Texture analysis of 18F-FDG PET/CT and CECT: Prediction of refractoriness of Hodgkin lymphoma with mediastinal bulk involvement.

To recognize patients at high risk of refractory disease, the identification of novel prognostic parameters improving stratification of newly diagnosed Hodgkin Lymphoma (HL) is still needed. This study investigates the potential value of metabolic and texture features, extracted from baseline 18F-FDG Positron Emission Tomography/Computed Tomography (PET) and Contrast-Enhanced Computed Tomography scan (CECT), together with clinical data, in predicting first-line therapy refractoriness (R) of classical HL (cHL) with mediastinal bulk involvement. We reviewed 69 cHL patients who underwent staging PET and CECT. Lesion segmentation and texture parameter extraction were performed using the freeware software LIFEx 6.3. The prognostic significance of clinical and imaging features was evaluated in relation to the development of refractory disease. Receiver operating characteristic curve, Cox proportional hazard regression and Kaplan-Meier analyses were performed to examine the potential independent predictors and to evaluate their prognostic value. Among clinical characteristics, only stage according to the German Hodgkin Group (GHSG) classification system significantly differed between R and not-R. Among CECT variables, only parameters derived from second order matrices (gray-level co-occurrence matrix (GLCM) and gray-level run length matrix (GLRLM) demonstrated significant prognostic power. Among PET variables, SUVmean, several variables derived from first (histograms, shape), and second order analyses (GLCM, GLRLM, NGLDM) exhibited significant predictive power. Such variables obtained accuracies greater than 70% at receiver operating characteristic analysis and their PFS curves resulted statistically significant in predicting refractoriness. At multivariate analysis, only HISTO_EntropyPET extracted from PET (HISTO_EntropyPET ) and GHSG stage resulted as significant independent predictors. Their combination identified 4 patient groups with significantly different PFS curves, with worst prognosis in patients with higher HISTO_EntropyPET values, regardless of the stage. Imaging radiomics may provide a reference for prognostic evaluation of patients with mediastinal bulky cHL. The best prognostic value in the prediction of R versus not-R disease was reached by combining HISTO_EntropyPET with GHSG stage.

Bendamustine impairs humoral but not cellular immunity to SARS-CoV-2 vaccination in rituximab-treated B-cell lymphoma-affected patients.

Background: Patients with B-cell lymphoma are a fragile category of subjects, particularly exposed to infections and characterized by an impaired vaccination response due to the disease itself and, even more, to the chemotherapy regimen. For this reason, extensive knowledge of the immune response status of these subjects is of fundamental importance to obtain possible indications for a tailored immunization strategy. Methods: We enrolled two cohorts of patients with B-cell lymphoma under rituximab treatment or 3-24 months after treatment. In all patients, we evaluated both humoral and cellular immunological memory toward SARS-CoV-2, after standard vaccination and upon one booster dose. Results: We observed no Spike-specific IgG production in patients (n = 25) under anti-CD20 treatment, whereas patients (n = 16) vaccinated after the completion of chemotherapy showed a higher humoral response. Evaluating SARS-CoV-2-specific T-cell response, we found that patients in both cohorts had developed robust cellular immunity after vaccination. Of the 21 patients (51%) that experienced a breakthrough SARS-CoV-2 infection, only six patients developed severe disease. Interestingly, these six patients had all been treated with rituximab plus bendamustine. Notably, we observed that Spike-specific IgG levels in patients treated with rituximab plus bendamustine were absent or lower compared with those in patients treated with rituximab plus other chemotherapy, whereas Spike-specific T-cell response was not different based on chemotherapy regiment. Discussion: Our results show that, in patients with B-cell lymphoma under rituximab therapy, anti-SARS-CoV-2 mRNA vaccination induces a weak or absent humoral response but a consistent T-cell response. In addition, chemotherapy regimens with bendamustine further reduce patients' ability to mount a Spike-specific humoral response even after a long time period from chemotherapy discontinuation. These results provide evidence that different chemotherapeutics display different immunosuppressive properties that could be taken in to account in the choice of the right drug regimen for the right patient. Moreover, they question whether immunocompromised patients, particularly those treated with bendamustine, need interventions to improve vaccine-induced immune response.

Orbital Infiltration in a Patient with Waldenström Macroglobulinemia: Need for Multidisciplinary Approach and Comparison with the Literature.

The use of specific inhibitory drugs of intracellular signalling pathways (such as Bruton-Kinase inhibitors) for the treatment of Waldenström's macroglobulinaemia (WM) is a recognised risk factor for Aspergillus spp. infections. The overlapping clinical manifestations of the two diseases may require the involvement of different medical specialities. We describe the clinical course of a patient with pulmonary and encephalic aspergillosis, with concomitant orbital infiltration, which represented a difficult diagnosis: the case required a multidisciplinary approach to define the ocular lesions and an in-depth study of the literature.

