I85PREP
⌘ K
RANZCR Pathology study materials
RANZCR Pathology study resources

RANZCR Pathology practice questions

One question at a time. Build your RANZCR Pathology understanding.

First 50 of 200 questions. Each one lists the choices, the correct answer, and an explanation. The checker at the top of this page saves progress in this browser when it is available.

Continue in the practice tool above to load more questions, 50 at a time.

Question 1Pathology (general and systemic pathology relevant to clinical radiology)

Which cell type gives rise to the majority of primary malignant bone tumours in adults, including conventional osteosarcoma?

  1. Osteoblast lineage mesenchymal cells Correct answer.
  2. Chondrocytes of articular cartilage
  3. Synovial lining cells
  4. Plasma cells of the marrow

Explanation

Conventional osteosarcoma is a mesenchymal malignancy in which the neoplastic cells produce osteoid, reflecting osteoblastic differentiation. It is the commonest primary malignant bone tumour in young adults apart from myeloma in older patients. Synovial, chondroid and plasma cell tumours are separate entities with distinct lineages.

Question 2Pathology (general and systemic pathology relevant to clinical radiology)

A 55-year-old smoker has a central lung mass causing lobar collapse. Which histological feature most strongly indicates squamous cell carcinoma rather than adenocarcinoma?

  1. Intercellular bridges with keratin pearls Correct answer.
  2. Small blue cells with crush artefact
  3. Glandular acini with mucin production
  4. Papillary structures lined by hobnail cells

Explanation

Squamous cell carcinoma shows keratinisation, intercellular desmosomal bridges and often central necrosis giving keratin pearls. Adenocarcinoma instead forms glands and expresses mucin and TTF-1. Small cell carcinoma shows sheets of small cells with nuclear moulding, and hobnail papillary patterns suggest adenocarcinoma variants.

Question 3Pathology (general and systemic pathology relevant to clinical radiology)

Which feature best distinguishes a benign naevus from melanoma on histology?

  1. Infiltration of lymphocytes at the base
  2. Presence of melanin pigment
  3. Nests confined to the epidermis and upper dermis with maturation Correct answer.
  4. Uniformly high mitotic rate

Explanation

Benign melanocytic naevi show symmetrical, well-circumscribed nests that are confined to the epidermis and superficial dermis and that mature with depth. Melanoma shows asymmetry, poor circumscription, pagetoid spread and deep mitoses. Melanin and lymphocytes can be seen in both lesions.

Question 4Pathology (general and systemic pathology relevant to clinical radiology)

Which pattern of glomerular injury is characteristically produced by anti-glomerular basement membrane antibodies?

  1. Linear deposition of IgG along the basement membrane Correct answer.
  2. Segmental sclerosis with hyalinosis
  3. Mesangial IgA deposits
  4. Subepithelial humps on electron microscopy

Explanation

Anti-GBM antibodies bind uniformly to the glomerular basement membrane, giving smooth linear IgG immunofluorescence. This underlies Goodpasture disease with pulmonary haemorrhage and rapidly progressive glomerulonephritis. Subepithelial humps indicate post-infectious glomerulonephritis, and mesangial IgA indicates IgA nephropathy.

Question 5Pathology (general and systemic pathology relevant to clinical radiology)

Which microscopic finding is the hallmark of cirrhosis regardless of the underlying cause?

  1. Portal tract eosinophils with bile duct destruction
  2. Sinusoidal dilatation with congestion
  3. Regenerative nodules surrounded by fibrous septa Correct answer.
  4. Diffuse hepatocyte ballooning with Mallory bodies

Explanation

Cirrhosis is defined by bridging fibrosis that divides the liver into regenerative parenchymal nodules, distorting architecture and vasculature. Ballooning and Mallory bodies suggest steatohepatitis, duct destruction suggests primary biliary cholangitis, and congestion suggests outflow obstruction. These may coexist with cirrhosis but are not defining.

Question 6Pathology (general and systemic pathology relevant to clinical radiology)

Which organism is most commonly associated with gastric mucosa-associated lymphoid tissue lymphoma?

  1. Human herpesvirus 8
  2. Epstein-Barr virus
  3. Cytomegalovirus
  4. Helicobacter pylori Correct answer.

Explanation

Gastric MALT lymphoma usually arises from chronic Helicobacter pylori-driven lymphoid proliferation, and early lesions may regress with eradication therapy. Epstein-Barr virus is linked to Burkitt lymphoma and post-transplant lymphoproliferative disease, HHV8 to Kaposi sarcoma and primary effusion lymphoma.

Question 7Pathology (general and systemic pathology relevant to clinical radiology)

Which tumour is the most common benign primary cardiac neoplasm in adults?

  1. Lipoma
  2. Rhabdomyoma
  3. Myxoma Correct answer.
  4. Fibroma

Explanation

Cardiac myxoma is the commonest benign primary cardiac tumour in adults, typically arising in the left atrium and presenting with obstruction, embolism or constitutional symptoms. Rhabdomyoma is the commonest cardiac tumour in infants and is associated with tuberous sclerosis.

Question 8Pathology (general and systemic pathology relevant to clinical radiology)

Which histological pattern characterises papillary thyroid carcinoma?

  1. Sheets of small cells with salt-and-pepper chromatin
  2. Follicles containing abundant colloid with capsular invasion
  3. Solid sheets of uniform cells with amyloid stroma
  4. Papillae with optically clear nuclei and nuclear grooves Correct answer.

Explanation

Papillary thyroid carcinoma shows branching papillae lined by cells with optically clear Orphan Annie nuclei, nuclear grooves and pseudoinclusions. Amyloid stroma with uniform cells indicates medullary carcinoma, and capsular invasion indicates follicular carcinoma. Salt-and-pepper chromatin suggests a neuroendocrine or medullary lesion.

Question 9Pathology (general and systemic pathology relevant to clinical radiology)

A 62-year-old man has painless haematuria. Cystoscopy shows a papillary bladder lesion. Which histological type accounts for most bladder cancers in this setting?

  1. Squamous cell carcinoma
  2. Adenocarcinoma
  3. Small cell carcinoma
  4. Urothelial carcinoma Correct answer.

Explanation

Urothelial carcinoma accounts for the great majority of bladder cancers in regions without endemic schistosomiasis, and it commonly presents as a papillary lesion with painless haematuria. Squamous carcinoma is more frequent with chronic irritation or schistosomal infection, and adenocarcinoma is rare.

Question 10Pathology (general and systemic pathology relevant to clinical radiology)

A young woman has a unilateral ovarian mass showing a mixture of epithelial, mesenchymal and immature neural elements. What is the diagnosis?

  1. Krukenberg tumour
  2. Serous cystadenoma
  3. Immature teratoma Correct answer.
  4. Mature cystic teratoma

Explanation

Immature teratoma contains embryonic-type tissue, particularly primitive neuroepithelium, alongside other germ layer elements, and behaves as a malignant tumour graded by the amount of immature neural tissue. A mature cystic teratoma contains only well-differentiated adult tissues such as skin and hair.

Question 11Pathology (general and systemic pathology relevant to clinical radiology)

Which feature most reliably distinguishes a phyllodes tumour from a fibroadenoma of the breast?

  1. Lobular arrangement of acini
  2. Presence of both epithelial and stromal components
  3. Presence of apocrine metaplasia
  4. Leaf-like architecture with hypercellular stroma Correct answer.

Explanation

Phyllodes tumours show exaggerated intracanalicular growth producing leaf-like fronds with a hypercellular, often mitotically active stroma. Fibroadenomas also have epithelial and stromal elements but lack this striking stromal overgrowth. Apocrine metaplasia is a non-specific finding in fibrocystic change.

Question 12Pathology (general and systemic pathology relevant to clinical radiology)

A patient with long-standing Barrett oesophagus develops a distal oesophageal tumour. Which histological type is most likely?

  1. Small cell carcinoma
  2. Adenocarcinoma Correct answer.
  3. Leiomyosarcoma
  4. Squamous cell carcinoma

Explanation

Barrett oesophagus replaces squamous mucosa with intestinal-type columnar epithelium, which can progress through dysplasia to adenocarcinoma. Squamous cell carcinoma instead relates to smoking and alcohol and arises in the native squamous mucosa, often more proximally.

Question 13Pathology (general and systemic pathology relevant to clinical radiology)

A renal mass in an adult shows nests of cells with abundant clear cytoplasm, delicate vasculature and no significant atypia. Which tumour does this represent?

  1. Chromophobe renal cell carcinoma
  2. Oncocytoma
  3. Papillary renal cell carcinoma
  4. Clear cell renal cell carcinoma Correct answer.

Explanation

Clear cell renal cell carcinoma is composed of nests of cells with optically clear cytoplasm due to glycogen and lipid, supported by a delicate branching vascular network. Papillary tumours show papillary architecture, chromophobe tumours show pale cells with perinuclear halos, and oncocytomas show eosinophilic granular cells.

Question 14Pathology (general and systemic pathology relevant to clinical radiology)

Which serological marker is most useful in monitoring medullary thyroid carcinoma?

  1. Thyroid peroxidase antibody
  2. CA 19-9
  3. Calcitonin Correct answer.
  4. Thyroglobulin

Explanation

Medullary thyroid carcinoma arises from parafollicular C cells and secretes calcitonin, making serum calcitonin a sensitive marker of residual or recurrent disease. Thyroglobulin is used after treatment of differentiated follicular-derived carcinomas, and thyroid peroxidase antibodies indicate autoimmune thyroid disease.

Question 15Pathology (general and systemic pathology relevant to clinical radiology)

A colonic polyp shows dysplastic epithelium extending into the submucosa through the muscularis mucosae without invasion of the deeper bowel wall. What is this lesion?

  1. Adenoma with intramucosal carcinoma
  2. Serrated adenoma without dysplasia
  3. Adenoma with submucosal invasive carcinoma Correct answer.
  4. Hyperplastic polyp

Explanation

Once dysplastic glands breach the muscularis mucosae and enter submucosa, the lesion is an invasive carcinoma, and this determines the risk of lymph node metastasis and the need for resection. Intramucosal carcinoma stays within the lamina propria above the muscularis mucosae and has negligible metastatic potential.

Question 16Pathology (general and systemic pathology relevant to clinical radiology)

Which pathological process best explains the development of a cerebral abscess following suppurative lung disease?

  1. Primary viral infection of neurones
  2. Haematogenous embolisation of infected material Correct answer.
  3. Retrograde axonal transport of bacteria
  4. Direct spread through the meninges

Explanation

Septic emboli from a pulmonary source lodge in cerebral vessels, producing infected infarction and subsequent abscess formation, often at the grey-white junction. Direct meningeal spread and axonal transport do not explain haematogenous abscesses, and viral infection produces encephalitis rather than a purulent collection.

Question 17Pathology (general and systemic pathology relevant to clinical radiology)

Which histological finding is characteristic of a rheumatoid nodule?

  1. Non-caseating granuloma with asteroid bodies
  2. Caseating granuloma with acid-fast bacilli
  3. Amyloid deposition with giant cell reaction
  4. Central fibrinoid necrosis surrounded by palisading histiocytes Correct answer.

Explanation

Rheumatoid nodules show a centre of fibrinoid necrosis rimmed by palisading macrophages and lymphocytes, usually in subcutaneous tissue over pressure points. Caseation with acid-fast bacilli indicates tuberculosis, and asteroid bodies within granulomas suggest sarcoidosis.

Question 18Pathology (general and systemic pathology relevant to clinical radiology)

A patient with chronic hepatitis B develops a liver mass. Which histological feature suggests hepatocellular carcinoma rather than a benign regenerative nodule?

  1. Steatosis without cytological atypia
  2. Periportal fibrosis only
  3. Portal tract inflammation with interface hepatitis
  4. Trabecular architecture with thickened plates and vascular invasion Correct answer.

Explanation

Hepatocellular carcinoma shows trabeculae more than a few cells thick, loss of reticulin framework, cytological atypia and vascular invasion. Regenerative nodules retain a normal reticulin network and do not invade vessels. Inflammation, steatosis and fibrosis are non-specific and can occur without malignancy.

Question 19Pathology (general and systemic pathology relevant to clinical radiology)

Which feature is most typical of a benign prostatic hyperplasia nodule on histology?

  1. Crowded small glands with prominent nucleoli
  2. Perineural invasion by atypical glands
  3. Proliferation of glands and stroma with a double cell layer Correct answer.
  4. Solid sheets of cells with necrosis

Explanation

Benign prostatic hyperplasia consists of hyperplastic glands and fibromuscular stroma, and the glands retain a basal cell layer that can be shown with high molecular weight cytokeratin or p63. Prostate carcinoma shows crowded glands lacking basal cells, prominent nucleoli, perineural invasion and necrosis.

Question 20Pathology (general and systemic pathology relevant to clinical radiology)

Which histological pattern is characteristic of membranous nephropathy?

  1. Subendothelial deposits with tram-track duplication
  2. Crescents filling Bowman space
  3. Subepithelial immune complex deposits with basement membrane spikes Correct answer.
  4. Mesangial proliferation with C3 deposition

Explanation

Membranous nephropathy produces subepithelial immune complex deposits, often against the phospholipase A2 receptor, with basement membrane spikes on silver stain. Subendothelial deposits with tram-tracking indicate membranoproliferative glomerulonephritis, and crescents indicate rapidly progressive disease.

Question 21Pathology (general and systemic pathology relevant to clinical radiology)

A patient with a history of treated melanoma presents with a pigmented brain lesion at the grey-white junction. Which feature best supports metastatic melanoma over a primary brain tumour?

  1. Rosettes with true ependymal canals
  2. Rosenthal fibres and eosinophilic granular bodies
  3. Pseudopalisading necrosis with microvascular proliferation
  4. Pleomorphic cells containing melanin pigment Correct answer.

Explanation

Metastatic melanoma contains pleomorphic cells with melanin pigment and typically sits at the grey-white junction where haematogenous emboli lodge. Rosenthal fibres suggest pilocytic astrocytoma, pseudopalisading necrosis suggests glioblastoma, and true rosettes suggest ependymoma.

Question 22Pathology (general and systemic pathology relevant to clinical radiology)

Which mechanism best explains the increased risk of adenocarcinoma in chronic atrophic gastritis with intestinal metaplasia?

  1. Bile reflux causing acute erosions
  2. Direct mucosal invasion by Helicobacter pylori
  3. Autoimmune destruction of parietal cells alone
  4. Progressive accumulation of genetic alterations in metaplastic epithelium Correct answer.

Explanation

Intestinal metaplasia is a precursor lesion in which chronic inflammation drives cumulative genetic and epigenetic alterations, including TP53 and CDH1 changes, culminating in carcinoma. Helicobacter pylori acts as an initiating carcinogen but does not invade mucosa directly, and parietal cell loss alone does not cause cancer.

Question 23Pathology (general and systemic pathology relevant to clinical radiology)

A lung biopsy shows a proliferation of atypical spindle cells with fascicular growth, focal necrosis and a high mitotic count in a patient with no smoking history. Which diagnosis is most consistent?

  1. Inflammatory myofibroblastic tumour
  2. Pleomorphic sarcoma of the lung Correct answer.
  3. Organising pneumonia
  4. Pulmonary hamartoma

Explanation

A high-grade spindle cell neoplasm with fascicles, marked atypia, necrosis and frequent mitoses indicates a primary pulmonary sarcoma, of which pleomorphic sarcoma is a recognised type. Hamartomas contain cartilage and fat without atypia, inflammatory myofibroblastic tumours show myofibroblasts with inflammation, and organising pneumonia shows fibroblastic plugs in airspaces.

Question 24Pathology (general and systemic pathology relevant to clinical radiology)

Which molecular alteration is most characteristic of follicular carcinoma of the thyroid?

  1. RET proto-oncogene point mutation
  2. BRAF V600E point mutation
  3. MEN1 gene deletion
  4. PAX8-PPARG rearrangement Correct answer.

Explanation

Follicular thyroid carcinoma frequently harbours a PAX8-PPARG translocation or RAS mutations, whereas papillary carcinoma is associated with BRAF V600E or RET-PTC rearrangements. RET point mutations underlie hereditary medullary carcinoma in MEN2, and MEN1 deletion causes pituitary, parathyroid and pancreatic tumours.

Question 25Pathology (general and systemic pathology relevant to clinical radiology)

A colonic tumour shows loss of nuclear staining for mismatch repair proteins MLH1 and PMS2, with BRAF V600E mutation and MLH1 promoter hypermethylation. What does this pattern indicate?

  1. Lynch syndrome due to a germline MLH1 mutation
  2. Germline PMS2 mutation with intact MLH1
  3. Normal mismatch repair function
  4. Sporadic mismatch repair deficiency with the CpG island methylator phenotype Correct answer.

Explanation

Combined loss of MLH1 and PMS2 can reflect either a germline MLH1 defect or somatic MLH1 silencing. The presence of BRAF V600E and MLH1 promoter hypermethylation strongly favours a sporadic, methylator-phenotype pathway rather than Lynch syndrome, so germline testing is usually unnecessary.

Question 26Pathology (general and systemic pathology relevant to clinical radiology)

Which cell type is the principal component of a glioblastoma multiforme?

  1. Atypical astrocytes Correct answer.
  2. Schwann cells
  3. Ependymal cells
  4. Oligodendrocytes

Explanation

Glioblastoma is a high-grade astrocytic tumour, so the neoplastic population is composed of pleomorphic, atypical astrocytes with necrosis and microvascular proliferation. Ependymal, Schwann and oligodendroglial cells give rise to other tumour types with different histology and behaviour.

Question 27Pathology (general and systemic pathology relevant to clinical radiology)

Which pathological feature best defines a malignant tumour rather than a benign one?

  1. Uniform cellular appearance
  2. Slow growth over many years
  3. Capsule formation
  4. Metastasis to distant sites Correct answer.

Explanation

Metastasis is the single feature that unequivocally establishes malignancy, because it demonstrates the capacity to disseminate and implant at distant sites. Benign tumours may be encapsulated, slow-growing and cytologically bland, so none of these features excludes malignancy on its own.

Question 28Pathology (general and systemic pathology relevant to clinical radiology)

Which type of necrosis is characteristically seen in the centre of a tuberculous granuloma?

  1. Fat necrosis
  2. Caseous necrosis Correct answer.
  3. Coagulative necrosis
  4. Fibrinoid necrosis

Explanation

Caseous necrosis is the cheeselike, structureless necrosis found centrally in tuberculosis granulomas, reflecting a combination of cell death and incomplete enzymatic digestion. Coagulative, fibrinoid and fat necrosis each occur in different characteristic settings.

Question 29Pathology (general and systemic pathology relevant to clinical radiology)

Which immunoglobulin class is produced first in a primary humoral immune response?

  1. IgE
  2. IgG
  3. IgA
  4. IgM Correct answer.

Explanation

Naive B cells express surface IgM, so IgM is the first antibody class secreted after initial antigen exposure, before class switching occurs. IgG dominates secondary responses, while IgA and IgE are produced after specific class switching.

Question 30Pathology (general and systemic pathology relevant to clinical radiology)

Which histological change is the hallmark of reversible acute cell injury?

  1. Enzymatic fat necrosis
  2. Nuclear fragmentation
  3. Cellular swelling with vacuolar change Correct answer.
  4. Karyolysis

Explanation

Hydropic swelling from failure of the ATP-dependent sodium pump is the classic reversible change of acute cell injury and resolves if the insult is removed. Nuclear fragmentation and karyolysis are features of irreversible injury and necrosis.

Question 31Pathology (general and systemic pathology relevant to clinical radiology)

Which organism most commonly causes lobar pneumonia in adults?

  1. Mycoplasma pneumoniae
  2. Pseudomonas aeruginosa
  3. Staphylococcus aureus
  4. Streptococcus pneumoniae Correct answer.

