Figure 4.

Camera Lucida drawing from a Johannes Erichsen paper of 1861 [58] is the oldest reproduction, in patients with tumors in the lung, of the neoplastic cells occupying the alveolar spaces. No new vessels can be seen while the alveolar septa containing the pre-existing capillaries, produce the “chicken wire” appearance. In the word of the author: “Cross section through a carcinoma nodule of the lungs: the alveoli are shaped by cancerous masses confined between the elastic fibers of the lung tissue”.