Predictors of unsustained measurable residual disease negativity in patients with multiple myeloma

ABSTRACT

The prognostic impact of achieving and in particular maintaining measurable residual disease (MRD) negativity in multiple myeloma is now established; therefore, identifying among MRD-negative patients the ones at higher risk of losing MRD negativity is of importance. We analyzed predictors of unsustained MRD negativity in patients enrolled in the FORTE trial (NCT02203643). MRD was performed by multiparameter flow cytometry (sensitivity of 10-5) at premaintenance and every 6 months thereafter. The cumulative incidence (CI) of MRD resurgence and/or progression was analyzed in MRD-negative patients. A total of 306 of 474 (65%) MRD-negative patients were analyzed. After a median follow-up of 50.4 months from MRD negativity, 185 of 306 (60%) patients were still MRD negative and progression free, 118 (39%) lost their MRD-negative status, and 3 patients (1%) died without progression. Amp1q vs normal (4-year CI, 63% vs 34), ≥2 concomitant high-risk cytogenetic abnormalities vs 0 (4-year CI, 59% vs 33%), circulating tumor cells at baseline (high vs low at 4-year CI, 62% vs 32%), and time-to-reach MRD negativity postconsolidation vs preconsolidation (4-year CI, 46% vs 35%) were associated with a higher risk of unsustained MRD negativity in a multivariate Fine-Gray model. During the first 2 years of maintenance, patients receiving carfilzomib-lenalidomide vs lenalidomide alone had a lower risk of unsustained MRD negativity (4-year CI, 20% vs 33%).

Prospective evaluation of minimal residual disease in the phase II FORTE trial: a head-to-head comparison between multiparameter flow cytometry and next-generation sequencing

Background

Limited data are available on the concordance between multiparameter flow cytometry (MFC) and next-generation sequencing (NGS) for minimal residual disease (MRD) detection in a large trial for multiple myeloma (MM) patients.

Methods

MRD was explored in the FORTE trial for transplant-eligible MM patients randomised to three carfilzomib-based induction-intensification-consolidation treatments and carfilzomib-lenalidomide (KR) vs R maintenance. MRD was assessed by 8-colour 2nd-generation flow cytometry in patients with ≥very good partial response before maintenance. NGS was performed in case of suspected complete response (CR) in a correlative subanalysis. Biological/prognostic concordance between MFC and NGS, conversion to MRD negativity during maintenance, and 1-year/2-year sustained MRD negativity were explored.

Findings

Between September 28, 2015 and December 22, 2021, 2020 samples were available for MFC and 728 for the simultaneous MFC/NGS correlation in the "suspected CR population". Median follow-up was 62 months. Biological agreement was 87% at the 10-5 and 83% at the 10-6 cut-offs. A remarkable prognostic concordance was observed: hazard ratios in MFC-MRD and NGS-MRD-negative vs -positive patients were 0.29 and 0.27 for progression-free survival (PFS) and 0.35 and 0.31 for overall survival, respectively (p < 0.05). During maintenance, 4-year PFS was 91% and 97% in 1-year sustained MFC-MRD-negative and NGS-MRD-negative patients (10-5), respectively, and 99% and 97% in 2-year sustained MFC-MRD-negative and NGS-MRD-negative patients, regardless of treatment received. The conversion rate from pre-maintenance MRD positivity to negativity during maintenance was significantly higher with KR vs R both by MFC (46% vs 30%, p = 0.046) and NGS (56% vs 30%, p = 0.046).

Interpretation

The significant biological/clinical concordance between MFC and NGS at the same sensitivity suggests their possible use in the evaluation of one of the currently strongest predictors of outcome.

Funding

Amgen, Celgene/Bristol Myers Squibb, Multiple Myeloma Research Foundation.

Are surgical scrubbing and pre-operative disinfection of the skin in orthopaedic surgery reliable?

This study attempts to establish the actual effectiveness of pre-surgical disinfection of the patient and surgeon's hands. We evaluated bacterial density and composition on the skin of 15 patients undergoing knee arthroscopy and the left hand of two surgeons after standard disinfection with povidone-iodine. Three samples were taken after the first 6-min scrub in the first surgical operation from the periungual space of the 1 degrees finger, from the interdigital space between the 2 degrees and 3 degrees fingers and from the transverse palmar crest of the left hand of two surgeons for seven consecutive surgical sessions, for a total of 42 samples, and two samples from the pre-patellar skin and from the popliteal skin of 15 patients undergoing knee arthroscopy, for a total of 30 samples. Pre-surgical handwashing and disinfection procedures were identical in each case. Pre-surgical disinfection of the patient's skin with povidone-iodine was shown to be completely effective, with 100% of samples negative. Samples taken from the interdigital space and the palmar crest (100% of samples negative) demonstrated the efficacy of disinfection of the surgeon's hands with povidone-iodine, while the periungual space was contaminated in 50% of the samples. The bacterial strains isolated belong to the staphylococcus genus in 100% of the cases, with pathogenic strains in 29.6% of the cases. Standard pre-surgical disinfection of skin in areas easily accessible to the disinfectant is sufficient in itself to guarantee thorough sanitization. Standard scrubbing of the surgeon's hands is insufficient in eliminating bacterial contamination, including pathogenic germs, in the periungual space, where it is probably difficult for the disinfectant to come into contact with the skin.

[The nitric oxide metabolism in the hypoxic, ischemic and reperfused human skeletal muscle cell: clinical and therapeutical observations]

BACKGROUND

The biochemical and metabolic role played by nitric oxide (NO) in course of oxidative stress due to cell hypoxia, ischemia and reperfusion has a determinant relevance in the mitochondrial adaptive changes which antagonize the irreversible morpho-functional damage. In particular conditions, such as in prolonged ischemia and/or exogenous NO supplementation, this element is present in the radical form (NOO*) concurring to peroxidative cell injury. Aim of this study was to investigate these opposite NO aspects in hypoxic, ischemic and reperfused human skeletal muscle tissue.

METHODS

Skeletal muscle samples were taken during elective knee orthopedic surgery in 10 consecutive patients. The biopsies were obtained before, after 5+/-1 min and 58+/-2 min from tourniquet application and then after 18+/-3 min following muscle reperfusion. The samples, immediately frozen in liquid nitrogen, were assayed for endocellular free NO following the gas-amperometric method described by Palmerini C.

RESULTS

When compared with normoxic tissues, a significant decrease in free NO content was observed in hypoxic samples. After about 60 min of prolonged ischemia the NO levels show an evident increase, while the tissue reperfusion leads to a progressive restoration of physiological content in the cellular free nitric oxide.

CONCLUSIONS

The obtained data in hypoxic muscle cell seem to underline the pivotal role played by NO in adapting the cytochrome c oxidase oxidative activity to lower O2 bio-availability. On the other hand the prolonged ischemia leads to a consistent NOO* generation triggered by oxyradical generation and Ca2+ intracellular over load. Even if the tissue reoxygenation restores the normal NO levels it is arguable that the pre-treatment of ischemic cell with antioxidants, Ca-antagonist and Dexamethasone supplementation could represent a crucial and specific therapeutic approach to critically ill patient.

[Biochemical and metabolic aspects of oxyradical pathology in the hypoxic-ischemic reperfused human skeletal muscle tissue. Clinical markers and therapeutic approach]

BACKGROUND

Following our previous studies on the biomolecular and biochemical aspects of the human tissue oxidative damage due to hypoxia, ischemia and reperfusion, aim of the present work is to evaluate the role played by oxyradical generation in the morphofunctional cellular injury. We evaluated the tissue levels of some metabolic markers (MDA, Catalase, Uric Acid) to obtain a pathogenic picture and then a therapeutic approach closely related to the cellular biodynamics.

METHODS

A skeletal muscle samples were taken during elective knee orthopedic surgery in 20 consecutive patients. The biopsies were taken in normoxic conditions and after 5 +/- 1 and 62 +/- 3 min form tourniquet application and finally 21 +/- 2 min following muscle reperfusion. The samples were assayed for tissue Malondialdeyade (MDA), uric acid and catalase (CAT) contents with HPLC and fluorimetric procedures. All data were evaluated in terms of computerized statistical analysis.

RESULTS

When compared to normoxic tissue (1.24 +/- 0.26 nmoli.mg-1 protein), the MDA levels show a moderate increase in hypoxic (1.66 +/- 0.12) and ischemic tissue (1.78 +/- 0.13), while highly significant is the rise in reperfused muscle MDA content (5.94 +/- 0.15). The uric acid as far as CAT shows no appreciable alterations in hypoxia and ischemia. Following reoxygenation an increase in uric acid contents with a concomitant CAT tissue consumption appear evident.

CONCLUSIONS

The obtained data seem to underline the cytoprotective role played by adaptive changes in the hypoxic and ischemic human cells. On the contrary, the rapid reoxygenation of the ischemic tissue appears to start oxyradical neo-generation. In clinical and therapeutic terms these observations underline a peculiar and different approach to the critically ill patient.

Ultrastructure of periprosthetic Dacron knee ligament tissue. Two cases of ruptured anterior cruciate ligament reconstruction

Light- and electron-microscopic investigations were performed on two failed Dacron ligaments that had been removed from 2 patients shortly after failure of the implant 2-3 years after reconstruction of the anterior cruciate ligament. Two different cell populations and matrices were correlated with closeness to the Dacron threads. Fibroblasts surrounded by connective tissue with collagen fibrils were located far from the Dacron threads. Roundish cells, appearing to be myofibroblasts surrounded by a more lax connective tissue and elastic fibers, were found close to the Dacron threads. The presence of myofibroblasts and the matrix differentiation could be attributed to the different mechanical forces acting on the Dacron and on the connective tissue because of their different coefficients of elasticity. The sparse occurrence of inflammatory cells in the synovial membrane and in the connective tissue surrounding the Dacron supports the biologic inertness of this artificial material. However, the repair tissue was not structured to resist tension stresses.

Long-term follow-up of 53 cases of chronic lesion of the anterior cruciate ligament treated with an artificial Dacron Stryker ligament

Fifty-three cases of chronic lesion of the anterior cruciate ligament were followed up clinically and radiographically, and treated consecutively with an artificial Dacron Stryker ligament. An average of 29 months (range 12-53) after surgery, the authors report a high incidence of residual laxity (70.5%) and a 13% incidence of complications. There were no cases of evident synovitis, even if the authors do report a high percentage (85%) of periligamentous femoral osteolysis. Based on the results obtained, the authors believe that the Dacron Stryker ligamentous prosthesis is only indicated in cases where a biological ligament fails in patients engaged in competitive sports who request immediate activity for a limited period of time.