paroneoplastic syndromes, mechanisms, and risks for cancer

Question 1

What are paraneoplastic syndromes?

Answer 1

Rare disorders triggered by cancer, where symptoms are caused by biological substances or immune responses rather than by direct pressure from the tumor itself.

Question 2

What are common features of paraneoplastic syndromes?

Answer 2

They can be the first sign of cancer, are often irreversible, and can be life-threatening.

Question 3

What paraneoplastic syndrome is associated with renal cancers?

Answer 3

Renal cancers can stimulate excess erythropoietin production, leading to polycythemia.

Question 4

What is the paraneoplastic effect of lung cancers?

Answer 4

Lung cancers may produce substances that stimulate clotting factors, causing Deep Vein Thrombosis (DVTs) or Pulmonary Embolisms (PEs).

Question 5

What paraneoplastic syndrome is linked to intracranial cancers?

Answer 5

Intracranial cancers can stimulate production of antidiuretic hormone (ADH), leading to Syndrome of Inappropriate Antidiuretic Hormone (SIADH).

Question 6

What causes the symptoms in paraneoplastic syndromes?

Answer 6

Symptoms are caused by biological substances or immune responses triggered by the tumor, rather than the tumor’s physical presence or pressure on nearby tissues.

Question 7

How does pain manifest in cancer patients?

Answer 7

Can arise early but may be absent in early stages for some cancers; influenced by fear, anxiety, sleep loss, fatigue, and physical deterioration.

Question 8

What are the direct mechanisms of cancer-related pain?

Answer 8

Pressure on nerves, invasion of sensitive structures, obstruction of blood flow, stretching of visceral surfaces, and tissue destruction.

Question 9

What are the indirect mechanisms of cancer-related pain?

Answer 9

Inflammatory response, infection, and referred pain.

Question 10

Why might certain affected tissues be more painful in cancer?

Answer 10

Painful sites include bones (tumor pressure, fractures), mucosa (ulcers from tumors/treatment), abdomen (bowel inflammation or obstruction), liver (stretching against abdominal wall).

Question 11

What is the most frequently reported symptom of cancer and its treatment?

Answer 11

Fatigue.

Question 12

What factors may contribute to cancer-related fatigue?

Answer 12

Theorized causes include sleep disturbances, biochemical changes, psychosocial/environmental factors, and physical factors.

Question 13

What is cachexia, and what are its manifestations in cancer patients?

Answer 13

Cachexia includes fat loss, muscle wasting, and inflammation, with early satiety, altered taste, and unmet metabolic needs due to increased energy expenditure.

Question 14

How does cachexia affect bodily functions?

Answer 14

Alters heart function, liver protein synthesis, hypothalamic hormone secretion, and GI function, impairing protein production and muscle regeneration.

Question 15

What is anemia in cancer, and what are its symptoms?

Answer 15

Low RBC count; symptoms include fatigue, pallor, dizziness, and dyspnea on exertion, leading to risk of ischemia and organ dysfunction.

Question 16

What are the mechanisms of anemia in cancer?

Answer 16

Causes include bone marrow malignancy, chronic bleeding, malnutrition, chemotherapy, and poor iron absorption.

Question 17

What is thrombocytopenia, and what are its symptoms in cancer patients?

Answer 17

Low platelet count; symptoms include bruising, petechiae, spontaneous bleeding, and prolonged clotting time.

Question 18

How does leukopenia impact cancer patients?

Answer 18

Increases infection risk; leukopenia is a low WBC count caused by tumor invasion in the bone marrow, chemotherapy, radiation, or medication effects.

Question 19

What is the leading cause of complications and death in cancer patients?

Answer 19

Infection, due to immunosuppression from cancer, chemotherapy, surgery, invasive devices, wounds, or exposure to sick visitors.

Question 20

How is the GI system affected by cancer or its treatment?

Answer 20

Impacts include nausea, vomiting, and diarrhea due to effects on the GI microbiome, chemotherapy/radiation, surgery, invasive devices, and infections.

Question 21

What hair/skin changes can occur with cancer treatment?

Answer 21

Hair loss (alopecia) from chemotherapy, skin breakdown, dryness, and radiation burns, as well as rashes, petechiae, and purpura from thrombocytopenia.

Question 22

What are petechiae, and how are they linked to cancer?

Answer 22

Small, flat red or purple spots from bleeding under the skin, often linked to low platelet counts (thrombocytopenia).

Question 23

What is purpura, and how does it manifest in cancer patients?

Answer 23

Red or purple patches on the skin or mucous membranes due to bleeding under the skin, often associated with low platelet levels in cancer patients.

Question 24

What viruses are associated with specific cancers?

Answer 24

HPV -> cervical cancer; EBV -> Burkitt’s lymphoma, Hodgkin’s lymphoma; Herpes virus -> cervical cancer, Burkitt’s lymphoma; HBV/HCV -> hepatocellular carcinoma.

Question 25

What are tumor markers, and how are they used?

Answer 25

Biochemical substances produced by cells, used for screening (e.g., PSA), diagnosis (e.g., ER-2 for breast, CA-125 for ovarian), and monitoring clinical course.

Question 26

What genetic and epigenetic factors influence cancer risk?

Answer 26

Decreased detoxifying enzymes, changes to DNA repair genes, activation of immune systems, and a favorable cell environment for growth.

Question 27

What are common carcinogenic agents for oral cancers?

Answer 27

Alcohol, tobacco, HPV.

Question 28

What are common carcinogenic agents for liver cancers?

Answer 28

Aflatoxins, alcohol, estrogen-progesterone contraceptives, HBV, HCV, tobacco.

Question 29

How does tobacco use contribute to cancer risk?

Answer 29

Contains >7000 chemicals, at least 70 known carcinogens; linked to multiple cancers, including lung, bladder, and myeloid leukemia; leads to significant mortality.

Question 30

What is the relationship between nutrition and cancer risk?

Answer 30

Diet influences cell processes like proliferation, signaling, and DNA repair; high consumption of red/processed meats linked to higher colorectal cancer incidence.

Question 31

How does alcohol consumption increase cancer risk?

Answer 31

Carcinogenic effects from acetaldehyde and reactive oxygen species; alters cell cycle, and leads to nutritional deficiencies impacting mucosal integrity.

Question 32

What impact does obesity have on cancer risk?

Answer 32

Associated with 13 types of cancer; metabolic changes in adipose tissue promote chronic inflammation and tumor-promoting signaling pathways.

Question 33

What role does physical inactivity play in cancer risk?

Answer 33

Increases risk due to obesity; regular activity may reduce risks of certain cancers like breast and colon.

Question 34

How does ionizing radiation contribute to cancer?

Answer 34

Causes DNA damage and apoptosis; associated with acute leukemias, multiple myelomas, and several solid tumors through mechanisms like oncogene activation and chromosomal damage.

Question 35

What cancers are associated with UV radiation exposure?

Answer 35

Melanoma, basal cell carcinoma, squamous cell carcinoma; mechanisms involve gene mutations and inflammation.

Question 36

What are potential effects of radiofrequency electromagnetic radiation on cancer risk?

Answer 36

Considered a possible carcinogen; conflicting studies on associations with leukemia and brain cancer; mechanisms not fully understood.

Question 37

How do infections influence cancer risk?

Answer 37

Induce chronic inflammation, leading to dysplasia and decreased immunity; major infections linked to gastric (H. pylori), cervical (HPV), and liver (HBV/HCV) cancers.

Question 38

What is the relationship between air pollution and lung cancer?

Answer 38

Lung cancer risk linked to inhalation of particulate matter, causing pulmonary inflammation, oxidative stress, and tissue remodeling.

Question 39

How do chemical and occupational hazards contribute to cancer?

Answer 39

Exposure to carcinogenic chemicals leads to epigenetic alterations and DNA mutations; specific occupations linked to cancers like bladder cancer (dyes) and lung cancer (drivers).