Absence of spontaneous response improvement beyond day +100 after autologous stem cell transplantation in multiple myeloma.

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.

Allogeneic hematopoietic SCT in multiple myeloma: long-term results from a single institution.

The role of allogeneic hematopoietic SCT (allo-HCT) in multiple myeloma (MM) remains controversial. A total of 58 patients received an allo-HCT (25 of them with myeloablative conditioning-allo-MAC-and 33 with reduced-intensity conditioning-allo-RIC) at our institution over a 28-year period. The CR rate for allo-MAC was 36%. The incidence of grade III-IV acute GVHD (aGVHD) and chronic GVHD (cGVHD) was 28% and 39%, respectively The TRM at any time was 60% and the main causes of death were aGVHD or infectious complications not directly related to GVHD. The estimated PFS and OS at 15 years were 8% and 15%, respectively. The CR rate with allo-RIC was 45%. The incidence of grade III-IV aGVHD and cGVHD were 24% and 41%, respectively. The TRM at any time was 33% and was mainly related to aGVHD. The estimated PFS and OS at 5 years were 22% and 38%, respectively. Despite its high TRM, a proportion of patients with high-risk myeloma (early relapse and newly diagnosed ultrahigh risk) may obtain long-term disease control with allo-HCT. New approaches aimed at decreasing the incidence of aGVHD, and consequently to decrease the TRM, are needed.

Transmissible cytotoxicity of multiple myeloma cells by cord blood-derived NK cells is mediated by vesicle trafficking.

Natural killer cells (NK) are important effectors of anti-tumor immunity, activated either by the downregulation of HLA-I molecules on tumor cells and/or the interaction of NK-activating receptors with ligands that are overexpressed on target cells upon tumor transformation (including NKG2D and NKP30). NK kill target cells by the vesicular delivery of cytolytic molecules such as Granzyme-B and Granulysin activating different cell death pathways, which can be Caspase-3 dependent or Caspase-3 independent. Multiple myeloma (MM) remains an incurable neoplastic plasma-cell disorder. However, we previously reported the encouraging observation that cord blood-derived NK (CB-NK), a new source of NK, showed anti-tumor activity in an in vivo murine model of MM and confirmed a correlation between high levels of NKG2D expression by MM cells and increased efficacy of CB-NK in reducing tumor burden. We aimed to characterize the mechanism of CB-NK-mediated cytotoxicity against MM cells. We show a Caspase-3- and Granzyme-B-independent cell death, and we reveal a mechanism of transmissible cell death between cells, which involves lipid-protein vesicle transfer from CB-NK to MM cells. These vesicles are secondarily transferred from recipient MM cells to neighboring MM cells amplifying the initial CB-NK cytotoxicity achieved. This indirect cytotoxicity involves the transfer of NKG2D and NKP30 and leads to lysosomal cell death and decreased levels of reactive oxygen species in MM cells. These findings suggest a novel and unique mechanism of CB-NK cytotoxicity against MM cells and highlight the importance of lipids and lipid transfer in this process. Further, these data provide a rationale for the development of CB-NK-based cellular therapies in the treatment of MM.

Pattern of relapse and progression after autologous SCT as upfront treatment for multiple myeloma.

The achievement of CR is the crucial step for a prolonged PFS and OS after an autologous SCT in multiple myeloma (MM). Unfortunately, even with the use of new regimens and the current high CR rates, most, if not all, patients will ultimately relapse or progress. We analyzed the type of relapse or progression (asymptomatic vs symptomatic), clinical features including the presence of extramedullary involvement and time to next treatment in 211 patients who underwent melphalan-based autologous SCT over an 18-year period at our institution. After autologous SCT, serological or asymptomatic relapse/progression was observed in about one half of the patients. The treatment-free interval was significantly longer in patients relapsing from CR than in those progressing from PR (P=0.017). Patients with serological relapse/progression had a significantly longer OS than those relapsing from symptomatic disease (P=0.002). The relapse pattern was similar to the initial clinical presentation. Survival after relapse/progression was shorter in those patients with a 24-h urine M-protein excretion of at least 200 mg (P=0.048). Extramedullary involvement was frequent (24%), being the highest risk in patients with extramedullary involvement at diagnosis (P=0.001).

Plasma cell leukemia: consensus statement on diagnostic requirements, response criteria and treatment recommendations by the International Myeloma Working Group.

