Absence of spontaneous response improvement beyond day +100 after autologous stem cell transplantation in multiple myeloma
Fernández de Larrea C (1), Dávila J (2), Isola I (1), Ocio EM (2), Rosiñol L (1), García-Sanz R (2), Cibeira MT (1), Tovar N (1), Rovira M (1), Mateos MV (2), Miguel JS (3), Bladé J (1).
The response evaluation after autologous stem-cell transplantation (ASCT) is usually performed at day +100 in patients with multiple myeloma (MM). A recent report suggests that improvement in the response can be observed beyond day +100.
The aim of the present study has been to evaluate the rate of improved response and outcome beyond day +100 after ASCT, with and without maintenance therapy. One hundred and forty-four patients who underwent single ASCT with chemosensitive disease and achieved less than CR at day 100 post ASCT were evaluated.
Seventy-four patients (51.4%) did not receive any maintenance with only one of them showing an upgrade in the response. The remaining 70 patients (48.6%) received maintenance therapy; eleven of them (15.7%) improved their response beyond day +100.
The outcome of these patients was better than those who did not upgrade their response in both progression-free survival and overall survival (P=0.019 and P=0.031, respectively).
In conclusion, the improvement in response beyond day +100 after ASCT in patients not receiving any therapy is exceedingly rare. A minority of patients receiving maintenance therapy after ASCT upgrades their response and this finding is associated with better outcome.