WBR0804
| Author | [[PageAuthor::Gonzalo A. Romero, M.D. [1]]] |
|---|---|
| Exam Type | ExamType::USMLE Step 1 |
| Main Category | MainCategory::Pathology |
| Sub Category | SubCategory::Dermatology |
| Prompt | [[Prompt::A 68-year-old man comes to the clinic complaining of an ulcer on his face. He has been a sailor for his entire life. It is indolent in nature. The patient states that it has been growing slowly over the past 9 months. On physical exam it is clean looking, has 2 cm in diameter and is located on the lower lip. There are no lymphadenopathies in the head or neck. A surgeon performs an excision with clear margins. The pathologist finds epithelized cells in concentric fashion with a focus of central keratinization on the microscope. Which of the following risk factors and types of cancer has similar findings on the microscope?]] |
| Answer A | AnswerA::Smoking - squamous cell carcinoma of the esophagus |
| Answer A Explanation | [[AnswerAExp::Correct. See overall explanation]] |
| Answer B | AnswerB::Alcohol - adenocarcinoma of the esophagus |
| Answer B Explanation | [[AnswerBExp::Incorrect. Alcohol consumption and smoking are associated with squamous cell carcinoma of the esophagus. Adenocarcinomas are often associated with a history of gastroesophageal reflux disease and Barrett's esophagus.]] |
| Answer C | AnswerC::Cocaine - septal nasal perforation |
| Answer C Explanation | [[AnswerCExp::Incorrect. This association is correct, but does not cause the the changes found on light microscopy. Cocaine causes vasoconstriction which limits the blood flow causing ischemic necrosis and nasal septum perforation.]] |
| Answer D | AnswerD::Low fiber diet - adenocarcinoma of the colon |
| Answer D Explanation | [[AnswerDExp::Incorrect. High fiber diet, particularly cereal and whole grains, can absorb carcinogens from the diet decreasing colorectal cancer risk.]] |
| Answer E | AnswerE::Smoking - bronchogenic adenocarcinoma |
| Answer E Explanation | [[AnswerEExp::Incorrect. Smoking is associate with higher risk of developing bronchogenic adenocarcinoma. Its histologic findings correspond to malignant mucin producing cells (glands).]] |
| Right Answer | RightAnswer::A |
| Explanation | [[Explanation::Esophageal cancer (or oesophageal cancer) is malignancy of the esophagus. There are various subtypes, primarily squamous cell cancer (approx 90–95% of all esophageal cancer worldwide) and adenocarcinoma (approx. 50–80% of all esophageal cancer in the United States). Squamous cell cancer arises from the cells that line the upper part of the esophagus. Adenocarcinoma arises from glandular cells that are present at the junction of the esophagus and stomach. The stem describes the histologic findings of squamous cell carcinoma due to the presence of keratin pearls (epithelized cells in concentric fashion with a focus of central keratinization).
Educational Objective:
Educational Objective: |
| Approved | Approved::No |
| Keyword | WBRKeyword::skin cancer, WBRKeyword::Squamous cell carcinoma, WBRKeyword::keratin pearls |
| Linked Question | Linked:: |
| Order in Linked Questions | LinkedOrder:: |