Dr. Irungu Sent SEM 2

Question 1

The chemical carcinogen aflatoxin B1 derived from a fungus which contaminates grain foods most commonly induces

Accepted Answer

Hepatocellular carcinoma — Aflatoxin B1 from Aspergillus growing on poorly stored grains causes liver cancer. ---

Question 2

Which pair does NOT correctly match tumour with causative agent?

Accepted Answer

Hepatocellular carcinoma — Hepatitis A virus — Hepatocellular carcinoma is caused by HBV and HCV, not Hepatitis A virus. Hep A never causes chronic infection or cancer. ---

Question 3

Direct-acting carcinogenic agents

Accepted Answer

Include medications used in anticancer regimens e.g alkylating agents — Direct-acting carcinogens do not require metabolic conversion. Alkylating agents directly damage DNA. ---

Question 4

Which is FALSE regarding chemical carcinogens?

Accepted Answer

Promoters such as phorbol esters are directly carcinogenic — Promoters are not carcinogenic alone; they promote the growth of already initiated cells. Initiators are directly carcinogenic. ---

Question 5

Natural ultraviolet radiation

Accepted Answer

Damages DNA by forming pyrimidine dimers — UV radiation damages DNA by forming pyrimidine dimers, leading to mutations and skin cancer. ---

Question 6

The following occupational cancers are correctly matched EXCEPT

Accepted Answer

Radon — Bone cancer — Radon is associated with lung cancer, not bone cancer. ---

Question 7

Which is NOT true of H. pylori infection?

Accepted Answer

Sequence: chronic inflammation→atrophy→intestinal metaplasia→dysplasia→cancer — Only a small minority of infected persons develop cancer. Most get gastritis or peptic ulcers. ---

Question 8

Which statement is NOT true of HBV and HCV?

Accepted Answer

HBV carries multiple genomes encoding viral oncoproteins — HBV has a single small genome and does not carry multiple genomes encoding viral oncoproteins. ---

Question 9

Screening of cancers

Accepted Answer

Is application of simple tests across healthy population before symptoms develop — Screening involves applying simple tests to a healthy population before symptoms develop to detect cancer early. ---

Question 10

Early detection of cancers

Accepted Answer

Is a concept of timely diagnosis including early diagnosis and screening — Early detection encompasses timely diagnosis, including early diagnosis in symptomatic patients and screening in asymptomatic individuals. ---

Question 11

Which is NOT true regarding global cancer statistics?

Accepted Answer

About 10 million deaths in 2020 attributed to cancer — The incidence of cancer is increasing globally, not in sharp decline. ---

Question 12

In Kenya

Accepted Answer

Risk of developing cancer before age 75 is 14.3% among men and 18% among women — In Kenya, cancer is not the leading cause of death; infectious diseases still lead. The stated risks are correct. ---

Question 13

One of the following is NOT true regarding precursor lesions

Accepted Answer

Squamous dysplasia of bronchial mucosa in smokers is a risk factor for lung cancer — Removal of precursor lesions DOES prevent cancer development. That is the purpose of screening and early intervention. ---

Question 14

Villous adenomas of the colon

Accepted Answer

Are associated with high risk of transformation to colorectal carcinoma — Villous adenomas have the highest malignant potential among colorectal polyps, with a significant risk of transformation. ---

Question 15

The following are responsible for alveolar damage in ARDS EXCEPT

Accepted Answer

Platelet-activating factor (PAF) — IL-10 is an anti-inflammatory cytokine that suppresses inflammation, while the others actively damage alveoli in ARDS. ---

Question 16

Which is NOT a diffuse obstructive pulmonary disease?

Accepted Answer

Relaxation atelectasis — Atelectasis is lung collapse, not an obstructive disease characterized by difficulty exhaling. ---

Question 17

Which is NOT a typical finding in COPD?

Accepted Answer

Increased FEV1 to FVC ratio — In COPD, the FEV1 to FVC ratio is DECREASED below 0.70, indicating airflow obstruction. ---

Question 18

Nasopharyngeal carcinoma

Accepted Answer

Tends to be radiosensitive — Nasopharyngeal carcinoma has a strong link to EBV and is notably radiosensitive, making radiotherapy a primary treatment. ---

Question 19

Which tumour suppressor gene abnormality is most common in BOTH SCLC and NSCLC?

Accepted Answer

3p deletions — 3p deletions occur in virtually all lung cancers, regardless of histological type, and involve multiple tumour suppressor genes. ---

Question 20

Fluid cytopathology specimens include the following EXCEPT

Accepted Answer

Cystic masses — Lump aspirate is obtained by Fine Needle Aspiration (FNA), which is aspiration cytology, not fluid cytopathology. ---

Question 21

Which are the most frequent sites of venous thrombosis?

Accepted Answer

Veins of lower extremity — Deep vein thrombosis (DVT) most commonly occurs in the deep veins of the lower extremities. ---

Question 22

In a state of shock there is

Accepted Answer

Cardiovascular collapse — Shock is defined as the failure of the cardiovascular system to maintain adequate tissue perfusion, leading to cardiovascular collapse. ---

Question 23

Which disorder most likely associated with EXUDATE rather than transudate?

Accepted Answer

Suppurative inflammation — Suppurative inflammation, characterized by pus formation, results in exudate, which is protein-rich and inflammatory. ---

Question 24

Heart failure cells in lungs are actually

Accepted Answer

Macrophages — Heart failure cells are macrophages that have phagocytosed red blood cells that have leaked into the alveoli due to increased pulmonary venous pressure in left heart failure. ---

Question 25

Hallmark of ACUTE inflammation

Accepted Answer

Increased vascular permeability of microcirculation — The key hallmark of acute inflammation is increased vascular permeability, allowing plasma proteins and leukocytes to enter tissues. ---

Question 26

Hallmark of CHRONIC inflammation

Accepted Answer

Mononuclear cell infiltration — Chronic inflammation is characterized by infiltration of mononuclear cells like lymphocytes, plasma cells, and macrophages. ---

Question 27

Granulomatous inflammation is characterized by all the following EXCEPT

Accepted Answer

Fibroblasts and neovascularization — Central caseous necrosis is typical of tuberculosis and some fungal infections, but not all granulomatous inflammation features it. ---

Question 28

The hallmark of acute inflammation

Accepted Answer

Vascular stasis — Increased vascular permeability is the defining hallmark of acute inflammation, leading to the cardinal signs. ---

Question 29

Which of the following is the hallmark of acute inflammation?

Accepted Answer

Neutrophils — Neutrophils are the characteristic cellular hallmark of acute inflammation, acting as the first responders. ---

Question 30

Which is a reversible change?

Accepted Answer

Swelling of endoplasmic reticulum — Swelling of organelles, such as the endoplasmic reticulum, is an early reversible change in cell injury. ---

Question 31

Which mediates systemic effects of inflammation, chemotaxis and stimulates adhesion molecules?

Accepted Answer

Interleukin 1 (IL-1) and tumor necrosis factor — IL-1 and TNF are key mediators of systemic inflammatory effects, including fever and induction of adhesion molecules. ---

Question 32

Which of the following is a 38 year old man's wound — 4cm circumscribed mass with peripheral brightness on x-ray that gradually resolves — best described as?

Accepted Answer

Metaplasia — The description of a mass with peripheral brightness on X-ray that resolves and is attributed to heterotopic bone formation after trauma is consistent with myositis ossificans, a form of metaplasia. ---

Question 33

Growth factor elaborated by macrophages recruiting macrophages and fibroblasts and inducing ALL steps of angiogenesis

Accepted Answer

Fibroblast growth factor — Vascular Endothelial Growth Factor (VEGF) is the primary mediator of angiogenesis, inducing all its steps. ---

Question 34

A 20-year-old with lacerated wound stitched. One week later prominent raised irregular nodular scar develops. Best describes

Accepted Answer

Keloid formation — A prominent, raised, irregular nodular scar extending beyond wound margins is characteristic of a keloid. ---

Question 35

Which of the following is NOT a malignant tumour?

Accepted Answer

Leiomyoma — Leiomyoma is a benign smooth muscle tumor. Its malignant counterpart is leiomyosarcoma. ---

Question 36

Burkitt lymphoma in Kenya — which lymphoproliferative disorder is common in children?

Accepted Answer

Burkitt Lymphoma — Burkitt Lymphoma is the most common childhood cancer in equatorial Africa, strongly associated with EBV and endemic in the malaria belt. ---

Question 37

Which tumour marker for ovarian cancer?

Accepted Answer

CA 125 — CA 125 is the primary tumor marker used for ovarian cancer detection and monitoring. ---

Question 38

True of testicular tumours EXCEPT

Accepted Answer

Seminomas are insensitive to radiotherapy — Seminomas are highly sensitive to radiotherapy, making it an effective treatment modality. ---

Question 39

Which is a characteristic feature of pituitary adenomas?

Accepted Answer

Cellular monomorphism and lack of reticulin network — Pituitary adenomas are typically characterized by uniform, monomorphic cells and a loss of the normal reticulin network. ---

Question 40

H. pylori organisms predominantly demonstrated

Accepted Answer

Within superficial mucus overlying epithelial cells — H. pylori colonizes the superficial mucus layer overlying gastric epithelial cells. ---

Question 41

Defects in celiac disease include

Accepted Answer

Lymphatic transport — Celiac disease affects all stages of nutrient absorption, including intraluminal digestion, terminal digestion, and transport via blood and lymphatics. ---

Question 42

Features of Vibrio cholerae infection include

Accepted Answer

Release of chloride ions into lumen after opening of CFTR — Cholera toxin causes excessive chloride ion release into the lumen via CFTR, leading to massive fluid loss. ---

Question 43

NOT a feature of Crohn's disease

Accepted Answer

Toxic megacolon — Toxic megacolon is a characteristic complication of Ulcerative Colitis, not typically Crohn's disease. ---

Question 44

Features of C. difficile infection EXCEPT

Accepted Answer

Hyperplasia of surface epithelium — C. difficile infection leads to damage and sloughing of the epithelium, not hyperplasia. ---

Question 45

43-year-old with burning substernal pain. Biopsies show columnar epithelium with goblet cells above GEJ. This represents

Accepted Answer

Metaplasia — The presence of columnar epithelium with goblet cells above the gastroesophageal junction is known as Barrett's esophagus, a form of intestinal metaplasia. ---

Question 46

Cervical Intraepithelial Neoplasia

Accepted Answer

Always manifested by cytological atypia and dysplasia — By definition, CIN represents cytological atypia and dysplasia, which are the cellular changes seen in this precancerous condition. ---

Question 47

Aetiological theories for endometriosis EXCEPT

Accepted Answer

Neoplastic theory — The neoplastic theory is not a recognized etiological theory for endometriosis. Theories include regurgitation, metaplasia, and dissemination. ---

Question 48

True of serous endometrial cancer

Accepted Answer

TP53 mutations in nearly all cases — TP53 mutations are found in nearly all cases of serous endometrial cancer, which is an aggressive, non-estrogen-dependent subtype. ---

Question 49

Leiomyomata

Accepted Answer

Are often asymptomatic and multiple — Leiomyomas (fibroids) are often asymptomatic, multiple, and found in women of reproductive age. They are estrogen-dependent and shrink after menopause. ---

Question 50

Most frequent tumours of the ovary

Accepted Answer

Immature teratomas — Surface epithelial-stromal cell tumors are the most common type of ovarian neoplasms, accounting for 65-70% of cases. ---

Dr. Irungu Sent SEM 2

Questions, Answers & Explanations