Ann. Pak. Inst. Med. Sci. 2010; 6(1): 31-35

Objective: To determine response and relapse rates in diffuse large B cell lymphoma (DLBCL) patients receiving rituximab, cyclophosphamide, adriamycin, vincristine and prednisolone (R-CHOP) versus cyclophosphamide, adriamycin, vincristine and prednisolone (CHOP).
Study Design: RC T (Randomized Control Trial).
Materials and Methods: This Randomized Control Trial was conducted between April 2007 and December 2008. 119 newly diagnosed consecutive DLBCL patients were treated with either R-CHOP or CHOP as first line chemotherapy at the Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH & RC), Lahore, Pakistan. The CHOP chemotherapy was offered to 63 patients (53%) and 56 patients (47%) were given R-CHOP therapy. The arms were balanced with respect to International Prognostic Index (IPI) score, stage, and B symptoms (presence of systemic complaints of fever, weight loss, or night sweats).
Results: The response rates in terms of (disappearance of all radiological or biological lesions at the time of initial diagnosis and the absence of new lesions) were 48 % vs. 44% (p= 0.715) in R-CHOP and CHOP groups, respectively. Whereas the relapse rates were 9% vs. 20% (p=0.04) in R-CHOP and CHOP groups, respectively.
Conclusion: The addition of rituximab to CHOP chemotherapy increased the event free interval compared to CHOP chemotherapy in DLBCL Pakistani patients. However, it did not show any influence in response rate in this population.
Key words: Diffuse Large B Cell Lymphoma (DLBCL), Rituximab, CHOP (cyclophosphamide, adriamycin, vincristine and prednisolone)

Introduction


Diffuse Large B Cell Lymphoma (DLBCL) is the most common Non Hodgkin’s Lymphoma and accounted for 40 % of the newly diagnosed lymphomas.¹ In 1993, the US Intergroup study demonstrated that the CHOP regimen (cyclophosphamide, doxorubicin, vincristine, prednisone) was associated with similar complete response (CR) rates, progression-free survival (PFS), and overall survival (OS) compared with more complicated regimens associated with more toxicity.²
CD 20 is an antigen that is expressed by DLBCL. Rituximab, a chimeric monoclonal antibody against the CD20 B-cell antigen, has therapeutic activity in diffuse large-B-cell lymphoma. R-CHOP (Rituximab, Cyclophosphamide, Doxorubicin, prednisolone and vincristine) has become the standard of care for DLBCL.³
In limited stage disease (stage I) with an adverse prognostic factor ISI (International Prognostic Index) score or non bulky stage II disease the addition of Rituximab to CHOP Chemotherapy and involved field radiation did not have an impact on the overall survival. The impact of Rituximab in a limited-stage setting was smaller than in advanced-disease setting, and there was a 4% absolute difference in 4-year OS as opposed to 10% to 15% absolute difference in 5-year OS in advanced disease, although the relative difference was 33%, which was more in line with reduction seen in advanced disease.⁴
Rituximab when added to CHOP chemotherapy is reported to have an increase in the overall response rate as well as overall survival in DLBCL,³ but in another study it did not have an impact on the response rate but when given as a sequential therapy in patients who had received CHOP before, it did have an impact on the overall survival.⁵ In all these studies the target population was above 60 years of age.^3,5
Due to the overall increase in the amount of diagnostic facility and good cancer centers now available, the deaths due to cancers are decreasing. The down side includes the increased cost and serious financial burden to patients, and their families.⁶
Due to high cost it could not be incorporated as a standard of care in Pakistan, due to limited resources. Hence CHOP is still used extensively for treatment of DLBCL cases.
Rituximab however has not been investigated in Pakistani DLBCL population. Only one case report has been published in ALL (Acute Lymphoblastic Lymphoma) patient.⁷
The present study was designed and undertaken as a Randomized Control Trial to determine response and relapse rates in diffuse large B cell lymphoma (DLBCL) patients receiving rituximab, cyclophosphamide, adriamycin, vincristine and prednisolone (R-CHOP) versus cyclophosphamide, adriamycin, vincristine and prednisolone (CHOP) between April 2007 and December 2008 at the Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH & RC), Lahore, Pakistan.