This document provides guidelines for the pathological diagnosis of lymph node biopsy specimens. It discusses the importance of adequate biopsy samples and multidisciplinary evaluation. Common non-neoplastic conditions that can cause lymphadenopathy like infections are reviewed. The key aspects of lymph node anatomy are summarized. The pathological approach involves first determining if the process is non-neoplastic or neoplastic. If non-neoplastic, patterns like follicular hyperplasia or sinus histiocytosis are considered. Specific granulomatous and inflammatory conditions are also discussed. If neoplastic, the document reviews distinguishing features of common lymphoma subtypes. Immunohistochemistry to characterize lymphomas using markers like CD20 and Bcl2 is also mentioned.

1. APPROACH TO DIAGNOSIS OF
LYMPH NODE
Neema Tiwari

2. REPORTING GUIDELINES FOR LYMPH
NODE BIOPSY
• Each MDT[MULTIDISCIPLINARY TEAM MEETING]
should have at least one identified pathologist
who will review material from all new
• The final report should integrate all investigations
carried out on the sample
• Specialist areas such as paediatrics and
neuropathology should refer lymphoma cases for
review by specialist haematopathologists

3. PROCESSING

4. Diagnosis requires an adequate biopsy
• Diagnosis should be biopsy-proven before
treatment is initiated
• Need enough tissue to assess cells and
architecture
– open bx vs core needle bx vs FNA

5. CLINICAL APPROACH

6. CLINICAL APPROACH

8. Evaluation of Suggestive S & S Associated with Lymphadenopathy
Mononucleosis-type
syndromes
Fatigue, malaise, fever, atypical
lymphocytosis
Epstein-Barr virus* Splenomegaly in 50% of patients Monospot, IgM EA or VCA
Toxoplasmosis* 80 to 90% of patients are
asymptomatic
IgM toxoplasma antibody
Cytomegalovirus* Often mild symptoms; patients may
have hepatitis
IgM CMV antibody, viral
culture of urine or blood
Initial stages of HIV
infection*
"Flu-like" illness, rash HIV antibody
Cat-scratch disease Fever in one third of patients; cervical
or axillary nodes
Usually clinical criteria; biopsy
if necessary
Pharyngitis due to group A
streptococcus,
gonococcus
Fever, pharyngeal exudates, cervical
nodes
Throat culture on appropriate
medium
Tuberculosis lymphadenitis* Painless, matted cervical nodes PPD, biopsy
Secondary syphilis* Rash RPR
Hepatitis B* Fever, nausea, vomiting, icterus Liver function tests, HBsAg

9. Unexplained Lymphadenopathy
Generalized Lymphadenopathy
• almost always indicates a systemic disease is present,
proceed with specific testing as indicated.
• If a diagnosis cannot be made, the clinician should obtain a
biopsy of the node.
• The diagnostic yield of the biopsy can be maximized by
obtaining an excisional biopsy of the largest and most
abnormal node
• The physician should not select inguinal and axillary nodes for
biopsy, since they frequently show only reactive hyperplasia

10. Unexplained Lymphadenopathy
Localized Lymphadenopathy
 Patients with a benign clinical history, an unremarkable physical
examination and no constitutional symptoms should be reexamined in
three to four weeks to see if the lymph nodes have regressed or
disappeared.
 Patients with unexplained localized lymphadenopathy who have
constitutional symptoms or signs, risk factors for malignancy or
lymphadenopathy that persists for three to four weeks should undergo a
biopsy.

11. Unexplained Lymphadenopathy
Localized Lymphadenopathy
 Biopsy should be avoided in patients with
probable viral illness because lymph node
pathology in these patients may sometimes
simulate lymphoma and lead to a false-
positive diagnosis of malignancy.

