Erythroplasia of Queyrat may also occur on the anal mucosa or the oral mucosa. Some sources state that this condition is synonymous with Bowens disease, however generally speaking Bowens disease refers to carcinoma in situ of any location on the skin such as the lower leg. Genetically, SCC tumors harbor high frequencies of NOTCH and p53 mutations as well as less frequent alterations in histone acetyltransferase EP300, subunit of the SWI/SNF chromatin remodeling complex PBRM1, DNA-repair deubiquitinase USP28, and NF-κB signaling regulator CHUK. Immunosuppression
People who have received solid organ transplants are at a significantly increased risk of developing squamous cell carcinoma due to the use of chronic immunosuppressive medication. While the risk of developing all skin cancers increases with these medications, this effect is particularly severe for SCC, with hazard ratios as high as 250 being reported, versus 40 for basal cell carcinoma. The incidence of SCC development increases with time posttransplant. Heart and lung transplant recipients are at the highest risk of developing SCC due to more intensive immunosuppressive medications used.Squamous cell cancers of the skin in individuals on immunotherapy or who have lymphoproliferative disorders (e.g. leukemia) tend to be much more aggressive, regardless of their location. The risk of SCC, and non-melanoma skin cancers generally, varies with the immunosuppressive drug regimen chosen. The risk is greatest with calcineurin inhibitors like cyclosporine and tacrolimus, and least with mTOR inhibitors, such as sirolimus and everolimus. The antimetabolites azathioprine and mycophenolic acid have an intermediate risk profile.
Elephantiasis is the enlargement and hardening of limbs or body parts due to tissue swelling. It is characterised by edema, hypertrophy, and fibrosis of skin and subcutaneous tissues, due to obstruction of lymphatic vessels. It may affect the genitalia. The term elephantiasis is often used in reference to (symptoms caused by) parasitic worm infections, but may refer to a variety of diseases where parts of a persons body swell to massive proportions. Cause
Some conditions that present with elephantiasis include:

Elephantiasis nostras, due to longstanding chronic lymphangitis
Elephantiasis tropica (known as lymphatic filariasis), caused by a number of parasitic worms, particularly Wuchereria bancrofti. More than 120 million people, mostly in Africa and Southeast Asia, are affected. Nonfilarial elephantiasis (or podoconiosis), an immune disease affecting the lymph vessels
Leishmaniasis
Elephantiasis, Grade 3 lymphedema which may occur in people with breast cancer
Genital elephantiasis, result of lymphogranuloma venereum
Proteus syndrome, a genetic disorder best known as the condition possibly experienced by Joseph Merrick, the so-called "Elephant Man. "Other causes may include:

Repeated streptococcal infection
Lymphadenectomy
Hereditary birth defects
Pretibial myxedema

References
External links

"Lymphatic filariasis". World Health Organization. Retrieved 1 June 2018.