Explanation

Streptococcus pneumoniae is the leading cause of community-acquired lobar pneumonia, producing the classic four-stage exudative consolidation. The other organisms more often cause bronchopneumonia, atypical interstitial patterns or hospital-acquired infection.

Question 32Pathology (general and systemic pathology relevant to clinical radiology)

Which feature is characteristic of a well-differentiated squamous cell carcinoma?

  1. Papillary fronds lined by clear cells
  2. Glandular acini with mucin production
  3. Keratin pearls and intercellular bridges Correct answer.
  4. Small round blue cells with rosettes

Explanation

Squamous differentiation is recognised by keratinisation, which forms keratin pearls, and by desmosomal attachments visible as intercellular bridges. Glandular, small blue cell and papillary clear cell patterns indicate other tumour types.

Question 33Pathology (general and systemic pathology relevant to clinical radiology)

Which process describes the reversible replacement of one mature epithelial type by another?

  1. Anaplasia
  2. Hyperplasia
  3. Dysplasia
  4. Metaplasia Correct answer.

Explanation

Metaplasia is the reversible substitution of one differentiated cell type for another, typically as an adaptive response to chronic irritation, such as squamous metaplasia of the bronchial epithelium. Dysplasia, anaplasia and hyperplasia describe disordered growth, loss of differentiation and increased cell number respectively.

Question 34Pathology (general and systemic pathology relevant to clinical radiology)

A 55-year-old woman has a renal mass with a translocation involving the TFE3 gene. Which diagnosis is most likely?

  1. Papillary renal cell carcinoma
  2. Xp11 translocation renal cell carcinoma Correct answer.
  3. Clear cell renal cell carcinoma
  4. Chromophobe renal cell carcinoma

Explanation

TFE3 translocations, usually t(X;1), define Xp11 translocation renal cell carcinoma, which shows papillary and nested architecture with clear to eosinophilic cells. Clear cell, papillary and chromophobe carcinomas are defined by other genetic and histological features.

Question 35Pathology (general and systemic pathology relevant to clinical radiology)

A breast biopsy shows a proliferation of uniform cells filling and distending ducts, with a preserved myoepithelial layer and no necrosis. Which lesion is most likely?

  1. Invasive ductal carcinoma
  2. Ductal carcinoma in situ
  3. Usual ductal hyperplasia Correct answer.
  4. Lobular carcinoma in situ

Explanation

Usual ductal hyperplasia shows a heterogeneous, streaming proliferation within ducts with retained myoepithelial cells and no necrosis, distinguishing it from in situ carcinoma. Ductal carcinoma in situ shows monomorphic cells with necrosis and expanded ducts, while invasive carcinoma breaches the basement membrane.

Question 36Pathology (general and systemic pathology relevant to clinical radiology)

A liver biopsy shows portal tracts expanded by lymphocytes, interface hepatitis and bridging fibrosis. Which diagnosis is most likely?

  1. Chronic hepatitis C Correct answer.
  2. Primary biliary cholangitis
  3. Alcoholic steatohepatitis
  4. Hepatic adenoma

Explanation

Chronic viral hepatitis, including hepatitis C, characteristically produces portal lymphocytic inflammation, interface hepatitis and progressive bridging fibrosis. Alcoholic steatohepatitis shows steatosis and Mallory-Denk bodies, while primary biliary cholangitis targets bile ducts.

Question 37Pathology (general and systemic pathology relevant to clinical radiology)

Which finding on a peripheral blood film is most characteristic of chronic myeloid leukaemia?

  1. Marked eosinophilia with Charcot-Leyden crystals
  2. Numerous smudge cells with mature lymphocytes
  3. Predominance of lymphoblasts
  4. A full spectrum of myeloid precursors including myelocytes and metamyelocytes Correct answer.

Explanation

Chronic myeloid leukaemia produces a left-shifted myeloid leucocytosis in which mature and immature granulocytes at all stages are present, reflecting clonal proliferation with the BCR-ABL1 fusion. Lymphoblast predominance, eosinophilia and smudge cells indicate other haematological disorders.

