Malignant melanoma appearing in a post-mastectomy lymphedematous arm: a novel association of double primary tumors.

The association of a malignant melanoma appearing as an additional primary tumor in the swollen arm adjacent to a mastectomy for breast cancer is reported. A review of the literature revealed only one similar patient previously reported. In both patients, the melanoma and its metastasis were restricted to the lymphedematous arm, appeared 10 years post-mastectomy, and responded to therapy. The similarity to Stewart-Treves syndrome is emphasized. It is suggested that nevi developing in the lymphedematous arm post-mastectomy should be carefully monitored and excised early whenever indicated.