Cutaneous squamous cell carcinoma in situ (SCCis), also known as Bowen disease, is defined histopathologically by malignant keratinocytes that involve the full thickness of the epidermis. This common malignancy is primarily seen in older adults and most frequently occurs on sun-exposed skin. The development of SCCis has also been associated with immunosuppression, chronic lymphocytic leukemia, radiation exposure, arsenic ingestion, and human papillomavirus (HPV). There is no sex predilection. It is frequently seen accompanying other stigmata of chronic sun damage, such as actinic keratoses, solar lentigines, and other keratinocytic carcinomas. If left untreated, SCCis can evolve into invasive SCC.
Erythroplasia of Queyrat refers specifically to SCCis of the glans penis and prepuce, most commonly seen in uncircumcised individuals. It is typically a red, moist, smooth or eroded plaque.
Bowenoid papulosis refers to a high-risk HPV infection (ie, HPV strains 16 and 18) with histologic features of SCCis, usually in the genital or perianal area. Periungual SCCis is also linked to high-risk HPV infection.
Arsenic-induced SCCis can be multifocal and most commonly affects acral surfaces (see arsenical keratosis).
Bowen disease, also known as squamous cell carcinoma in situ (SCC in situ), is a type of cancerous growth that is still trapped in the top layer of the skin. Early cancerous skin changes such as Bowen disease can later spread to deeper layers of the skin and become an invasive cancer. Early detection and treatment of Bowen disease can often prevent the more serious form of skin cancer.
Who’s At Risk
Bowen disease can occur at any age, but is more common in the older population and is slightly more common in women. It is rarely seen in people younger than 30 years of age and is most often seen in people over 60. Bowen disease lesions can be found anywhere on the body, but they are more likely to occur in sun-exposed areas such as the head, neck, and lower legs.
Signs & Symptoms
Bowen disease can first show up as a single pink or scaly spot or multiple spots and usually occurs in sun-exposed areas such as the head, neck, and lower legs. A Bowen disease cancer is usually solid with a well-defined but jagged border that is slightly raised with a pink to red appearance. Bowen disease often has scale or crust on top that may bleed or grow over time. Bowen disease is generally not painful.
Sometimes Bowen disease can also show up as an oozing red raised growth or a flat slightly tan spot. When Bowen disease involves the fingernails, there can be changes in nail color or the appearance of long red bands, separation of the nail from finger, or destruction of the nail.
Bowen disease may also involve the mouth or genital areas. Bowen disease lesions in these areas may also appear as a red spot with irregular borders. However, these spots can also be rough like a wart or appear more like a raised smooth bump.
Self-Care Guidelines
Do regular skin checks to find any new or changing spots or moles by closely inspecting the skin from head to toe and using mirrors to check areas that might be hard to see. If you would like instruction, ask your healthcare provider to show you how.
When to Seek Medical Care
Seek medical help if you have a new or changing spot anywhere on your body that bleeds, oozes, crusts, or does not heal within 1 month. Any growing flat or slightly raised spots that have a flaky, red appearance may be Bowen disease and should be checked by a medical professional.
Treatments
The goal of treatments for Bowen disease is to remove all abnormal cells to prevent the spread and growth of the original spot.
Surgical or destructive therapies:
Surgical excision – Surgical removal of the cancer.
Mohs micrographic surgery – Microscopic surgery used to treat common types of skin cancer where each part of the cancer is removed and checked under the microscope until the whole cancer is gone. This therapy is best for sensitive areas such as the eyes and lips or where other treatment has failed.
Curettage – Scraping or scooping tissue with or without the additional use of cauterizing.
Liquid nitrogen cryosurgery – Freezing the cancer with extreme cold.
Drug therapies:
5-Fluorouracil – A topical cream used to treat many types of skin cancer by damaging the DNA of the cells that cause skin change such as those found in Bowen disease. This therapy is usually only used for small lesions.
Imiquimod – A topical cream used to treat many different skin cancers by stimulating the body's own immune system to attack the abnormal cells such as those found in a Bowen disease cancer.
Other destructive therapies:
Laser ablation – Heating and breaking down the cancer with a laser beam.
Radiotherapy – Heating and breaking down the cancer with radiation.
Photodynamic therapy – Applying a "photosensitizer" drug that only concentrates in the abnormal cells in the cancer and then applying a type of light that activates the drug to destroy the cancer.
There are many ways to treat a Bowen disease cancer, and no one treatment is best for all Bowen disease cancers or different types of patients. Therefore, the size, location, and any previous treatment methods will guide the choice of treatment. It is important to return to your physician after a treatment has been completed so that the area of skin treated can be carefully checked to make sure the cancer does not come back.
References
Duncan KO, Geisse JK, Leffell DJ. Epithelial precancerous lesions. In: Goldsmith LA, Katz SI, Gilchrest BA, Paller AS, Leffell DJ, Dallas NA, eds. Fitzpatrick's Dermatology in General Medicine. 8th ed. New York: McGraw-Hill; 2012:chap 113. http://www.accessmedicine.com/content.aspx?aID=56058492. Accessed March 30, 2013.
Duncan KO, Geisse JK, Leffell DJ. Surgery in Dermatology. In: Goldsmith LA, Katz SI, Gilchrest BA, Paller AS, Leffell DJ, Dallas NA, eds. Fitzpatrick's Dermatology in General Medicine. 8th ed. New York: McGraw-Hill; 2012:section 40. http://www.accessmedicine.com/content.aspx?aID=56058492. Accessed March 30, 2013.