Question 38Pathology (general and systemic pathology relevant to clinical radiology)

A 30-year-old man has a testicular mass with uniform cells containing glycogen-rich clear cytoplasm, arranged in nests separated by fibrous septa with lymphocytic infiltrate. Which diagnosis is most likely?

  1. Leydig cell tumour
  2. Seminoma Correct answer.
  3. Embryonal carcinoma
  4. Yolk sac tumour

Explanation

Seminoma characteristically shows uniform cells with clear glycogen-rich cytoplasm and prominent nucleoli, divided by fibrous septa containing lymphocytes. Yolk sac tumour, embryonal carcinoma and Leydig cell tumour each show different distinctive patterns.

Question 39Pathology (general and systemic pathology relevant to clinical radiology)

Which feature most strongly favours a benign melanocytic naevus over melanoma?

  1. Nuclear pleomorphism with prominent nucleoli
  2. Asymmetric silhouette with poor circumscription
  3. Mitoses in the dermal component
  4. Uniform nests that mature with depth Correct answer.

Explanation

Benign naevi show symmetrical, well-demarcated nests whose cells become smaller and more uniform deeper in the lesion, a process termed maturation. Melanoma instead shows poor circumscription, cytological atypia and dermal mitoses.

Question 40Pathology (general and systemic pathology relevant to clinical radiology)

A patient with a long-standing duodenal ulcer develops a perforation. Which layer is breached first as the ulcer deepens?

  1. Muscularis propria
  2. Submucosa
  3. Mucosa Correct answer.
  4. Serosa

Explanation

Peptic ulcers begin in the mucosa and deepen progressively through submucosa and muscularis propria before reaching the serosa, so the mucosa is breached first. Full-thickness perforation into the peritoneal cavity occurs once all layers, including serosa, are destroyed.

Question 41Pathology (general and systemic pathology relevant to clinical radiology)

Which pathological change underlies the nephrotic syndrome in minimal change disease?

  1. Diffuse foot process effacement on electron microscopy Correct answer.
  2. Subepithelial immune complex deposits
  3. Segmental sclerosis of glomerular tufts
  4. Mesangial IgA deposition

Explanation

Minimal change disease shows normal glomeruli on light microscopy but diffuse effacement of podocyte foot processes on electron microscopy, reflecting podocyte injury and causing heavy proteinuria. Immune deposits, segmental sclerosis and mesangial IgA define other glomerular diseases.

Question 42Pathology (general and systemic pathology relevant to clinical radiology)

A thyroid nodule shows follicles with capsular and vascular invasion but no nuclear features of papillary carcinoma. Which diagnosis is most likely?

  1. Medullary carcinoma
  2. Papillary carcinoma
  3. Follicular adenoma
  4. Follicular carcinoma Correct answer.

Explanation

Follicular carcinoma is diagnosed by capsular and vascular invasion in a follicular-patterned tumour lacking papillary nuclear features. Follicular adenoma lacks invasion, while papillary and medullary carcinomas have distinct nuclear and neuroendocrine features.

Question 43Pathology (general and systemic pathology relevant to clinical radiology)

Which arterial change is the primary lesion of atherosclerosis?

  1. Intimal accumulation of lipid-laden macrophages and smooth muscle forming a plaque Correct answer.
  2. Fibrinoid necrosis of arterioles
  3. Hyaline thickening of arterioles
  4. Segmental transmural granulomatous inflammation

Explanation

Atherosclerosis begins with endothelial injury and intimal accumulation of lipid-laden macrophages and smooth muscle cells, producing a fibrofatty plaque. Fibrinoid and hyaline arteriolosclerosis affect small vessels, and granulomatous inflammation suggests arteritis.

Question 44Pathology (general and systemic pathology relevant to clinical radiology)

A lung biopsy from an asbestos-exposed worker shows golden-brown, iron-coated rod-shaped structures in alveolar macrophages. What are these called?

  1. Psammoma bodies
  2. Negri bodies
  3. Ferruginous bodies Correct answer.
  4. Aschoff bodies

Explanation

Asbestos fibres become coated with iron and protein to form ferruginous bodies, which appear as golden-brown beaded rods in macrophages and are a marker of asbestos exposure. Psammoma, Aschoff and Negri bodies are seen in unrelated conditions.

Question 45Pathology (general and systemic pathology relevant to clinical radiology)

A 68-year-old smoker has a lung tumour showing small cells with scant cytoplasm, nuclear moulding and frequent mitoses. Which feature most strongly supports a neuroendocrine origin?

  1. Glandular acini
  2. Salt-and-pepper chromatin Correct answer.
  3. Keratin pearls
  4. Mucin vacuoles

Explanation

Small cell carcinoma shows finely granular salt-and-pepper chromatin, nuclear moulding and neuroendocrine markers such as synaptophysin and chromogranin. Keratin pearls, mucin vacuoles and glandular acini indicate squamous or glandular differentiation instead.

Question 46Pathology (general and systemic pathology relevant to clinical radiology)

Which histological pattern best characterises a schwannoma?

  1. Rosettes around blood vessels
  2. Palisading granulomas with giant cells
  3. Antoni A and Antoni B areas with Verocay bodies Correct answer.
  4. Whorls of meningothelial cells with psammoma bodies

Explanation

Schwannomas show alternating dense Antoni A areas with Verocay bodies and loose myxoid Antoni B areas, reflecting Schwann cell proliferation. Perivascular rosettes, meningothelial whorls and granulomas indicate ependymoma, meningioma and granulomatous disease respectively.

Question 47Pathology (general and systemic pathology relevant to clinical radiology)

A patient with a known primary carcinoma develops a solitary adrenal mass. Which finding on needle biopsy would most strongly suggest metastasis rather than adrenocortical adenoma?

  1. Uniform cells with low nuclear-to-cytoplasmic ratio
  2. Nuclear atypia with necrosis and vascular invasion Correct answer.
  3. Fibrous capsule surrounding the lesion
  4. Lipid-rich cells in nests

Explanation

Metastatic carcinoma in the adrenal shows cytological atypia, necrosis and vascular invasion, often with histological resemblance to the primary tumour. Adrenocortical adenomas consist of uniform lipid-rich cells without necrosis or vascular invasion.

Question 48Pathology (general and systemic pathology relevant to clinical radiology)

In the development of invasive cervical squamous cell carcinoma, which step immediately precedes invasion?

  1. High-grade squamous intraepithelial lesion Correct answer.
  2. Chronic cervicitis
  3. Endocervical glandular dysplasia
  4. Low-grade squamous intraepithelial lesion

Explanation

Invasive squamous carcinoma arises from a high-grade squamous intraepithelial lesion, in which full-thickness dysplasia is confined by the basement membrane before invasion begins. Low-grade lesions often regress, and glandular dysplasia leads to adenocarcinoma.

Question 49Pathology (general and systemic pathology relevant to clinical radiology)

A 24-year-old man has a mediastinal mass showing lymphocytes intermingled with large cells that have prominent nucleoli and CD15/CD30 positivity. Which diagnosis is most likely?

  1. Classic Hodgkin lymphoma Correct answer.
  2. Lymphoblastic lymphoma
  3. Nodular lymphocyte-predominant Hodgkin lymphoma
  4. Diffuse large B-cell lymphoma

Explanation

Classic Hodgkin lymphoma features Reed-Sternberg cells that are CD15 and CD30 positive within a reactive inflammatory background, often presenting as a mediastinal mass in young adults. Nodular lymphocyte-predominant disease lacks CD15/CD30, and the other lymphomas differ in cytology and immunophenotype.

Question 50Pathology (general and systemic pathology relevant to clinical radiology)

Which mechanism best explains the increased risk of colorectal carcinoma in long-standing ulcerative colitis?

  1. Chronic inflammation driving repeated epithelial injury and dysplasia Correct answer.
  2. Ischaemic infarction of the colonic mucosa
  3. Direct viral transformation of colonocytes
  4. Bile acid reflux causing squamous metaplasia

Explanation

Chronic mucosal inflammation in ulcerative colitis causes repeated cycles of epithelial injury and regeneration, accumulating genetic alterations that progress through dysplasia to carcinoma. Viral transformation, squamous metaplasia and infarction are not the mechanisms involved.