Although the exact cause of vulvar cancer isn't known, certain factors appear to increase your risk of the disease.

- Increasing age

- Exposure to human papillomavirus

- Smoking

- Being infected with the human immunodeficiency virus (HIV)

- Having a history of precancerous conditions of the vulva

- Having a skin condition involving the vulva

Prognosis can range considerably for patients, depending where on the scale they have been staged. Generally speaking, the earlier the cancer is diagnosed, the better the prognosis. The overall 5-year survival rate for all stages of penile cancer is about 50%.

Some conditions such as lichen sclerosus, squamous dysplasia or chronic vulvar itching may precede cancer. In younger women affected with vulvar cancer, risk factors include low socioeconomic status, multiple sexual partners, cigarette use and cervical cancer. Patients that are infected with HIV tend to be more susceptible to vulvar cancer as well. Human papillomavirus (HPV) infection is associated with vulvar cancer.

Penile cancer is a rare cancer in developed nations with annual incidence varying from 0.3 to 1 per 100,000 per year accounting for around 0.4–0.6% of all malignancies. The annual incidence is approximately 1 in 100,000 men in the United States, 1 in 250,000 in Australia, and 0.82 per 100,000 in Denmark. In the United Kingdom, fewer than 500 men are diagnosed with penile cancer every year.

However, in the developing world penile cancer is much more common. For instance, in Paraguay, Uruguay, Uganda and Brazil the incidence is 4.2, 4.4, 2.8 and 1.5–3.7 per 100,000, respectively. In some South American countries, Africa, and Asia, this cancer type constitutes up to 10% of malignant diseases in men.

The lifetime risk has been estimated as 1 in 1,437 in the United States and 1 in 1,694 in Denmark.

Tobacco smoking is associated with an increased risk of ureteral cancer.

A urogenital neoplasm is a tumor of the urogenital system.

Types include:

- Cancer of the breast and female genital organs: (Breast cancer, Vulvar cancer, Vaginal cancer, Cervical cancer, Uterine cancer, Endometrial cancer, Ovarian cancer)

- Cancer of the male genital organs (Carcinoma of the penis, Prostate cancer, Testicular cancer)

- Cancer of the urinary organs (Renal cell carcinoma, Bladder cancer)

Lymphoma is the most common type of blood-related cancer in horses and while it can affect horses of all ages, it typically occurs in horses aged 4–11 years.

When associated with the lung, it is typically a centrally located large cell cancer (non-small cell lung cancer or NSCLC). It often has a paraneoplastic syndrome causing ectopic production of parathyroid hormone-related protein (PTHrP), resulting in hypercalcemia, however paraneoplastic syndrome is more commonly associated with small cell lung cancer.

It is primarily due to smoking.

Human papillomavirus infection (HPV) has been associated with SCC of the oropharynx, lung, fingers and anogenital region.

The main medical risk factors are having bladder cancer or having conditions that cause chronic inflammation in the urethra. People over the age of 60 and white women have the highest risks.

The incidence of squamous cell carcinoma continues to rise around the world. A recent study estimated that there are between 180,000 and 400,000 cases of SCC in the United States in 2013. Risk factors for squamous cell carcinoma varies with age, gender, race, geography, and genetics. The incidence of SCC increases with age and the peak incidence is usually around 60 years old. Males are affected with SCC at a ratio of 2:1 in comparison to females. Caucasians are more likely to be affected, especially those with fair Celtic skin and chronically exposed to UV radiation. Squamous cell carcinoma of the skin is the most common among all sites of the body. Solid organ transplant recipients (heart, lung, liver, pancreas, among others) are also at a heightened risk of developing aggressive, high-risk SCC. There are also a few rare congenital diseases predisposed to cutaneous malignancy. In certain geographic locations, exposure to arsenic in well water or from industrial sources may significantly increase the risk of SCC.

Between 1988 and 2001 in the United States, cancer surveillance reports to SEER included 1,333 cases of ureteral cancer in adults: 808 male and 525 female, 1,158 white and 42 black. Of the total, 1,251 (94%) were transitional cell carcinoma of the papillary type. "Five-year relative survival rates from cancers of the ureter were similar among males vs. females..."

The long-term outcome of squamous cell carcinomas is dependent upon several factors: the sub-type of the carcinoma, available treatments, location(s) and severity, and various patient health-related variables (accompanying diseases, age, etc.). Generally, the long-term outcome is positive, as less than 4% of Squamous cell carcinoma cases are at risk of metastasis. Some particular forms of squamous cell carcinomas have a higher mortality rate. One study found squamous cell carcinoma of the penis had a much greater rate of mortality than some other forms of squamous cell carcinoma, that is, about 23%, although this relatively high mortality rate may be associated with possibly latent diagnosis of the disease due to patients avoiding genital exams until the symptoms are debilitating, or refusal to submit to a possibly scarring operation upon the genitalia. Squamous cell carcinoma occurring in the organ transplant population is also associated with a higher risk of mortality.

Erythroplasia of Queyrat is a squamous-cell carcinoma of the glans penis (head of the penis) or inner prepuce (foreskin) in males, and the vulvae in females. It mainly occurs in uncircumcised males, over the age of 40. Erythroplasia of Queyrat may also occur on the anal mucosa or the oral mucosa.

Some sources state that this condition is synonymous with Bowen's disease, however generally speaking Bowen's disease refers to carcinoma in situ of any location on the skin such as the lower leg. Like Bowen's disease, erythroplasia of Queyrat is associated with human papillomavirus 16 and is a precursor for invasive squamous-cell carcinoma.

It is named for French dermatologist Louis Queyrat (1856-1933), who was head of the dermatology service of l'Hôpital Ricord, a venereal hospital in Paris, now Hôpital Cochin.

