WBR0250
| Author | [[PageAuthor::Rim Halaby, M.D. [1]]] |
|---|---|
| Exam Type | ExamType::USMLE Step 1 |
| Main Category | MainCategory::Genetics, MainCategory::Pathology |
| Sub Category | SubCategory::Dermatology, SubCategory::Oncology |
| Prompt | [[Prompt::A 42 year old previously healthy male patient presented to the dermatology clinics for rapidly increasing nevus on the left side of his face. The patient reports that the lesion has been increasing in size and getting progressively darker since a few months. Evaluation of the lesion reveals a 2.5cm x 1.5cm nevus with irregular border and heterogeneous dark color. Biopsy was taken and it reveals extensive proliferation of melanocytes. Loss of function of which of the following tumor suppressor genes is associated with this condition?]] |
| Answer A | AnswerA::APC |
| Answer A Explanation | [[AnswerAExp::Loss of function of the gene APC is associated with colorectal cancer, mainly familial adenomatous polyposis.]] |
| Answer B | AnswerB::WT1 |
| Answer B Explanation | [[AnswerBExp::Loss of function of the gene WT1 is associated with Wilm's tumor.]] |
| Answer C | AnswerC::DPC |
| Answer C Explanation | AnswerCExp::Loss of function of the gene DPC is associated with pancreatic cancer. |
| Answer D | AnswerD::p16 |
| Answer D Explanation | AnswerDExp::Loss of function of the gene p16 is associated with melanoma. |
| Answer E | AnswerE::Rb |
| Answer E Explanation | [[AnswerEExp::Loss of function of the gene Rb is associated with retinoblastoma and osteosarcoma.]] |
| Right Answer | RightAnswer::D |
| Explanation | [[Explanation::The patient presents with a nevus characterized by irregular borders, increasing darkening and heterogeneous discoloration. The characteristics of this nevus suggest the presence of melanoma which had to be confirmed by a biopsy. Loss of function of the tumor suppressor gene p16 , expressed on gene 9q, is associated with the development of melanoma.
Educational objective: Loss of function of the tumor suppressor gene p16 , expressed on gene 9q, is associated with the development of melanoma. |
| Approved | Approved::No |
| Keyword | |
| Linked Question | Linked:: |
| Order in Linked Questions | LinkedOrder:: |