Ch 13: WBC, Lymph Node, Spleen, & Thymus Pt 1. Flashcards
what are the two essential properties of hematopoietic stem cells
pluripotency
self-renewing
what are the two primary lymphoid organs
thymus
bone marrow
what are the five types of secondary lymphoid organs
lymph nodes
spleen
tonsils and adenoids
peyers patches
appendix
what is the most widely distributed and easily accessible lymphoid tissue
lymph nodes
spleen weight (16-20 yrs)
150-200g (170g)
spleen weight (20-65 yrs)
155 g
spleen weight (over 80 yrs)
100 g
what are the two broad categories of white cell disorders
proliferative disorders
leukopenias
what is leukopenia
deficiency of leukocytes
what is neutropenia
deficiency of neutrophils
what is a major consequence of leukopenia
agranulocytosis which makes you most susceptible to bacterial and funcal infections
what is the most common cause of agranulocytosis
drug toxicity
what are some consequences of agranulocytosis
ulcerating necrotizing lesions of the gingiva, floor of mouth, buccal mucosa, and pharynx
can cause severe, invasive bacterial or fungal infections in the lungs, urogenitital tract, or kidneys
a neutropenic patient is at high risk for what
deep fungal infections caused by candida and Aspergillus
what is lymphadenitis
activation of resident immune cells which leads to morphologic changes in lymph nodes
primary follicles enlarge and develop germinal centers
what are germinal centers
found in lymph nodes
highly dynamic structures in which B cells acquire the capacity to make high-affinity antibodies against specific antigens
unfiltered lymph flows into a lymph node through which vessel
afferent vessel
filtered lymph fluid flows out of a lymph node through which vessel
efferent vessel
what is follicular hyperplasia
presence of large germinal centers (secondary follicles) which are surrounded by naive B cells (mantle zone)
caused by stimuli that activate humoral immune responses
what is acute myeloid leukemia (AML)
immature progenitor cells accumulate in the bone marrow
what is myelodysplastic syndrome (MDS)
ineffective hematopoiesis and resultant peripheral blood cytopenias
what are myeloproliferative neoplasms
increased production of one or more terminally differentiated myeloid elements like granulocytes
what most commonly causes white cell neoplasms
translocations, specifically Philadelphia chromsome
what are three types of lymphotropic viruses
human T-cell leukemia virus-1 (HTLV-1)
EBV
human herpesvirus-8 (HHV-8)
what type of lymphoma accounts for 2/3rds of all T-cell lymphomas and is closely linked to celiac disease
enteropathy-associated T-cell lymphoma (EATL)
what is associated with and known to cause gastric B-cell lymphomas
H. pylori
what is associated with and known to cause anaplastic large cell lymphoma
breast implants
what are leukemias
neoplasms that present with widespread involvement of the bone marrow and peripheral blood
what are lymphomas
proliferations of white cells, usually lymphocytes, that usually present as discrete tissue masses like in the tonsils
what are the five types of lymphoid neoplasms
precursor B-cell
peripheral B-cell
precursor T cell
peripheral T and NK cell
hodgkin lymphoma
what is a type of T-cell associated marker that is also expressed by lymphocytic leukemia and mantle cell lymphoma
CD5 antibody
what does the receptor of a B cell look like
has two antigen binding sites
what does the receptor of a T cell look like
has just one antigen binding site
85-90% of lymphoid neoplasms are of which cell origin
B-cell
what are some features of acute lymphoblastic leukemia/lymphomas (ALL)
-how does it typically show up
neoplasms composed of immature B or T cells (lymphoblasts)
most common cancer of children
aggresive and shows up as bone marrow failure or as a mass
75% cure rate with aggresive chemotherapy
what is the most common cancer of children
acute lymphoblastic leukemia/lymphoma
what are the three major symptoms of ALL
anemia
neutropenia (fever)
thrombocytopenia (bleeding)
what is a nuclear protein widely used as a marker for pre-B and pre-T lymphoblast leukemias
terminal deoxynucleotidyl transferase antibody (TdT)
how is flow cytometry used
helps identify cells in solution
used to evaluate peripheral blood, bone marrow, and other body fluids
identify and quantify immune cells and characterize hematological malignancies
what are some features of chronic lymphocytic leukemia (CLL)
most common leukemia of adults in Western World
median survival is 4-6 years
what symptoms are present in chronic lymphocytic leukemia (CLL)
usually asymptomatic but can present with weight loss, lymphadenopathy, and hepatosplenomegaly
what is the most common leukemia of adults in the western world
chronic lymphocytic leukemia (CLL)
what are the four pan B-cell markers expressed in CLL tumors
CD 5, 19, 20, and 23
how can chronic lymphocytic leukemia affect the spleen
causes small, white lesions that are scattered through the nodular areas of the white pulp
looks like sago spleen but sago spleen is caused by deposition of amyloid - nodules are more gray-translucent
what is the most common form of indolent non-hodgkins lymphoma in the US
follicular lymphoma
what does indolent mean
causing little or no pain
what causes follicular lymphoma
chromosomal
14:18 translocation
leads to overexpression of BCL2
what does BCL-2 do
anti-apoptotic protein seen in follicular lymphoma that promtoes the survival of follicular lymphoma cells
what is follicular lymphoma
type of peripheral B-cell neoplasm
germinal centers of nodes have many B cells that are not getting apoptosed as they should be
too much BCL-2
BCL-2 is expressed in more than what percentage of follicular lymphoma cases
90%
what lymphoid organs are most affected by follicular lymphoma
lymph nodes and bone marrow
can also been seen in liver and spleen sinusoids
what are the two major histomorphologic patterns seen in follicular lymphomas
centrocytes and centroblasts
what are centrocytes
small cells with irregular or cleaved nuclear contours and scant
seen in follicular lymphoma
what are centroblasts
larger cells with open nuclear chromatin, several nucleoli, and modest amount of cytoplasm
seen in follicular lymphoma
how does follicular lymphoma affect the spleen
white pulp follicles are expanded by follicular lymphoma cells
what is the most common form of non-hodgkin lymphoma
diffuse large B-cell lymphoma (DLBCL)
which sites are most affected by diffuse large B-cell lymphoma
extra nodal sites of the GI, CNS, skin, mediastinum, and bone
what chromosome abnormality is seen in 20-30% of diffuse large B-cell lymphoma cases
rearragnements of BCL2 and BCL6 genes
what are some features of diffuse large B-cell lymphoma
a type of peripheral B-cell neoplasm
presents as an enlarging mass at a node or extranodal site
have large cell size and diffuse pattern of growth
waldeyer ring commonly involved
very aggressive - 50% are cured with chemotheraphy
what is the waldeyer ring
oropharyngeal lymphoid tissue that includes the tonsils and adenoids
are the three main types of burkitt lymphoma
african (endemic)
sporadic (nonendemic)
subset of aggressive lymphomas
what are some features of burkitt lymphoma
a type of peripheral B-cell lymphoma
extremely fast growing
shows infiltrate of medium sized lymphoid cells with round nuclei and several nucleoli
high mitotic index with apoptotic cells
what causes burkitt lymphoma
caused by translocation of MYC gene on chromosome 8 which leads to increased MYC protein levels
almost all endemic Burkitt lymphomas are infected with which virus
EBV
what is the “starry sky” pattern and in which disease is it seen
macrophages that have phagocytosed oval nuclei with lots of nucleoli
seen in burkitt lymphoma
where are african (endemic) burkitt lymphoma cases mostly seen (3 places)
jaw, orbit, and retroperitoneal
where are sporadic (non-endemic) burkitt lymphoma cases mostly seen
GI tract, especially the ICV
what types of neoplasms are mantle and marignal cell lymphoma and hairy cell leukemia
peripheral B-cell neoplasms
what are three types of peripheral T and NK cell neoplasms
anaplastic large cell lymphoma
adult T-cell leukemia/lymphoma
mycosis fungoides/sezary syndrome
what is anaplastic large-cell lymphoma
a type of peripheral T and NK cell neoplasm
presence of rearrangements in the ALK gene
breast implant associated ALCL which is extremely rare
what is the incidence of breast implant associated ALCL
1 per 500,000-3 million women with implants
what is adult T-cell leukemia/lymphoma
a type of peripheral T and NK cell neoplasm
neoplasm of helper T cells that is only observed in adults infected with the human T-cell leukemia virus type 1
what was the first oncogenic human retrovirus to be discovered
adult T-cell leukemia/lymphoma
how is human T-cell leukemia virus type 1 (HTLV-1) spread
through blood, breast milk, and semen
what is mycosis fungoides/sezary syndrome
a type of peripheral T and NK cell neoplasm
primary cutaenous T-cell lymphoma seen in those that are 40+
tumor of helper T cells in the skin
what is multiple myeloma (plasma cell myeloma)
a type of plasma cell neoplasm where the mutated plasma cells make abnormal antibodies that harm the body
presents as tumor masses throughout the skeletal system
what are four symptoms of multiple myeloma
lytic bone lesions
hypercalacemia
renal failure
aquired immune abnormalities
how does multiple myeloma affect the kidneys
neoplastic plasma cells suppress normal humoral immunity and secrete partial immunoglobulins that are toxic to the kidney
excretion of bence jones proteins cause myeloma kidney
what is hodgkin’s lymphoma
lymphoma that arises in a single node or chain of nodes that spreads firm to anatomically contigous lymphoid tissues
diagnosed around 32 years
what is the distinctive feature of hodgkin’s lymphoma
reed-sternberg cells
what is one of the most common cancers of young adults and adolescents
hodgkin’s lymphoma
hodgkin’s lymphoma accounts for what percentage of all new cancers in the US
0.7%
what is the most common type (70%) of classic hodgkin lymphoma
nodular sclerosis
what are the five subtypes of hodgkin’s lymphoma
nodular sclerosis
mixed cellularity
lymphocyte rich
lymphocyte depletion
nodular lymphocyte predominance
