Reliable malignant pointers
Radial lines and pseudopods arranged segmentally at the periphery of a pigmented skin lesion are very reliable indicators of malignancy.
With respect to lines radial, the differential diagnosis is limited to melanoma and basal cell carcinoma (BCC).
Pseudopods arranged segmentally occur exclusively in melanomas.
Only two adjacent radial lines or one pseudopod are required.
Radial lines and pseudopods in melanocytic lesions (melanomas and naevi) represent the radial growth of melanoma or naevus cells extending from the tumour body.
They occur either as radial projections from a reticular network or from a tumour mass within, or at the edge of the lesion, and that tumour mass will be at least as dense as the radial structure.
Note that in Figure 2, the radial projections seen in B and D are distributed over the entire periphery of the lesion and are therefore not a clue to