From the Guidelines
The treatment of this condition will most likely prevent squamous cell carcinoma (F). The patient presents with multiple dry, scaly, hyperkeratotic lesions on sun-exposed areas (hands, arms, and ears) that have been persistent and increasing in size over years. These findings are consistent with actinic keratoses, which are premalignant lesions caused by chronic UV radiation exposure. The patient's history as a farmer and skier indicates significant sun exposure, which is the primary risk factor. Actinic keratoses are considered precursors to squamous cell carcinoma, with approximately 5-10% of untreated lesions progressing to invasive squamous cell carcinoma over time 1. Treatment options include cryotherapy, topical 5-fluorouracil, imiquimod, photodynamic therapy, or curettage for isolated lesions. Additionally, the patient should be counseled on sun protection measures including sunscreen use, protective clothing, and avoiding peak sun hours to prevent development of new lesions and further skin damage. Some key recommendations for the management of actinic keratosis include the use of UV protection, field treatment with 5-fluorouracil or imiquimod, and cryosurgery 1. The benefits of 5-FU treatment for AK were assessed as moderate or large, based on studies assessed field treatment with 5-FU 1. It is also important to note that sunscreen use has been associated with a small decrease in the incidence of SCCs and AKs over a short follow-up period 1. Overall, the treatment of actinic keratosis is crucial in preventing the progression to squamous cell carcinoma. Key points to consider in the treatment of this condition include:
- The use of UV protection to prevent further skin damage
- Field treatment with 5-fluorouracil or imiquimod to reduce the rate of onset of new AKs
- Cryosurgery as a treatment option for isolated lesions
- Sun protection measures, including sunscreen use, protective clothing, and avoiding peak sun hours.
From the FDA Drug Label
Fluorouracil Cream USP is recommended for the topical treatment of multiple actinic or solar keratoses. In the 5% strength, it is also useful in the treatment of superficial basal cell carcinomas when conventional methods are impractical, such as with multiple lesions or difficult treatment sites. The success rate with Fluorouracil Cream USP is approximately 93%, based on 113 lesions in 54 patients. Eighty-eight lesions treated with the cream produced 7 failures.
The treatment of actinic keratosis will most likely prevent squamous cell carcinoma and possibly basal cell carcinoma.
- The correct answer is:
- A. basal cell carcinoma
- F. squamous cell carcinoma However, based on the information provided in the question and the drug labels, the best answer is F. squamous cell carcinoma 2.
From the Research
Treatment of Actinic Keratosis
The patient's symptoms are consistent with actinic keratosis (AK), a premalignant lesion that can progress to squamous cell carcinoma (SCC) 3, 4, 5, 6, 7. Treatment of AK is essential to prevent the development of SCC.
Prevention of Malignant Transformation
Treatment of AK can prevent the malignant transformation of the lesion into SCC 4, 5, 6, 7. The goal of treatment is to eliminate the abnormal cells and prevent further progression.
Options for Prevention
The options for prevention of malignant transformation are:
- Prevention of basal cell carcinoma: not directly related to AK treatment 3
- Prevention of bullous impetigo: not directly related to AK treatment 3
- Prevention of bullous pemphigoid: not directly related to AK treatment 3
- Prevention of melanocytic Spitz nevus: not directly related to AK treatment 3
- Prevention of melanoma: not directly related to AK treatment 3
- Prevention of squamous cell carcinoma: directly related to AK treatment 3, 4, 5, 6, 7
Most Likely Prevention
Treatment of AK will most likely prevent the development of:
Key points to consider: