lymphomas, brain tumours, embryonal tumours and teratomas Flashcards
definition of lymphomas
lymphomas are neoplastic proliferations of lymphoid cells of various types.
definition of leukaemia
leukaemias are neoplastic proliferations of the cells (mainly blood white cells and their precursors) of the haemopoietic bone marrow
classification and nomenclature of lymphomas
2 main groups:
-Hodgkin’s disease.
and the rest which are grouped under the name
-non -hodgkins lymphoma. the most common and important of these are the lymphocytic lymphomas
lymphomas: clinical features and behaviour
Most present clinically with LYMPHADENOPATHY -
lymph node enlargement, localised or generalised
Some may also infiltrate liver (HEPATOMEGALY),
spleen (SPLENOMEGALY) or bone marrow
(marrow replacement, with haematological consequences)
Bad prognosis types may diffusely infiltrate other
organs
Hodgkin’s disease- main types
-Nodular Lymphocyte-predominant Hodgkin’s (6%) [GOOD]
Classical Hodgkin’s lymphoma:
-Lymphocyte rich Hodgkin’s (5%) [GOOD]
-Mixed cellularity Hodgkin’s (15-30%) [IN BETWEEN]
-Nodular sclerosing Hodgkin’s (60-80%) [GOOD]
-Lymphocyte-depleted Hodgkin’s (<1%) [POOR]
the different types of Hodgkin’s disease are based on the differing proportions of reed-sternberg cells and lymphocytes
the cells in classical Hodgkin’s disease
the neoplastic cell in classical Hodgkin’s disease are called the Reed-Sternberg cell. other cells present are mainly lymphocytes, with some eosinophils and fibroblasts
different types of classical Hodgkin’s disease
Lymphocyte rich Hodgkin’s
FEW R-S cells and lots of lymphocytes
Lymphocyte depleted Hodgkin’s
LOTS of R-S cells and few lymphocytes
Mixed cellularity Hodgkin’s
roughly equal proportions of R-S cells and lymphocytes
Nodular sclerosing Hodgkin’s
as mixed cellularity, but different architecture (see later)
lymphocytic lymphoma- simplified classification
B CELL LYMPHOMA - low grade (good)
B CELL LYMPHOMA - high grade (bad)
T CELL LYMPHOMA - low grade (good)
T CELL LYMPHOMA - high grade (bad)
myeloma
MYELOMA is a tumour of mature plasma cells. It presents with bone tumours, osteolytic, painful, but with interesting systemic effects (anemia, renal/cardiac failure, infections, hypercalcemia).
most common primary tumours of the brain
THE MOST COMMON PRIMARY TUMOURS OF THE BRAIN ARE DERIVED FROM THE SUPPORT CELLS, CALLED ‘ GLIAL CELLS’
GLIAL CELLS ARE:- Astrocytes Oligodendrocytes Ependymal cells ALL CAN GIVE RISE TO TUMOURS, BUT ASTROCYTOMAS ARE THE MOST COMMON
astrocytomas
ALL ASTROCYTOMAS BEHAVE IN A MALIGNANT MANNER, BY LOCAL INVASION, BUT DO NOT METASTASIZE.
PROGNOSIS depends on GRADE
ASTROCYTOMA GRADES 1 - 4
1 = GOOD
4 = BAD
embryonal tumours
EMBRYONAL TUMOURS are derived from embryonic remnants of primitive “blast’ tissue
KEY FACTS
Mainly in young children
Highly malignant
Spread early and widely by lymphatics and veins
Sensitive to chemotherapy
Formerly rapidly fatal, chemotherapy has revolutionised prognosis
embryonal tumours
Nephroblastoma (Wilms’ tumour) - in kidney, most common.
Neuroblastoma – mostly in adrenal gland, derived from primitive adrenal medullary precursors (neuroblasts); next commonest.
MUCH RARER ARE
Retinoblastoma - retina; often bilateral; genetic basis.
Medulloblastoma - cerebellum
Hepatoblastoma - liver
teratomas
TERATOMAS are tumours derived from primordial germ cells which retain the capacity to differentiate along all 3 primitive embryological lines. Hence teratomas should contain representatives of ectoderm, mesoderm and endoderm.
Since they are of germ cell origin, they mainly occur in the OVARY and TESTIS
teratoma of the ovary- key facts
TERATOMA OF THE OVARY - KEY FACTS
Young women
BENIGN
Invariably cystic (‘benign cystic teratoma)
Cyst contains keratin (“dermoid cyst of ovary”)
Skin, hair, bronchial &gut epithelium, thyroid, neuroglia, bone, cartilage
GOOD PROGNOSIS