12. PATHOLOGICAL DIAGNOSIS
• NORMAL ANATOMY
• PATHOLOGICAL DISEASE-
 Non neoplastic lymph node lesion
 Neoplastic lesion

13. Lymph node anatomy
• To recognize
lymph node
pathology,
one has to
be familiar
with normal
lymph node
anatomy
and cytology

15. Cell types I
• Small lymphocytes
– Small round dark blue dots. Round
nucleus, clumped chromatin, small or
absent nucleolus.
– Locations:
• B cells- primary follicles, mantle
zone of secondary follicles,
medullary cords
• T cells- paracortex, minor
population within germinal center.
– Kinetically, clumped chromatin tells us
that the cell is not proliferating- not
activated to enter the cell cycle and
replicate

16. Cell types 2:Follicular (germinal)
center cells
• Replicating and post-replicating B cells
– Noncleaved cells, small and large
• Replicating populations-
expanding antigen responsive
cells.
• Round nuclei but larger than
resting small lymphocyte
• Open or vesicular chromatin
• Recognizable nucleoli.
– Nucleus clear -->genetic
material unwound for
replication.
• Size, large or small compared
nucleus of macrophage.
– Small cleaved cells-
• Nonreplicating population
• Post mitotic memory or plasma
cell precursors
• Clumped chromatin
• Irregular folded and cleaved
nuclear profiles

17. Cytology of lymph node 3
• Immunoblasts
– Replicating large cells found
outside the germinal centers.
– May be of B or T cell type
– Have nuclear characteristics of
replicating lymphocytes-
• Vesicular chromatin
• Nucleoli
• Accessory cells
– Antigen processing cells
• Interdigitating reticulin cells- T cell
paracortex
• Dendritic reticulin cells- B cell germinal
centers
• Process and present antigen to B and T
lymphocytes
• Invisible in normal lymph node
– Macrophages (histiocytes)-
• Phagoctytic cells of lymph node
• Tingible body macrophages of germinal
centers
• Medullary and subcapsular sinus
macrophages-
• Abundant pale cytoplasm
• Oval nucleus, single small nucleolus

18. PATHOLOGICAL APPROACH

19. 1]NON-NEOPLASTIC LESION
2]NEOPLASTIC LESION

20. APPROACH TO HISTOLOGY

21. NON NEOPLASTIC

23. APPROACH CONT. -FOLLICULAR AND
NODULAR PATTERN
1] Are they follicles or nodules-stain for FDC
2]Follicles reactive or neoplastic
3]Follicles are infrequent or regressed-
MCL,MZL,HL
4]How many layers in follicle
5]Follicles exceptionally large-Differentiate PTGC
from NLPHL
6]Enlarged germinal centers contain atypical
cells-

24. CONT..
• Enlarged germinal centers contain atypical
cells
• Are the nodules homogenous or
heterogeneous in composition-
distending sinus-mcl,mzl
Heterogeneous nodules
• Marked follicular hyperplasia with specific
diagnosis
• Non neoplastic granulomatous lymphadenitis
• Marked Necrosis

25. REACTIVE LYMPH NODE

26. SINUS PATTERN

28. ROSAI DORFMAN

29. REACTIVE LN WITH FOCAL NECROSIS

30. PTGC
• Adults and adolescents
• Solitary painless cervical
swelling
• Runs for a long period
• No synchronous or
metachronous
appearance like in NHL

31. RHEUMATOID LYMPHADENOPATHY
• Hyperplastic follicles are
seen in both the cortex
and medulla of the
lymph node.
• narrowing of the mantle
zones.

32. TOXOPLASMA LYMPHADENITIS
• mixed pattern of
follicular hyperplasia
and monocytoid B cell
hyperplasia.
• small to large clusters of
epithelioid histiocytes
scattered throughout
the lymph node with
encroachment on GC

33. HIV LYMPHADENOPATHY

34. KIMURAS DISEASE
 Self-limiting disease, common to
Orientals, male predominance
 Mixed hyperplasia of follicles and
paracortex
 Enlarged germinal centers
contain,proteinaceous material
 Eosinophils in paracortex and
sinuses, for microabscesses
 Plasma cells, small lymphocytes,
mast cells, and vessels in
paracortex
 Occasional Warthin–Finkeldey
giant cells

35. SYPHILIS LYMPHADENITIS
• marked follicular
hyperplasia that extends
throughout the lymph node
• prominent paracortical
hyperplasia.
• marked fibrosis of the
• arteritis and phlebitis
• Prominent perivascular cuff
of plasma cells and
lymphocytes, and
• Small non-caseating
granulomas
• naked giant cells.

