Chlamydia is not only the most frequently transmissible sexually active infection; for women who have contracted it the risk of developing ovarian cancer is double. A survey conducted by the American Association for Cancer Research identified the danger and the link between sexual infection and cancer in terms of the relationship between cause and effect. If it is true that ovarian cancer is relatively rare (there are about 5,200 cases recorded in Italy in 2017) the prognosis is serious, with only 38% of patients surviving five years after diagnosis. There are several reasons for this: the aggressive nature of the cancer, the lack of obvious symptoms at the onset and its discovery at an advanced stage. Hence the importance of identifying the causes and understanding if there are other ones, in addition to those of a genetic nature. We talked about it with Dr. Isabella Garassino, oncologist at Humanitas.

Cancer and Chlamydia

Chlamydia is an infection with very mild symptoms but serious consequences for the reproductive system. It affects sexually active women, especially adolescents and young people. This is the infection to which the US study has associated a twice higher risk of ovarian cancer. Chlamydia is transmitted through sexual intercourse and any clinical manifestations that occur after one to three weeks of infection. It is diagnosed by a laboratory test that aims to identify the bacterium on infected tissues, in biological fluids (urine, sperm, secretions) or in the blood. In women it is typically manifested by pelvic inflammation: the involvement of tubes, ovaries, uterus and surrounding tissues can result in permanent damage. Permanent damage that in men seems less likely, although some studies indicate a possible correlation between infection and infertility. For preventive purposes, sexually active women under 25 years of age are recommended to have an annual screening. Because of its bacterial nature, chlamydia can be treated with antibiotics. Partners should also be treated.

Papilloma Virus, AIDS and venereal diseases

Among other sexually transmitted viruses, Papilloma Virus (HPV) is known to be the main cause of cervical cancer and other cancers affecting the vulva, vagina, anus, penis and oropharynx/mouth. In Italy, it is estimated that each year Papilloma Virus is responsible for about 6,500 new cases of cancer in both sexes, about 12 thousand anogenital lesions of high grade in women and at least 80 thousand cases of genital condylomas (or warts), diseases that could disappear or become very rare thanks to vaccination. As for AIDS, it is known that HIV-positive people are more at risk than certain forms of cancer, such as Kaposi’s sarcoma and some forms of Hodgkin and non-Hodgkin’s lymphomas, agenital, liver and mouth neoplasms. HIV-AIDS attacks against and weakens the immune system, which plays an important role in cancer surveillance. HIV has also been linked to the risk of other forms of cancer, including nonmelanoma skin, eye and lung cancers. The relationship between so-called venereal diseases (gonorrhoea and syphilis) and tumors appears to be milder, partly because of the sharp reduction in the number of cases observed. It should be noted that a 2014 study pointed out that gonorrhea infection in humans increased the risk of prostate cancer and that, historically, in syphilis patients there was an increase in the generic risk of cancer (especially oropharynx cancer and Kaposi’s sarcoma).