It can also be caused by damage to the lymphatic system from infections such as cellulitis.Primary lymphedema may be congenital or arise sporadically. Multiple syndromes are associated with primary lymphedema, including Turner syndrome, Milroys disease, and Klippel-Trenaunay-Weber syndrome. It is generally thought to occur as a result of absent or malformed lymph nodes and/or lymphatic channels. Lymphedema may be present at birth, develop at the onset of puberty (praecox), or not become apparent for many years into adulthood (tarda). In men, lower-limb primary lymphedema is most common, occurring in one or both legs. Some cases of lymphedema may be associated with other vascular abnormalities.Secondary lymphedema affects both men and women. In women, it is most prevalent in the upper limbs after breast cancer surgery, in particular after axillary lymph node dissection, occurring in the arm on the side of the body in which the surgery is performed. Breast and trunk lymphedema can also occur but go unrecognised as there is swelling in the area after surgery, and its symptoms (peau dorange and/or an inverted nipple) can be confused with post surgery fat necrosis. In Western countries, secondary lymphedema is most commonly due to cancer treatment. Between 38 and 89% of breast cancer patients have lymphedema due to axillary lymph node dissection and/or radiation. Unilateral lymphedema occurs in up to 41% of patients after gynecologic cancer.
The tissue now has a spongy consistency and is considered non-pitting: when pressed by the fingertips, the affected area bounces back without indentation. Fibrosis found in Stage 2 lymphedema marks the beginning of the hardening of the limbs and increasing size. Stage 3: Swelling is irreversible and usually the limb(s) or affected area becomes increasingly large. The tissue is hard (fibrotic) and unresponsive; some patients consider undergoing reconstructive surgery, called "debulking". This remains controversial, however, since the risks may outweigh the benefits and the further damage done to the lymphatic system may in fact make the lymphedema worse. Stage 4: The size and circumference of the affected limb(s) become noticeably large. Bumps, lumps, or protrusions (also called knobs) on the skin begin to appear. Stage 5: The affected limb(s) become grossly large; one or more deep skin folds is prevalent among patients in this stage. Stage 6: Knobs of small elongated or small rounded sizes cluster together, giving mossy-like shapes on the limb. Mobility of the patient becomes increasingly difficult. Stage 7: The person becomes "handicapped", and is unable to independently perform daily routine activities such as walking, bathing and cooking. Assistance from the family and health care system is needed. Grades
Lymphedema can also be categorized by its severity (usually referenced to a healthy extremity):
Grade 1 (mild edema): Involves the distal parts such as a forearm and hand or a lower leg and foot. The difference in circumference is less than 4 cm and other tissue changes are not yet present.