USMLE USMLE Certifications USMLE-STEP-2 Questions & Answers

• Question 151:

  A 35-year-old woman presents to the physician's office for evaluation of a left neck mass discovered 1 month ago on a routine physical examination. On examination, the mass measures 2 cm and is located anterolateral to the larynx and trachea. It is nontender and moves with swallowing. Past history is pertinent for a 15 pack-year smoking history and occasional alcohol intake. For the above patient with a neck mass, select the most likely diagnosis.

  A. thyroid carcinoma

  B. cystic hygroma

  C. acute suppurative lymphadenitis

  D. thyroglossal duct cyst

  E. lipoma

  F. carotid artery aneurysm

  G. mixed parotid tumor (pleomorphic adenoma)

  H. laryngeal carcinoma

  I. parathyroid adenoma

  J. branchial cleft cyst

  K. tuberculosis

  Correct Answer: A

  The location of this neck mass and its movement with swallowing is strongly suggestive of a thyroid mass. The most common type of thyroid cancer is papillary carcinoma, which has an excellent prognosis under the age of 40. Needle biopsy should be performed as a diagnostic test, followed by operation.

• Question 152:

  A 55-year-old man presents to the physician's office with complaints of hoarseness and left neck fullness for the past month. On examination, a firm, movable, left submandibular mass is noted. Past history is pertinent for a 30 packyear smoking history with occasional alcohol intake. For the above patient with a neck mass, select the most likely diagnosis.

  A. thyroid carcinoma

  B. cystic hygroma

  C. acute suppurative lymphadenitis

  D. thyroglossal duct cyst

  E. lipoma

  F. carotid artery aneurysm

  G. mixed parotid tumor (pleomorphic adenoma)

  H. laryngeal carcinoma

  I. parathyroid adenoma

  J. branchial cleft cyst

  K. tuberculosis

  Correct Answer: H

  Laryngeal carcinoma is the most common malignancy of the upper aerodigestive tract in the United States. Presenting symptoms include hoarseness of the voice and, for supraglottic lesions, early metastatic disease to the neck. Risk factors include exposure to tobacco and alcohol.

• Question 153:

  A 50-year-old man presents to the emergency department for increasing abdominal distention and

  jaundice over the last 46 weeks. Examination reveals mild jaundice, spider angiomas, and ascites.

  Enlarged veins are noted around the umbilicus.

  For above patient with jaundice, select the one most likely diagnosis.

  A. hepatitis A

  B. hemolysis

  C. choledocholithiasis

  D. biliary stricture

  E. choledochal cyst

  F. pancreatic carcinoma

  G. liver metastases

  H. cirrhosis

  I. pancreatitis

  Correct Answer: H

  Chronic liver disease, such as cirrhosis, may be a cause of jaundice. Clinical features such as spider angiomas, ascites, and varices suggest cirrhosis.

• Question 154:

  An 18-month-old girl is brought to the physician's office for evaluation of left neck mass. Examination reveals a 2-cm soft, nontender, fluctuant mass in the left lateral neck. This is located at the anterior border of the sternomastoid, midway between the mastoid and clavicle. For the above patient with a neck mass, select the most likely diagnosis.

  A. thyroid carcinoma

  B. cystic hygroma

  C. acute suppurative lymphadenitis

  D. thyroglossal duct cyst

  E. lipoma

  F. carotid artery aneurysm

  G. mixed parotid tumor (pleomorphic adenoma)

  H. laryngeal carcinoma

  I. parathyroid adenoma

  J. branchial cleft cyst

  K. tuberculosis

  Correct Answer: J

  The location of this mass and its cystic nature are typical for a second branchial cleft remnant. Surgical excision is recommended, including the associated tract, which traverses between the carotid bifurcation and ends at the tonsillar fossa.

• Question 155:

  A 50-year-old woman presents to the physician's office for evaluation of a right neck mass. The mass has been present for 3 years and is painless. On examination, a nontender, firm, 2.5-cm mass is noted slightly below and posterior to the angle of the mandible on the right. For the above patient with a neck mass, select the most likely diagnosis.

  A. thyroid carcinoma

  B. cystic hygroma

  C. acute suppurative lymphadenitis

  D. thyroglossal duct cyst

  E. lipoma

  F. carotid artery aneurysm

  G. mixed parotid tumor (pleomorphic adenoma)

  H. laryngeal carcinoma

  I. parathyroid adenoma

  J. branchial cleft cyst

  K. tuberculosis

  Correct Answer: G

  Most tumors of the salivary glands present in the parotid, the most common of which is the pleomorphic adenoma. These occur most frequently in the fifth decade and present as a solitary painless mass in the superficial lobe of the parotid gland. Surgical treatment is complete excision with negative margins.

