Peripheral Blood Stem-Cell Mobilisation and Autologous Stem Cell Transplantation In HIV-Related Malignancies.

Patients (pts) with HIV-infection are generally excluded from clinical trials that evaluate the role of high dose chemotherapy (HDCT) in malignant lymphoma or relapsed germ cell tumor (GCT). However, recent data indicate that HDCT followed by autologous peripheral blood stem cell transplantation (ASCT) may be effective in relapsed HIV-related lymphoma.

This is an observational cohort study including patients with HIV-related lymphoma or HIV-related GCT who have peripheral blood stem cells mobilized by a combination of chemotherapy (CT) and G-CSF. Pts did or did not undergo consecutive ASCT. The primary outcome measure is feasibility. High-dose BEAM was used as a conditioning regimen in pts with HIV-related lymphoma while high-dose carboplatin/etoposide (CE) was chosen for pts with GCT.

From 07/05 to 03/10 peripheral blood stem cells (PBSC) were successfully harvested in 10 of 11 HIV-infected pts with diffuse large B-cell lymphoma (DLBCL) [n=4], Burkitt's lymphoma (BL) [n=3], plasmablastic lymphoma (PL) [n=2], Hodgkin lymphoma (HL) [n=1] and testicular GCT [n=1]. The mean number of collected stem cells was 15.7×10⁶/kg CD34+ cells (range, 6.3 – 33). PBSC-mobilisation failed in one pt with relapsed BL. 7 of 11 pts were mobilized following salvage CT for DLBCL [n=4], BL [n=1], HL [n=1] or GCT [n=1] while 4 pts were under primary CT for BL or PL. So far, 5 of 10 pts received HDCT + ASCT. Pt 1 (44 yrs, CDC C3; HIV-RNA< 50 cop/ml at time of SCT) received HDCT as 3^rd salvage therapy for DLBCL. A total of 9.2 × 10⁶/kg CD34+ cells were transplanted. Neutrophil engraftment occurred on day +14. The pt achieved a partial remission but died of progressive lymphoma 6 months after ASCT. Pt 2 (60 yrs, CDC B3; HIV-RNA< 50/ml) underwent HDCT + ASCT (13.8 × 10⁶/kg CD34+ cells) for a 1^st relapse of HL. Neutrophil engraftment was observed on day +10. The pt is well and disease free 25 months after ASCT. Pt 3 (26 yrs, CDC C3, HIV-RNA< 50/ml), a hepatitis C co-infected haemophiliac, received HDCT + ASCT for refractory DLBCL but died of liver cirrhosis and neutropenic sepsis with multi-organ failure on day +16. Pt 4 (25 yrs, CDC A3, HIV-RNA< 50/ml) received 3 sequential courses of HD-CE followed by ASCT in 3-week intervals for a 3^rd relapse of a nonseminomatous GCT. Neutrophil engraftment occurred on day +10, + 12 and +14, respectively. A complete remission (CR) was achieved. However, the pt suffered another relapse involving the central nervous system and died of progressive GCT 15 month after the 3^rd transplant. Pt 5 (41 yrs, CDC C3, HIV-RNA 220/ml) underwent HDCT in 2^nd complete remission after successful salvage-CT for a first sensitive relapse of DLBCL. A total of 12.9 × 10⁶/kg CD34+ cells were transplanted. The pt is currently alive and neutropenic (day +3). ASCT was not performed in the other 6 pts because of refractory BL [n=1], ongoing first remission following induction CT for BL [n=2] and PL [n=2] and concomitant histoplasmosis necessitating antifungal therapy [n=1].

Successful mobilisation of PBSC is feasible in the majority of pts with HIV-related malignancies. ASCT seems effective in selected pts with chemo-sensitive relapse of malignant lymphoma or GCT. HIV-infected pts should no longer be excluded from HDCT-programs.

No relevant conflicts of interest to declare.