| What is benign lymphadenopathy? | Inflammation of lymph nodes characterized by cortical/paracortical hyperplasia.
Usually caused by acute infections (strep, staph most common/bartonella (cat-scratch)/tularemia (rabbits))
Most frequent presentation is enlarged tender nodes, site depends on nature of disease. |
| What is malignant lymphadenopathy? | Chronic non-specific lymphadenitis (long-standing non tender adenopathy)
Etiologies include autoimmune, HIV, chronic infections, and drugs |
| What are lymphoid neoplasms? | ALL/CLL, non-hodgkins lymphoma (follicular, diffuse large B-cell, or Burkitt lymphoma), Hodgkins lymphoma and plasma cell disorders. |
| What is non-Hodgkin's lymphoma? | Usually of B cell origin (T cell are much rare), present with widespread lymphadenopathy, B symptoms (fever, weight loss, night sweats).
Spread non-contiguously and often involves extranodal sites.
CD markers (used in immunohistochem and flow cytometry, B cells CD19 and 20, plasma cells CD138 k and lambda, CD3,5 for T cells) |
| What is NHL follicular lymphoma? | Most carry t(14;18), juxtaposed BCL-2 gene w/Ig heavy chain gene, this causes unregulated expression of BCL-2 an inhibitor of apoptosis and thus increased survival of germinal centers leading to lymphoma.
So we have replacement of lymph nodes with enlarged follicles consisting of small cleaved lymphocytes
Most common NHL, presents middle age, fairly indolent survival 8 years but not amenable to chemo, 30-50% transform to more aggressive large B-cell lymphomas [not richter syndrome] |
| What is the difference between reactive lymphoid hyperplasia and follicular lymphoma? | Lymphoid hyperplasia (low power magnification, B cell follicle strongly express II spectrin, numerous tingible body macrophages in germinal center appear negative)
Follicular lymphoma (low-power magnification, positive II spectirn staining neoplastic B cell nodule) |
| What is NHL diffuse large B-cell lymphoma? | 30% carry t(14;18) indicating transformed follicular lymphoma, 20-30% carry translocations involving BCL-6 gene in B cell differentiation.
It is common in immunodeficiencies a result of transformation of lymphocytes due to EBV or HHV-8 infection
It is diffuse replacement of lymph node parenchyma with large pleomorphic cells
Usually older pts but has a wide age range including children, usually present w/rapidly enlarging mass at either a nodal or extranodal site.
Symptoms if present are usually due to mass effect or tissue destruction.
Very aggressive but responds to chemo w/lasting remission seen in 50% of pt |
| What is NHL Burkitt lymphoma? | Endemic and sporadic forms w/EBV infection, most carry translocations involving C-myc gene on chrmsm 8, most of these is t(8;14) putting C-myc gene with heavy chain gene, leads to unregulated overexpression of C-myc promoting cell growth and division.
Diffuse infiltrates of medium sized cells, large numbers of mitotic and apoptotic cells, scattered benign macrophages (Starry sky) |
| How is clinical presentation of Burkitt lymphoma? | All forms occur at extranodal sites, 3 types (Endemic [africa; mostly mandible], Sporadic [abdominal mass], HIV-assocaiated [very aggressive]
Most frequently seen in children and young adults, HIV -associated forms w/any age, generally very aggressive but responds well to short term high dose chemo |
| What is Hodgkin's lymphoma? | In contrast w/NHL, typically presents in a single node or several adjacent lymph nodes, confined to lymph nodes, seldom w/extranodal component, spreads in a contiguous fashion (one node to adjacent), consists of few neoplastic cells (Reed-Sternberg RS cells) surrounded by many benign reactive cells
Little knowledge about etiology, some show evidence of EBV infection (RS cells) and cytogenetic abnormalities, surrounding inflammatory stroma results from expression of cytokines [IL and TNF] from RS cells. |
| What are subtypes of HL? | . |
| What are Reed-Sternberg cells and variants? | Classic ones are large (14-45 microm) w/abundant pale cytoplasm and two or more oval lobulated nuclei containing owl-eye eosinophilic nucleoli.
Some shrink during formaline fixation and processing leave empty space around nucleus, called Lacunar cells.
Other variant is L&H and Popcorn cell w/fluffy lobulated nucleus containing fine chromatin and small nucleoli |
| How is HL tumor staging? | . |
| How is clinical presentation of HL? | Enlarging lymphadenopathy w/or w/out B symptoms, prognosis depends on stage generally good, even stage IV has 60-70% 5-year survival, CD markers CD15, CD30 (+) CD20 CD45 (-) except nodular lymphocyte predominant form (becomes reveresed) |
| What are plasma cell neoplasms? | Secrete monoclonal Igs, include plasma cell myeloma, plasmacytoma, MGUS, lymphoplasmacytic lymphoma (Waldenstrom macroglobulinemia) |
| What is multiple myeloma plasma cell neoplasm? | Secrete monoclonal Ig M protein (not IgM, heavy (IgG and IgA) and light chains (kappa and lambda), free light chains (Bence-Jones protein)
We see gamma globulin spike in serum electrophoresis. |
| Describe and specify pathologies of serum protein electrophoresis? | a 1 zone (orosomucoid and antitrypsin, but mostly antitrypsin. decreased band in nephrotic syndrome, and AAT deficiency, leads to emphysema from unregulated lung elastase breakdown by neutrophils in lung tissue, AAT increased in positive acute phase reactant acute inflammation, bound by Bence Jones protein)
a2 zone (principally of a2 macroglobulin AMG and haptoglobin, typically low levels of hemolytic anemia, raised in acute phase response during inflammation) |
| What are features of multiple myeloma? | Increased abnormal plasma cells, monoclonal gammopathy (light chain restriction), lytic bone lesions (punched out) |
| What is plasma cell myeloma? | Bone marrow plasma cell infiltration (chronic pain, pathologic features, and hypercalcemia)
Increased Ig production and amyloid deposition
Impaired immunity (recurrent infections)
Clinically (seen in pt >50 yrs old, incidence increased w/age, prognosis not very good range from 3-6 years depending on cytogenetics)
Variants (smoldering, indolent, osteosclerotic, non secretory (rare, negative for M protein in urine and serum, has all other characteristics of multiple myeloma)
Solitary lesion is monoclonal neoplastic plasma cells, top sites bone marrow [intramedullary], extramedullary [URT].
Bone plasmacytomas progress to plasma cell myeloma w/in 10-20 years, extraosseous plasmacytomas rarely progress and can be surgically cured. |
| What is plasma cell neoplasm MGUS? | Monoclonal Gammopathy of undetermined significance, serum monoclonal M protein but no other signs or symptoms of myeloma, found in 1% of people >50 yrs old and increases w/age, only a small percentage ever progresses to overt myeloma. |
| What is lymphoplasmacytic lymphoma? | Waldenstrom' macroglobulinemia, neoplastic B cells secrete IgM monoclonal, elevated serum IgM causes hyperviscosity syndrome (visual impairment, neuro problems and bleeding)
Patients also present w/hepatosplenomegaly, lymphadenopathy and anemia, disorder is progressive and incurable, median survival is 4 years |
