WBR0802
| Author | [[PageAuthor::Gonzalo A. Romero, M.D. [1]]] |
|---|---|
| Exam Type | ExamType::USMLE Step 2 CK |
| Main Category | |
| Sub Category | SubCategory::Dermatology |
| Prompt | [[Prompt::A 42-year-old blond man originally from Portland at age 17 and has been working as a fisherman in the Caribbean. He comes to the clinic complaining of multiple nevi. He recently noticed that one of them has changed in appearance and is enlarging. The nevus has multiple colors within the lesion, irregular borders and measures 1.9 cm. A picture of the lesion is shown below. Which of the following is the most important prognostic predictor?
 |
| Answer A | AnswerA::Diameter |
| Answer A Explanation | [[AnswerAExp::Incorrect.]] |
| Answer B | AnswerB::Color |
| Answer B Explanation | [[AnswerBExp::Incorrect.]] |
| Answer C | AnswerC::Depth of invasion |
| Answer C Explanation | [[AnswerCExp::Correct.]] |
| Answer D | AnswerD::Multiple nevi |
| Answer D Explanation | [[AnswerDExp::Incorrect.]] |
| Answer E | AnswerE::Location |
| Answer E Explanation | [[AnswerEExp::Incorrect.]] |
| Right Answer | RightAnswer::C |
| Explanation | [[Explanation::Features that affect prognosis are tumor thickness in millimeters (Breslow's depth), depth related to skin structures (Clark level), type of melanoma, presence of ulceration, presence of lymphatic/perineural invasion, presence of tumor infiltrating lymphocytes (if present, prognosis is better), location of lesion, presence of satellite lesions, and presence of regional or distant metastasis.
Certain types of melanoma have worse prognoses but this is explained by their thickness. Interestingly, less invasive melanomas even with lymph node metastases carry a better prognosis than deep melanomas without regional metastasis at time of staging. Local recurrences tend to behave similarly to a primary unless they are at the site of a wide local excision (as opposed to a staged excision or punch/shave excision) since these recurrences tend to indicate lymphatic invasion. Educational Objective:
 Educational Objective: |
| Approved | Approved::No |
| Keyword | WBRKeyword::melanoma, WBRKeyword::skin cancer |
| Linked Question | Linked:: |
| Order in Linked Questions | LinkedOrder:: |