Answer:
The incidence of arm lymphedema varies greatly in the literature. In
the more recent studies the range is between 6% and 30%. The studies with
the lowest incidence had the shorter follow-up time 12 months. The other
source of variation in incidence is the definition of lymphedema with some
studies using circumference difference between arms (usually > 2cm) and
other studies using volumetric difference usually >200 ml. The natural
history of post-mastectomy lymphedema is variable. Arm edema may develop
immediately and either settles or persists. Alternatively, swelling may
develop months or years after the original uneventful surgery. The treatment
of lymphedema is difficult and multidisciplinary in nature. The therapies
can be divided into three general categories: rehabilitative, pharmacologic,
and surgery. Elevation is among the first intervention recommended to reduce
the hydrostatic pressure thereby decreasing production of lymph. Manual
lymphatic drainage is used alone or incorporated with skin care, bandaging,
and exercise in a comprehensive approach called complex decongestive therapy.
Compression garments and pneumatic compression devices are widely used
. Pharmacotherapy with coumarin, a benzopyrone which stimulates proteolysis
by macrophages, had mixed results with a recent New England Journal article
study showing no effect. Surgical therapy may involve debulking in the
excess tissue and fluid is removed. The other strategy is to enhance lymphatic
function. A variety of flaps including omental and myocutaneous flaps have
been devised. Microlymphatic-venous anastomosis allow removal of lymph
through the proximal venous system.