NBME PATHOLOGY EXAM – COMPLETE STUDY GUIDE &
PATHOPHYSIOLOGY REVIEW (2026 EDITION)
General Pathology
1. A 72-year-old man with severe atherosclerosis experiences a sudden drop in blood pressure
following a myocardial infarction. At autopsy, a section of his small intestine shows areas of
hemorrhagic infarction. What is the most likely underlying mechanism for this bowel
damage?
A. Coagulative necrosis due to protease activation
B. Liquefactive necrosis due to bacterial infiltration
C. Ischemic coagulative necrosis from arterial occlusion
D. Hemorrhagic necrosis from reperfusion injury
E. Fat necrosis from release of pancreatic enzymes
Answer: D. Hemorrhagic necrosis from reperfusion injury. ✓
Explanation: The scenario describes a transient period of ischemia (from hypotension) followed
by reperfusion (when blood pressure is restored). Reperfusion injury leads to damage of the
capillary endothelium, causing bleeding into the necrotic tissue, resulting in a hemorrhagic
appearance. Pure arterial occlusion (C) typically causes pale infarction.
2. A 25-year-old woman presents with acute onset of right lower quadrant pain. Histological
examination of the resected appendix reveals numerous neutrophils infiltrating the
muscularis propria. This cellular response is primarily mediated by the release of which of the
following?
A. IL-1 and TNF-alpha
B. IL-4 and IL-13
C. IL-5 and eosinophil chemotactic factor
D. TGF-beta and platelet-derived growth factor (PDGF)
E. Histamine and bradykinin
Answer: A. IL-1 and TNF-alpha. ✓
*Explanation: IL-1 and TNF-alpha are key pro-inflammatory cytokines released by macrophages
and other cells in response to tissue damage or infection. They upregulate endothelial adhesion
molecules (e.g., E-selectin) and promote the chemotaxis and emigration of neutrophils from the
vasculature into the tissue.*
3. A 60-year-old man with a long history of alcohol abuse is found to have micronodular
cirrhosis. A liver biopsy reveals Mallory-Denk hyaline within hepatocytes. This finding is best
,described as an accumulation of which of the following?
A. Glycogen
B. Intermediate filaments
C. Cholesterol
D. Phospholipids
E. Triglycerides
Answer: B. Intermediate filaments. ✓
*Explanation: Mallory-Denk hyaline (or Mallory bodies) are cytoplasmic inclusions composed of
tangled intermediate filaments (primarily cytokeratins 8 and 18). They are a characteristic,
though not specific, feature of alcoholic liver disease.*
4. A 45-year-old woman has a breast biopsy that shows ductal carcinoma in situ (DCIS). She is
concerned about the potential for invasion. Which of the following is the most critical genetic
alteration associated with the progression of DCIS to invasive ductal carcinoma?
A. Inactivation of the NF1 tumor suppressor gene
B. Activation of the *HER2/neu* oncogene
C. Inactivation of the BRCA1 tumor suppressor gene
D. Degradation of the basement membrane and stromal invasion
E. Activation of the RAS oncogene
Answer: D. Degradation of the basement membrane and stromal invasion. ✓
Explanation: The defining feature separating in situ from invasive carcinoma is the breaching of
the basement membrane. This process involves the production of proteases (like matrix
metalloproteinases) by tumor cells, allowing them to invade the surrounding stroma. While the
other options are involved in carcinogenesis, the loss of basement membrane integrity is the key
step in progression to invasion.
5. A 70-year-old man with chronic hypertension suffers a cerebrovascular accident. A non-
contrast CT scan shows a hyperdense area in the left basal ganglia. This finding is most
consistent with which type of cellular injury?