• Question 156:

  A 6-year-old boy presents to the emergency department with a cough, sore throat, and malaise of 4 days' duration. Examination reveals a temperature of 101.5°F, erythematous pharynx, and a tender right neck mass with overlying erythema. For the above patient with a neck mass, select the most likely diagnosis.

  A. thyroid carcinoma

  B. cystic hygroma

  C. acute suppurative lymphadenitis

  D. thyroglossal duct cyst

  E. lipoma

  F. carotid artery aneurysm

  G. mixed parotid tumor (pleomorphic adenoma)

  H. laryngeal carcinoma

  I. parathyroid adenoma

  J. branchial cleft cyst

  K. tuberculosis

  Correct Answer: C

  Acute suppurative lymphadenitis is related to bacterial pathogens and most often accompanies an infectious illness, such as an upper respiratory tract infection. The nodes enlarge rapidly, are tender, and demonstrate overlying erythema of the skin.

• Question 157:

  A 45-year-old man presents to the physician's office for evaluation of a posterior neck mass. The mass has been present for years, but has slowly enlarged over the last 2 years. Examination reveals a subcutaneous mass that is soft, nontender, and movable. For the above patient with a neck mass, select the most likely diagnosis.

  A. thyroid carcinoma

  B. cystic hygroma

  C. acute suppurative lymphadenitis

  D. thyroglossal duct cyst

  E. lipoma

  F. carotid artery aneurysm

  G. mixed parotid tumor (pleomorphic adenoma)

  H. laryngeal carcinoma

  I. parathyroid adenoma

  J. branchial cleft cyst

  K. tuberculosis

  Correct Answer: E

  Lipomas present as soft, subcutaneous masses that arise in all areas of the body. They are treated by simple excision.

• Question 158:

  A 3-year-old boy presents to the physician's office with an asymptomatic neck mass located in the midline, just below the level of the thyroid cartilage. The mass moves with deglutition and on protrusion of the tongue. For the above patient with a neck mass, select the most likely diagnosis.

  A. thyroid carcinoma

  B. cystic hygroma

  C. acute suppurative lymphadenitis

  D. thyroglossal duct cyst

  E. lipoma

  F. carotid artery aneurysm

  G. mixed parotid tumor (pleomorphic adenoma)

  H. laryngeal carcinoma

  I. parathyroid adenoma

  J. branchial cleft cyst

  K. tuberculosis

  Correct Answer: D

  Athyroglossal duct cyst represents the remnants of the thyroglossal duct tract left over from descent of the thyroid gland from the foramen cecum. It is located in the midline and moves superiorly as the tongue protrudes because the tract communicates with the foramen cecum.

• Question 159:

  A 40-year-old woman presents to the emergency room with a 3-day history of worsening abdominal pain, with nausea and vomiting. Examination reveals a low-grade fever and abdominal tenderness in the right upper quadrant with guarding, especially during inspiration. Laboratory findings include a mild leukocytosis and a slightly elevated bilirubin. For the above patient with abdominal pain, select the most likely diagnosis.

  A. gastroenteritis

  B. regional enteritis

  C. acute appendicitis

  D. perforated peptic ulcer

  E. sigmoid diverticulitis

  F. acute pancreatitis

  G. acute cholecystitis

  H. superior mesenteric artery embolism

  I. ruptured abdominal aortic aneurysm

  J. ruptured ovarian cyst

  K. cecal volvulus

  Correct Answer: G

  Acute appendicitis initially presents with periumbilical pain secondary to obstruction of the appendiceal lumen. This is mediated through visceral pain fibers, and because the appendix is from the embryologic midgut, the pain is referred to the umbilicus. With obstruction of a hollow viscus, there may be associated nausea. As the inflammatory process progresses to involve the visceral and parietal peritoneal surfaces, the pain becomes localized directly over the appendix in the right lower quadrant. Fever and leukocytosis are nonspecific signs of an inflammatory process. Gastroenteritis may be associated with nausea, anorexia, and lowgrade fever. Periumbilical pain is colicky and secondary to increased peristalsis. Localized pain and signs of peritoneal irritation are uncommon. Aruptured right ovarian cyst may mimic appendicitis. Patients may exhibit right lower abdominal peritoneal irritation. However, the onset of pain is usually sudden, and the pain is initially felt in the right lower quadrant.

