A 56-year-old woman diagnosed with cancer in her left breast underwent a mastectomy with axillary lymph node dissection. Postoperatively, she develops marked swelling of the left arm that has persisted for 6 months. Now on physical examination, her temperature is 36.9deg C. Her left arm is not tender or erythematous, and it is not painful with movement or to touch, but it is enlarged with a doughy consistency. Which of the following is the most likely mechanism for these findings?