Allogeneic transplantation for multiple myeloma: late relapse may occur as localised lytic lesion/plasmacytoma despite ongoing molecular remission

Dose evaluation indices for total body irradiation using TomoDirect with different numbers of ports: A comparison with the TomoHelical method

TomoDirect has been reported to have some advantages over TomoHelical in delivering total body irradiation (TBI). This study aimed to investigate the relationships between the number of ports and the dose evaluation indices in low‐dose TBI in TomoDirect mode using 2–12 ports and to compare these data with those for the TomoHelical mode in a simulation study. Thirteen patients underwent low‐dose TBI in TomoHelical mode from June 2015 to June 2016. We used the same computed tomography data sets for these patients to create new treatment plans for upper‐body parts using TomoDirect mode with 2–12 beam angles as well as TomoHelical mode. The prescription was 4 Gy in two equal fractions. For the TomoDirect data, we generated plans with 2–12 ports with approximately equally spaced angles; the modulation factor, field width, and pitch were 2.0, 5.0 cm, and 0.500, respectively. For the TomoHelical plans, the modulation factor, field width, and pitch were 2.0, 5.0 cm, and 0.397, respectively. D2, D98, D50, and the homogeneity index (HI) were evaluated to compare TomoDirect plans having 2–12 ports with the TomoHelical plan. Using TomoDirect plans, D2 with four ports or fewer, D98 with 10 ports or fewer, D50 with four ports or fewer and HI with five ports or fewer showed statistically significantly worse results than the TomoHelical plan. With the TomoDirect plans, D2 with seven ports or more, D50 with eight ports or more, and HI with eight ports or more showed statistically significant improvement compared with the TomoHelical plan. All of the dose evaluation indices of the TomoDirect plans showed a tendency to improve as the number of ports increased. TomoDirect plans showed statistically significant improvement of D2, D50, and HI compared with the TomoHelical plan. Therefore, we conclude that TomoDirect can provide better dose distribution in low‐dose TBI with TomoTherapy.

Long-term follow up of tandem autologous-allogeneic hematopoietic cell transplantation for multiple myeloma

We previously reported initial results in 102 multiple myeloma (MM) patients treated with sequential high-dose melphalan and autologous hematopoietic cell transplantation followed by 200 cGy total body irradiation with or without fludarabine 90 mg/m² and allogeneic hematopoietic cell transplantation. Here we present long-term clinical outcomes among the 102 initial patients and among 142 additional patients, with a median follow up of 8.3 (range 1.0-18.1) years. Donors included human leukocyte antigen identical siblings (n=179) and HLA-matched unrelated donors (n=65). A total of 209 patients (86%) received tandem autologous-allogeneic upfront, while thirty-five patients (14%) had failed a previous autologous hematopoietic cell transplantation before the planned autologous-allogeneic transplantation. Thirty-one patients received maintenance treatment at a median of 86 days (range, 61-150) after allogeneic transplantation. Five-year rates of overall survival (OS) and progression-free survival (PFS) were 54% and 31%, respectively. Ten-year OS and PFS were 41% and 19%, respectively. Overall non-relapse mortality was 2% at 100 days and 14% at five years. Patients with induction-refractory disease and those with high-risk biological features experienced shorter OS and PFS. A total of 152 patients experienced disease relapse and 117 of those received salvage treatment. Eighty-three of the 117 patients achieved a clinical response, and for those, the median duration of survival after relapse was 7.8 years. Moreover, a subset of patients who became negative for minimal residual disease (MRD) by flow cytometry experienced a significantly lower relapse rate as compared with MRD-positive patients (P=0.03). Our study showed that the graft-versus-myeloma effect after non-myeloablative allografting allowed long-term disease control in standard and high-risk patient subsets. Ultra-high-risk patients did not appear to benefit from tandem autologous/allogeneic hematopoietic cell transplantation because of early disease relapse. Incorporation of newer anti-MM agents into the initial induction treatments before tandem hematopoietic cell transplantation and during maintenance might improve outcomes of ultra-high-risk patients. Clinical trials included in this study are registered at: clinicaltrials.gov identifiers: 00075478, 00005799, 01251575, 00078858, 00105001, 00027820, 00089011, 00003196, 00006251, 00793572, 00054353, 00014235, 00003954.

