Familial cylindomatosis is an autosomally inherited genetic condition, characterized by numerous benign tumors of skin adnexa, principally on the head and neck. The tumors arise from the hair follicles, sweat glands, and sebaceous glands, and exist as circumscribed, non-encapsulated, dermal forms without any attachment to the epidermis. In addition, the tumors are made up of numerous oval and angulated subunits, arranged in an interlocking pattern. In fact, these angulated subunits are what differentiate the tumor from spiradenomas. Other neoplasms that share clinical findings with cylindromatosis include Brooke-Speigler Syndrome, and Multiple Familial Trichoepithelioma. The subunits are surrounded by PAS positive, glassy, basement membrane.
Cylindromatosis usually affects individuals in their second or third decade of life, and shows a female preponderance. Malignant transformation is very rare. Treatment involves surgical removal and skin grafting.
The gene responsible for familial cylindromatosis is the CLYD gene on chromosome 16q12-q13. The normal function of the CLYD gene is complex and diverse. CLYD has been shown to interact with various members of the pro-apoptotic NF-Kappa B signaling pathway, including TRAF-2 (TNF receptor Associated factor 2), TRIP (TRAF Interacting Protein), and IKK gamma/Nemo (I Kappa B Kinase, Gamma), and thereby, negatively regulating NF-Kappa B activation. Thus, loss of action of CLYD leads to a loss of apoptotis control, ensuing in cell proliferation. Recently, aspirin has been shown to counteract the negative effects of CLYD inactivation and induce apoptosis, and a treatment with aspirin is being considered for cylindromatosis.