USMLE-STEP-2 Exam Questions & Answers

Correct Answer: D

This ECG reveals ST-segment elevation in II, III, and AVF, indicating acute injury of the inferior wall of the myocardium. Inferior wall ischemia can be perceived as pain in the epigastric area. Anterolateral myocardial infarction would show loss of R-wave progression in V4 through V6. Pericarditis would show diffuse ST segment elevation in limb and precordial leads. Although his symptoms could suggest gastroesophageal reflux, this ECG shows this a cardiac event. Costochondritis is not present by examination. When ST segment elevation is present, a patient should be considered a candidate for reperfusion therapy or primary percutaneous intervention (PCI) such as angioplasty and stenting. If no contraindications are present and PCI is unavaliable, thrombolytic therapy should ideally be initiated within 30 minutes, right in the emergency department. The goal of both thrombolysis and PCI is prompt restoration of coronary arterial patency. Thrombolytic therapy can reduce the risk of in- hospital death by up to 50% when administered within the first hour of symptoms, so time is of the essence. Arranging for a bed may waste time for limiting infarct size. The ECG would obviously preclude the other two options: immediate trial of antacid or reassurance and arranging outpatient follow-up.

Correct Answer: D

After two normal Pap smears, women with normal risk can be screened every 3 years. The USPSTF has found no evidence that annual screening provides better outcomes than screening every 3 years. The majority of cervical cancers in the United States occur in women who have never been screened, those who did not receive appropriate follow-up after an abnormal Pap smear, or those who have not been screened within the past 5 years.

Correct Answer: D

Prospective randomized trials have addressed the issue of locoregional control of breast cancer. Conservative management consisting of lumpectomy (with negative margins), irradiation, and axillary node dissection is equally effective as modified radical mastectomy in patients with clinical stage I or II breast carcinoma. Although radical mastectomy yields equivalent survival to modified radical mastectomy, it is disfiguring and disabling and is rarely employed for treatment of primary operable breast cancer. Lumpectomy without irradiation leads to unacceptably high local recurrence rates. Irradiation without surgery is not as effective as surgery in the presence of gross disease. Quadrantectomy removes excessive tissue and leads to an inferior cosmetic result as compared to lumpectomy. If quadrantectomy is thought to be required to gain negative margins, mastectomy with reconstruction should be entertained. The use of SLN biopsy to stage the axilla in breast cancer is gaining wider acceptance as experience with the procedure grows. Trials are ongoing that will answer numerous questions regarding the accuracy and efficacy of SLN biopsy for breast cancer. There are contraindications to SLN biopsy that include palpable adenopathy that is suspicious for metastatic disease, locally advanced disease or tumor size >5 cm, multicentric disease, pregnant or lactating patient, and use of preoperative chemotherapy. Therefore, in this patient with palpable suspicious adenopathy, SLN biopsy would be contraindicated. Although age may influence success of SLN biopsy, increasing age does not preclude the procedure.