A. Coagulative Necrosis
B. Liquefactive Necrosis
C. Caseous Necrosis
D. Fibrinoid Necrosis
E. Fat Necrosis
Answer: B. Liquefactive Necrosis. ✓
Explanation: In the central nervous system, ischemic injury typically results in liquefactive
necrosis. This is characterized by the dissolution of tissue by potent lysosomal enzymes released
,from microglia and neutrophils, forming a liquid viscous mass. The hyperdense area on CT in this
clinical context is an acute hemorrhage, but the underlying necrotic process will be liquefactive.
Cardiovascular Pathology
6. A 55-year-old man presents with severe, crushing substernal chest pain radiating to his left
arm. ECG shows ST-segment elevations in the anterior leads. Serum troponin I is elevated. The
myocardial damage in this patient is best characterized by which of the following?
A. Apoptosis
B. Coagulative necrosis
C. Liquefactive necrosis
D. Caseous necrosis
E. Fibrinoid necrosis
Answer: B. Coagulative necrosis. ✓
Explanation: Myocardial infarction (MI) results in coagulative necrosis, the typical pattern of
ischemic cell death in solid organs (except the brain). It is characterized by preservation of the
basic tissue architecture for several days despite the death of the cells.
7. The gross appearance of the left ventricle in the patient from the previous question,
examined 3-4 days post-infarction, would most likely show which of the following?
A. No gross changes
B. A pale, firm, wedge-shaped area
C. A yellow, soft area with central liquefaction
D. A hyperemic border with a central yellow-tan softening
E. A white, scarred, fibrotic area
Answer: D. A hyperemic border with a central yellow-tan softening. ✓
*Explanation: At 3-4 days, the infarction is in the stage of necrosis and softening. The center
becomes yellow-tan and soft due to neutrophilic infiltration and enzymatic digestion, while the
surrounding area has a hyperemic border of inflammation.*
8. A 40-year-old woman presents with a butterfly rash on her face, arthralgias, and pleuritic
chest pain. Serologic testing is positive for anti-dsDNA antibodies. Which of the following
vascular lesions is most characteristic of this disease?
A. Atherosclerosis
B. Medial calcific sclerosis
C. Libman-Sacks endocarditis
D. Granulomatous vasculitis
E. Hyperplastic arteriolosclerosis
, Answer: C. Libman-Sacks endocarditis. ✓
Explanation: The patient has systemic lupus erythematosus (SLE). Libman-Sacks endocarditis is a
classic finding, characterized by non-bacterial verrucous endocarditis on the valve surfaces.
9. A 5-year-old boy presents with fever, conjunctival injection, a strawberry tongue, and a
desquamating rash on his palms and soles. An echocardiogram reveals aneurysms of the
coronary arteries. This condition is associated with pathology in which of the following blood
vessels?
A. Aorta
B. Large muscular arteries
C. Small arteries
D. Arterioles
E. Capillaries
Answer: B. Large muscular arteries. ✓
Explanation: This describes Kawasaki disease, which is an acute febrile illness of childhood
characterized by a systemic vasculitis that has a predilection for the coronary arteries, which are
large muscular arteries.
10. A 65-year-old man with a history of poorly controlled hypertension presents with a
sudden, severe "tearing" pain in his chest and back. His blood pressure is 180/110 mmHg in
the right arm and 150/90 mmHg in the left arm. The most likely diagnosis is a dissection
originating in the:
A. Ascending aorta (Type A)
B. Descending aorta (Type B)
C. Abdominal aorta
D. Aortic arch
E. Thoracic aorta distal to the left subclavian artery
Answer: A. Ascending aorta (Type A). ✓
Explanation: The classic presentation of an aortic dissection includes severe tearing pain and
blood pressure discrepancies between arms. A Type A dissection (involving the ascending aorta)
is a surgical emergency and can compromise the coronary arteries, aortic valve, and great
vessels, leading to the described blood pressure difference.
