title: Predicting clinical behaviour of breast phyllodes tumours: a nomogram based on histological criteria and surgical margins.
abstract: OBJECTIVE
  To define a predictive model for clinical behaviour of breast phyllodes tumours (PT) using histological parameters and surgical margin status.
  
  
  METHODS
  Cases of breast PT diagnosed in the Department of Pathology Singapore General Hospital between January 1992 and December 2010 were stratified into benign, borderline and malignant grades based on a combination of histological parameters (stromal atypia, hypercellularity, mitoses, overgrowth and nature of tumour borders). Surgical margin status was assessed. Clinical follow-up and biostatistical modelling were accomplished.
  
  
  RESULTS
  Of 605 PT, 440 (72.7%) were benign, 111 (18.4%) borderline and 54 (8.9%) malignant. Recurrences, which were predominantly local, were documented in 80 (13.2%) women. Deaths from PT occurred in 12 (2%) women. Multivariate analysis revealed stromal atypia, overgrowth and surgical margins to be independently predictive of clinical behaviour, with mitoses achieving near significance. Stromal hypercellularity and tumour borders were not independently useful. A nomogram developed based on atypia, mitoses, overgrowth and surgical margins (AMOS criteria) could predict recurrence-free survival at 1, 3, 5 and 10 years. This nomogram was superior to a total histological score derived from adding values assigned to each of five histological parameters.
  
  
  CONCLUSIONS
  A predictive nomogram based on three histological criteria and surgical margin status can be used to calculate recurrence-free survival of an individual woman diagnosed with PT. This can be applied for patient counselling and clinical management.
authors: Department of Pathology, Singapore General Hospital, Singapore. tan.puay.hoon@sgh.com.sg
authors: Puay Hoon
authors: PH
authors: Tan
authors: Aye Aye
authors: AA
authors: Thike
authors: Wai Jin
authors: WJ
authors: Tan
authors: Minn Minn Myint
authors: MM
authors: Thu
authors: Inny
authors: I
authors: Busmanis
authors: Huihua
authors: H
authors: Li
authors: Wen Yee
authors: WY
authors: Chay
authors: Min-Han
authors: MH
authors: Tan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001706:Biopsy; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000401:mortality / Q000473:pathology / Q000601:surgery; D049109:Cell Proliferation; D016009:Chi-Square Distribution; D018572:Disease-Free Survival; D005260:Female; D006769:Hospitals, General; D006801:Humans; D053208:Kaplan-Meier Estimate; D016013:Likelihood Functions; D008408:Mastectomy / Q000706:statistics & numerical data; D008875:Middle Aged; D008940:Mitotic Index; D008954:Models, Biological; D060787:Neoplasm Grading; D009364:Neoplasm Recurrence, Local; D049451:Nomograms; D003557:Phyllodes Tumor / Q000175:diagnosis* / Q000401:mortality / Q000556:secondary / Q000601:surgery; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D018570:Risk Assessment; D012307:Risk Factors; D012846:Singapore; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult