The document discusses metastasis to lymph nodes, focusing on its incidence, differentiation from lymphoma, and the significance of lymph node assessment for cancer staging. It highlights the TNM staging system and the role of lymph nodes in determining the extent of cancer, including various primary tumor sites and their association with lymphatic spread. Additionally, it describes methods to distinguish between lymphomas and malignant carcinomas using various staining techniques and immunocytochemistry.

1. METASTATIC TUMORS TO LYMPH
NODE
Dr.Dur-e-Zahra
M.Phil Haematology

2. LEARNING OBJECTIVES
• Introduction to metastasis to lymph nodes
• Incidence of metastasis of Ca to lymph nodes
• Differentiate Lymphoma from Metastasis to lymph
node
• TNM staging

3. LYMPH NODE METASTASIS
• Most common site of metastatic malignancy
• Presence of metastasis is important for TNM staging
• Usually first clinical manifestation of disease
• Every lymph node enlargement calls for assessment by
pathologist whether its benign or malignant

4. MUST DETERMINE WHILE EXAMINING
A LYMPH NODE
Tumor Present or Not
Tumor Primary or
Metastatic
Possible sites of
Primary Tumor
Number of Metastatic
nodes involved
Presence of Extranodal or
Vascular involvement

5. INCIDENCE OF LYMPH NODE
METASTASIS
Carcinomas
Malignant melanoma
Germ cell tumors
Sarcoma
CNS
tumors

6. METASTATIC TUMOR VS LYMPHOMA
METASTATIC LYMPH NODE LYMPHOMA
Cohesive tumor cells with well
clearly defined margins
Multifocal with diffuse penetration of
vessel wall
Sinus involvement Not limited to sinuses
Extensive necrosis No necrosis seen
Solid tumor plugs in lymphatic
vessels
Tumor plugs not common

7. TUMORS SIMULATING LYMPHOMA
• Nasopharyngeal carcinoma - undifferentiated (tumor cells mix
with lymphocytes and tumor does not appear cohesive)
• Melanoma (tumor cells separate from each other within clusters)
• Breast lobular carcinoma (may appear noncohesive)
• Seminoma (inguinal and abdominal nodes)

8. LYMPHOMA SIMULATING AS
METASTATIC CANCER
• Anaplastic large cell lymphoma
• Large B cell lymphoma
• Hodgkins lymphoma
• Composite lymphoma

9. HOW TO DIFFERENTIATE LYMPHOMA
FROM MALIGNANT CARCINOMA
• Mucin stain
• PAS stain
• Touch cytology
• Reticulin stain
• Immunocytochemistry

10. IMMUNOCYTOCHEMISTRY
Primary markers
CD45/LCA
Pancytokerati
n
S-100
Secondary markers
CD3(T-cell)
CD20(B-
cells)
EMA
CEA
Vimentin
PSA/PAP

11. SITE OF METASTASES
• Upper cervical nodes : associated with upper aerodigestive tract
• Midcervical nodes : thyroid carcinoma, salivary gland, upper aerodigestive
tract; also thymus or ovary
• Supraclavicular nodes : breast or lung, also stomach, pancreas, prostate,
testis
• Axillary nodes : breast (women), melanoma, lung
• Inguinal nodes : external genitalia, melanoma
• Undetectable primaries with nodal metastases : nasopharynx,
retrotonsillar pillars

12. RESECTED
LYMPH NODE
SPECIMEN.
• A) 45mm yellowish
lobular structure can be
seen in the resected
lymph node
• B) The typical trabecular
structure pattern of
hepatocellular carcinoma
was confirmed
microscopically

15. GOOD TO
KNOW!
• Supraclavicular nodes
involved by intra-
abdominal carcinomas
are sometimes referred
to as Virchow or
Troisier nodes

16. SYSTEM FOR STAGING CANCER
• Lymph nodes play an important role in cancer staging,
which determines the extent of cancer in the body.
• The most commonly used systems for staging cancer is
the TNM system.
• It is based on the extent of the tumor (T), the extent of
spread to the lymph nodes (N), and the presence of
metastasis (M).

17. THE “N” IN TNM
SYSTEM
• If no cancer is found in the lymph nodes
near the cancer, the N is assigned a value
of 0.
• If nearby or distant nodes show cancer,
the N is assigned a number (such as 1, 2
or 3), depending on
 how many nodes are affected,
 how much cancer is in them,
 how large they are,
 and where they are located.