Pulmonary Pathology
11. A 60-year-old man with a 100-pack-year smoking history presents with a 2-cm solitary
pulmonary nodule in the periphery of the right upper lobe. A biopsy shows malignant cells
forming glands. This tumor is most likely:
A. Small cell carcinoma
PATHOPHYSIOLOGY REVIEW (2026 EDITION)
General Pathology
1. A 72-year-old man with severe atherosclerosis experiences a sudden drop in blood pressure
following a myocardial infarction. At autopsy, a section of his small intestine shows areas of
hemorrhagic infarction. What is the most likely underlying mechanism for this bowel
damage?
A. Coagulative necrosis due to protease activation
B. Liquefactive necrosis due to bacterial infiltration
C. Ischemic coagulative necrosis from arterial occlusion
D. Hemorrhagic necrosis from reperfusion injury
E. Fat necrosis from release of pancreatic enzymes
Answer: D. Hemorrhagic necrosis from reperfusion injury. ✓
Explanation: The scenario describes a transient period of ischemia (from hypotension) followed
by reperfusion (when blood pressure is restored). Reperfusion injury leads to damage of the
capillary endothelium, causing bleeding into the necrotic tissue, resulting in a hemorrhagic
appearance. Pure arterial occlusion (C) typically causes pale infarction.
2. A 25-year-old woman presents with acute onset of right lower quadrant pain. Histological
examination of the resected appendix reveals numerous neutrophils infiltrating the
muscularis propria. This cellular response is primarily mediated by the release of which of the
following?
A. IL-1 and TNF-alpha
B. IL-4 and IL-13
C. IL-5 and eosinophil chemotactic factor
D. TGF-beta and platelet-derived growth factor (PDGF)
E. Histamine and bradykinin
Answer: A. IL-1 and TNF-alpha. ✓
*Explanation: IL-1 and TNF-alpha are key pro-inflammatory cytokines released by macrophages
and other cells in response to tissue damage or infection. They upregulate endothelial adhesion
molecules (e.g., E-selectin) and promote the chemotaxis and emigration of neutrophils from the
vasculature into the tissue.*
3. A 60-year-old man with a long history of alcohol abuse is found to have micronodular
cirrhosis. A liver biopsy reveals Mallory-Denk hyaline within hepatocytes. This finding is best
,described as an accumulation of which of the following?
A. Glycogen
B. Intermediate filaments
C. Cholesterol
D. Phospholipids
E. Triglycerides
Answer: B. Intermediate filaments. ✓
*Explanation: Mallory-Denk hyaline (or Mallory bodies) are cytoplasmic inclusions composed of
tangled intermediate filaments (primarily cytokeratins 8 and 18). They are a characteristic,
though not specific, feature of alcoholic liver disease.*
4. A 45-year-old woman has a breast biopsy that shows ductal carcinoma in situ (DCIS). She is
concerned about the potential for invasion. Which of the following is the most critical genetic
alteration associated with the progression of DCIS to invasive ductal carcinoma?
A. Inactivation of the NF1 tumor suppressor gene
B. Activation of the *HER2/neu* oncogene
C. Inactivation of the BRCA1 tumor suppressor gene
D. Degradation of the basement membrane and stromal invasion
E. Activation of the RAS oncogene
Answer: D. Degradation of the basement membrane and stromal invasion. ✓
Explanation: The defining feature separating in situ from invasive carcinoma is the breaching of
the basement membrane. This process involves the production of proteases (like matrix
metalloproteinases) by tumor cells, allowing them to invade the surrounding stroma. While the
other options are involved in carcinogenesis, the loss of basement membrane integrity is the key
step in progression to invasion.
5. A 70-year-old man with chronic hypertension suffers a cerebrovascular accident. A non-
contrast CT scan shows a hyperdense area in the left basal ganglia. This finding is most
consistent with which type of cellular injury?
A. Coagulative Necrosis
B. Liquefactive Necrosis
C. Caseous Necrosis
D. Fibrinoid Necrosis
E. Fat Necrosis
Answer: B. Liquefactive Necrosis. ✓
Explanation: In the central nervous system, ischemic injury typically results in liquefactive
necrosis. This is characterized by the dissolution of tissue by potent lysosomal enzymes released
,from microglia and neutrophils, forming a liquid viscous mass. The hyperdense area on CT in this
clinical context is an acute hemorrhage, but the underlying necrotic process will be liquefactive.