Characterization of Mediastinal Bulky Lymphomas with FDG-PET-Based Radiomics and Machine Learning Techniques.

BACKGROUND: This study tested the diagnostic value of 18F-FDG PET/CT (FDG-PET) volumetric and texture parameters in the histological differentiation of mediastinal bulky disease due to classical Hodgkin lymphoma (cHL), primary mediastinal B-cell lymphoma (PMBCL) and grey zone lymphoma (GZL), using machine learning techniques. METHODS: We reviewed 80 cHL, 29 PMBCL and 8 GZL adult patients with mediastinal bulky disease and histopathological diagnoses who underwent FDG-PET pre-treatment. Volumetric and radiomic parameters were measured using FDG-PET both for bulky lesions (BL) and for all lesions (AL) using LIFEx software (threshold SUV ≥ 2.5). Binary and multiclass classifications were performed with various machine learning techniques fed by a relevant subset of radiomic features. RESULTS: The analysis showed significant differences between the lymphoma groups in terms of SUVmax, SUVmean, MTV, TLG and several textural features of both first- and second-order grey level. Among machine learning classifiers, the tree-based ensembles achieved the best performance both for binary and multiclass classifications in histological differentiation. CONCLUSIONS: Our results support the value of metabolic heterogeneity as an imaging biomarker, and the use of radiomic features for early characterization of mediastinal bulky lymphoma.

Disease correlates and clinical relevance of hereditary α-tryptasemia in patients with systemic mastocytosis.

BACKGROUND: Systemic mastocytosis (SM) encompasses a heterogeneous group of clonal disorders characterized by abnormal expansion of mast cells (MCs). Beyond KIT and other genes recurrently mutated in myeloid neoplasms, several genetic variants have been described as predisposing to the development of the disease and influencing its clinical phenotype. Increased copy number variants of the TPSAB1 gene were identified as a cause of nonclonal elevated tryptasemia and defined as hereditary α-tryptasemia (HαT). Moreover, HαT is enriched in patients with SM, where it can affect the incidence of mediator-related symptoms. OBJECTIVE: In a multicenter data set of 444 patients with MC disorders, we aimed to investigate the clinical correlates of germline TPSAB1 copy number gains. METHODS: Droplet digital PCR was performed in all cases to ascertain the presence of HαT. Clinical history along with blood values and bone marrow examination were analyzed. RESULTS: We confirmed a higher incidence of HαT+ cases (n = 59, 13.3%) in patients diagnosed with mastocytosis with respect to the general population (approximately 5%). HαT+ patients were characterized by a lower MC-associated disease burden and higher levels of tryptase. Several disease variables were coherent with this pattern, from bone marrow MC infiltration to MC-related histopathologic traits, which also accounted for a significantly higher incidence of clonal MC activation syndrome in HαT+ (10.2%) compared to HαT- (3.4%, P = .029) patients. We also confirmed that HαT+ carriers had a significantly higher frequency of anaphylaxis, without relevant differences for other clinical manifestations. CONCLUSION: These findings on a large patient series support and extend previous data, and suggest that knowledge of HαT status may be useful for personalized management of patients with SM.

Histopathology and Molecular Genetics in Systemic Mastocytosis: Implications for Clinical Management.

The diagnosis of systemic mastocytosis (SM) is based on various clinical, dermatological, serological, and hematological findings but essentially relies on histological evidence of an abnormal increase in tissue-localized mast cells (MCs). The extra-cutaneous organ most frequently affected is the bone marrow (BM), and therefore, histological examination of trephine biopsy specimens of the iliac crest is mandatory on suspicion of SM. At microscopic examination, neoplastic MCs show aberrant morphology, usually with prominent spindling. Immunohistochemistry is a useful tool in the diagnosis of SM because mast cell (MC) infiltrates may be slight and scarce, in a mixed background of lymphohistiocytic cells, eosinophils, and plasma cells. Moreover, neoplastic MCs exhibit an aberrant phenotype. Recent evidence, largely derived from molecular genetics, has enhanced the diagnostic capability of SM, also providing the basis for adequate prognostic and therapeutic evaluation. The cases herein reported illustrate the variable clinical manifestations and disease course of SM, focusing on diagnostic and therapeutic challenges. In accordance with the World Health Organization (WHO) classification and the International Consensus Classification (ICC) systems, our findings emphasize the importance of an integrated diagnostic approach for SM, with proper application of diverse assessment methodologies in order to improve SM classification and treatment effectiveness.

Compassionate use of JAK1/2 inhibitor ruxolitinib for severe COVID-19: a prospective observational study.

