Precancerous lesion in the context of Carcinoma in situ

⭐ Core Definition: Precancerous lesion

A precancerous condition is a condition, tumor or lesion involving abnormal cells which are associated with an increased risk of developing into cancer. Clinically, precancerous conditions encompass a variety of abnormal tissues with an increased risk of developing into cancer. Some of the most common precancerous conditions include certain colon polyps, which can progress into colon cancer, monoclonal gammopathy of undetermined significance, which can progress into multiple myeloma or myelodysplastic syndrome, and cervical dysplasia, which can progress into cervical cancer. Bronchial premalignant lesions can progress to squamous cell carcinoma of the lung.

Pathologically, precancerous tissue can range from benign neoplasias, which are tumors which don't invade neighboring normal tissues or spread to distant organs, to dysplasia, a collection of highly abnormal cells which, in some cases, has an increased risk of progressing to anaplasia and invasive cancer which is life-threatening. Sometimes, the term "precancer" is also used for carcinoma in situ, which is a noninvasive cancer that has not grown and spread to nearby tissue, unlike the invasive stage. As with other precancerous conditions, not all carcinoma in situ will become an invasive disease but is at risk of doing so.

↓ Menu

Precancerous lesion in the context of Human papillomavirus infection

Human papillomavirus infection (HPV infection) is an infection caused by a DNA virus from the Papillomaviridae family. Many HPV infections cause no symptoms and 90% resolve spontaneously within two years. Sometimes an HPV infection persists and results in warts or precancerous lesions. Many warts are caused by HPV. These lesions, depending on the site affected, increase the risk of cancer of the cervix, vulva, vagina, penis, anus, mouth, tonsils, or throat. Nearly all cervical cancer is due to HPV and two strains, HPV16 and HPV18, account for 70% of all cases. HPV16 is responsible for almost 90% of HPV-related cancers of the mouth, throat, or tonsils. Between 60% and 90% of the other cancers listed above are also linked to HPV. HPV6 and HPV11 are common causes of genital warts and laryngeal papillomatosis.

Over 200 types of HPV have been described. An individual can become infected with more than one type of HPV and the disease is only known to affect humans. More than 40 types may be spread through sexual contact and infect the anus and genitals. Risk factors for persistent infection by sexually transmitted types include early age of first sexual intercourse, multiple sexual partners, smoking and poor immune function. These types are typically spread by direct skin-to-skin contact, with vaginal and anal sex being the most common methods. HPV infection can spread from a mother to baby during pregnancy. There is limited evidence that HPV can spread indirectly, but some studies suggest it is theoretically possible to spread via contact with contaminated surfaces. HPV is not killed by common hand sanitizers or disinfectants, increasing the possibility of the virus being transferred via non-living infectious agents called fomites.

View the full Wikipedia page for Human papillomavirus infection

↑ Return to Menu