Autologous Bone Marrow Transplantation - Blog Science Connections

Proposed International Adult Lymphoma Study 321
disease and RR, response rates are nearly identical with and without TBI (68%
compared with 72%). Also, 75% of the relapses were isolated and occurred
primarily at the site of initial lymphoma involvement prior to the salvage
therapy, indicating that local control is a major factor. Involved-field
radiotherapy (15-20 Qy) has been advocated by Phillips et a/. (37,38),
following a nonrandomized comparative study favoring this strategy. This
question will be considered in our randomized study (see below).
In this series, patients with marrow involvement were excluded, and
marrow relapses were not a major problem following ABMT. It is impossible
to distinguish relapse owed to failure to eradicate the tumor from relapse
owed to reinfused tumor cells. However, experience with allogeneic bone
marrow transplantation (BMT) suggests that failure of the preparative
regimen is responsible for most relapses (39-43). Encouraging results have
been reported with marrow purging in adult patients with B-cell non-
Hodgkin's lymphoma (44,45), and we would advocate that this issue be
evaluated in a future comparative study. (If regimens without TBI are used, it
is possible that spontaneous marrow recovery could occur; therefore,
intensification therapy without ABMT is also a possible alternative.) However,
in this first international collaborative study, no attempt will be made to purge
marrow prior to ABMT.
In summary, our group's background work confirms that patients who
did not achieve CR on first-line therapy are rarely curable with current highdose
therapy regimens. In patients who relapse after a first CR, a significant
cure rate can be achieved. Patients still responding to conventional doses of
chemotherapy have an outcome superior to that of patients whose tumors are
resistant to rescue protocols (38% compared with 14% 2-year disease-free
survival). Despite strong suggestions from the literature that high-dose
therapy with ABMT is superior to conventional modalities of treatment for
relapsed non-Hodgkin's lymphoma, a randomized study to clearly determine
whether ABMT adds to survival in a group of potentially curable patients is
needed because of the various selection criteria that until now clearly favored
the ABMT patients. The conclusions of these studies are the following:
1. Massive therapy and ABMT should not be tested in a randomized study of
patients who never reach CR (Fig 8).
2. All patients whose disease has a diffuse histology, either intermediate or
high grade, at first diagnosis are eligible (cases of transformation from
nodular histology are excluded).
3. With the exclusion from the study of patients who never reach a CR in the
course of their disease, the group in SR is the most suitable for comparing
chemotherapy alone with the ABMT strategy.
4. Purging marrow is not a major issue for this group of patients. The study
will concern only selected patients with normal marrow, and no purging
procedures will be allowed in the ABMT arm of the study.