Prognostic significance of tumor burden assessed by whole-body magnetic resonance imaging in multiple myeloma patients treated with allogeneic stem cell transplantation

Allogeneic stem cell transplantation is a therapeutic option under dispute but nonetheless chosen with increasing frequency for patients suffering from multiple myeloma in Europe. To study possible predictors of survival, 79 patients were investigated using whole-body magnetic resonance imaging to assess the visible tumor burden before and after allogeneic stem cell transplantation. Statistical analysis of clinical and imaging parameters included Cox regression models and distribution of survival time estimates (Kaplan-Meier method). Log rank test was used to determine the prognostic impact of the presence of focal lesions on survival. A higher tumor burden according to the lesion count was associated with a shorter overall survival (univariable/multivariable Cox regression: 1^st magnetic resonance imaging P=0.028/P=0.048; 2^nd magnetic resonance imaging P=0.008/P=0.024). Focal infiltration pattern itself seemed to be an additional adverse prognostic factor for overall survival (2^nd MRI P=0.048), although no definite cut-off could be defined. Kaplan-Meier estimates at 60 months of follow up show a significant difference (Log rank P=0.04) for overall survival rates between patients with focal infiltration (32%) and those without (75%). Since this subgroup of patients may benefit from maintenance therapy, adoptive immunotherapy, or local interventions, whole-body imaging is an appropriate and highly recommendable diagnostic approach for detection of prognostically relevant lesions before and after treatment.

Peripheral dose heterogeneity due to the thread effect in total marrow irradiation with helical tomotherapy

PURPOSE

To report potential dose heterogeneity leading to underdosing at different skeletal sites in total marrow irradiation (TMI) with helical tomotherapy due to the thread effect and provide possible solutions to reduce this effect.

METHODS AND MATERIALS

Nine cases were divided into 2 groups based on patient size, defined as maximum left-to-right arm distance (mLRD): small mLRD (≤47 cm) and large mLRD (>47 cm). TMI treatment planning was conducted by varying the pitch and modulation factor while a jaw size (5 cm) was kept fixed. Ripple amplitude, defined as the peak-to-trough dose relative to the average dose due to the thread effect, and the dose-volume histogram (DVH) parameters for 9 cases with various mLRD was analyzed in different skeletal regions at off-axis (eg, bones of the arm or femur), at the central axis (eg, vertebrae), and planning target volume (PTV), defined as the entire skeleton plus 1-cm margin.

RESULTS

Average ripple amplitude for a pitch of 0.430, known as one of the magic pitches that reduce thread effect, was 9.2% at 20 cm off-axis. No significant differences in DVH parameters of PTV, vertebrae, or femur were observed between small and large mLRD groups for a pitch of ≤0.287. Conversely, in the bones of the arm, average differences in the volume receiving 95% and 107% dose (V95 and V107, respectively) between large and small mLRD groups were 4.2% (P=.016) and 16% (P=.016), respectively. Strong correlations were found between mLRD and ripple amplitude (rs=.965), mLRD and V95 (rs=-.742), and mLRD and V107 (rs=.870) of bones of the arm.

CONCLUSIONS

Thread effect significantly influences DVH parameters in the bones of the arm for large mLRD patients. By implementing a favorable pitch value and adjusting arm position, peripheral dose heterogeneity could be reduced.

Recurrent plasmacytomas after allografting in a patient with multiple myeloma

Extramedullary recurrence in multiple myeloma patients has been reported after both autologous and allogeneic hematopoietic cell transplantation and, more recently, after treatment with so-called new drugs with potent antimyeloma activity. Only a very few sizable reports focused on its clinical presentation and its incidence, which may be highly underestimated, and most observations are based on single patients reported from several institutions. Given the unusual sites of recurrence, diagnosis may be rather difficult and delayed treatment may play a relevant role in prognosis. Here we report a case of a myeloma patient, initially treated with an allograft, who enjoyed an eleven-year disease-free remission with very good quality of life. She eventually relapsed first with an extramedullary plasmacytoma in the breast and, two years later, with a right atrial cardiac mass.

Durable responses after donor lymphocyte infusion for patients with residual multiple myeloma following non-myeloablative allogeneic stem cell transplant

The role of donor lymphocyte infusion (DLI) in mediating the graft-versus-myeloma (GvM) effect after allogeneic hematopoietic stem cell transplant (allo-HCT) is not clearly defined. We evaluated the safety and utility of DLI in patients with either persistent or recurrent multiple myeloma (MM) after allo-HCT. Twenty-three patients with MM received DLI after allo-HCT at the University of Texas M. D. Anderson Cancer Center between July 1996 and June 2008. Eight patients received preemptive DLI for residual disease (RD) while 15 patients received DLI for the treatment of recurrent or progressive disease (PD). We evaluated the response to DLI and the factors that may predict a response. Median DLI dose was 3.3 × 10(7) CD3 + cells (range 0.5-14.8 × 10(7)). Grade II-IV acute graft-versus-host disease (GvHD) was seen in five patients (22%). Median follow-up in surviving patients was 24 months. Five of 23 patients (22%) achieved a complete or a very good partial response (two CR, three VGPR), while eight patients (34%) had stable disease (SD) after the DLI. Patients who received DLI for RD had a higher response rate (≥ VGPR 50% vs. 7%, p = 0.03), a longer overall survival (28.3 vs. 7.6 months, p = 0.03) and a trend toward longer progression-free survival (11.9 vs. 5.2 months, p = 0.1). In this largest single institution study, we conclude that the use of preemptive, non-manipulated DLI for RD after reduced-intensity conditioning allo-HCT is encouraging, and it was associated with a higher response rate and a longer overall survival when given preemptively. The role of DLI needs to be further explored in prospective clinical trials.

NCI First International Workshop on the Biology, Prevention, and Treatment of Relapse after Allogeneic Hematopoietic Stem Cell Transplantation: Report from the Committee on Treatment of Relapse after Allogeneic Hematopoietic Stem Cell Transplantation

Relapse is a major cause of treatment failure after allogeneic hematopoietic stem cell transplantation (alloHSCT). Treatment options for relapse have been inadequate, and the majority of patients ultimately die of their disease. There is no standard approach to treating relapse after alloHSCT. Withdrawal of immune suppression and donor lymphocyte infusions are commonly used for all diseases; although these interventions are remarkably effective for relapsed chronic myelogenous leukemia, they have limited efficacy in other hematologic malignancies. Conventional and novel chemotherapy, monoclonal antibody therapy, targeted therapies, and second transplants have been utilized in a variety of relapsed diseases, but reports on these therapies are generally anecdotal and retrospective. As such, there is an immediate need for well-designed, disease-specific trials for treatment of relapse after alloHSCT. This report summarizes current treatment options under investigation for relapse after alloHSCT in a disease-specific manner. In addition, recommendations are provided for specific areas of research necessary in the treatment of relapse after alloHSCT.

Late relapse of a light-chain myeloma as extramedullary plasmacytoma of the thyroid gland after second allogeneic stem-cell transplantation

We present a rare experience with a myeloma patient who had a late relapse as isolated extramedullary plasmacytoma of the thyroid gland after a second allogeneic transplantation. We give PET/CT scan findings at diagnosis and during follow up of the disease after subsequent management. The possible pathogenesis of the late extramedullary relapse of myeloma after allogeneic stem-cell transplantation and management options are discussed.

Incidence, presenting features and outcome of extramedullary disease in multiple myeloma: a longitudinal study on 1003 consecutive patients

BACKGROUND

There are few data on the incidence and prognosis of extramedullary (EM) multiple myeloma (MM). There are concerns about a possible increase of EM relapses with the expanding use of high-dose therapy (HDT) and biological agents.

PATIENTS AND METHODS

The incidence of EM disease, its relationship with prior exposure to HDT or novel agents, and its prognostic impact were analyzed in 1003 MM patients. Based on the different therapies available, three periods were considered: 1971-1993, conventional-dose chemotherapy; 1994-1999, HDT for younger patients; and 2000-2007, introduction of novel agents.

RESULTS

Overall, 13% of patients had EM disease, 7% at diagnosis and 6% later. In the 2000-2007 period, there was a significant increase of EM involvement, at diagnosis (P = 0.02) and during follow-up (P = 0.03). The risk of EM spread was not significantly increased after HDT [hazard ratio (HR 0.6)], bortezomib (HR 1.62), or thalidomide/lenalidomide (HR 1.07). EM disease was associated with shorter overall (HR 3.26, P < 0.0001) and progression-free (HR 1.46, P = 0.04) survival.

CONCLUSIONS

The incidence of EM disease has increased, probably due to the availability of more sensitive imaging techniques and the prolongation of patients' survival. HDT or novel agents seem not to increase the risk of EM disease. EM involvement confers a poor prognosis.

Long-term outcome of myeloablative allogeneic stem cell transplantation for multiple myeloma

Allogeneic stem cell transplantation (alloSCT) has been used in the hopes of harnessing the curative potential of the graft-versus-myeloma effect. This study examines the long-term outcomes of a large cohort of patients with myeloma who were treated with myeloablative alloSCT at a single center. Comparisons are made with those who were treated with autologous stem cell transplantation (ASCT). Between January 1989 and February 2002, 158 patients age<or=55 years underwent SCT for myeloma. Seventy-two patients underwent myeloablative alloSCT (58 related; 14 unrelated), whereas 86 patients underwent ASCT. Most patients received single-agent high dose dexamethasone or VAD (vincristine, adriamycin, dexamethasone) therapy pre-SCT. Conditioning regimens were melphalan-based for all ASCT patients, whereas the alloSCT patients received melphalan-based (70%), total-body irradiation (TBI)-based (18%), or other (13%). Patients who underwent alloSCT were younger, had a higher Durie-Salmon stage disease, and a shorter median time from diagnosis to transplant. Myeloma subtypes were similar between groups. Other pre-SCT (BMT) characteristics were similar except that ASCT patients had a higher proportion of cases that received palliative radiotherapy pre-SCT. Disease response pre-SCT was similar. At last follow-up, 61 of 158 patients are alive with a median follow-up of 88.4 months (range: 35.5-208.5). The overall survival (OS) of the alloSCT cohort was 48.1% at 5 years and 39.9% at 10 years compared to 46.2% at 5 years and 30.8% at 10 years for the ASCT cohort (P=.94). The event-free survival of the alloSCT cohort was 33.3% at 5 years and 31.4% at 10 years compared to 32.9% and 15.2%for the ASCT cohort (P=.64). Treatment-related mortality (TRM) at 1 year was 22% for the alloSCT cohort and 14% in the ASCT cohort (P=.21). Cumulative incidence of grade II-IV acute graft-versus-host disease (aGVHD) was 72% and the cumulative incidence of chronic GVHD (cGVHD) was 68% at 2 years. Neither aGVHD nor cGVHD had an influence on OS or event-free survival, although 5 of 14 patients who have received donor lymphocyte infusions (DLI) have had disease response. The risk of relapse was reduced in those who developed aGVHD (P=.02) but not cGVHD (P=.23). In conclusion, although there are patient who are alive without disease>10 years post myeloablative alloSCT, similarly there are long-term survivors post-ASCT. Myeloablative alloSCT should not be considered standard treatment, and should only be considered in the context of a clinical trial.