Plasma cell leukemia (PCL) is a rare and aggressive variant of myeloma characterized by the presence of circulating plasma cells. It is classified as either primary PCL occurring at diagnosis or as secondary PCL in patients with relapsed/refractory myeloma. Primary PCL is a distinct clinic-pathological entity with different cytogenetic and molecular findings. The clinical course is aggressive with short remissions and survival duration. The diagnosis is based upon the percentage (≥ 20%) and absolute number (≥ 2 × 10(9)/l) of plasma cells in the peripheral blood. It is proposed that the thresholds for diagnosis be re-examined and consensus recommendations are made for diagnosis, as well as, response and progression criteria. Induction therapy needs to begin promptly and have high clinical activity leading to rapid disease control in an effort to minimize the risk of early death. Intensive chemotherapy regimens and bortezomib-based regimens are recommended followed by high-dose therapy with autologous stem cell transplantation if feasible. Allogeneic transplantation can be considered in younger patients. Prospective multicenter studies are required to provide revised definitions and better understanding of the pathogenesis of PCL.

Multiple myeloma.

Multiple myeloma (MM) constitutes 1% of malignant diseases and 15% of haematological malignancies. In virtually all patients MM is preceded by monoclonal gammopathy of undetermined significance (MGUS). The cause of monoclonal gammopathies and the mechanisms of progression are unknown. The diagnosis of MM requires the presence of an M-protein in serum and/or urine, increased bone marrow plasma cells and related organ or tissue impairment. Cytogenetic status, serum ß2-microglobulin and response to therapy are the key prognostic factors. The treatment of younger patients with MM should include a triple-agent induction regimen (i.e. bortezomib/thalidomide/dexamethasone), autologous stem cell transplantation (ASCT) and consolidation and maintenance incorporating novel agents along with sequential minimal residual disease studies to determine for how long treatment is still of benefit. Allogeneic transplantation with reduced-intensity conditioning is promising but remains experimental. For patients not eligible for ASCT the best initial regimens are melphalan/prednisone/thalidomide (MPT), melphalan/prednisone/bortezomib (MPV) and lenalidomide/dexamethasone. In relapsing patients, the choice of salvage therapy should depend on: (i) the components of initial therapy, (ii) the degree and duration of response, (iii) type of relapse: aggressive versus indolent, (iv) previous toxicities and (v) age and performance status. A sequential approach is preferred over combination of multiple agents. Supportive measures include the use of bisphosphonates and erythropoietin according to the updated guidelines.

Engraftment syndrome after auto-SCT: analysis of diagnostic criteria and risk factors in a large series from a single center.

Engraftment syndrome (ES) is increasingly observed in patients who receive auto-SCT. To investigate this fact, validate the clinical criteria for ES diagnosis and analyze the risk factors for this complication, we reviewed 328 consecutive peripheral blood auto-SCT performed during the past 7 years. A total of 43 patients presented with clinical or biological data suggestive of ES. Of the total, 41 (95%) and 22 (51%) could be diagnosed with ES using the Maiolino criteria (MC) and the Spitzer criteria (SC), respectively. The SC were less sensitive as they do not consider some relevant clinical data and limit the observation time after engraftment. All ES cases had high C-reactive protein (CRP) values not observed in the remaining patients at engraftment (median +/- s.d.: 17.5 +/- 7.3 vs 2.4 +/- 3.4 mg per 100 ml; P=0.0001). Multivariate analysis showed a higher risk of ES in SCT performed in recent years (relative risk (RR) 2.3, 95% confidence interval (CI 1.0-4.7), female patients (RR 2.5, 95% CI 1.2-5.2), and absence of intensive chemotherapy before SCT (RR 8.8, 95% CI 3.3-20.5). All patients except one improved after treatment with corticosteroids. The MC seem to be the best tool to establish a diagnosis of ES. In doubtful cases, the diagnosis could be confirmed by evaluating CRP. Auto-SCT in patients not receiving previous chemotherapy could explain the increasing incidence of ES in the past years.

Salvage chemotherapy with alternating MINE-ESHAP regimen in relapsed or refractory Hodgkin's lymphoma followed by autologous stem-cell transplantation.

BACKGROUND: High-dose chemotherapy (HDT) followed by autologous stem-cell transplantation (ASCT) is considered the gold standard in the treatment of patients with relapsed or refractory Hodgkin's lymphoma (HL). However, the optimal salvage regimen has not yet been established. PATIENTS AND METHODS: We retrospectively analyzed the efficacy and toxicity of MINE (mesna, ifosfamide, mitoxantrone, and etoposide) alternated with ESHAP (etoposide, methylprednisolone, high-dose cytarabine, and cisplatin) in the treatment of 61 relapsed or refractory HL patients after ABVD-based chemotherapy. RESULTS: Overall, 25 patients (41%) achieved a complete response (CR), 23 (38%) a partial response (PR), 4 (7%) a stable disease, and 8 (13%) progressed for an overall response rate of 79%. Response to first-line chemotherapy was the most important prognostic factor for response to MINE-ESHAP (P = 0.041). No grade 4 extrahematologic toxic effects or toxic deaths were observed. Adequate peripheral blood stem-cell collection was achieved in 56 of 59 (95%) mobilized patients. Overall survival and event-free survival after HDT and ASCT were significantly higher for patients achieving CR/PR in comparison with those refractory to MINE-ESHAP (46% and 35% versus 74% and 69%, respectively). CONCLUSION: MINE-ESHAP results in a high response rate with acceptable toxicity in patients with HL having failed ABVD-based treatment.

Study of the antibody response against Mycobacterium tuberculosis antigens in Warao Amerindian children in Venezuela.

This study was aimed at investigating alternate methods for serodiagnosis of tuberculosis (TB), which are needed because bacteriologic diagnosis of childhood TB is difficult. A selection of 80 serum and saliva samples were tested from Warao indigenous children under 15 years of age; 34 high TB suspects (28 positive and 6 negative for the tuberculin skin test, TST) and 46 healthy contact children (32 positive and 14 negative for the TST). Several enzyme-linked immunosorbent assay (ELISA) serological tests were developed to test for Mycobacterium tuberculosis-specific antibodies, including serum IgA, IgG, IgE, and secretory IgA (sIgA) in saliva against 3 specific antigens (PPD, HSP60, 38 kDa). Of these, 2 antigens, PPD and 38 kDa, showed significantly higher reactivity. The sensitivity and specificity of these tests for diagnosis remained limited, between 26.5% and 38.2%, and 77.4% and 97%, respectively. Of all the samples studied and combinations realized between all isotypes and antigens combined with 3 isotypes (anti-PPD IgG, IgE, and anti-38kDa sIgA) managed to detect the largest number of patients, showing an improved sensitivity level of 64.7%, although specificity levels dropped to 81.8%. These results were compared with the Omega diagnostics commercial kit results. The commercial kits showed significantly lower reactivity (sensitivity of 20% and 13.33% to Myco G and Complex Plus, respectively) and a specificity of 100%. This study shows that in indigenous populations of Venezuela, where invasive procedures cannot be used to select samples but evaluation with a chest X-ray for radiological studies is available, the combination of 3 specific isotypes may be a useful tool to increase diagnostic accuracy with pulmonary TB in this population, when used together with clinical and epidemiological criteria.

Study of the antibody response against Mycobacterium tuberculosis antigens in Warao Amerindian children in Venezuela

This study was aimed at investigating alternate methods for serodiagnosis of tuberculosis (TB), which are needed because bacteriologic diagnosis of childhood TB is difficult. A selection of 80 serum and saliva samples were tested from Warao indigenous children under 15 years of age; 34 high TB suspects (28 positive and 6 negative for the tuberculin skin test, TST) and 46 healthy contact children (32 positive and 14 negative for the TST). Several enzyme-linked immunosorbent assay (ELISA) serological tests were developed to test for Mycobacterium tuberculosis-specific antibodies, including serum IgA, IgG, IgE, and secretory IgA (sIgA) in saliva against 3 specific antigens (PPD, HSP60, 38 kDa). Of these, 2 antigens, PPD and 38 kDa, showed significantly higher reactivity. The sensitivity and specificity of these tests for diagnosis remained limited, between 26.5 percent and 38.2 percent, and 77.4 percent and 97 percent, respectively. Of all the samples studied and combinations realized between all isotypes and antigens combined with 3 isotypes (anti-PPD IgG, IgE, and anti-38kDa sIgA) managed to detect the largest number of patients, showing an improved sensitivity level of 64.7 percent, although specificity levels dropped to 81.8 percent. These results were compared with the Omega diagnostics commercial kit results. The commercial kits showed significantly lower reactivity (sensitivity of 20 percent and 13.33 percent to Myco G and Complex Plus, respectively) and a specificity of 100 percent. This study shows that in indigenous populations of Venezuela, where invasive procedures cannot be used to select samples but evaluation with a chest X-ray for radiological studies is available, the combination of 3 specific isotypes may be a useful tool to increase diagnostic accuracy with pulmonary TB in this population, when used together with clinical and epidemiological criteria.