Salivary lymphangioma. Light micrograph of a section through a lymphangioma from a salivary gland. Lymphangiomas are rare usually benign (non-cancerous) tumours of the lymphatic system, consisting of a proliferation of lymph vessels. They resemble blisters that, if damaged, fill with blood giving a red or purple appearance. The growth sometimes disappears on its own, but most cases require surgical removal.