Neoplasia and Cancer Overview

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Questions and Answers

Which type of carcinoma is known for early blood spread?

Renal cell carcinoma (correct)

Lung carcinoma

Basal cell carcinoma

Squamous cell carcinoma

Which carcinoma is associated with early hematogenous spread in addition to renal cell carcinoma?

Mucinous adenocarcinoma

Hepatocellular carcinoma (correct)

Melanoma

Neuroendocrine carcinoma

Which of the following caricinomas is not typically associated with early blood spread?

Follicular carcinoma of the thyroid

Follicular carcinoma of the skin (correct)

Hepatocellular carcinoma

Choriocarcinoma of the uterus

What type of mutations can induce cancer by decreasing gene function?

Recessive mutations Signup and view all the answers

Choriocarcinoma of the uterus is known for what type of spread?

Early blood spread Signup and view all the answers

Proto-oncogenes are normally associated with which biological function?

Cell growth Signup and view all the answers

How do oncogenes differ from their normal counterparts?

They are mutated and promote uncontrolled growth Signup and view all the answers

Which carcinoma is associated with early blood spread and can affect the thyroid?

Follicular carcinoma of the thyroid Signup and view all the answers

Which statement is true regarding the relationship between recessive mutations and cancer?

Recessive mutations can lead to decreased gene function and possibly induce cancer Signup and view all the answers

What is the primary role of proto-oncogenes in cellular processes?

To regulate cell growth Signup and view all the answers

What percentage of all cancers is attributed to inherited cancer caused by germline mutations?

5-20% Signup and view all the answers

Where do germline mutations occur?

In sperm or ova cells Signup and view all the answers

What is the primary distinction of cancers caused by germline mutations?

They are referred to as inherited cancer. Signup and view all the answers

Which of the following statements is true regarding germline mutations?

They are passed directly from parent to child. Signup and view all the answers

How does the frequency of germline mutations compare to other types of mutations?

They are less common than somatic mutations. Signup and view all the answers

What is the primary characteristic of a teratoma?

It is composed of mature tissue from at least two embryonic layers. Signup and view all the answers

Which embryonic layers can contribute to the formation of a teratoma?

Endoderm, ectoderm, and mesoderm. Signup and view all the answers

Which of the following statements about teratomas is false?

They are usually aggressive and fast-growing tumors. Signup and view all the answers

Where are teratomas most commonly found?

In the ovaries or testis. Signup and view all the answers

What tissue types can be represented in a teratoma?

Mature tissues like hair, teeth, and organs. Signup and view all the answers

What is the primary origin of Basal Cell Carcinoma?

Basal cell layer of the skin Signup and view all the answers

What characterizes the malignant changes in epithelial cells before the basement membrane is infiltrated?

Microscopic changes without stromal invasion Signup and view all the answers

In which of the following sites are malignant epithelial changes commonly found?

Cervix, breast, and bronchi Signup and view all the answers

What is a common gross appearance of Basal Cell Carcinoma?

Small nodule that increases in size Signup and view all the answers

Which statement accurately describes Basal Cell Carcinoma?

It is locally malignant. Signup and view all the answers

Which statement is true regarding the formation of masses in cases of malignant changes in epithelial cells?

They generally do not form a mass. Signup and view all the answers

What is indicated by malignancy in epithelial cells without stromal invasion?

Non-invasive precursors of cancer Signup and view all the answers

What is a characteristic consequence of Basal Cell Carcinoma if not treated?

It may ulcerate. Signup and view all the answers

Which of the following best describes the typical visibility of malignant changes in the epithelial cells?

They are often undetectable without microscopy. Signup and view all the answers

Which of the following is NOT a feature of Basal Cell Carcinoma?

Highly aggressive with rapid metastasis Signup and view all the answers

Study Notes

Neoplasia (Tumors)

Tumors are new growths of tissue, often forming a mass. Malignant neoplasms are cancers.
"Tumor" means swelling in Greek. "Neoplasia" means "new formation."

Cancer

Cancer is uncontrolled division of genetically abnormal cells, spreading to surrounding tissues and distant sites.

Cancer Pathogenesis

Cancer arises from interaction between environmental factors and a genetic predisposition.
Normal cells divide as needed, stop growing, and adhere to other cells. They undergo apoptosis (programmed cell death) when no longer needed.
Cancer cells lack these controls: they divide uncontrollably, detach, and invade surrounding tissues.

Cancer Cell Characteristics

Less specialized than normal cells
Ignore apoptotic signals (programmed cell death)
Can alter surrounding tissue (microenvironment)
Can evade the immune system to grow

Cancer Causes - DNA Damage

Environmental factors: Tobacco, radiation, UV rays, viruses.
Endogenous factors: Reactive oxygen species (ROS) during metabolism.
Random errors during DNA replication.
Protective mechanisms: Stop cell division, activate DNA repair, induce apoptosis. Unrepaired damage leads to mutations.

Gene Mutations

Gene mutations are permanent DNA changes causing abnormal or non-functional proteins.
Acquired mutations: Most common type, gene damage during a person's lifetime, leading to sporadic cancer.
Germline mutations: Less common, inherited from parents, increasing risk of inherited cancer.

Genes Linked to Cancer

Tumor suppressor genes: These genes control cell division and repair DNA damage. Mutations reduce their function, leading to unchecked cell growth.
Oncogenes: These genes normally promote cell growth. Mutations increase their activity, causing accelerated cell division and contributing to cancer.

Various agents (e.g., arsenic, benzene) are linked specific types of cancer (e.g., skin, lung, liver cancers).
Various viruses (e.g., HPV, HBV) have been linked specific types of cancer.
Environmental factors (e.g., radiation, tobacco) significantly elevate many cancer risks.

Tumor Classification

Behavior: Benign (slow growth, confined), In Situ (pre-cancerous), Malignant (rapid spread), Unknown Behavior
Origin: Epithelial (lining organs/glands), Connective (bone, cartilage, fat)

Microscopic Criteria of Malignant Cells

Undifferentiated: Lacking characteristics of their original tissue type
Pleomorphic: Varying in size and shape
Hyperchromatic Nuclei: Darker nuclei due to increased DNA
High N/C Ratio: Higher nuclear-to-cytoplasmic ratio
Prominent Nucleoli: Larger nucleoli within cells
Lack of Polarity: Disorganized cell structure
Frequent Abnormal Mitoses: Irregular cell division

Benign vs. Malignant Tumors

Key difference is whether tumor cells invade surrounding tissues (malignant) or remain in a confined space (benign). Malignant cancers spread (metastasize).
Benign tumors are often encapsulated and are much less likely to be life-threatening

Carcinoma vs. Sarcoma

These are classifications of malignant tumors based on tissue of origin. Carcinomas arise from epithelial cells, sarcomas from connective tissue. Differentiated by cell types, structure, and spread characteristics.

Tumor Spread Mechanisms

Local invasion: direct spread to surrounding tissues.
Blood spread: cancer cells enter bloodstream are carried to distant sites
Lymphatic spread: cancer cells travel via lymph channels to regional lymph nodes and then beyond

Other Tumor Spread Details

Transcoelomic implantation
Important role of angiogenesis (blood vessel formation) for tumor growth

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Description

This quiz covers key concepts related to neoplasia and cancer, including tumor characteristics, cancer pathogenesis, and the factors contributing to cancer development. Understand the differences between normal and cancerous cells, and explore the environmental and genetic influences on cancer growth.