This week’s USMLE Step 1 question looks at a patient who is referred to an oncologist. See if you can answer the question and then watch the video to learn the correct answer as well as the rationales for all of the options. The video comes from a recent edition of the Rx Question Lab, so if you like it, we encourage you to register and tune in every Tuesday.
A 24-year-old man comes to the physician for a routine physical examination before beginning a new job. The physician notes a small, firm nodule on the patient’s left testicle, and he is subsequently diagnosed with a testicular seminoma and referred to an oncologist. Soon after beginning high-dose chemotherapy, the patient returns to his primary care physician because of a 1-week history of dry cough and shortness of breath. His temperature is 98.7°F (37°C), and his pulse is 82/min. His respiratory rate is 17/min. A cardiac examination discloses no murmurs or gallops, and both lungs are clear to auscultation without wheezes; there is no dullness to percussion. Imaging results are shown.
Which of the following is the major mechanism of the chemotherapeutic agent that was most likely used to treat this patient’s seminoma?
A. Alkylation of DNA
B. Formation of superoxide or hydroxide radicals
C. Inhibition of microtubule polymerization
D. Inhibition of topoisomerase II
E. Stabilization of microtubules against depolymerization
We invite you to leave a comment with your answer as well as your rationale. When you’re ready to check your work, watch the video.
Are you getting serious about the USMLE Step 1? Or prepping for NBMEs? Fall is here and temperatures are falling, which means more opportunities to study! But if you don’t have the right study tools, that time may wind up being misspent.
We invite you to spend 5 days with USMLE-Rx, free of charge. We’ll show you why more med students are opting for Rx to help them succeed on their board exams. What’s more, even after your trial expires, you’ll still be able to access over 150 of our revolutionary Rx Bricks.
Hear what some students are saying about how USMLE-Rx has helped them with med school, board prep, and getting ready for the USMLE Step 1:
- “The question bank is a great way to prepare for our NBME exams and offers challenging problems that actually test knowledge.” J.S., Nova
- “Easy to use platform, wide variety of questions with similar difficulty to nbme.” E.C., Vanderbilt
- “Helps me score really well in NBMEs and my school blocks. My scores went up by 20% just by using Rx.”
- “I think USMLE-Rx is a great way to prepare for step/NBME exam, providing high yield and challenging questions. As well as videos and resources to aid in the learning process.” B.V., Eastern Virginia Medical School
- “USMLE Rx helped me greatly in studying for the Comprehensive Basic Science Exam. My NBME scores went up over 15 points (on the USMLE predicted score) from going through the USMLE-Rx question bank and videos. I am so thankful.” K.S.
- “These questions have helped to prepare me for my med school NBMEs as well as with Step 1 preparation.” A.P., Indiana University
- “Because of USMLE-Rx I was able to pass my basic science nbme comprehensive exam. It has provided me with the ways to understand everything conceptually.” J.S.
- “The question bank is difficult but highly correlated to material seen on NBME examinations.” K. B., Ross University
- “Very helpful for exams, especially since our school uses NBME exams throughout the first two years. Also beneficial for step 1 prep and review and helps me utilize First Aid effectively.” J.B.
- “I already recommend Rx and the physical FA textbook to all of my classmates and the people in the year below me. The QMax tests represent NBME exams in my courses really well and I feel prepared for my exams after doing these as practice exams.” J.A., Florida International
- “Excellent resource—practice questions are great, study materials and videos are good. Integration of first aid and flash facts and questions based on video sections watched is incredible. Extremely helpful for NBME exams and prep.” R.H.
- “When I was using this, it was teaching me some concepts that I never understood before. I also liked the cumulative/nbme type of test attached to Rx.” A.A.
- “Using this resource was essential in facilitating and solidifying my understanding prior to NBME exams during my didactic curriculum, as well as in preparation for Step 1….These videos and the question banks comprised over 95% of my studying during the didactics phase of my curriculum.” J.N., Oregon Health and Science University
- “The practice questions are phenomenal and are very representative of the nbme questions.” M.T., University of Texas, Galveston
- “Because Rx has helped me improve dramatically with my NBME exams. It’s bedrock for me with proven results!” Y.S.
Start your free trial today and see how USMLE-Rx can help you get on track!