Information is presented on eleven Mayo Clinic patients with postmastectomy lymphangiosarcoma and on two patients with lymphangiosarcoma in lymphedematous extremities in whom malignant disease was unrelated to surgical treatment. One of the latter two tumors occurred in the arm of a patiemit with congenital lymphedema, and the other in the leg of a patient with long-standing idiopathic lymphedema. Also, the clinical and pathological findings in forty-seven previously reported cases of lymphangiosarcoma occurring in postmastectomy lymphedema are summarized. In addition, data on four previously reported examples of lymphangiosarcoma occurring in chronic lymphedema of the leg are given briefly. Finally, reports on seven cases of probable lymphangiosarcoma are reviewed.

The data on the sixty-four accepted examples and on the seven probable examples of this condition are compared. The severe lymphangiomatosis and endothelial hyperplasia of the lymphatic spaces of the subcutaneous tissues would appear to herald the onset and to account for the usual widespread occurrence of the lesions. This latter characteristic, exhibited in the majority of the patients, would appear to explain the poor results of treatment. Despite varying forms and combinations of radical treatment, only twelve of fifty-six patients with postmastectomy lymphedema were alive when last traced. Six of these twelve were known to have had one or more local recurrent or metastatic lesions. Only three of these patients are recorded as surviving after the third year following onset of the disease, one for a period of approximately four years, one for eleven years, and one for twelve years.

Of the forty-four patients known or presumed to be dead (six presumed dead), only six survived for more than three years after onset of the disease. One died forty-two months later of a cerebral vascular accident, and one fifty-two months later by suicide. There was no clinical evidence of lymphangiosarcoma in either patient at the time of death.