commonly documented in bone and lungs. We report an extremely rare presentation of recurrent malignant PTs involving the brain, lung, lymph nodes, and bone.
  
  
  METHODS
  A 66-year-old female presented with a large breast mass. Biopsy identified malignant PT, treated by mastectomy. One year later she presented with acute back pain; imaging showed pathological L4 spinal compression fracture. Core biopsy confirmed PT. Staging identified additional metastases in the lymph nodes, brain, and lung.
  
  
  CONCLUSIONS
  PTs are rare and fast-growing tumors that originate from periductal stromal tissues and are composed of both epithelial and stromal components. Histologically, they are classified as benign, borderline, or malignant. The prognosis of the malignant type is poorly defined, with local recurrence occurring in 10-40% and metastases in 10%. Chemotherapy and radiotherapy are generally ineffective in this tumor type. The most common metastatic sites for malignant cases are the lung and bones, but in rare instances, PTs may metastasize elsewhere.
  
  
  CONCLUSIONS
  We report a rare presentation of recurrent malignant PT presenting as pathological fracture of the lumbar spine with impingement on the spinal column, along with cerebellar, nodal, and pulmonary metastases. Only 1 similar case has been previously reported.
authors.affiliation: Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City, UT, USA.
authors.forename: Eric D
authors.initials: ED
authors.lastname: Johnson
authors.affiliation: Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT, USA.
authors.forename: Evin
authors.initials: E
authors.lastname: Gulbahce
authors.affiliation: Department of Radiology, University of Utah School of Medicine, Salt Lake City, UT, USA.
authors.forename: Joseph
authors.initials: J
authors.lastname: McNally
authors.affiliation: Huntsman Cancer Institute at the University of Utah School of Medicine, Salt Lake City, UT, USA.
authors.forename: Saundra S
authors.initials: SS
authors.lastname: Buys
keywords: Breast cancer; Metastasis; Phyllodes sarcoma; Phyllodes tumor; Recurrence