Tumors that originate from the arrectores
pilorum muscles are called pilar LMA and usually occur in the skin, whereas those that derive from the muscular coats of blood vessels are called ALMAs and usually occur in smooth muscles of the lower extremities .
Vimentin-immunoreactivity was very dense in the smooth muscle cells of blood vessels, it was positively stained in the arrectores
pilorum muscles (Fig.
Madam, Piloleiomyomas are benign smooth muscle tumours arising from the arrectores
pilorum muscles in the skin, and they are rare dermal tumours.1 They usually present as small, reddish-brown or skin-coloured, firm, often painful papules or as nodules on the trunk and the extremities.
Smooth muscle of skin area is present only in the walls of blood vessels, along hair follicles (arrectores
pilorium), and the dartos muscle in the scrotum (1,3,6).
Structure and evolutionary implications of the musculi arrectores
pilorum in Chiroptera.
Arrectores pilorum muscle (Figure 5 & 6) was prominent.
1) Multiple piloleiomyomas-both arising from arrectores pilorum muscle