Neoplasia I,II

What is cancer?

Uncontrolled cell proliferation and growth that can invade other tissues

What is a tumour?

Swelling, can be benign or malignant - Could even be inflammatory or a foreign body

What is a neoplasia?

Neoplasia is a new growth which is not in response to a stimulus - Can be benign, premalignant or malignant - Can occur in any cell in any organ.

What does the neoplasm consist of structurally?

Neoplasms are comprised of proliferating cells that make up the parenchyma and supportive stroma made of connective tissue and blood vessels. Signup and view all the answers

What do you mean by a malignant neoplasm?

A neoplasm with potentially lethal, abnormal characteristics which has the ability to invade and metastasise. Signup and view all the answers

What is a benign neoplasm?

A neoplasm which does not have the ability to metastasise and invade other cells is benign. Signup and view all the answers

Are benign tumours always harmless?

Some benign tumours can be locally harmful and destructive. They are not always harmless. Signup and view all the answers

What are the factors of the severity of a neoplasm?

<ol> <li>Differentiation</li> <li>Rate of growth</li> <li>Local invasion</li> <li>Metastasis</li> </ol> Signup and view all the answers

What is differentiation? How does it affect a neoplasm's diagnosis?

The extent to which neoplastic tissues resemble their corresponding normal tissue of origin would affect the diagnosis of neoplasm. Being well differentiated and closely resembling the normal tissue of origin would mean it is less aggressive. The more anaplastic or undifferentiated it becomes, it becomes tougher to identify by morphology alone. It means it is more aggressive and severe. Signup and view all the answers

What are some features of poor differentiation?

<ol> <li>Nuclear pleomorphism- variability in nuclear size/ shape</li> <li>Abnormal nuclear features- high nuclear: cytoplasmic ratio, clumped chromatin, prominent nucleoli</li> <li>increased mitotic activity</li> <li>Loss of cellular polarity/ order</li> <li>Tumour giant cells</li> <li>Necrosis</li> </ol> Signup and view all the answers

What are the morphological differences between benign and malignant tumours?

Benign tumours are well differentiated and closely resemblance tissue origin. Malignant tumours have anaplastic features and generally poorer differentiation. Signup and view all the answers

What is metastatic potential?

Metastatic potential is the ability to metastasise or spread to other sites within the tissues. Signup and view all the answers

How can we detect malignancy in epithelial cells?

In the epithelium, malignancy goes beyond the basement membrane - invasion - Access to blood vessels, lymph nodes etc. Signup and view all the answers

What is dysplasia?

Neoplastic changes in the epithelium with the cytomorphological features of malignancy but confined within the basement membrane. It is seen as a precursor to malignancy because it hasn't yet reached the stroma, the point at which it would be considered malignant. There's architectural disruption and nuclear pleomorphism. Signup and view all the answers

Does dysplasia mean certain malignancy?

Dysplasia is seen as a precursor to the stage of malignancy but it doesn't always lead to it and it can regress. Signup and view all the answers

What is carcinoma in situ?

Carcinoma in situ is defined as dysplasia of the entire epithelial layer without invasion of the basement membrane into the underlying tissue. Signup and view all the answers

What are the properties of benign tumours?

<ol> <li>Cohesive and expansile masses</li> <li>Localised</li> <li>Don’t metastasise</li> <li>Usually slow growth</li> <li>May be encapsulated</li> <li>Rim of compressed connective tissue= fibrous capsule</li> </ol> Signup and view all the answers

What are properties of malignant tumours?

<ol> <li>Invasive</li> <li>Penetrate organ walls / tissues / epithelial surfaces</li> <li>Next to metastases, invasiveness is the most reliable feature that differentiates malignant from benign tumours</li> </ol> Signup and view all the answers

What is metastasis?

The spread of tumour to a site discontinuous from the source organ / tissue Signup and view all the answers

What is metaplasia?

Reversible change from one mature cell type to another mature cell type Signup and view all the answers

How can tumours be classified?

Tumours can be classified by benign/ malignant and in terms of the cell of origin. Signup and view all the answers

How can epithelial tumours be classified?

Epithelial tumours can be classified in terms of the ectoderm, mesoderm and endoderm, and types of epithelial cells like squamous, cuboidal, columnar, glandular etc. Signup and view all the answers

What is the nomenclature of benign tumour of glandular/ secretory epithelium?

Adenoma (glands may or may not be present in the tumour) Signup and view all the answers

What is the nomenclature of benign tumour of non-glandular/surface epithelium?

Papilloma (finger like warty projections) Signup and view all the answers

What would you call a benign tumour on the glandular epithelium of the thyroid?

Thyroid adenoma Signup and view all the answers

What would you call a benign tumour on the stratified squamous epithelium?

Squamous cell papilloma Signup and view all the answers

What is the nomenclature of benign mesenchymal tumour?

Tissue or cell of origin and suffix 'oma' Signup and view all the answers

What is the nomenclature of smooth muscle mesenchymal tumour?

Leiomyoma Signup and view all the answers

What is the nomenclature of skeletal muscle mesenchymal tumour?

Rhabdomyoma Signup and view all the answers

What is the nomenclature of adipose mesenchymal tumour?

Lipoma Signup and view all the answers

What is the nomenclature of blood vessel mesenchymal tumour?

Haemangioma Signup and view all the answers

What is the nomenclature of bone mesenchymal tumour?

Osteoma Signup and view all the answers

What is the nomenclature of cartilage mesenchymal tumour?

Chondroma Signup and view all the answers

What is the nomenclature of fibrous mesenchymal tumour?

Fibroma Signup and view all the answers

What is a malignant epithelial tumour called?

Carcinoma Signup and view all the answers

What is the nomenclature for malignant tumours derived from glandular/ ductular epithelium?

Adenocarcinoma Signup and view all the answers

What is the nomenclature for malignant epithelial tumours derived from surface non-glandular epithelia?

Carcinoma with prefix of cell of origin Signup and view all the answers

What would you call a malignant tumour in the squamous epithelium?

Squamous cell epithelium Signup and view all the answers

What would you call a malignant tumour in the glandular epithelium of colon?

Colonic adenocarcinoma Signup and view all the answers

What is the nomenclature for malignant mesenchymal tumours?

Sarcoma with a prefix of cell of origin Signup and view all the answers

What would you call a malignant tumour in the smooth muscle?

Leiomyosarcoma Signup and view all the answers

What would you call a malignant tumour in the skeletal muscle?

Rhabdomyosarcoma Signup and view all the answers

What would you call a malignant tumour in the adipose tissue?

Liposarcoma Signup and view all the answers

What would you call a malignant tumour in the blood vessel?

Angiosarcoma Signup and view all the answers

What would you call a malignant tumour in the bone?

Osteosarcoma Signup and view all the answers

What would you call a malignant tumour in the cartilage?

Chondrosarcoma Signup and view all the answers

What would you call a malignant tumour in the fibrous tissue?

Fibrosarcoma Signup and view all the answers

What are teratomas?

Teratomas originate from the gonads and contain cells representing all three germ cell layers- ectoderm, mesoderm and endoderm. Benign teratomas involve the formation of teeth, hair, muscle, neural tissue and cartilage. Malignant teratoma tissues are more primitive. Signup and view all the answers

What are precursor cell tumours?

Precursor cell tumours bear histological resemblance to embryological in which it arises- Retinoblastoma, Nephroblastoma and Hepatoblastoma. It often occurs in young patients. It has a suffix of 'blastoma' because it is derivative of the embryological tissue. Signup and view all the answers

What are mixed tumours?

A mixed tumour is a neoplasia in both the epithelial and mesenchymal tissue. A single clone may branch off into both types of tissues. Signup and view all the answers

What is the nomenclature for malignant mixed tumours?

Carcinosarcoma; from epithelial and mesenchymal word roots Signup and view all the answers

What are some types of brain tumours?

<ol> <li>Glioblastoma multiforme</li> <li>Astrocytoma</li> <li>Meningioma</li> <li>Neurinoma</li> <li>Ependymoma</li> <li>Oligoendroglioma</li> <li>Medulloblastoma</li> </ol> Signup and view all the answers

What is a hamartoma?

Hamartoma is a non neoplastic disordered overgrowth of normal tissue which has developmental abnormalities. Signup and view all the answers

Where does a hamartoma occur?

Hamartoma is indigenous to the site of occurrence and is made of the same tissue that it is home to. e.g. a birthmark on the skin. Signup and view all the answers

What is a choristoma?

Choristoma is a rare benign tumour consisting of microscopically normal tissue derived from germ cell layers foreign to that body site. Signup and view all the answers

Where does a choristoma occur?

Choristoma occurs in an abnormal location thus it is not indigenous to the site of occurrence. Example- Normal non neoplastic pancreatic nodule in the duodenum/ stomach. Signup and view all the answers

What are some types of Haematolymphoid malignancy?

<ol> <li>Lymphoma</li> <li>Myeloma</li> <li>Leukaemia</li> </ol> Signup and view all the answers

What is a lymphoma?

It is a malignancy of B or T cell origin, often beginning in lymph nodes, but can also be extra nodal. There are different types of lymphomas like Hodgkins/ Non Hodgkins and B/T cell lymphoma. Signup and view all the answers

What is a myeloma?

Malignancy of plasma cells Signup and view all the answers

What is leukaemia?

Malignancy of white blood cells which begins in the bone marrow. Signup and view all the answers

What are some melanocytes neoplasms? (skin related cancer)

<ol> <li>Melanoma</li> <li>Melanocytic naevus</li> </ol> Signup and view all the answers

What is a melanoma?

It is a malignancy of melanocytes- which are the cells that produce pigment in the skin. Signup and view all the answers

What is melanocytes naevus?

Benign proliferation of melanocytes Signup and view all the answers

What are some special nomenclatures for tumours?

<ol> <li>Based on histological appearance (papillary carcinoma of the thyroid- finger like projections)</li> <li>Genetic alterations- rhabdomyosarcoma with TFCP2 arrangement</li> <li>Mixed elements with more than one type of malignant cell- ameloblastic fibrosarcoma, teratocarcinosarcoma.</li> <li>Eponymous tumour- derived from the researcher's name like Warthin tumour, Kaposi sarcoma. The eponymous names have become more synonymous than the technical names so it is used.</li> </ol> Signup and view all the answers