Primary plasma cell leukemia: morphologic, immunophenotypic, and cytogenetic features of 4 cases treated with chemotherapy and stem cell transplantation

Plasma cell leukemia (PCL) is a neoplastic disorder of plasma cells of which there are 2 forms, primary PCL and secondary PCL, the latter occurring in patients with a history of plasma cell myeloma. We describe 4 patients with primary PCL. In all cases, the bone marrow aspirate smears and biopsy specimens demonstrated a diffuse infiltrate of atypical plasma cells that were difficult to classify using morphologic criteria alone. Immunophenotypic studies showed that each case was positive for plasma cell-associated antigens (cytoplasmic immunoglobin, CD38, or CD138) and negative for CD20. Of 4 cases, 3 had complex karyotypes, including the t(11;14)(q13;q32) or del(11)(q13). Despite chemotherapy and the use of novel therapeutic agents and stem cell transplantation, all 4 patients had short survival.

Plasmacytoma relapses in the absence of systemic progression post-high-dose therapy for multiple myeloma

Autologous (ASCT) and allogeneic stem cell transplantations (alloBMT) are well-established therapies for multiple myeloma. However, patients continue to relapse at a constant rate. We present here 15 out of 163 patients who underwent SCT and relapsed with plasmacytomas only without evidence of bone marrow disease progression (14/147 post-ASCT and 1/16 post-alloBMT). The median time from SCT to plasmacytoma relapse was 24 months. The sites of plasmacytoma included bone, skin, rectum, and testicles. Five patients were treated with local radiotherapy, while seven patients received a combination of radiotherapy and chemotherapy or thalidomide, and two patients received chemotherapy alone with or without thalidomide. The recipient of alloBMT was initially treated with VAD-chemotherapy and local radiotherapy followed by a mini-allograft from the original donor. Eleven patients died at a median of 10 months following diagnosis of the plasmacytoma. Four are still alive, 12-20 months post-plasmacytoma diagnosis. These cases of unconventional disease recurrence are likely to be seen due to sub-clinical seeding of tumour cells suggestive of the presence of an extramedullary (EM) clone of plasma cells with a high degree of chemoresistance. We also review all the available data in the literature for the optimal therapy for patients with isolated EM relapse.

The outcome of unrelated donor stem cell transplantation for patients with multiple myeloma

We performed a retrospective analysis of outcome in 45 patients with multiple myeloma receiving unrelated donor stem cell transplants (UD-SCT) in the UK between 1993 and 2002; 17 received myeloablative conditioning regimens and 28 received reduced intensity conditioning (RIC) protocols. Forty patients received pretransplant CAMPATH serotherapy. Forty-two of 45 patients had detectable disease at transplant, but 33 of 45 were chemoresponsive. Sixty per cent of patients had received a previous autograft. Myeloid engraftment was seen in 95% of recipients and was significantly faster in recipients receiving peripheral blood stem cells (P = 0.07) and RIC (P = 0.001). The incidence of severe (grade 3/4) acute graft versus host disease (aGvHD) was 5% (2/40). The 100-d non-relapse mortality was 18% (5/38) following RIC and 53% (9/17) following myeloablative regimens. Twenty-nine per cent of patients achieved a complete remission, 61% a partial remission, giving a 90% overall response rate. At median follow-up (513 d), overall survival was 40%: 54% in the RIC group (median follow-up: 489 d) and 18% in the myeloablative group (median follow-up: 560 d). In recipients of UD-SCT, RIC protocols that incorporated CAMPATH were associated with faster myeloid engraftment, less severe aGvHD and lower 100-d non-relapse mortality than myeloablative regimens, without a corresponding rise in relapse rate during the period of observation.