Subtypes and Treatment Outcomes of Adolescent and Adult Non-Hodgkins Lymphoma in a Resource Poor Setting

Introduction: Non- Hodgkins lymphomas (NHL) are a heterogeneous group of clonal malignant diseases arising from the lymphoid system with many subtypes showing both biological and clinical heterogeneity. However, the diagnosis and treatment outcomes of NHL in resource poor countries still remain a challenge in the absence of routine immunohistochemistry and molecular studies. In Ghana, a low middle-income West African country, there has been no previous systematic study of the distribution of the major subtypes of NHL.

Methods: A retrospective review of case folders of all patients age 13 years and above, diagnosed with NHL between January 1, 2008 and October 31, 2013, at Korle Bu Teaching Hospital (KBTH), Accra, the largest hospital in Ghana, and one of only two hospitals in the country with a cancer unit. Information obtained from the case folders included age, sex, histological subtype, subtypes using the Working Formulation and WHO classifications. Treatment given and follow up information were also evaluated.

Results: A total of 279 cases of NHL were identified within the study period. The mean overall age of the patients was 48.8 ± 17.0 years with a minimum age of 13 years and maximum 87 years. There were 156 males (55.7 %) and 123 females (43.9 %) with a male to female ratio of approximately 1.5:1. The majority of cases seen (53%) were diffuse large B-cell lymphoma. Chronic lymphocytic leukaemia/small lymphocytic lymphoma (22.2%) was the next commonest subtype. Other sub types seen, in order of frequency, included diffuse mixed cell lymphoma (6.4%), gastric lymphomas (3.9%), mediastinal B-cell lymphoma (2.9%), Burkitts lymphoma (1.8%), splenic marginal zone B-cell lymphoma (1.1%), lymphoblastic lymphoma (1.1%), mucosa-associated lymphoid tissue (MALT) type B- cell lymphoma (0.7%) and follicular lymphoma (0.7%). Others, which included anaplastic large cell lymphoma, mantle cell lymphoma, lymphoplasmacytic lymphoma and mycosis fungoides, collectively accounted for 3.6% of the NHL cases reviewed. Based on the Working Formulation classification with broad histologic categories of low-, intermediate-, and high-grade lymphomas, 83 out of 279 (29.7%) had low grade NHL, 170 (60.7%) intermediate and 26(9.4%) had aggressive/high grade NHL.

Table 1 shows chemotherapy regimens administered and first year treatment outcomes. One-year survival for cases of NHL in the study was found to be high (98.6%). However, only 115/279(41.2%) of patients were seen for follow up in the second year post-treatment, with 85 of these (73.9%) still in clinical remission. In the third year only 37/279(13.3%) reported for follow up.

Conclusions: This study provides a baseline overview of the distribution of NHL subtypes and their outcomes in adolescent and adult patients in a resource constrained setting. Patient loss to follow up in the 2^nd and 3^rd year post treatment was very high and the reasons for this should be explored in a future study. Immunohistochemistry, cytogenetics and specific molecular studies, which are important in characterization of NHL, should be made affordable and accessible in low-income countries.