Lymph Node Pathology and Lymphoma Overview

Lymphadenopathy

Enlargement of lymph nodes due to various causes.

Benign Lymphadenopathy

Lymph node enlargement due to non-cancerous conditions.

Malignant Lymphadenopathy

Lymph node enlargement due to cancerous conditions.

Painful Lymphadenopathy

Lymph node enlargement due to acute inflammation.

Painless Lymphadenopathy

Lymph node enlargement due to chronic inflammation or malignancy.

Lymphoma

Cancer of lymphatic system; includes Hodgkin and Non-Hodgkin.

Hodgkin Lymphoma (HL)

Characterized by Reed-Sternberg cells; localized spread.

Non-Hodgkin Lymphoma (NHL)

Diverse group; non-contiguous spread; can involve extranodal sites.

Reed-Sternberg Cells

Abnormal cells found in Hodgkin Lymphoma.

Cytogenetic Abnormalities

Genetic mutations associated with specific lymphomas.

Follicular Lymphoma

Associated with t(14;18) chromosomal translocation.

Burkitt Lymphoma

Associated with t(8;14) chromosomal translocation.

Mantle Cell Lymphoma

Associated with t(11;14) chromosomal translocation.

Hodgkin Lymphoma Cytogenetics

No characteristic cytogenetic abnormalities identified.

Bimodal Distribution

HL incidence peaks in young adults and >55 years.

Constitutional Symptoms

Symptoms like fever, night sweats, weight loss in HL.

Acute Inflammation

Body's immediate response to injury, causing pain.

Chronic Inflammation

Long-term inflammation, often painless lymphadenopathy.

Tumor Mass Composition

HL mass includes Reed-Sternberg cells and fibrosis.

Prognosis in HL

Stage is strongest predictor; often good outcomes.

Prognosis in NHL

Varies; can be good, bad, or ugly.

Leukemic Phase

Presence of leukemia-like symptoms in some NHL.

EBV Association

Epstein-Barr Virus linked to Hodgkin Lymphoma.

Hodgkin Lymphoma

No characteristic cytogenetic abnormalities present.

Chronic Myeloid Leukemia (CML)

Characteristic t(9;22) chromosomal translocation.

Gastric MALToma

Type of lymphoma responsive to antibiotic therapy.

Burkitt Lymphoma

Aggressive B-cell lymphoma, often associated with EBV.

Small Lymphocytic Lymphoma

Indolent lymphoma, often presents with lymphadenopathy.

Nodular Sclerosis

Most common subtype of Hodgkin Lymphoma (65%-70%).

Lacunar Cells

Diagnostic neoplastic cells in Hodgkin Lymphoma.

Cervical Lymphadenopathy

Swelling of cervical lymph nodes, often indicative of lymphoma.

Mediastinal Involvement

Common in Nodular Sclerosis subtype of HL.

Fibrous Bands

Structure forming nodules in Nodular Sclerosis subtype.

Female Predominance

More common in females, especially in Hodgkin Lymphoma.

Myelofibrosis

Possible complication in Hodgkin Lymphoma patients.

Monomorphic Population

Uniform cell type observed in lymph node biopsy.

CD20

Surface marker commonly expressed in B-cell lymphomas.

CD19

B-cell marker used in lymphoma diagnosis.

CD10

Marker indicating germinal center B-cells.

TdT

Marker indicating immature lymphoid cells.

Surface Kappa Light Chain

Indicates B-cell clonality in lymphomas.

Anemia

Common finding in lymphoma patients, indicating systemic effects.

Waldeyer Ring

Lymphoid tissue in the oropharynx, often involved in lymphoma.

Enlarged Supraclavicular LN

Sign of possible malignancy, including lymphoma.

Lymphoblastic Lymphoma

Type of lymphoma associated with immature T-cells.

Diffuse Large B Cell Lymphoma (DLBCL)

Most common aggressive lymphoma in adults.

Follicular Lymphoma

B-cell neoplasm with follicular growth pattern.

