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Arab Board Oncology Clinical study materials
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Arab Board Oncology Clinical practice questions

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Question 1General Oncology and Principles of Cancer Biology

Which cellular process is most directly responsible for the uncontrolled proliferation characteristic of malignant neoplasms?

  1. Disruption of the normal cell cycle checkpoints Correct answer.
  2. Increased rate of apoptosis
  3. Enhanced DNA repair fidelity
  4. Reduced telomerase activity

Explanation

Malignant cells accumulate mutations that disable cell cycle checkpoints such as G1/S and G2/M, allowing continued division despite damage. Loss of these safeguards is a hallmark of carcinogenesis, whereas apoptosis and repair fidelity are protective mechanisms.

Question 2General Oncology and Principles of Cancer Biology

A tumor suppressor gene is best characterized by which behavior when both alleles are inactivated?

  1. Conversion into a fusion oncogene
  2. Loss of a braking function that restrains growth Correct answer.
  3. Acquisition of drug resistance
  4. Oncogenic activation through gain of function

Explanation

Tumor suppressor genes normally restrain proliferation or promote repair and apoptosis; their loss of function permits growth. The classic two-hit model requires inactivation of both alleles for the phenotype to emerge.

Question 3General Oncology and Principles of Cancer Biology

Which term describes the ability of a malignant tumor to invade local tissue and spread to distant sites?

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

Explanation

Metastasis is the process by which tumor cells disseminate from the primary site and establish growth at distant organs. It is a defining feature of malignancy and a major cause of cancer mortality.

Question 4General Oncology and Principles of Cancer Biology

In the context of cancer biology, what is the significance of a driver mutation?

  1. It prevents clonal expansion
  2. It only affects germline inheritance
  3. It confers a selective growth advantage to the cancer cell Correct answer.
  4. It is always a harmless passenger alteration

Explanation

Driver mutations provide a fitness advantage that promotes clonal expansion and tumor development. Passenger mutations are incidental and do not confer such advantage.

Question 5General Oncology and Principles of Cancer Biology

Which feature distinguishes benign from malignant tumors most reliably?

  1. Presence of a capsule
  2. Rate of growth
  3. Degree of cellular differentiation
  4. Capacity for metastatic spread Correct answer.

Explanation

The ability to metastasize is the most reliable discriminator of malignancy, as benign tumors remain localized. Growth rate and differentiation can overlap between benign and malignant lesions.

Question 6General Oncology and Principles of Cancer Biology

A patient's tumor shows high microsatellite instability with loss of mismatch repair protein expression. Which biological consequence most directly underlies this finding?

  1. Increased chromosomal translocation frequency
  2. Defective nucleotide excision repair
  3. Impaired detection and correction of DNA replication errors Correct answer.
  4. Enhanced homologous recombination

Explanation

Mismatch repair corrects base-base mismatches and small insertion-deletion loops arising during replication; its loss produces microsatellite instability. This is distinct from nucleotide excision repair or homologous recombination defects.

Question 7General Oncology and Principles of Cancer Biology

Which of the following best explains why tumors require angiogenesis for growth beyond a few millimeters?

  1. To evade immune surveillance
  2. To activate oncogenes
  3. To supply oxygen and nutrients by diffusion limitation Correct answer.
  4. To increase mutation rate

Explanation

Without new blood vessels, tumors are limited by diffusion to approximately 1-2 mm because oxygen and nutrients cannot reach deeper cells. Angiogenesis overcomes this limitation and supports continued growth.

Question 8General Oncology and Principles of Cancer Biology

Which cellular process is most closely associated with the concept of replicative immortality in cancer cells?

  1. Increased apoptosis
  2. Enhanced contact inhibition
  3. Reduced growth factor signaling
  4. Activation of telomerase Correct answer.

Explanation

Telomerase maintains telomere length, allowing cancer cells to bypass replicative senescence and divide indefinitely. This is a recognized hallmark of cancer.

Question 9General Oncology and Principles of Cancer Biology

A tumor suppressor protein that senses DNA damage and halts the cell cycle to allow repair is best exemplified by which molecule?

  1. TP53 Correct answer.
  2. MYC
  3. BCR-ABL
  4. RAS

Explanation

TP53 encodes p53, which induces cell cycle arrest or apoptosis in response to DNA damage. RAS, MYC, and BCR-ABL are oncogenic drivers rather than damage-sensing tumor suppressors.

Question 10General Oncology and Principles of Cancer Biology

Which mechanism best describes the role of oncogenes in carcinogenesis?

  1. Silencing by promoter methylation
  2. Recessive loss of both alleles
  3. Defective DNA repair
  4. Dominant gain-of-function promoting proliferation Correct answer.

Explanation

Oncogenes act dominantly; a single activating mutation in one allele can drive proliferation. This contrasts with tumor suppressors, which typically require biallelic inactivation.

Question 11General Oncology and Principles of Cancer Biology

In the multistep model of colorectal carcinogenesis, which sequence most accurately reflects the typical progression?

  1. Normal epithelium to adenoma to carcinoma with sequential genetic alterations Correct answer.
  2. Normal epithelium to carcinoma without intermediate lesions
  3. Adenoma to normal epithelium to carcinoma
  4. Carcinoma to adenoma to normal epithelium

Explanation

The adenoma-carcinoma sequence involves accumulation of mutations including APC, KRAS, and TP53 across progressive lesions. This illustrates the multistep nature of carcinogenesis.

Question 12General Oncology and Principles of Cancer Biology

Which hallmark of cancer describes the ability of tumor cells to evade programmed cell death?

  1. Inducing angiogenesis
  2. Sustaining proliferative signaling
  3. Genome instability
  4. Resisting apoptosis Correct answer.

Explanation

Evading apoptosis allows malignant cells to survive despite genetic damage or stress signals. This is a distinct hallmark from angiogenesis or proliferative signaling.

Question 13General Oncology and Principles of Cancer Biology

A tumor cell acquires the ability to invade basement membrane and enter the bloodstream. Which step of the metastatic cascade does this represent?

  1. Angiogenesis
  2. Colonization
  3. Intravasation Correct answer.
  4. Dormancy

Explanation

Intravasation is the entry of tumor cells into the vasculature or lymphatics after invading surrounding tissue. Colonization occurs later at the distant site.

Question 14General Oncology and Principles of Cancer Biology

Which statement best explains the concept of synthetic lethality exploited in cancer therapy?

  1. Mutations in two genes always cause cancer
  2. Two genes each individually essential for survival
  3. Loss of one gene renders the cell dependent on a second pathway, so inhibiting it kills the cell Correct answer.
  4. Combining two drugs always produces additive toxicity

Explanation

Synthetic lethality occurs when loss of one gene is tolerated but combined loss of a second pathway is lethal, as with BRCA-mutant tumors and PARP inhibition. This principle enables selective targeting of tumor-specific defects.

Question 15General Oncology and Principles of Cancer Biology

Which of the following best characterizes the Warburg effect observed in many tumors?

  1. Exclusive reliance on fatty acid oxidation
  2. Aerobic glycolysis producing lactate even in the presence of oxygen Correct answer.
  3. Complete absence of glucose metabolism
  4. Enhanced oxidative phosphorylation with suppressed glycolysis

Explanation

The Warburg effect describes a shift toward aerobic glycolysis, where tumors convert glucose to lactate despite adequate oxygen. This supports biosynthetic demands and is exploited in FDG-PET imaging.

Question 16General Oncology and Principles of Cancer Biology

Which biological property of a monoclonal antibody such as trastuzumab underlies its antitumor activity against HER2-overexpressing breast cancer?

  1. Inhibition of topoisomerase II
  2. Depletion of folate cofactors
  3. Direct inhibition of HER2 signaling and antibody-dependent cellular cytotoxicity Correct answer.
  4. Nonspecific alkylation of DNA

Explanation

Trastuzumab binds HER2, blocking downstream signaling and engaging immune effector mechanisms such as antibody-dependent cellular cytotoxicity. This is distinct from cytotoxic chemotherapy mechanisms.

Question 17Cancer Epidemiology, Prevention, and Screening

Which measure expresses the proportion of a population that has a disease at a given point in time?

  1. Case fatality rate
  2. Point prevalence Correct answer.
  3. Relative risk
  4. Incidence rate

Explanation

Prevalence counts all existing cases (new and old) in a population at a defined moment or period, expressed as a proportion. Incidence measures new cases over time, while case fatality and relative risk describe outcomes and comparisons rather than burden of existing disease.

Question 18Cancer Epidemiology, Prevention, and Screening

A screening test for colorectal cancer has high sensitivity but low specificity. What is the most likely consequence in the screened population?

  1. Reduced positive predictive value only in high-prevalence groups
  2. No effect on the number of false results
  3. Many false negatives missed at screening
  4. Many false positives requiring follow-up colonoscopy Correct answer.

Explanation

High sensitivity means few true cases are missed, but low specificity means many people without disease test positive. These false positives generate unnecessary confirmatory tests and anxiety. Positive predictive value falls when prevalence is low, not high.

Question 19Cancer Epidemiology, Prevention, and Screening

Which infection is the leading infectious cause of cancer worldwide, accounting for cancers of the cervix, anus, and oropharynx?

  1. Helicobacter pylori
  2. Human papillomavirus Correct answer.
  3. Epstein-Barr virus
  4. Hepatitis B virus

Explanation

Human papillomavirus is the principal infectious cause of cervical cancer and is also linked to anal and oropharyngeal cancers. Hepatitis B causes hepatocellular carcinoma, Epstein-Barr virus is linked to Burkitt and nasopharyngeal cancers, and H. pylori causes gastric cancer and lymphoma.

Question 20Cancer Epidemiology, Prevention, and Screening

In a cohort study, the incidence of lung cancer among smokers is 60 per 100,000 person-years and among non-smokers is 10 per 100,000 person-years. What is the attributable risk in the exposed?

  1. 70 per 100,000 person-years
  2. 50 per 100,000 person-years Correct answer.
  3. 6 per 100,000 person-years
  4. 10 per 100,000 person-years

Explanation

Attributable risk in the exposed is the difference in incidence between exposed and unexposed groups: 60 minus 10 equals 50 per 100,000 person-years. This represents the excess incidence attributable to smoking. The ratio (6) is the relative risk, not the attributable risk.

Question 21Cancer Epidemiology, Prevention, and Screening

Which of the following is the most established modifiable risk factor for hepatocellular carcinoma?

  1. Aflatoxin-free diet
  2. Chronic hepatitis C infection Correct answer.
  3. Regular physical activity
  4. Cigarette smoking

Explanation

Chronic hepatitis C (and chronic hepatitis B) infection is a well-established major risk factor for hepatocellular carcinoma through chronic inflammation and cirrhosis. Physical activity is protective rather than causative, and an aflatoxin-free diet prevents rather than causes disease.

Question 22Cancer Epidemiology, Prevention, and Screening

A national program offers mammography to women aged 50 to 69 years every two years. Which outcome is the most direct measure of the program's screening performance?

  1. Breast cancer mortality in the whole population
  2. Overall five-year survival of all breast cancer patients
  3. Proportion of screen-detected cancers that are early stage Correct answer.
  4. Total number of mastectomies performed

Explanation

The stage distribution of screen-detected cancers directly reflects whether screening is finding disease early, which is the proximate aim. Mortality is the ultimate outcome but is influenced by treatment and takes years to accrue. Survival can be inflated by lead-time and length bias, and mastectomy counts reflect treatment patterns.

Question 23Cancer Epidemiology, Prevention, and Screening

Which cancer is the most common malignancy in men worldwide when both sexes are considered separately?

