Malignant phyllodes tumor of the female breast: association of primary therapy with cause-specific survival from the Surveillance, Epidemiology, and End Results (SEER) program.
BACKGROUND
Malignant phyllodes tumor is a rare and potentially aggressive breast neoplasm. Little information is available regarding the optimal management of these lesions and rarer still are data regarding survival. The current study used a large population database to determine prognostic factors that predict cause-specific survival (CSS).


METHODS
Data were obtained from the Surveillance, Epidemiology, and End Results Program (SEER) for the years 1983-2002. Women receiving resection for primary nonmetastatic malignant phyllodes tumor of the breast were included (n = 821). Analyses of patient, pathologic, and treatment characteristics were performed using univariate and multivariate Cox regression analyses for the CSS endpoint.


RESULTS
With a median follow-up of 5.7 years, CSS was 91%, 89%, and 89%, at 5, 10, and 15 years, respectively. Mastectomy was performed in 428 women (52%) and wide excision or lumpectomy in 393 (48%). Women undergoing mastectomy were significantly older (P = .004) and had larger tumors (P = .009). Wide excision was associated with equivalent or improved CSS relative to mastectomy on univariate and multivariate analyses. Older age predicted for cause-specific mortality on multivariate analysis. Adjuvant radiotherapy (RT) predicted for worse CSS when implemented compared with surgery alone.


CONCLUSIONS
Mastectomy was not found to provide a benefit in CSS compared with wide excision in malignant phyllodes tumor of the breast. Women undergoing wide excision had at the minimum similar cancer-specific mortality compared with those who received mastectomy. The role of adjuvant RT is uncertain and requires further investigation.
Macdonald
O Kenneth
OK
Department of Radiation Oncology, Huntsman Cancer Hospital at the University of Utah, Salt Lake City, Utah 84112-5560, USA. kenny.macdonald@hci.utah.edu
Lee
Christopher M
CM
Tward
Jonathan D
JD
Chappel
Craig D
CD
Gaffney
David K
DK
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000401:mortality* / Q000601:surgery / Q000628:therapy*; D002423:Cause of Death; D002648:Child; D015331:Cohort Studies; D003131:Combined Modality Therapy; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008408:Mastectomy; D015412:Mastectomy, Segmental; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000473:pathology*; D003557:Phyllodes Tumor / Q000401:mortality* / Q000601:surgery / Q000628:therapy*; D018714:Radiotherapy, Adjuvant / Q000706:statistics & numerical data; D012307:Risk Factors; D018426:SEER Program / Q000706:statistics & numerical data; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology