Podcast
Questions and Answers
Which of the following is an example of an internal carcinogen that may lead to penile carcinoma?
Which of the following is an example of an internal carcinogen that may lead to penile carcinoma?
- Radiation exposure
- Asbestos inhalation
- Smegma in uncircumcised males (correct)
- Red and yellow food colors
A patient is diagnosed with hepatocellular carcinoma. Which of the following carcinogenic agents is most likely associated with this condition based on the provided information?
A patient is diagnosed with hepatocellular carcinoma. Which of the following carcinogenic agents is most likely associated with this condition based on the provided information?
- Red and yellow food colors (correct)
- Infection with Herpes Simplex virus type II
- Inhalation of asbestos fibers
- Exposure to UV radiation
Workers in a nuclear power plant are at increased risk of certain cancers due to their occupational exposure. Which of the following cancers is most strongly associated with exposure to artificial radiation?
Workers in a nuclear power plant are at increased risk of certain cancers due to their occupational exposure. Which of the following cancers is most strongly associated with exposure to artificial radiation?
- Basal cell carcinoma
- Squamous cell carcinoma
- Leukemia (correct)
- Malignant melanoma
A patient presents with a white patch on their tongue that affects the mucous membranes. Microscopically, it is diagnosed as keratinizing squamous metaplasia. This condition is best described as which of the following?
A patient presents with a white patch on their tongue that affects the mucous membranes. Microscopically, it is diagnosed as keratinizing squamous metaplasia. This condition is best described as which of the following?
A patient with a history of chronic atrophic gastritis is monitored for potential pre-neoplastic changes. Which of the following factors associated with chronic atrophic gastritis could contribute to the development of cancer?
A patient with a history of chronic atrophic gastritis is monitored for potential pre-neoplastic changes. Which of the following factors associated with chronic atrophic gastritis could contribute to the development of cancer?
A researcher is investigating the development of cancer and observes that tumor growth is significantly influenced by hormones. In this scenario, how are hormones primarily acting in the carcinogenic process?
A researcher is investigating the development of cancer and observes that tumor growth is significantly influenced by hormones. In this scenario, how are hormones primarily acting in the carcinogenic process?
A young patient is diagnosed with xeroderma pigmentosa. Which of the following mechanisms is directly impaired in this patient, increasing their risk of developing skin cancer?
A young patient is diagnosed with xeroderma pigmentosa. Which of the following mechanisms is directly impaired in this patient, increasing their risk of developing skin cancer?
During a study on carcinogenic agents, researchers identify a substance that requires metabolic convergence to become carcinogenic. Which type of carcinogenic agent is being described?
During a study on carcinogenic agents, researchers identify a substance that requires metabolic convergence to become carcinogenic. Which type of carcinogenic agent is being described?
A pathologist examines a tissue sample and identifies disordered, non-neoplastic cellular proliferation with loss of individual cell uniformity, but the basement membrane remains intact. Which of the following best describes this condition?
A pathologist examines a tissue sample and identifies disordered, non-neoplastic cellular proliferation with loss of individual cell uniformity, but the basement membrane remains intact. Which of the following best describes this condition?
A patient is diagnosed with a lung carcinoma and pleural mesothelioma. Which of the following substances is the most likely cause of these conditions?
A patient is diagnosed with a lung carcinoma and pleural mesothelioma. Which of the following substances is the most likely cause of these conditions?
Which of the following scenarios best exemplifies the role of hormones as promoters in carcinogenesis?
Which of the following scenarios best exemplifies the role of hormones as promoters in carcinogenesis?
A researcher is studying the effects of a novel environmental toxin on cellular DNA. After exposure to the toxin, cells exhibit increased DNA mutations but only progress to neoplasia in the presence of chronic inflammation. Which carcinogenic mechanism is most likely at play?
A researcher is studying the effects of a novel environmental toxin on cellular DNA. After exposure to the toxin, cells exhibit increased DNA mutations but only progress to neoplasia in the presence of chronic inflammation. Which carcinogenic mechanism is most likely at play?
A patient is diagnosed with a rare cancer linked to chronic exposure to a specific industrial chemical. Further investigation reveals that the chemical itself does not directly interact with DNA but causes epigenetic modifications leading to gene silencing. Which type of carcinogenic agent is most likely responsible?
A patient is diagnosed with a rare cancer linked to chronic exposure to a specific industrial chemical. Further investigation reveals that the chemical itself does not directly interact with DNA but causes epigenetic modifications leading to gene silencing. Which type of carcinogenic agent is most likely responsible?
A study reveals that individuals with a specific genetic polymorphism exhibit increased susceptibility to bladder cancer upon exposure to aromatic amines. This polymorphism results in reduced activity of enzymes responsible for detoxification of these compounds. Which of the following mechanisms is most likely responsible for the increased cancer risk?
A study reveals that individuals with a specific genetic polymorphism exhibit increased susceptibility to bladder cancer upon exposure to aromatic amines. This polymorphism results in reduced activity of enzymes responsible for detoxification of these compounds. Which of the following mechanisms is most likely responsible for the increased cancer risk?
A researcher is evaluating the carcinogenic potential of a newly discovered virus. They observe that the virus encodes a protein that binds to and inactivates the p53 tumor suppressor protein. Which mechanism of carcinogenesis is most likely involved?
A researcher is evaluating the carcinogenic potential of a newly discovered virus. They observe that the virus encodes a protein that binds to and inactivates the p53 tumor suppressor protein. Which mechanism of carcinogenesis is most likely involved?
A patient with ulcerative colitis undergoes frequent colonoscopies, and a biopsy reveals dysplasia in a flat lesion. The dysplasia is characterized by crypt architectural distortion, nuclear hyperchromasia, and increased mitotic activity extending to the surface epithelium. However, the basement membrane is intact. Which of the following best describes the appropriate management strategy?
A patient with ulcerative colitis undergoes frequent colonoscopies, and a biopsy reveals dysplasia in a flat lesion. The dysplasia is characterized by crypt architectural distortion, nuclear hyperchromasia, and increased mitotic activity extending to the surface epithelium. However, the basement membrane is intact. Which of the following best describes the appropriate management strategy?
A researcher is studying the effects of a novel compound on cellular transformation. They find that the compound induces DNA damage but only leads to tumor formation in cells lacking a functional DNA repair pathway. Which carcinogenic mechanism is most likely involved?
A researcher is studying the effects of a novel compound on cellular transformation. They find that the compound induces DNA damage but only leads to tumor formation in cells lacking a functional DNA repair pathway. Which carcinogenic mechanism is most likely involved?
Several patients who were treated with a specific chemotherapeutic agent later developed secondary malignancies. The agent is known to directly alkylate DNA. Which mechanism is most likely responsible for the development of these secondary cancers?
Several patients who were treated with a specific chemotherapeutic agent later developed secondary malignancies. The agent is known to directly alkylate DNA. Which mechanism is most likely responsible for the development of these secondary cancers?
A study on workers exposed to asbestos reveals an increased incidence of both lung carcinoma and mesothelioma. Which cellular mechanism is most likely responsible for asbestos-induced carcinogenesis?
A study on workers exposed to asbestos reveals an increased incidence of both lung carcinoma and mesothelioma. Which cellular mechanism is most likely responsible for asbestos-induced carcinogenesis?
A researcher investigates a population with high rates of hepatocellular carcinoma despite low rates of hepatitis B and C infections. Further investigation reveals widespread exposure to aflatoxin-contaminated food. Which mechanism best explains the increased cancer risk in this population?
A researcher investigates a population with high rates of hepatocellular carcinoma despite low rates of hepatitis B and C infections. Further investigation reveals widespread exposure to aflatoxin-contaminated food. Which mechanism best explains the increased cancer risk in this population?
Flashcards
Etiology of Cancer
Etiology of Cancer
Possible causes of cancer, mechanisms transforming normal cells.
Carcinogenic Agents
Carcinogenic Agents
Agents that can produce malignancy.
Smegma & Cancer
Smegma & Cancer
Uncircumcised males may produce penile carcinoma.
Bile Acids & Cholesterol
Bile Acids & Cholesterol
Signup and view all the flashcards
Hormone's Role in Cancer
Hormone's Role in Cancer
Signup and view all the flashcards
Non-Ionizing Radiation (UVR)
Non-Ionizing Radiation (UVR)
Signup and view all the flashcards
Alkylating Agents
Alkylating Agents
Signup and view all the flashcards
Tar (tobacco products)
Tar (tobacco products)
Signup and view all the flashcards
H. pylori
H. pylori
Signup and view all the flashcards
Pre-neoplastic Disorders
Pre-neoplastic Disorders
Signup and view all the flashcards
Familial adenomatous polyposis coli
Familial adenomatous polyposis coli
Signup and view all the flashcards
Xeroderma pigmentosa
Xeroderma pigmentosa
Signup and view all the flashcards
Chronic Irritation
Chronic Irritation
Signup and view all the flashcards
Hyperplasia
Hyperplasia
Signup and view all the flashcards
Metaplasia
Metaplasia
Signup and view all the flashcards
Liver Cirrhosis
Liver Cirrhosis
Signup and view all the flashcards
Some Benign Tumors
Some Benign Tumors
Signup and view all the flashcards
Dysplasia
Dysplasia
Signup and view all the flashcards
Carcinoma in situ
Carcinoma in situ
Signup and view all the flashcards
Azo Dyes
Azo Dyes
Signup and view all the flashcards
Study Notes
- Possible causes and mechanisms involved in the transformation of a normal cell into a neoplastic cell is the etiology of cancer.
- A single factor isn't responsible for the development of tumors.
- Carcinogenic factors in carcinogenesis have established roles, while others are still unknown.
Etiology of Neoplasia
- Carcinogenic agents (carcinogens)
- Preneoplastic (precancerous, premalignant) lesions
Carcinogenic Agents
- Agents that produce malignancy.
Classification of Carcinogens
- Internal carcinogens include smegma and hormones.
- External carcinogens include radiation, chemicals, hormonal therapy, and infectious agents.
Internal Carcinogens
- Smegma in uncircumcised males may produce penile carcinoma.
- Bile acids and cholesterol are carcinogenic to the colon.
- Hormones can affect tumor growth in hormone-dependent tumors and act as promoters (second step in carcinogenesis).
- Estrogen-dependent cancers can cause hyperestrogenemia: Breast, ovarian, endometrial carcinoma and clear cell carcinoma of the vagina.
- Androgen-dependent cancers can cause prostatic carcinoma.
External Carcinogens
- Non-ionizing radiation (UVR) is related to skin malignancies like squamous cell carcinoma, basal cell carcinoma, and malignant melanoma.
- Artificial ionizing radiation exposure
- atomic blast survivors
- secondary tumors from therapeutic irradiation
- Workers with radioactive isotopes
- may cause leukemia, thyroid carcinoma, osteosarcoma, and lung carcinoma.
Chemical Carcinogens
- Direct acting agents:
- Alkylating agents (chemotherapy) as cyclophosphamide can cause leukemia.
- Indirect acting agents that need metabolic convergence:
- Benzpyrenes can cause scrotum skin malignancy.
- Tar (tobacco products) can cause carcinoma of the lung, urinary bladder, oral cavity, larynx, and esophagus.
- Azo dyes (red and yellow food colors) can cause hepatocellular carcinoma.
- Aflatoxin (product of Aspergillus flavus fungus contaminating grains and peanuts) can cause hepatocellular carcinoma.
- Nitrites converted to nitrosamine by bacterial flora in the stomach with achlorhydria can cause stomach carcinoma.
- Asbestos can cause lung carcinoma and pleural mesothelioma.
- Arsenic, chromium, and nickel can cause lung carcinoma.
Hormonal Therapy
- Estrogen therapy can cause hyperestrogenemia.
- Oral pills and anabolic drugs can cause liver cell adenoma.
Infections
- Bacterial carcinogens:
- Helicobacter pylori may cause carcinoma and B cell lymphoma of the stomach.
- Parasitic carcinogens:
- Bilharziasis can cause urinary bladder carcinoma.
- Viral carcinogens:
- Human papilloma virus (HPV) types 1, 2, 4, and 7 can cause squamous cell papilloma.
- HPV types 6 & 11 can cause genital warts.
- HPV types 16 & 18 can cause cancer of the cervix.
- Herpes Simplex type II can cause cancer of the cervix.
- Hepatitis B virus can cause hepatocellular carcinoma.
- Epstein-Barr virus (EBV) can cause Burkitt's lymphoma or nasopharyngeal carcinoma.
Pre-Neoplastic Disorders
- Non-malignant lesions that may become malignant.
Classification of Pre-Neoplastic Disorders
- Autosomal dominant inherited cancer syndromes:
- Familial adenomatous polyposis coli: Numerous polyps (at least 100) occur in the colon in late childhood (10–14 years) and inevitably lead to adenocarcinoma in early middle age (30-45 years) with the responsible gene of APC
- Familial retinoblastomas: Development of retinoblastoma of the eye in early childhood with the responsible gene of RB.
- Autosomal recessive syndromes of defective DNA repair:
- Xeroderma pigmentosa causes failure of DNA repair of UV induced DNA mutation, leading to prematurely aged multiple skin cancers.
- Familial cancers include breast, ovarian, and colonic carcinomas.
- Acquired preneoplastic disorders:
- Chronic irritation by dental ulcer, varicose ulcer, sinuses draining osteomyelitis, burn scar, or chronic inflammation as chronic atrophic gastritis.
- Hyperplasia: atypical endometrial hyperplasia and atypical mammary hyperplasia.
- Metaplasias: squamous, leukoplakia, or glandular metaplasia. Leukoplakia appears as a white patch affecting mucous membranes of sites like the tongue, vulva, larynx, and bladder and microscopically, it is keratinizing squamous metaplasia.
- Liver cirrhosis can develop into hepatocellular carcinoma.
- Hamartomas
- Some benign tumors as well as adenomatous polyps in the colon.
- Dysplasia as dysplastic bronchial mucosa in smokers.
- Carcinoma in situ
- Prognosis:
- Precancerous lesions display a variable malignant potential and are classified.
High-risk Lesions
- Lesions in which the development of cancer is invariable (100%):
- Multiple familial polyposis coli
- Xeroderma pigmentosa
Low-Risk Lesions
- Lesions in which the incidence of malignancy is low (3-5%)
- Leukoplakia
- Endometrial hyperplasia
- Dysplasia
Dysplasia
- Disordered non-neoplastic cellular proliferation characterized by the loss of individual cell uniformity and the loss of normal arrangement within the tissue and often accompanies metaplasia or hyperplasia.
- Examples include the uterine cervix, larynx, urinary bladder, and colon
- Dysplastic changes affect the whole thickness of the epithelium, but the basement membrane is intact and there is no invasion called carcinoma in situ (intra-epithelial carcinoma).
- Mild to moderate dysplasia may be reversible or may persist or regress when the irritating cause stops.
- Progress leads to carcinoma in situ where the whole thickness of dysplasia but basement membrane is intact and no invasion of underlying connective tissue occurs, which may finally become invasive carcinoma.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