  These patients do not have anorexia or other gastrointestinal symptoms. The clinical picture of regional enteritis (Crohn's disease) is one of a chronic illness, often associated with weight loss, intermittent cramps, and diarrhea. Fever, tenderness, and a palpable right lower quadrant inflammatory mass may result from complications of ileal involvement. Sigmoid diverticulitis is more common in older patients, often with a prodromal history of irregular bowel habits. There may be left lower quadrant pain and tenderness, with a palpable left-sided inflammatory mass. A cecal volvulus presents with sudden onset of colicky abdominal pain and signs and symptoms of a bowel obstruction, including bilious emesis and abdominal distention. Alcohol-related acute pancreatitis presents with pain referred to the epigastrium, with radiation to the back mediated through the celiac ganglia. The patient may develop abdominal distention secondary to the associated paralytic ileus. Hyperamylasemia and an elevated serum lipase, in this clinical setting, are suggestive of pancreatitis. Perforated peptic ulcer and acute cholecystitis may also present with epigastric pain, and elevations of both serum lipase and amylase. Pain from a perforated ulcer, however, is sudden in onset and may be associated with shoulder-tip pain from diaphragmatic irritation. About 75% of patients with perforated duodenal ulcers have pneumoperitoneum on chest and abdominal radiographs.

  Acute cholecystitis will usually commence after a large meal and initially presents as colicky epigastric pain, progressing to pain localized in the right upper abdomen when transmural inflammation of the gallbladder wall produces peritoneal irritation. Acute mesenteric occlusion presents with sudden onset of severe but poorly localized periumbilical abdominal pain, associated with acidosis. There may be elevation of serum amylase and lipase. A ruptured abdominal aortic aneurysm will present with sudden onset of midabdominal pain, back pain, and hemodynamic instability.

• Question 160:

  A30-year-old man presents with sudden onset of severe epigastric pain 6 hours ago. Examination reveals

  a low-grade fever, tender abdomen throughout, with rigidity of the abdominal usculature.

  Abdominal roentgenograms show pneumoperitoneum.

  For the above patient with abdominal pain, select the most likely diagnosis.

  A. gastroenteritis

  B. regional enteritis

  C. acute appendicitis

  D. perforated peptic ulcer

  E. sigmoid diverticulitis

  F. acute pancreatitis

  G. acute cholecystitis

  H. superior mesenteric artery embolism

  I. ruptured abdominal aortic aneurysm

  J. ruptured ovarian cyst

  K. cecal volvulus

  Correct Answer: D

  Acute appendicitis initially presents with periumbilical pain secondary to obstruction of the appendiceal lumen. This is mediated through visceral pain fibers, and because the appendix is from the embryologic midgut, the pain is referred to the umbilicus. With obstruction of a hollow viscus, there may be associated nausea. As the inflammatory process progresses to involve the visceral and parietal peritoneal surfaces, the pain becomes localized directly over the appendix in the right lower quadrant. Fever and leukocytosis are nonspecific signs of an inflammatory process. Gastroenteritis may be associated with nausea, anorexia, and lowgrade fever. Periumbilical pain is colicky and secondary to increased peristalsis. Localized pain and signs of peritoneal irritation are uncommon. Aruptured right ovarian cyst may mimic appendicitis. Patients may exhibit right lower abdominal peritoneal irritation. However, the onset of pain is usually sudden, and the pain is initially felt in the right lower quadrant.

  These patients do not have anorexia or other gastrointestinal symptoms. The clinical picture of regional enteritis (Crohn's disease) is one of a chronic illness, often associated with weight loss, intermittent cramps, and diarrhea. Fever, tenderness, and a palpable right lower quadrant inflammatory mass may result from complications of ileal involvement. Sigmoid diverticulitis is more common in older patients, often with a prodromal history of irregular bowel habits. There may be left lower quadrant pain and tenderness, with a palpable left-sided inflammatory mass. A cecal volvulus presents with sudden onset of colicky abdominal pain and signs and symptoms of a bowel obstruction, including bilious emesis and abdominal distention. Alcohol-related acute pancreatitis presents with pain referred to the epigastrium, with radiation to the back mediated through the celiac ganglia. The patient may develop abdominal distention secondary to the associated paralytic ileus. Hyperamylasemia and an elevated serum lipase, in this clinical setting, are suggestive of pancreatitis. Perforated peptic ulcer and acute cholecystitis may also present with epigastric pain, and elevations of both serum lipase and amylase. Pain from a perforated ulcer, however, is sudden in onset and may be associated with shoulder-tip pain from diaphragmatic irritation. About 75% of patients with perforated duodenal ulcers have pneumoperitoneum on chest and abdominal radiographs. Acute cholecystitis will usually commence after a large meal and initially presents as colicky epigastric pain, progressing to pain localized in the right upper abdomen when transmural inflammation of the gallbladder wall produces peritoneal irritation. Acute mesenteric occlusion presents with sudden onset of severe but poorly localized periumbilical abdominal pain, associated with acidosis. There may be elevation of serum amylase and lipase. A ruptured abdominal aortic aneurysm will present with sudden onset of midabdominal pain, back pain, and hemodynamic instability.