  1. Colorectal cancer
  2. Prostate cancer
  3. Stomach cancer
  4. Lung cancer Correct answer.

Explanation

Lung cancer remains the most commonly diagnosed cancer and leading cause of cancer death worldwide in men. Prostate cancer is common in high-income regions but less frequent globally, and colorectal and stomach cancers rank lower in incidence.

Question 24Cancer Epidemiology, Prevention, and Screening

Which primary prevention strategy is most effective for reducing cervical cancer incidence at the population level?

  1. Screening starting at age 40
  2. Annual Pap smear screening
  3. HPV vaccination of adolescent girls Correct answer.
  4. Colposcopy for all women

Explanation

HPV vaccination prevents persistent infection with oncogenic HPV types and thus prevents the precursor lesions that lead to cervical cancer, making it a primary prevention measure. Screening detects existing precancer or cancer and is secondary prevention. Colposcopy is a diagnostic procedure, not a population prevention strategy.

Question 25Cancer Epidemiology, Prevention, and Screening

A case-control study finds an odds ratio of 2.5 linking a dietary factor to gastric cancer, with a 95% confidence interval of 1.2 to 5.0. How should this result be interpreted?

  1. The study proves causation
  2. The association is statistically significant at the 5% level Correct answer.
  3. The result is invalid because odds ratios cannot exceed 2
  4. The association is not statistically significant

Explanation

A 95% confidence interval that excludes 1.0 indicates a statistically significant association at the 5% level. Statistical significance does not establish causation, which requires consideration of bias, confounding, temporality, and biologic plausibility. Odds ratios can take any positive value.

Question 26Cancer Epidemiology, Prevention, and Screening

Which of the following best describes the purpose of a cancer registry?

  1. To determine individual patient prognosis
  2. To provide systematic data on cancer incidence, treatment, and outcomes Correct answer.
  3. To deliver chemotherapy to registered patients
  4. To replace pathology reporting

Explanation

Population-based cancer registries systematically collect data on incidence, stage, treatment, and survival to inform planning, research, and evaluation. They are not clinical service providers and do not replace diagnostic reporting or predict individual outcomes.

Question 27Cancer Epidemiology, Prevention, and Screening

Which screening modality is recommended for average-risk adults aged 50 to 75 years for colorectal cancer?

  1. Annual serum CEA measurement
  2. Colonoscopy every 10 years or annual fecal immunochemical testing Correct answer.
  3. Annual abdominal ultrasound
  4. CT colonography every 15 years

Explanation

Average-risk colorectal cancer screening options include colonoscopy every 10 years or annual fecal immunochemical testing, among others. Serum CEA is a tumor marker used in monitoring, not screening, and ultrasound does not visualize the colon adequately.

Question 28Cancer Epidemiology, Prevention, and Screening

Lead-time bias in cancer screening refers to which phenomenon?

  1. Apparent survival prolongation due to earlier diagnosis without changed date of death Correct answer.
  2. Improved survival due to more effective treatment
  3. Selection of healthier volunteers into screening programs
  4. Detection of slow-growing tumors that would never cause symptoms

Explanation

Lead-time bias occurs because screening advances the time of diagnosis, so measured survival from diagnosis lengthens even if the time of death is unchanged. Overdiagnosis refers to detecting indolent tumors, and healthy-volunteer bias relates to self-selection.

Question 29Cancer Epidemiology, Prevention, and Screening

Which of the following is a recognized risk factor for esophageal squamous cell carcinoma?

  1. Barrett esophagus
  2. Tobacco and alcohol use Correct answer.
  3. Obesity
  4. Gastroesophageal reflux disease

Explanation

Tobacco smoking and heavy alcohol consumption are the dominant risk factors for esophageal squamous cell carcinoma. GERD, obesity, and Barrett esophagus are risk factors for esophageal adenocarcinoma, which arises in the distal esophagus.

Question 30Cancer Epidemiology, Prevention, and Screening

A new screening test is evaluated in a population with a disease prevalence of 1%. The test has 99% sensitivity and 95% specificity. What is the approximate positive predictive value?

  1. About 17% Correct answer.
  2. About 95%
  3. About 50%
  4. About 99%

Explanation

With 10,000 people, about 100 have disease and 99 are true positives; of 9,900 without disease, 495 are false positives (5%). Positive predictive value is 99 divided by (99 plus 495), roughly 17%. Low prevalence sharply reduces predictive value even for accurate tests.

Question 31Cancer Epidemiology, Prevention, and Screening

Which of the following is the strongest established risk factor for breast cancer in women?

  1. Breastfeeding for more than one year
  2. Early age at first pregnancy
  3. Early menarche and late menopause Correct answer.
  4. High parity

Explanation

Prolonged lifetime exposure to endogenous estrogen, reflected in early menarche and late menopause, increases breast cancer risk. High parity, prolonged breastfeeding, and early first pregnancy are associated with reduced risk.

Question 32Cancer Epidemiology, Prevention, and Screening

In evaluating a screening program, which study design most reliably avoids lead-time and length bias when assessing cancer mortality benefit?

  1. Ecological comparison of regional incidence
  2. Randomized controlled trial with cancer mortality as the endpoint Correct answer.
  3. Case series of screen-detected cancers
  4. Retrospective survival analysis of screened patients

Explanation

Randomization balances confounders and comparing cancer mortality between screened and unscreened arms avoids the survival biases inherent in comparing screened patients. Observational designs that measure survival from diagnosis are vulnerable to lead-time, length, and overdiagnosis bias.

Question 33Diagnostic Oncology, Staging, and Tumor Pathology

Which histologic feature best distinguishes malignant from benign follicular thyroid neoplasms?

  1. Capsular or vascular invasion Correct answer.
  2. Presence of colloid follicles
  3. Papillary architecture
  4. Nuclear clearing with pseudoinclusions

Explanation

In follicular thyroid tumors, the diagnosis of carcinoma rests on demonstrating transcapsular or vascular invasion, since cytologic atypia is unreliable. Nuclear clearing and pseudoinclusions define papillary carcinoma instead. Follicles and colloid occur in both benign and malignant lesions.

Question 34Diagnostic Oncology, Staging, and Tumor Pathology

A breast carcinoma shows strong diffuse membranous HER2 staining by immunohistochemistry. According to standard scoring, which score does this represent?

  1. 1+
  2. 0
  3. 2+
  4. 3+ Correct answer.

Explanation

HER2 immunohistochemistry is scored 0 to 3+, with strong complete membranous staining in more than 10% of tumor cells scoring 3+ and indicating positivity. Scores 0 and 1+ are negative, and 2+ is equivocal and requires in situ hybridization.

Question 35Diagnostic Oncology, Staging, and Tumor Pathology

In colorectal carcinoma, which molecular pathway is most strongly associated with the CpG island methylator phenotype and BRAF V600E mutation?

  1. NTRK fusion pathway
  2. Mismatch repair proficient adenoma-carcinoma sequence with APC mutation
  3. Chromosomal instability pathway
  4. Serrated pathway Correct answer.

Explanation

The serrated neoplasia pathway is characterized by CpG island methylation, BRAF V600E mutation, and often right-sided tumors. Chromosomal instability with APC mutation typifies the classic adenoma-carcinoma sequence. NTRK fusions are rare actionable events rather than a defined pathway here.

Question 36Diagnostic Oncology, Staging, and Tumor Pathology

Which tumor marker is most appropriate for monitoring disease in a patient with a germ cell tumor of the testis?

  1. CEA
  2. Alpha-fetoprotein and beta-hCG Correct answer.
  3. CA 19-9
  4. CA 125

Explanation

Testicular germ cell tumors are monitored with alpha-fetoprotein and beta-hCG, which also aid in classification and prognosis. CA 19-9 is used mainly in pancreatic and biliary tumors, CA 125 in ovarian cancer, and CEA in colorectal cancer.

Question 37Diagnostic Oncology, Staging, and Tumor Pathology

A lung adenocarcinoma is found to have an EGFR exon 19 deletion. Which statement best describes the clinical significance of this finding?

  1. It predicts response to EGFR tyrosine kinase inhibitors Correct answer.
  2. It indicates the tumor is a mesothelioma
  3. It is diagnostic of small cell carcinoma
  4. It predicts resistance to all targeted therapy

Explanation

Activating EGFR mutations such as exon 19 deletions are predictive biomarkers for sensitivity to EGFR tyrosine kinase inhibitors. They are found in a subset of lung adenocarcinomas and are not seen in small cell carcinoma or mesothelioma.

Question 38Diagnostic Oncology, Staging, and Tumor Pathology

Which staging system is used for most solid tumors to describe anatomic extent of disease?

  1. Child-Pugh classification
  2. Ann Arbor system
  3. TNM system Correct answer.
  4. FIGO system

Explanation

The TNM system describes tumor size and invasion (T), nodal involvement (N), and metastasis (M) and is applied to most solid tumors. Ann Arbor is used for lymphoma, FIGO for gynecologic cancers, and Child-Pugh assesses liver function.

Question 39Diagnostic Oncology, Staging, and Tumor Pathology

Which histologic subtype of non-small cell lung cancer is most strongly associated with peripheral location and glandular formation?

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

Explanation

Lung adenocarcinoma typically arises peripherally and shows glandular or mucinous differentiation. Squamous cell carcinoma tends to be central and shows keratinization or intercellular bridges. Small cell carcinoma is a neuroendocrine tumor with a different biology.

Question 40Diagnostic Oncology, Staging, and Tumor Pathology

A patient with a 2 cm breast tumor and 3 positive axillary nodes but no distant metastasis would be classified as which N category?

  1. N0
  2. N3
  3. N2
  4. N1 Correct answer.

Explanation

In breast cancer staging, N1 denotes metastasis to movable ipsilateral level I or II axillary lymph nodes. N0 indicates no nodal metastasis, N2 fixed or matted axillary nodes, and N3 more extensive nodal disease such as infraclavicular or internal mammary involvement.

Question 41Diagnostic Oncology, Staging, and Tumor Pathology

Which finding on a prostate needle biopsy is used to assign a Gleason grade group?

  1. Predominant and secondary architectural patterns Correct answer.
  2. Tumor volume on imaging
  3. Serum PSA level
  4. Presence of perineural invasion

Explanation

The Gleason grade group is derived from the predominant and secondary architectural patterns seen on histology. PSA and imaging inform risk stratification but do not define the Gleason score itself. Perineural invasion is a prognostic feature, not a grading criterion.

Question 42Diagnostic Oncology, Staging, and Tumor Pathology

Which chromosomal translocation is characteristic of follicular lymphoma?

  1. t(11;14)
  2. t(8;14)
  3. t(14;18) Correct answer.
  4. t(15;17)

Explanation

Follicular lymphoma is characterized by t(14;18), which places BCL2 under immunoglobulin heavy chain control and inhibits apoptosis. t(8;14) is seen in Burkitt lymphoma, t(11;14) in mantle cell lymphoma, and t(15;17) in acute promyelocytic leukemia.

Question 43Diagnostic Oncology, Staging, and Tumor Pathology

A biopsy of a pigmented skin lesion shows nests of atypical melanocytes at the dermoepidermal junction with pagetoid spread. Which diagnosis is most likely?

  1. Basal cell carcinoma
  2. Dermatofibroma
  3. Squamous cell carcinoma in situ
  4. Melanoma in situ Correct answer.

Explanation

Atypical melanocytic nests at the junction with pagetoid upward scatter are features of melanoma in situ. Squamous cell carcinoma in situ shows full-thickness epidermal atypia without melanocytic nests. Basal cell carcinoma forms basaloid islands with peripheral palisading, and dermatofibroma is a dermal spindle cell lesion.

Question 44Diagnostic Oncology, Staging, and Tumor Pathology

Which tumor suppressor gene is most commonly altered in high-grade serous ovarian carcinoma?

  1. RB1
  2. APC
  3. TP53 Correct answer.
  4. VHL

Explanation

High-grade serous ovarian carcinoma is characterized by near-universal TP53 mutations. APC mutations predominate in colorectal cancer, RB1 in retinoblastoma and small cell lung cancer, and VHL in clear cell renal cell carcinoma.

Question 45Diagnostic Oncology, Staging, and Tumor Pathology

Which of the following best defines a sentinel lymph node?

  1. The largest regional lymph node
  2. The node with the highest standardized uptake value on PET
  3. The node nearest the midline
  4. The first lymph node draining a primary tumor Correct answer.

Explanation

The sentinel node is the first node to receive lymphatic drainage from the primary tumor and is identified by dye or radiotracer mapping. Its status predicts regional nodal involvement. Size, location, and PET avidity do not define it.

Question 46Diagnostic Oncology, Staging, and Tumor Pathology

A gastric biopsy shows signet ring cells infiltrating the lamina propria with abundant desmoplasia. Which classification best fits this tumor?

  1. Diffuse-type gastric adenocarcinoma Correct answer.
  2. Intestinal-type gastric adenocarcinoma
  3. MALT lymphoma
  4. Gastrointestinal stromal tumor

Explanation

Diffuse-type gastric adenocarcinoma features signet ring cells and desmoplasia without gland formation, often associated with CDH1 loss. Intestinal-type tumors form glands and are linked to chronic inflammation and intestinal metaplasia. GIST is a mesenchymal tumor and MALT lymphoma is lymphoid.

Question 47Diagnostic Oncology, Staging, and Tumor Pathology

Which paraneoplastic marker is most closely associated with hepatocellular carcinoma?

  1. Alpha-fetoprotein Correct answer.
  2. CA 125
  3. Calcitonin
  4. Thyroglobulin

Explanation

Alpha-fetoprotein is elevated in a majority of hepatocellular carcinomas and is used with imaging in surveillance and diagnosis. CA 125 relates to ovarian cancer, calcitonin to medullary thyroid carcinoma, and thyroglobulin to differentiated thyroid cancer.

Question 48Diagnostic Oncology, Staging, and Tumor Pathology

Which feature on histology is most characteristic of Hodgkin lymphoma?

  1. Star-sky pattern of tingible body macrophages
  2. Reed-Sternberg cells in an appropriate inflammatory background Correct answer.
  3. Diffuse sheets of small cleaved lymphocytes
  4. Monoclonal plasma cell infiltrate

Explanation

Classic Hodgkin lymphoma is diagnosed by Reed-Sternberg cells, often CD15 and CD30 positive, within a mixed inflammatory background. A starry-sky pattern suggests Burkitt lymphoma, and diffuse small cleaved cells suggest follicular lymphoma. Plasma cell infiltrates suggest myeloma or plasmacytoma.

Question 49Diagnostic Oncology, Staging, and Tumor Pathology

A patient has a 3 cm renal mass with tumor thrombus extending into the renal vein but not beyond, and no nodal or distant spread. In renal cell carcinoma staging, which T category applies?

  1. T4
  2. T2
  3. T1
  4. T3 Correct answer.

Explanation

Renal vein involvement by tumor thrombus is classified as T3 in renal cell carcinoma staging. T1 and T2 are confined to the kidney by size, and T4 denotes invasion beyond Gerota's fascia.

Question 50Diagnostic Oncology, Staging, and Tumor Pathology

Which molecular alteration is characteristic of chronic myeloid leukemia?

  1. JAK2 V617F mutation
  2. BCR-ABL1 fusion Correct answer.
  3. PML-RARA fusion
  4. MYD88 L265P mutation

Explanation

Chronic myeloid leukemia is defined by the Philadelphia chromosome producing the BCR-ABL1 fusion, which is targeted by tyrosine kinase inhibitors. JAK2 V617F occurs in myeloproliferative neoplasms such as polycythemia vera, PML-RARA in acute promyelocytic leukemia, and MYD88 L265P in lymphoplasmacytic lymphoma.