Download PM NEOPLASIA

NEOPLASIA
DR.ROOPA
Pathophysiology
Premed 2
Neoplasia
Neoplasm is an abnormal mass of tissue
as a result of neoplasia.
 Uncontrollable or abnormal proliferation of
cells.

Types
 A neoplasm can be benign, potentially
malignant (pre-cancer), or malignant
(cancer).
 Benign neoplasms include uterine fibroids
and melanocytic nevi (skin moles). They
do not transform into cancer.


Potentially malignant neoplasms include
carcinoma in situ. They do not invade and
destroy but, given enough time, will
transform into a cancer.

Malignant neoplasms are commonly called
cancer. They invade and destroy the
surrounding tissue, may form metastases
and eventually kill the host.
Metastasis sometimes abbreviated mets,
is the spread of a disease from one organ
or part to another non-adjacent organ or
part.
 cancer cells can break away, leak, or spill
from a primary tumor, enter lymphatic and
blood vessels, circulate through the
bloodstream, and be deposited within
normal tissue elsewhere in the body.

Malignant
(+) invasion: spread
to nearby structures
 (+)metastasis: spread
to distant structures
 (+)anaplasia :
cells are very different
from the normal cells
(poorly differentiated)

vs




Benign
(-) invasion
(+) capsule
(-)metastasis
Resemble the tissue
of origin (well
differentiated)
Anaplasia







Pleomorphism
Hyperchromatism (dark nuclei)
Increased nuclear-cytoplasm ratio
Abnormal mitosis
Prominent nucleoli
The more anaplastic, the more aggressive the
cancer
The more anaplastic, the more responsive to
chemo and radiotherapy
Forms of Malignant tumors

Carcinoma: malignant tumor of epithelial origin
1. squamous cell carcinoma
cancer of the skin
cancer of the esophagus
2. adenocarcinoma: glands
cancer of the breast
cancer of the pancreas
3. transitional cell carcinoma
cancer of the bladder
Forms of Malignant tumors


Sarcoma: of mesenchymal origin
osteosarcoma
rhabdosarcoma
leiomyosarcoma
liposarcoma
Teratoma: from all 3 germ layers
skin, bone, cartilage, teeth, intestinal
ovaries and testis: most common
may also be benign
Osteosarcoma
Liposarcoma
Teratoma
Forms of Benign tumors
Papilloma: Adenoma: glandular epithelium
-ovary, breast
 Mesenchymal origin
-leiomyoma, lipoma, fibroma, chondroma

Papilloma
epithelium of skin, larynx and tongue; fingerlike
projections
Properties of Neoplasms



Monoclonality
the neoplasm comes from a single
precursor cell
Invasion
enters the blood vessels and
lymphatics
Metastases
blood vessels: sarcomas
lymphatic: carcinoma
Properties of Neoplasms

Common sites of metastases
liver, lung, brain,
adrenal glands, lymph nodes
bone marrow.
Clinical signs of malignancy



Cachexia
wasting, weakness, weight loss, anemia, infection
cause: CACHECTIN
Endocrine abnormalities
prolactinoma
ovarian tumors
Paraneoplastic syndromes
ectopic production of hormones
lung cancer : ACTH
Carcinogenesis and carcinogens
Chemical agents
 Physical agents
 Viruses
 Activation of cancer-promoting genes
 Inhibition of cancer-suppressing genes

Carcinogenesis and carcinogens
Cigarette smoking : lung CA, laryngeal CA
 Excessive sun: Skin CA
 Asbestos: Mesothelioma
 Nitrosamines: Gastric CA
 Alcohol: Esophageal CA
 Low-fiber diet: Colon CA

Carcinogenesis and carcinogens
High-fat diet: Breast CA
 Aniline dyes: bladder Ca
 Aflatoxin: liver CA
 PVC: Angiosarcoma of the liver
 DES: Clear cell adenocarcinoma of the
vagina
 Nickle, chromium, uranium: lung CA

Carcinogenesis and carcinogens
HTLV – 1: Adult T cell leukemia
 HPV: cervical CA
 EBV: Nasopharyngeal CA, Burkitts
lymphoma
 HBV: Hepatocellular CA
 HHV-8: Kaposi sarcoma
 Helicobacter pylori: Gastric CA

An oncogene is a gene that, when
mutated or expressed at high levels, helps
turn a normal cell into a tumor cell.
 Oncogenes
bcl-2: inhibits apoptosis
Follicular lymphoma
c-myc : Burkitts lymphoma

Cancer suppresor genes
(anti oncogene)





A tumor suppressor gene, or anti-oncogene, is a gene
that protects a cell from one step on the path to cancer.
When this gene is mutated to cause a loss or reduction
in its function, the cell can progress to cancer, usually in
combination with other genetic changes.
p53: “ guardian of the genome”
mutated in 50% of all malignant tumors
causes cell cycle arrest in G1, time for DNA repair
unsuccessful repair: apoptosis

LI-FRAUMENI SYNDROME
familial cancers of the breast, soft
tissue sarcomas, brain tumors,
leukemias.
Cancer suppresor genes
(anti oncogene)
WT-1 and WT-2: Wilms tumor
 BRCA -1: breast and ovarian CA
 BRCA – 2: breast CA


The stage of a cancer is a descriptor
(usually numbers I to IV) of how much the
cancer has spread.
Grading: degree of differentiation of the
cells
 Staging: spread of the tumor
-uses the TNM system

TNM staging system
 Cancer staging can be divided into a
clinical stage and a pathologic stage. In
the TNM (Tumor, Node, Metastasis)


system, clinical stage and pathologic stage
are denoted by a small "c" or "p" before
the stage.

CANCER TREATMENT

CHEMOTHERAPY
CYTOTOXIC DRUGS+BODY DEFENSES
SINGLE AGENT
COMBINATION CHEMOTHERAPY
_AVOIDS SINGLE AGENT RESISTANCE
CAN USE LOWER DOSE
BETTER REMISSION AND CURE RATE
RADIATION
TARGETS DNA
KILL TUMOR WITHOUT DAMAGE TO SURROUNDING
TISSUES
TUMOR MUST BE ACCESSIBLE











SURGERY

METHOD OF CHOICE,CAN REMOVE ENTIRE
TUMOR,DEBULKING
ADJUVANT CHEMOTHERAPY OR RADIATION
IMMUNOTHERAPY
.ELIMINATES CANCER CELLS ONLY
.PROVIDES PROTECTION AGAINST RECURRENCE
.T_CELL BASED OR ANTIBODY RESPONSES
.CONJUGATED ANTIBODIES
.NONSPECIFIC ENHANCEMENT OF THE IMMUNE
SYSTEM






