Prognostic sub-grouping of diffuse large B-cell lymphomas into germinal centre and post germinal centre groups by immunohistochemistry after 6 cycles of chemotherapy.
BACKGROUND
Diffuse large B-cell lymphomas (DLBCL) can be divided into germinal centre (GC-DLBCL) and post germinal centre (post GC-DLBCL) groups by applying immunohistochemical antibodies. As these subgroups respond differently to chemotherapy, it is possible at diagnosis to select a poor prognostic subgroup for aggressive treatment.


OBJECTIVE
To determine the frequencies of GC-DLBCL and post GC-DLBCL in patients by immunohistochemistry (IHC) and the clinical response after six cycles of chemotherapy.


METHODS
In this descriptive study conducted in AFIP and CMH, Rawalpindi and NORI, Islamabad, from September 2010 to September 2011, a total of 75 pretreatment cases of DLBCL diagnosed during the study period were included. Cases were segregated in to GC-DLBCL and post GC-DLBCL groups according to results of immunohistochemistry markers CD10, BCL6 and MUM1. Immediate clinical response was assessed after 6 cycles of chemotherapy. Response was divided into complete response, partial response, stable disease or relapse or progression.


RESULTS
The mean age was 54.2 ± 15. Males were 53 (70.7%). Forty (53.3%) cases comprised the GC-DLBCL group; 25(62.5%) of them showed a complete response. Most patients of the post GC-DLBCL 19(54%) showed relapse/progression. Results of immediate clinical response in both prognostic subgroups were significant (p<0.05). Results regarding positivity with immunohistochemical antibodies CD10 (p 0.011), BCL6 (p 0.013) and MUM1 (p 0.000) regarding immediate clinical response were also significant.


CONCLUSIONS
GC-DLBCL group shows better response to CHOP chemotherapy regimen. Immunohistochemistry should be used to further classify DLBCL as this can enable us to select aggressive group for aggressive treatment. This manuscript is important because the study is the first to becarried out exclusively in Pakistan or our part of the world.
Department of Histopathology, Armed Forces Institute of Pathology, Lahore Pakistan. usman_hassan256@hotmail.com
Usman
U
Hassan
Sajid
S
Mushtaq
Nadira
N
Mamoon
Asghar Hussain
AH
Asghar
Sheeba
S
Ishtiaq
D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage / Q000627:therapeutic use; D014408:Biomarkers, Tumor / Q000378:metabolism*; D003520:Cyclophosphamide / Q000008:administration & dosage; D004268:DNA-Binding Proteins / Q000378:metabolism; D004317:Doxorubicin / Q000008:administration & dosage; D005260:Female; D018858:Germinal Center / Q000145:classification* / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D050835:Interferon Regulatory Factors / Q000378:metabolism; D016403:Lymphoma, Large B-Cell, Diffuse / Q000145:classification* / Q000188:drug therapy / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D015260:Neprilysin / Q000378:metabolism; D010154:Pakistan; D018579:Patient Selection; D011239:Prednisolone / Q000008:administration & dosage; D011379:Prognosis; D051560:Proto-Oncogene Proteins c-bcl-6; D016896:Treatment Outcome; D014750:Vincristine / Q000008:administration & dosage; D000099218:Interferon Regulatory Factor-4
D014408:Biomarkers, Tumor; D003520:Cyclophosphamide; D004268:DNA-Binding Proteins; D004317:Doxorubicin; D050835:Interferon Regulatory Factors; D015260:Neprilysin; D011239:Prednisolone; D051560:Proto-Oncogene Proteins c-bcl-6; D014750:Vincristine; D000099218:Interferon Regulatory Factor-4; C084103:BCL6 protein, human