Overwhelming inflammatory reactions contribute to respiratory distress in patients with COVID-19. Ruxolitinib is a JAK1/JAK2 inhibitor with potent anti-inflammatory properties. We report on a prospective, observational study in 34 patients with COVID-19 who received ruxolitinib on a compassionate-use protocol. Patients had severe pulmonary disease defined by pulmonary infiltrates on imaging and an oxygen saturation ≤ 93% in air and/or PaO2/FiO2 ratio ≤ 300 mmHg. Median age was 80.5 years, and 85.3% had ≥ 2 comorbidities. Median exposure time to ruxolitinib was 13 days, median dose intensity was 20 mg/day. Overall survival by day 28 was 94.1%. Cumulative incidence of clinical improvement of ≥2 points in the ordinal scale was 82.4% (95% confidence interval, 71-93). Clinical improvement was not affected by low-flow versus high-flow oxygen support but was less frequent in patients with PaO2/FiO2 < 200 mmHg. The most frequent adverse events were anemia, urinary tract infections, and thrombocytopenia. Improvement of inflammatory cytokine profile and activated lymphocyte subsets was observed at day 14. In this prospective cohort of aged and high-risk comorbidity patients with severe COVID-19, compassionate-use ruxolitinib was safe and was associated with improvement of pulmonary function and discharge home in 85.3%. Controlled clinical trials are necessary to establish efficacy of ruxolitinib in COVID-19.

Mutation-enhanced international prognostic systems for essential thrombocythaemia and polycythaemia vera.

Survival prediction in essential thrombocythaemia (ET) and polycythaemia vera (PV) is currently based on clinically-derived variables; we examined the possibility of integrating genetic information for predicting survival. To this end, 906 molecularly-annotated patients (416 Mayo Clinic; 490 University of Florence, Italy), including 502 ET and 404 PV, were recruited. Multivariable analysis identified spliceosome mutations to adversely affect overall (SF3B1, SRSF2 in ET and SRSF2 in PV) and myelofibrosis-free (U2AF1, SF3B1 in ET) survival; TP53 mutations predicted leukaemic transformation in ET; "adverse" mutations occurred in 51 (10%) ET and 8 (2%) PV patients. We confirmed the independent survival effect of adverse mutations [hazard ratio (HR) 2·4, 95% CI 1·6-3·5], age >60 years (6·6, 4·6-9·7), male sex (1·8, 1·3-2·4) and leukocytosis ≥11 × 109 /l (1·6, 1·1-2·2), in ET, and adverse mutations (7·8, 3·1-17·0), age >67 years (5·4, 3·6-8·1), leukocytosis ≥15 × 109 /l (2·8, 1·8-4·2) and thrombosis history (2·0, 1·4-2·9), in PV. HR-based risk point allocation allowed development of three-tiered mutation-enhanced international prognostic systems (MIPSS) which were validated in both cohorts and performance was shown to be superior to conventional scoring systems. Spliceosome mutations enhance survival prediction in ET and PV and identify patients at risk for fibrotic progression. TP53 mutations predict leukaemic transformation in ET.

Splanchnic vein thromboses associated with myeloproliferative neoplasms: An international, retrospective study on 518 cases.

Myeloproliferative Neoplasms (MPN) course can be complicated by thrombosis involving unusual sites as the splanchnic veins (SVT). Their management is challenging, given their composite vascular risk. We performed a retrospective, cohort study in the framework of the International Working Group for MPN Research and Treatment (IWG-MRT), and AIRC-Gruppo Italiano Malattie Mieloproliferative (AGIMM). A total of 518 MPN-SVT cases were collected and compared with 1628 unselected, control MPN population, matched for disease subtype. Those with MPN-SVT were younger (median 44 years) and enriched in females compared to controls; PV (37.1%) and ET (34.4%) were the most frequent diagnoses. JAK2V617F mutation was highly prevalent (90.2%), and 38.6% of cases had an additional hypercoagulable disorder. SVT recurrence rate was 1.6 per 100 patient-years. Vitamin K-antagonists (VKA) halved the incidence of recurrence (OR 0.48), unlike cytoreduction (OR 0.96), and were not associated with overall or gastrointestinal bleeding in multivariable analysis. Esophageal varices were the only independent predictor for major bleeding (OR 17.4). Among MPN-SVT, risk of subsequent vascular events was skewed towards venous thromboses compared to controls. However, MPN-SVT clinical course was overall benign: SVT were enriched in PMF with lower IPSS, resulting in significantly longer survival than controls; survival was not affected in PV and slightly reduced in ET. MPN-U with SVT (n = 55) showed a particularly indolent phenotype, with no signs of disease evolution. In the to-date largest, contemporary cohort of MPN-SVT, VKA were confirmed effective in preventing recurrence, unlike cytoreduction, and safe; the major risk factor for bleeding was esophageal varices that therefore represent a major therapeutic target.