A 50-year-old female patient presented with swelling of the left upper limb with some characteristic skin lesions. Patient gave history of undergoing MRM followed by chemotherapy and radiotherapy 7 years ago. A skin biopsy was taken. Which of the following markers would be most likely be positive in the above patient: -

This is a case of Stewa-Treves syndrome. Develops in patients many years after mastectomy, more commonly 5-15 years after surgery. Severe chronic edema of an upper extremity The edematous area gradually extends from arm to forearm and dorsal aspect of the hand and fingers. The lesions of Stewa-Treves syndrome typically appear as multiple reddish blue macules or nodules that may become polypoid. Around these nodules, small satellite areas can develop and become confluent, forming an enlarging lesion. HPE image shows the classical picture of a lymphangiosarcoma (spindle shaped neoplastic cells along with RBCs at low power). Positive staining for laminin, CD31, collagen IV, and vimentin can aid in diagnosing the tumors as angiosarcomas.