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Benign tumors
Published in Rashmi Sarkar, Anupam Das, Sumit Sethi, Concise Dermatology, 2021
This is an uncommon benign tumor of smooth muscle that arises either from arrector pili muscle of hair follicles or from the smooth muscle of blood vessel walls. It can be confused histologically because of its spindle-shaped and strap-shaped plain muscle cells, which may look like fibrous or neural tissue. They are classified into piloleiomyomas, genital leiomyomas, and angioleiomyomas. Eruptive leiomyomas are reported in patients with haematological malignancies, especially chronic lymphocytic leukaemia.
Hereditary Leiomyomatosis and Renal Cell Cancer
Published in Dongyou Liu, Handbook of Tumor Syndromes, 2020
Leiomyoma (synonym: leiomyomata) is a benign neoplasm that evolves from the erector pili muscle of the pilosebaceous unit (cutaneous leiomyoma/piloleiomyoma), the cutaneous vascular smooth muscle fibers (angioleiomyoma), or the dartos muscle (genital leiomyoma/uterine leiomyoma). Histologically, leiomyoma displays whorled (fascicular) pattern of smooth muscle bundles separated by well vascularized connective tissue, elongated smooth muscle cells with eosinophilic or occasional fibrillar cytoplasm and distinct cell membranes, low (<5) mitotic figures per 10 high power, absence of significant atypia, and lack of hemorrhage and necrosis (Figures 31.1b and 31.2b). However, leiomyoma has the potential to undergo malignant transformation and turn into leiomyosarcoma, which demonstrates obvious nuclear atypia, high mitotic activity, large size, frequent hemorrhage, and necrosis [7].
The locomotor system
Published in C. Simon Herrington, Muir's Textbook of Pathology, 2020
There are three main types of benign smooth muscle tumours in soft tissue. Cutaneous leiomyomas arise from erector pili muscles and are usually multiple and painful. Genital leiomyomas, e.g. those arising from the dartos muscle in the scrotum, are usually solitary and painless, whereas vascular leiomyomas originate from abnormal thick-walled veins and typically form painful lumps in the legs of middle-aged patients, particularly females. Leiomyomas consist of spindle-shaped cells that closely resemble normal smooth muscle cells.
A rare case of congenital piloleiomyoma of the eyelid
Published in Orbit, 2021
Shahid Alam, Prabrisha Banerjee, Subramanian Krishnakumar
Cutaneous leiomyomas (CLs) are rare benign smooth muscle neoplasm of the skin. Rudolf Virchow first identified this entity in 1854 and he termed it as “tuberculum dolorosum”.1 Based on the site of origin, CL is classified as a) piloleiomyoma which is the tumor of the arrector pili muscle of the hair follicles, b) angioleiomyoma originating from the tunica media of the small to medium-sized vessels and c) dartoic or genital leiomyoma arising from the smooth muscle of genital skin.1,2 Piloleiomyoma is the most common variant of cutaneous leiomyoma.3 It usually affects the adult population. Extensor surface of limbs and trunk are the sites involved more commonly.1 Head and neck is an extremely rare site for piloleiomyoma.4 While acquired piloleiomyomas are the most common variant of leiomyomas; their congenital variant is extremely rare.5 Congenital piloleiomyoma arising from the eyelid has never been reported in the literature and we for the first time are reporting a congenital piloleiomyoma of the eyelid. The child’s parents gave informed consent for the publication of the photograph for research purpose and the case report adhered to the tenets of Declaration of Helsinki.