Neoplasia Flashcards
Neoplasia
Process of uncontrolled growth. Accumulation of cells d/t proliferation and/or evasion of apoptosis
Neoplasm / Tumor
Abnormal mass of tissue. Growth exceeds and is uncoordinated w/ normal tissue. Persists in same excessive manner after cessation of stimuli which evoked the change.
What are the features of neoplasms?
Progressive, purposeless, pathological proliferation of cells. Loss of cell division control. DNA damage at growth control genes “checkpoints” is central. Carcinogens → DNA damage → Neoplasm
Too much proliferation, not enough apoptosis.
Benign Tumor
Neoplasm that grows w/o invading adjacent tissue / spreading to distant sites (metastasis). Usually well-circumscribed (w/ a lack of invasion). Generally amenable to local surgery. Well differentiated
Malignant Tumors
Neoplasm that invades surrounding tissue. Usually spreads to distant sites (metastasis). Well or poorly differentiated.
Intermediate Tumor
Locally invasive tumor. Not benign but w/ no tendency for metastasis. (Locally malignant)
Carcinoma in Situ
Dysplasia. Pre-invasive cell proliferation. Cytological features of malignancy. Cell morphology looks abnormal.
A neoplasm is composed of parenchyma and stroma. What are the components / function of the parenchyma?
Comprised of clonal neoplastic cells, this determines its biologic behavior. Tumor derives its name based on the parenchymal component. (neoplastic cells / tumor cells) Morphology: large nuclei, disordered arrangement
A neoplasm is composed of parenchyma and stroma. What are the components / function of the stroma?
Comprised of CT, blood vessels, macrophages, lymphocytes (tumor infiltrating lymphocytes - TILs). These cells determine the growth and evolution of the tumor. Scant stroma = soft/fleshy tumor.
Desmoplasia / Scirrhous
Hyperplasia of activated fibroblasts. Collagen deposition, stains blue color w. trichrome stain.
Abundant collagenous stroma in a tumor/neoplasm. This makes the tumor feel stony hard = (Scirrhous)
Prostate / Breast cancers
Adenoma
Epithelial Tissue, Benign, Glandular
Papilloma
Epithelial Tissue, Benign, Non-glandular
Benign epithelial tumors from surface lining, based on gross appearance. Tumor of squamous, transitional, ductal epithelium. Finger-like / warty projections from epithelial surfaces - branching pattern.
Carcinoma
Epithelial Tissue, Malignant
-oma suffix
Mesenchymal Tissue, Benign
Exceptions: granuloma, hematoma, hamartoma, choristoma
-sarcoma suffix
Mesenchymal Tissue, Malignant
Cystadenomas
Adenomas w/ cavities or cysts
Polyp
Club-shaped growth. Benign epithelial tumor/hyperplasia. Projects from mucosal surface into lumen of a hollow viscus. Rarely malignant. Polyp describes the shape/appearance.
Choristoma
Tumor-like condition. Normal tissue located in the wrong place. The rest of one tissue is ectopic (in a foreign place).
Hamartoma
Tumor-like condition. Non-neoplastic tumor-like lesion w/ DISORGANIZED and HAPHAZARD growth of tissues normally found at a given site. Right tissue in the right place, just disorganized. Example: pulmonary hamartoma = “jumbled” cartilage, bronchial epithelia, CT
Coin Lesion: firm/descrete, often calcified, <2cm
General features of carcinomas / sarcomas (malignant neoplasms)
Capsule generally absent, rapid growth, invasion present, atypical mitosis present
General features of benign tumors
Capsule generally present, slow growth, invasion absent, no atypical mitosis seen
Lymphoma
Cancer derived from lymph nodes or lymphoid tissue. Most are non Hodgkin’s lymphoma. Stomach is most common extranodal site for a primary malignant lymphoma.
Leukemia
Cancer derived from bone marrow stem cells. CLL (chronic lymphocytic leukemia) is most common in adults (and in general). ALL is the most common childhood leukemia and cancer.
Teratoma
Tumor composed of more than one parenchymal cell type. But Monoclonal - begins w/ only one cell. Derived from more than one germ layer. Tissue of origin: totipotent cells (gonads). Mature teratoma = dermoid cyst. Immature = teratocarcinoma
Peutz-Jeghers Syndrome
Type of Hamartoma Hereditary Intestinal Polyposis Syndrome Autosomal dominant genetic disease Benign hamartomatous polyps in GI tract + hyperpigmented macules (lips & oral mucosa) [black patches in lips/mouth]
Monoclonality
Origin of tumors from a single precursor cell
All neoplasms are monoclonal: both benign and malignant tumors derive from single precursor cell. New subclones arise from the descendants of original cell by multiple mutations.
Non-neoplastic proliferations are polyclonal
Criteria to differentiate benign vs malignant neoplasm
Differences based on appearance and behavior
Criteria:
1. Rate of growth
2. Differentiation and anaplasia (no differentiation)
3. Local Invasion
4. Metastasis
% of cells that are in S phase of cell cycle. Distinguish b/t normal tissue, malignant neoplasm, benign neoplasm
Normal Tissue: 1%
Benign Neoplasm: 1 - 10%
Malignant Neoplasm: 20 - 80%
Neoplasm Increased Growth Rate: Doubling Time
30 doublings = 1g
10 more doublings = 1kg
Neoplasm Increased Growth Rate: Fraction of tumor cells in proliferative pool
% of cells in S phase
Submicroscopic phase: higher growth fraction.
Later stages: low growth fraction <20%
Neoplasm Increased Growth Rate: Cell production vs cell loss
High growth fraction = grow rapidly
Low growth fraction = grow slowly
PCNA & Ki-67
PCNA = proliferating cell nuclear antigen score
Ki-67
Both used as markers for cellular proliferation (mitotic activity)
If low = decreased proliferation
If high = cell will proliferate
- Well-differentiated tumor
- Moderately differentiated tumor
- Poorly differentiated tumor
- Anaplastic / Undifferentiated tumor
- Benign
- Benign/malignant
- Malignant/benign - poor resemblance to normal tissue
- Complete lack of differentiation (structural & functional)Anaplasia is hallmark of high grade malignant tumor
No resemblance to normal tissue, high met potential
May only be ID’d by expression of cell markers / cytological findings.
Three factors that help you recognize CELLULAR ATYPIA
Seen only in pre-malignant and malignant tumors. Recognized by: 1. cellular pleomorphism 2. nuclear changes: nuclear/nucleolar pleomorphism, dense/irregular outline, hyperchromicity
3. (1:1 N/C ratio) (normal = 1:5)
Pleomorphism
Variation in size & shape of cells & nuclei
Hyperchromasia
Abundant DNA Extremely dark staining
Nucleus-to-cytoplasm ratio
Normally 1:5
Increased ratio 1:1 or 1:2
Cytologic features of anaplasia or poorly differentiated tumors
Nuclear & cellular pleomorphism, hyperchromatic nucleus, ↑N/C ratio, prominent nucleoli, abundant & atypical mitoses, bizarre tumor giant cells, loss of tissue architecture/function, more agressive
What are tumor giant cells and what is their significance?
Tumor giant cells represent anaplasia. Single huge polymorphic nucleus or > 2 nuclei. Hyper-chromatic and large nuclei.
What is the significance of recognizing anaplasia?
Presence of anaplasia implies a poorly differentiated neoplasia. More aggressive tumor w/ poorer prognosis.
Abnormal mitotic figures
Cell is proliferating. Key is that they are not the normal shape! Does not mimic any normal figures in prophase, metaphase, telophase. Mitoses alone don’t define malignancy, but the more abnormal the mitoses, the more likely the neoplasm is malignant.
Two important factors in tumor angiogenesis
VEGF & FGF
Pro-Angiogenic Factors (Angiogenic Factors)
VEGF
bFGF
HIF
Anti-angiogenic factors
Thrombospondin-1
Angiostatin
Endostatin
Tumstatin
How big can a tumor get w/o angiogenesis?
2mm is max size: limited by the ability of nutrients to diffuse into it. Produces tumor angiogenic factors that stimulate proliferation of blood vessels. Central ischemic necrosis when tumor outgrows its blood supply.
E-cadherin
Attaches cells together. In many malignant tumors, E-cadherin is not produced. Reduces cohesiveness of tumor cells.
Laminin / Laminin Receptor
Allow cellular attachment to matrix component.
Collagenases / MMPs
Tumor cells or fibroblasts/inflammatory cells release collagenases (MMPs) to degrade type IV BM collagen. Tumor cells can induce stroma cells to produce these enzymes that degrade the ECM.
Fibronectin
Binding of fibronectin to its receptor helps tumor cell migration. Tumor cell secreted motility factor plays a critical role in migration (locomotion). Tumor cells secrete molecules to promote invasion.
CD44
Expression of CD44 on tumor cells seems to favor metastasis
What are the three routes of metastasis?
Seeding of body cavities
Lymphatic Spread - most common in carcinoma > adenoma
Hematogenous Spread - most common in sarcomas
No lymphatic spread in which three carcinomas?
Follicular carcinoma: local invasion
Renal cell carcinoma: renal vein
Hepatocellular carcinoma: hematogenous spread
Hematogenous Spread
Typical of sarcomas, and carcinomas in late stage. Arteries are more difficult for tumor to penetrate. Cells follow venous flow to other organs. Liver and lungs frequently involved. Can cause tumor emboli.
Metastases characteristics
Multiple mass lesions w/ central areas of umbilication (ischemia and infarction).
Sentinel Lymph Node
1st node in a regional lymphatic system that receives lymph flow from primary tumor. Detected by radio labeled tracers or blue dyes. Used for detecting spread of melanomas, breast cancers, colon cancers, others
Most common site and symptom for bone metastasis
Vertebral column: batson paravertebral venous plexus connects vena cava and vertebral bodies. Pain is most common Sx of bone mets. Best relieved by local radiation therapy. 2 types: osteoblastic and osteolytic metastasis.
Factors Indicating Osteoblastic Metastasis
Radio-dense loci on x-ray. ↑serum alk phosphatase: indicates reactive bone formation. Example: prostate cancer is the most common type that has mets to bone. Example: prostate cancer.
Factors indicating Osteolytic Metastasis
Lucencies (dark spots) in bone on x-ray. Path. fractures. Tumors produce factors that activate osteoclasts:
PG E2, Osteoclast activating factor, IL-1
Potential for hypercalcemia. Example: multiple myeloma
Most common met site for stomach adenocarcinoma
Virchow’s left supraclavicular node
Most common met site for breast cancer
Lung, bone
Most common met site for colorectal cancer
Liver
Most common met site for renal adenocarcinoma
Lung
Most common met site for lung cancer
Adrenal / Liver
Most common met site for melanoma
Liver / Lung
Most common met site for prostate
Bone
Most common met site for testicular cancer
Para-aortic nodes
What is BrdU used for?
BrdU is a thymidine analong. Thymidine is a nucleotide used in DNA synthesis. Uptake in S phase. High nucleotide uptake implies that a large number of tumor cells are in the S phase, which will proceed to mitoses and undergo proliferation. High uptake suggests high grade tumor and poor prognosis.
What is mitotic index used for?
Used to grade tumors. Higher mitotic index = higher grade of tumor = poorer prognosis.
Four Grades of Neoplasia
I: Well differentiated
II: Moderately differentiated
III: Poorly differentiated
IV: Nearly anaplastic
TNM Staging system of neoplasia
T = size of primary tumor
T0 = In situ T1-4 = 4 is largest (increasing size)
N = nodal involvement
N0 = no nodes N1-3: extent of nodal involvement
M= distant mets
M0 = No mets M1-2: extent of mets
Dukes staging system
Used for colorectal cancers
Ann Arbor staging system
Used for Hodgkin and non Hodgkin lymphomas
Top cancer deaths in males
Lung & bronchus 30%
Prostate 9%
Colon & rectum 9%
Top cancer deaths in females
Lung & bronchus 26%
Breast 15%
Colon & rectum 9%
Top cancer incidence in males
Prostate 25%
Lung & bronchus 15%
Colorectal cancers 10%
Top cancer incidence in females
Breast 27%
Lung & bronchus 14%
Colorectal cancers 10%
The death rate from _________ cancer is higher in Japan as compared to the US
Stomach Cancer