Small Lymphocytic Lymphoma (SLL)

Lymphoma variant of chronic lymphocytic leukemia.

Diffuse Large B Cell Lymphoma

Aggressive B-cell lymphoma with diffuse growth.

Hodgkin Lymphoma

Characterized by Reed-Sternberg cells.

Reed-Sternberg Cell

Classic cell type in Hodgkin Lymphoma.

Germinal Center B-cell

B-cell in lymphoid follicles, PAX5 positive.

PAX5

Transcription factor expressed in B cells.

CD20

Surface marker typically absent in germinal center B-cells.

CD45

Common leukocyte antigen, negative in germinal center B-cells.

CD30

Surface marker associated with Reed-Sternberg cells.

CD15

Surface marker often expressed in Hodgkin Lymphoma.

WHO Classification

System for categorizing hematopoietic tumors.

Clonal Rearrangement

Genetic alteration indicating neoplastic proliferation.

t(9;22)

Chromosomal translocation linked to BCR-ABL in CML.

t(14;18)

Translocation associated with BCL2 overexpression in Follicular Lymphoma.

t(8;14)

Translocation leading to C-MYC overexpression in Burkitt Lymphoma.

Chronic Lymphocytic Leukemia (CLL)

B-cell neoplasm with small, mature lymphocytes.

Smudge Cells

Disrupted tumor cells seen in CLL smears.

Lymphocytosis

Increased lymphocyte count in peripheral blood.

Anemia

Low hemoglobin level, indicated by Hb: 9.5 g/dL.

Thrombocytopenia

Low platelet count, indicated by Plt=120,000/mm3.

Leukocytosis

Increased white blood cell count, indicated by WBC=42,000.

Autoimmune Hemolytic Anemia

Condition causing spherocytes in CLL.

Nucleated Erythroid Cells

Cells indicating marrow infiltration or anemia.

Lymph Node Biopsy

Diagnostic procedure to assess lymph node pathology.

Malignant lymphoma

Cancer of lymphatic tissues with abnormal cell growth.

Monoclonality

Derived from a single transformed cell.

Kappa light chains

Type of immunoglobulin light chain in B cells.

Lambda light chains

Another type of immunoglobulin light chain in B cells.

Light chain restriction

Presence of only one type of light chain.

Polyclonal

Mixture of multiple B cell types.

T cell receptor gene rearrangements

Indicates clonal expansion in T cell neoplasms.

Burkitt lymphoma

High-grade lymphoma associated with MYC translocation.

t(8;14)

Translocation involving MYC gene in Burkitt lymphoma.

Extranodal

Lymphoma occurring outside lymph nodes.

Growth fraction

Percentage of cells in the cell cycle.

S-phase

Phase of the cell cycle for DNA synthesis.

Cervical lymphadenopathy

Swelling of cervical lymph nodes.

Intermediate-sized lymphoid cells

Lymphoma cells with moderate size and features.

Coarse chromatin

Nuclear feature indicating active cell division.

Numerous mitoses

High cell division rate in tumor pathology.

Firm, nontender lymph nodes

Physical exam finding in lymphoma cases.

CD30 antigen

Marker used to identify certain lymphomas.

Germinal centers

Sites of B cell maturation in lymph nodes.

Flow cytometry (FCM)

Technique to analyze cell populations by surface markers.

Endemic Burkitt lymphoma

Form associated with EBV, common in Africa.

Sporadic Burkitt lymphoma

Form not associated with EBV, seen globally.

Chemotherapy response

Effectiveness of treatment based on tumor growth rate.

Lymph node biopsy

Procedure to diagnose lymphoma through tissue sampling.

Burkitt Lymphoma

Endemic form presents with jaw/orbital lesions.

c-MYC gene

Translocated on chromosome 8 in Burkitt lymphoma.

Translocation t(8;14)

c-MYC gene partners with IgH locus.

Starry sky pattern

Result of numerous tingible-body macrophages.

Follicular Lymphoma

Indolent lymphoma with generalized lymphadenopathy.