A 48-year-old woman has developed persistent swelling and puffiness in the left arm after a mastectomy with axillary node dissection for breast cancer 1 year ago. She developed cellulitis in the left arm 3 months ago. Physical examination shows firm skin over the left arm and “doughy” underlying soft tissue. The arm is not painful or discolored. Which of the following terms best describes these findings?

**Core Concept**
Lymphedema is a chronic condition characterized by the abnormal accumulation of protein-rich fluid in the interstitial tissue, leading to swelling and fibrosis of the affected limb. It often occurs as a complication of lymph node dissection or radiation therapy.

**Why the Correct Answer is Right**
The patient's history of mastectomy with axillary node dissection and subsequent development of cellulitis increases her risk of lymphedema. The firm skin and "doughy" underlying soft tissue are consistent with fibrosis and lymphatic obstruction. The absence of pain or discoloration suggests a chronic process rather than an acute infection. The accumulation of protein-rich fluid in the interstitial tissue leads to swelling and fibrosis, which is a hallmark of lymphedema.

**Why Each Wrong Option is Incorrect**
**Option A:**
This term refers to a condition characterized by the accumulation of fluid in the peritoneal cavity, often due to a blockage of lymphatic or venous drainage. It does not describe the patient's condition, which involves the accumulation of fluid in the interstitial tissue of the arm.

**Option B:**
This term refers to a condition characterized by the abnormal accumulation of fluid in the pleural space, often due to a blockage of lymphatic or venous drainage. It does not describe the patient's condition, which involves the accumulation of fluid in the interstitial tissue of the arm.

**Option C:**
This term is not a recognized medical condition. It is a distractor and does not accurately describe the patient's symptoms.

**Clinical Pearl / High-Yield Fact**
Lymphedema is a chronic condition that can be prevented or managed with early intervention, including the use of compression garments and pneumatic compression devices. Regular self-care and skin care are also essential in preventing skin breakdown and infection.

**Correct Answer:** C. Lymphedema.

✓ Correct Answer: A. Lymphedema