Cardiovascular Pathology
6. A 55-year-old man presents with severe, crushing substernal chest pain radiating to his left
arm. ECG shows ST-segment elevations in the anterior leads. Serum troponin I is elevated. The
myocardial damage in this patient is best characterized by which of the following?
A. Apoptosis
B. Coagulative necrosis
C. Liquefactive necrosis
D. Caseous necrosis
E. Fibrinoid necrosis
Answer: B. Coagulative necrosis. ✓
Explanation: Myocardial infarction (MI) results in coagulative necrosis, the typical pattern of
ischemic cell death in solid organs (except the brain). It is characterized by preservation of the
basic tissue architecture for several days despite the death of the cells.
7. The gross appearance of the left ventricle in the patient from the previous question,
examined 3-4 days post-infarction, would most likely show which of the following?
A. No gross changes
B. A pale, firm, wedge-shaped area
C. A yellow, soft area with central liquefaction
D. A hyperemic border with a central yellow-tan softening
E. A white, scarred, fibrotic area
Answer: D. A hyperemic border with a central yellow-tan softening. ✓
*Explanation: At 3-4 days, the infarction is in the stage of necrosis and softening. The center
becomes yellow-tan and soft due to neutrophilic infiltration and enzymatic digestion, while the
surrounding area has a hyperemic border of inflammation.*
8. A 40-year-old woman presents with a butterfly rash on her face, arthralgias, and pleuritic
chest pain. Serologic testing is positive for anti-dsDNA antibodies. Which of the following
vascular lesions is most characteristic of this disease?
A. Atherosclerosis
B. Medial calcific sclerosis
C. Libman-Sacks endocarditis
D. Granulomatous vasculitis
E. Hyperplastic arteriolosclerosis
, Answer: C. Libman-Sacks endocarditis. ✓
Explanation: The patient has systemic lupus erythematosus (SLE). Libman-Sacks endocarditis is a
classic finding, characterized by non-bacterial verrucous endocarditis on the valve surfaces.
9. A 5-year-old boy presents with fever, conjunctival injection, a strawberry tongue, and a
desquamating rash on his palms and soles. An echocardiogram reveals aneurysms of the
coronary arteries. This condition is associated with pathology in which of the following blood
vessels?
A. Aorta
B. Large muscular arteries
C. Small arteries
D. Arterioles
E. Capillaries
Answer: B. Large muscular arteries. ✓
Explanation: This describes Kawasaki disease, which is an acute febrile illness of childhood
characterized by a systemic vasculitis that has a predilection for the coronary arteries, which are
large muscular arteries.
10. A 65-year-old man with a history of poorly controlled hypertension presents with a
sudden, severe "tearing" pain in his chest and back. His blood pressure is 180/110 mmHg in
the right arm and 150/90 mmHg in the left arm. The most likely diagnosis is a dissection
originating in the:
A. Ascending aorta (Type A)
B. Descending aorta (Type B)
C. Abdominal aorta
D. Aortic arch
E. Thoracic aorta distal to the left subclavian artery
Answer: A. Ascending aorta (Type A). ✓
Explanation: The classic presentation of an aortic dissection includes severe tearing pain and
blood pressure discrepancies between arms. A Type A dissection (involving the ascending aorta)
is a surgical emergency and can compromise the coronary arteries, aortic valve, and great
vessels, leading to the described blood pressure difference.
Pulmonary Pathology
11. A 60-year-old man with a 100-pack-year smoking history presents with a 2-cm solitary
pulmonary nodule in the periphery of the right upper lobe. A biopsy shows malignant cells
forming glands. This tumor is most likely:
A. Small cell carcinoma
