Background information:
(1) About a quarter of all phyllodes tumors will recur due to an inadequate initial excision, especially if the surgeon enucleated ("shelled out") the lesion.
(2) The tumor may contain peripheral projections that can only be removed by excising a rim of normal tissue all around the tumor.
(3) A margin >= 1 cm around the tumor usually is sufficient to prevent recurrence in low grade and borderline tumors.
(4) For a large tumor the quality of cosmetic restoration becomes important.
(5) Patient preference
Indications for mastectomy:
(1) large, overtly malignant tumor (cystosarcoma)
(2) very large tumor relative to breast size
(3) no other way to achieve adequate negative margins based on tumor location
(4) would make cosmetic reconstruction simpler
Usually a simple mastectomy is performed, but axillary node sampling may be performed if the tumor is overtly malignant or if palpable lymphadenopathy is present.
