Management of lymphoma in a centre with high HIV and tuberculosis prevalence

Date
2021-12
Journal Title
Journal ISSN
Volume Title
Publisher
Stellenbosch : Stellenbosch University
Abstract
Background The staging and management of patients with lymphoma (PWL) can be challenging and is particularly so in environments of high HIV and TB prevalence such as South Africa, for which there is little guidance. The additional contribution of positron emission tomography/computerised tomography (PET/CT) for assessing bone marrow involvement (BMI) in this setting is also uncertain. Methods This cross-sectional analytic study evaluated the clinical profiles, therapeutic interventions, including PET/CT scans, and outcomes of PWL at the Haematology unit, Tygerberg Hospital. We evaluated the potential utility of differential uptake of 18F- flouro deoxyglucose (FDG) on PET/CT in identifying second pathologies such as HIV and TB, in conjunction with clinical information and the use of additional testing, such a biopsy of discrepant uptake. The relative frequencies and causes of discrepancies of intensity of visual uptake of FDG, which the study termed the two-tone sign (2TS), was evaluated in both HIV- positive and HIV-negative patients. Results Two hundred and eighty patients, 101 HIV-positive and 178 HIV-negative, were recruited from a pool of 516 PWL, referred to the unit from March 2015 to March 2020. The median age of the patients was 42 years, with HIV-positive patients significantly younger than the HIV-negative cohort (p= 0.02). Significantly more HIV- positive patients had a history of TB or were on therapy for TB at presentation (p=<0.01). However, HIV-negative patients had significantly more other co- morbidities (p=<0.01). The 2 main subtypes of lymphoma were diffuse large B-cell lymphoma (DLBCL) and Hodgkin lymphoma (HL), with DLBCL being commoner in HIV-positive and HL in HIV- negative patients. Seventy-six percent of patients presented with advanced disease, similar in HIV-positive and HIV-negative patients (75.2 vs.76.4%). Complete remission rate was significantly better in HIV-negative patients with DLBCL while, with HL, there was no significant difference in outcomes between HIV- positive and HIV-negative patients. The 2TS was found with a higher frequency in the HIV-positive group than HIV- negative group (39.5% vs 25.3%), with a trend towards statistical significance (p=0.056). Causes of a 2TS were HIV, TB, lymphoma, synchronous malignancies or reactive uptake. In most patients, the cause of the discrepancy was identifiable and disease burden and response to therapy could be assessed. With respect to bone marrow involvement with lymphoma, congruence was demonstrated between the bone marrow biopsy (BMB) and PET/CT in 63.2% of patients with no significant difference between HIV positive and negative patients. The overall sensitivity of PET/CT was 87% (CI: 77.4-93.6%) and specificity 75.2% (CI: 66.7-82.5%). There was no impact of HIV on the BMB patterns on PET/CT, despite there being HIV-associated changes on the BMB in some patients. None of the patients evaluated, had TB on the BMB. Incongruence between BMB and PET/CT was found in 17 HIV negative patients with HL, with diffuse bone marrow uptake on PET/CT and a negative BMB. Conclusions This study demonstrated the complexities of patients with lymphoma managed at the unit, both HIV-positive and HIV-negative. Despite the aggressive rollout of antiretroviral therapy, many HIV-positive patients were not virologically controlled and presented with advanced, aggressive subtypes of lymphoma. The study found that it is possible to stage HIV-positive patients and those with TB using PET/CT, provided this is done with all available clinical information. We propose that in patients with HL and in most patients with DLBCL in our setting, both HIV-positive and HIV-negative, BMB is not required for assessment of BMI.
AFRIKAANSE OPSOMMING: Geen opsomming beskikbaar
Description
Thesis (PhD)--Stellenbosch University, 2021.
Keywords
Tuberculosis, UCTD, Lymphoma -- Patients -- Management, HIV-positive persons
Citation