A 78-year-old woman comes to the office with a scab in her left ear that she first felt 2 weeks ago. The lesion is slightly painful. There have been no changes in hearing or recent trauma to the ear. The patient lives alone and cannot see the lesion. Medical history includes essential hypertension. Ear examination is shown in the exhibit. The external auditory meatus and tympanic membrane are normal. There is no lymphadenopathy in the head or neck. Biopsy shows invasive squamous cell carcinoma. Which of the following is the most appropriate treatment for this patient's condition?
Squamous cell carcinoma of skin | ||
Risk factors |
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Clinical features |
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Diagnosis |
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Treatment | Invasive SCC
| SCC in situ
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5-FU = 5-fluorouracil; C&E = curettage & electrodesiccation; SCC = squamous cell carcinoma. | ||
This patient has squamous cell carcinoma (SCC) in the concha of the ear, a cosmetically and functionally sensitive area that carries a high risk for recurrence and distant metastasis. The management of SCC is determined largely by the risks for recurrence and metastasis, which are based primarily on the location, size, and histologic characteristics of the cancer:
Low-risk SCC includes most lesions <2 cm on the trunk or extremities, excluding the hands and feet.
High-risk SCC includes lesions on the face, ears, neck, hands, feet, or genitalia, especially those ≥1 cm; lesions ≥2 cm in any location; and lesions with an aggressive histology and invasion of nearby structures (eg, nerves, vessels, lymphatics).
Mohs micrographic surgery is generally the first-line treatment for high-risk SCC. This technique sequentially removes thin skin layers with intraoperative microscopic margin inspection to ensure complete removal of the cancer, resulting in a higher cure rate than standard excision. In addition, sequential tissue removal allows for maximal preservation of normal tissue, making it ideal for SCC located in cosmetically and functionally sensitive areas, or in anatomic locations where standard excision with margins is unfeasible (eg, the ear).
(Choice A) Curettage and electrodesiccation destroys the cancer mechanically and electrically but does not allow for histologic margin evaluation and is associated with inferior cosmetic outcomes. This treatment is generally reserved for low-risk tumors in cosmetically nonsensitive areas (eg, trunk, extremities).
(Choice B) Localized radiation therapy may be considered if surgical options are contraindicated or not preferred, but it is not well studied and has significant adverse effects (eg, acute radiation skin toxicity, injury to underlying structures, secondary malignancy).
(Choices D and E) Topical 5-fluorouracil and cryotherapy with topical liquid nitrogen are commonly used for actinic keratosis, a common premalignant condition that may give rise to SCC. Topical 5-fluorouracil can also be used to treat SCC in situ (eg, Bowen disease), in which the malignancy is limited to the epidermis, but neither treatment is recommended for invasive SCC.
Educational objective:
High-risk squamous cell carcinoma (eg, on the face or ears) is generally best managed with Mohs micrographic surgery. This technique has a higher cure rate compared to standard excision, and its ability to maximally preserve normal tissue also makes it the preferred method for removing tumors in cosmetically and functionally sensitive areas.