36. KIKUCHI-FUJIMOTO DISEASE
• asian ,young
• Early phase changes
non-specific lymphoid
hyperplasia
• Paracortical B and T cell
blasts prominent
• Focal areas of apoptosis
• Absence of neutrophils;
plasma cells uncommon

37. CASTLEMANS DISEASE-HYALANIZING
TRABECULAR VAR.
• Benign cured by excision, solitary mode young
adults asymptomatic.
• Broad mantle zone with onion skinning-enlarged
follicles and collagenised vessels in germinal
centers.
• Lollipop appearence
• Thick interfollicular vessels,small lymphocytes,
plasma cells.
• Plasmacytoid monocytes may be prominent.
• CD21 expanded concentric meshwork of FDC

39. PLASMA CELL VARIANT

41. MULTICENTRIC TYPE

43. INFECTIOUS MONONUCLEOSIS

44. DIFFUSE INFILTRATE OF LN
• Is the infiltrate truly diffuse
• Infiltrate involving the node completely or
partially-
 Leukemic infiltrate- sinuses
 T cell lymphomas –paracortex
• Monomorphous or polymorphous
• Cells small or large or intermediate

45. GRNULOMATOUS LYMPHADENITIS
• MYCOBACTERIAL-Necrotising lesion , AFB seen,
epitheloid cells sheets of histiocytes.
• CAT –SCRATCH DISEASE-[B.henslae]-Granulomas with
stellate necrosis,pleomorphic rod shaped bacilli stained
by Warthin-Starry stain
• LYMPHOGRANULOMA VENERUM-Suppurative
granulomas with foamy macrophages filled with sand like
organisms stained by warthin
• YERSINIA LYMPHADENITIS-Abdominal LN,small
necrotising LN

46. CAT SCRATCH
• Cat-scratch disease is
caused by a small,
pleomorphic, gramnegative
bacterium, Bartonella
henselae (previously
Rochalimaea
• There is often a recent
history of contact with a cat
or kitten.
• sheets of histiocytes/
macrophages, often
arranged as discrete
granulomas with central
necrosis.

47. LYMPHOGRANULOMA VENERUM
• necrotizing granulomas commence as small necrotic foci with collections
of neutrophils followed by plasma cells and lymphocytes
• Coalescing of these foci produces a stellate pattern of necrosis within the
granulomas.
• sections occur within vacuolate macrophages that accumulate in necrotic
or suppurative foci.
• They can be stained with the Warthin–Starry stain and confirmed by the
polymerase chain reaction.
• There is a background of follicular hyperplasia with clusters of monocytoid
B cells in the cortex.
• Vascular endothelial cells may be prominent; there is capsular fibrosis and
capsular vessels may show vasculitis

49. WHIPPLES DISEASE

50. NON INFECTIVE GRANULOMAS
• KIKUCHI-FUJIMOTO-Necrotising grnulomas
without neutrophils
• SLE-Necrotising granulomas,no neutrophils
and eosinophils,plasma cells present
• SARCOIDOSIS-Discrete
granulomas,schaumann asteroid,Hamazaki-
wesenberg bodies,cal. Oxalate crystals
• KAWASAKI-Mucocutaneous
lesion,necrosis,fibrin thrombi,neutrophils

51. SARCOIDOSIS

53. FUNGAL-HISTOPLASMA

54. HISTOPLASMA

55. CRYPTOCOCCUS LYMPHADENITIS

56. PARASCITIC

57. PARASCITIC

58. FBG-SILICONE LYMPHADENITIS

59. SILICONE LYMPHADENITIS

60. NEOPLASTIC LESION

62. LYMPHOMA PANEL

64. T-CELL MARKERS

65. Follicular lymphoma
Bcl2
CyclinD1
Mantle cell lymphoma

67. • THANKYOU