Wotherspoon criteria combined with B cell clonality analysis by advanced polymerase chain reaction technology discriminates covert gastric marginal zone lymphoma from chronic gastritis.
OBJECTIVE
Gastric mucosa associated lymphoid tissue lymphoma is a well defined B cell lymphoma yet often impossible to distinguish from severe chronic gastritis on morphological grounds alone. Therefore, it was suggested to use the clonality of the immunoglobulin (Ig) heavy chain (H) genes, as detected by polymerase chain reaction (PCR), as a decisive criterion. However, there is controversy as to whether B cell clonality also exists in chronic gastritis, hence rendering this approach futile at present.


METHODS
An expert panel re-examined the histology and immunohistochemistry of a total of 97 cases of gastric biopsies, including clearcut marginal zone lymphoma, chronic gastritis, and ambiguous cases, applying the Wotherspoon criteria on the basis of haematoxylin-eosin and CD20 immunostainings. In addition, a new and advanced PCR system for detection of clonal IgH gene rearrangements was independently applied in two institutions in each case.


RESULTS
The overall IgH clonality assessments of both institutions were in total agreement. Overt lymphoma (Wotherspoon score 5) was clonal in 24/26 cases. Chronic gastritis (Wotherspoon scores 1 and 2) was not clonal in 52/53 cases; the clonal case being Wotherspoon score 2. Of 18 cases with ambiguous histology (Wotherspoon scores 3 and 4) four were clonal.


CONCLUSIONS
Using advanced PCR technology, clonal gastritis is extremely rare, if it exists at all. Thus B cell clonality in Wotherspoon 3 and 4 cases is regarded as suitable for definitively diagnosing gastric marginal zone lymphoma.
Hummel
M
M
Institute of Pathology, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, D-12200 Berlin, Germany. Michael.Hummel@charite.de
Oeschger
S
S
Barth
T F E
TF
Loddenkemper
C
C
Cogliatti
S B
SB
Marx
A
A
Wacker
H-H
HH
Feller
A C
AC
Bernd
H-W
HW
Hansmann
M-L
ML
Stein
H
H
Möller
P
P
D000465:Algorithms; D018951:Antigens, CD20 / Q000378:metabolism; D014408:Biomarkers, Tumor / Q000378:metabolism; D002908:Chronic Disease; D002999:Clone Cells / Q000473:pathology; D003937:Diagnosis, Differential; D005756:Gastritis / Q000175:diagnosis* / Q000473:pathology; D015326:Gene Rearrangement, B-Lymphocyte, Heavy Chain; D005803:Genes, Immunoglobulin; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000235:genetics; D018442:Lymphoma, B-Cell, Marginal Zone / Q000175:diagnosis* / Q000473:pathology; D014411:Neoplastic Stem Cells / Q000473:pathology; D010865:Pilot Projects; D016133:Polymerase Chain Reaction / Q000379:methods; D015203:Reproducibility of Results; D013274:Stomach Neoplasms / Q000175:diagnosis* / Q000473:pathology
D018951:Antigens, CD20; D014408:Biomarkers, Tumor; D007143:Immunoglobulin Heavy Chains