Erythroplakia has an unknown cause but researchers presume it to be similar to the causes of squamous cell carcinoma. Carcinoma is found in almost 40% of erythroplakia. It is mostly found in elderly men around the ages of 65 - 74. It is commonly associated with smoking.

Alcohol and tobacco use have been described as risk factors.

Urethral cancer is cancer originating from the urethra. Cancer in this location is rare, and the most common type is papillary transitional cell carcinoma. The most common site of urethral cancer is the bulbomembranous urethra.

Tumors related to squamous-cell carcinoma (SCC) can appear anywhere on the body, but they are most often located in non-pigmented skin near mucocutaneous junctions (where skin meets mucous membranes) such as on the eyelids, around the nostrils, lips, vulva, prepuce, penis or anus. The tumors are raised, fleshy, often ulcerated or infected and may have an irregular surface. Rarely, primary SCC develops in the esophagus, stomach (non-glandular portion), nasal passages and sinuses, the hard palate, gums, guttural pouches and lung. The eyelid is the most common site, accounting for 40-50% of cases, followed by male (25-10% of cases) and female (10% of cases) genitalia. Horses with lightly pigmented skin, such as those with a gray hair coat or white faces, are especially prone to developing SCC, and some breeds, such as Clydesdales, may have a genetic predisposition. Exposure of light-colored skin to UV light has often been cited as a predisposing factor, but lesions can occur in dark skin and in areas that are not usually exposed to sunlight, such as around the anus. Buildup of smegma ("the bean" in horseman's terms) on the penis is also linked to SCC and is thought to be a carcinogen through penile irritation. Pony geldings and work horses are more prone to developing SCC on the penis, due to less frequent penile washing when compared to stallions. Equine papillomavirus-2 has also been found within penile SCCs, but has not been determined to cause SCC.

It is also known that disruption of the endocrine system by certain chemicals adversely affects the development of the reproductive system and can cause vaginal cancer. Many other reproductive diseases have also been link to exposure to synthetic and environmental chemicals. Common chemicals with known links to reproductive disorders include: lead, dioxins and dioxin-like compounds, styrene, toluene, BPA (Bisphenol A) and pesticides.

Studies show a link between HPV infection and penile and anal cancers. Sexually transmitted HPVs are found in a large percentage of anal cancers. Moreover, the risk for anal cancer is 17 to 31 times higher among gay and bisexual men than among heterosexual men

- though one survey did not find a difference between the HPV infection rate of men who had sex with men versus those who had sex only with women.

Anal Pap smear screening for anal cancer might benefit some subpopulations of men or women engaging in anal sex. No consensus exists, though, that such screening is beneficial, or who should get an anal Pap smear.

Verruciform xanthoma is uncommon, with a female:male ratio of 1:1.1

High-risk carcinogenic HPV types (including HPV 16 and HPV 18) are associated with an increasing number of head and neck cancers.

Sexually transmitted forms of HPV account for about 25% of cancers of the mouth and upper throat (the oropharynx). The latter commonly present in the tonsil area, and HPV is linked to the increase in oral cancers in nonsmokers. Engaging in anal or oral sex with an HPV-infected partner may increase the risk of developing these types of cancers. Oral infection with several types of HPV, in particular type 16, have been found to be associated with HPV-positive oropharyngeal cancer, a form of head and neck cancer. This association is independent of tobacco and alcohol use. In the United States, HPV is expected to replace tobacco as the main causal agent for oral cancer, and the number of newly diagnosed, HPV-associated head and neck cancers is expected to surpass that of cervical cancer cases by 2020.

In recent years, the United States has experienced an increase in the number of cases of throat cancer caused by HPV type 16. Throat cancers associated with HPV have been estimated to have increased from 0.8 cases per 100,000 people in 1988 to 2.6 per 100,000 in 2004. Researchers explain these recent data by an increase in oral sex. Moreover, findings indicate this type of cancer is much more prevalent in men than in women, something that needs to be further explored. Currently, two immunizations, Gardasil and Cervarix, are recommended to girls to prevent HPV-related cervical cancer, but not as a precaution against HPV-related throat cancer.

The mutational profile of HPV-positive and HPV-negative head and neck cancer has been reported, further demonstrating that they are fundamentally distinct diseases.

Examples of congenital abnormalities of the reproductive system include:

- Kallmann syndrome - Genetic disorder causing decreased functioning of the sex hormone-producing glands caused by a deficiency or both testes from the scrotum.

- Androgen insensitivity syndrome - A genetic disorder causing people who are genetically male (i.e. XY chromosome pair) to develop sexually as a female due to an inability to utilize androgen.

- Intersexuality - A person who has genitalia and/or other sexual traits which are not clearly male or female.

In male dogs, the tumor affects the penis and foreskin. In female dogs, it affects the vulva. Rarely, the mouth or nose are affected. The tumor often has a cauliflower-like appearance. Signs of genital TVT include a discharge from the prepuce and in some cases urinary retention, from blockage of the urethra. Signs of a nasal TVT include nasal fistulae, nosebleeds and other nasal discharge, facial swelling, and enlargement of the submandibular lymph nodes.

Surgery may be difficult due to the location of these tumors. Surgery alone often leads to recurrence. Chemotherapy is very effective for TVTs. The prognosis for complete remission with chemotherapy is excellent. The most common chemotherapy agents used are vincristine, vinblastine, and doxorubicin. Radiotherapy may be required if chemotherapy does not work.

Treatment involves biopsy of the lesion to identify extent of dysplasia. Complete excision of the lesion is sometimes advised depending on the histopathology found in the biopsy. Even in these cases, recurrence of the erythroplakia is common and, thus, long-term monitoring is needed.