Differential Diagnosis for the Lesion Lateral to the Eye

• Single Most Likely Diagnosis
  • BCC (Basal Cell Carcinoma): This is the most common type of skin cancer and frequently occurs on the face, including areas around the eyes. It can present with pigmentation and ulceration, especially if it becomes advanced.
• Other Likely Diagnoses
  • SCC (Squamous Cell Carcinoma): Another common skin cancer that can occur in sun-exposed areas, including the face. It may show pigmentation changes and can ulcerate, especially in older adults.
  • Melanoma: Although less common than BCC or SCC, melanoma is a significant concern due to its potential for metastasis. It can present as a pigmented lesion and may ulcerate, but it's less likely to be the first consideration without other specific signs like the ABCDE criteria (Asymmetry, Border, Color, Diameter, Evolving).
• Do Not Miss Diagnoses
  • Melanoma: Despite being listed under other likely diagnoses, melanoma is a "do not miss" diagnosis due to its high potential for malignancy and the need for early intervention. Missing a melanoma could be deadly.
  • Marjolin’s Ulcer: This is a rare but aggressive type of squamous cell carcinoma that arises in chronic wounds or scars. Although less likely, it's crucial not to miss this diagnosis due to its poor prognosis if left untreated.
• Rare Diagnoses
  • Marjolin’s Ulcer: While mentioned under "do not miss," it's also rare. The context of the question (lateral to the eye, pigmentation, and ulceration) makes other diagnoses more likely, but Marjolin’s Ulcer remains a consideration in the differential due to its potential severity.
  • Other rare skin cancers or conditions: Such as Merkel cell carcinoma, sebaceous gland carcinoma, or adnexal tumors, which can present with similar symptoms but are less common.