Effect of delayed cell infusion in patients with large B-cell lymphoma treated with chimeric antigen receptor T-cell therapy

Complications occurring after lymphodepleting chemotherapy (LDC) may delay chimeric antigen receptor (CAR) T-cell infusion. The effect of these delays on clinical outcomes is unclear. We performed a retrospective analysis of 240 patients with relapsed/refractory large B-cell lymphoma treated with standard-of-care axicabtagene ciloleucel (axi-cel) and identified 40 patients (16.7%) who had delay in axi-cel infusion. Of these, 85% had delay due to infection. At time of LDC initiation, patients with delayed infusion had lower absolute neutrophil count (P=0.006), lower platelets (P=0.004), lower hemoglobin (P<0.001) and higher C-reactive protein (P=0.001) than those with on-time infusion. Patients with delayed infusion had lower day 30 overall response rates (59.0% vs. 79.4%; P=0.008) and shorter median progression-free survival (PFS) (3.5 vs. 8.2 months; P=0.002) and overall survival (7.8 vs. 26.4 months; P=0.046) than those with on-time infusion. The association with PFS was maintained on multivariate analysis. There was also an association between extent of delay and survival, with shorter median PFS in patients who had delays of 2-5 days (1.8 vs. 8.2 months; P=0.001) and >5 days (4.6 vs. 8.2 months; P=0.036), but not 1 day (5.7 vs. 8.2 months; P=0.238). Following propensity score matching, patients with delayed infusion continued to have shorter median PFS (3.5 vs. 6.0 months; P=0.015). Levels of pro-inflammatory cytokines on day of infusion were significantly higher in patients with delayed infusion. Together, these findings suggest that delays in CAR T-cell administration after initiation of LDC are associated with inferior outcomes. Further studies are needed to guide strategies to improve efficacy in such patients.

Impact of cumulative dose of brentuximab vedotin on outcomes of frontline therapy for advanced-stage Hodgkin lymphoma

In the pivotal study ECHELON-1, brentuximab vedotin (BV), doxorubicin, vinblastine, and dacarbazine (A + AVD) demonstrated superior efficacy compared with bleomycin + AVD for the treatment of advanced-stage classic Hodgkin lymphoma (cHL). However, there are minimal available data regarding the frequency of dose reductions or omission of BV during curative therapy and the potential impact on patient outcomes. In a real-world analysis, we retrospectively reviewed the characteristics and outcomes of 179 patients with stage III or IV cHL treated with frontline A + AVD from January 2010 to April 2022. Treatment consisted of up to 1.2 mg/kg of BV and standard dose AVD IV on days 1 and 15 of each 28-day cycle for up to 6 cycles. At the time of treatment, the median patient age was 37 years, and a high-risk International Prognostic Score was observed in 46% of patients. Overall, 91% of patients received 6 cycles of AVD; 55% of patients did not receive the intended cumulative dose of BV (CDB); 28% of patients received two-thirds or less than the planned CDB. At a median follow-up time of 27.4 months (95% confidence interval [CI], 24.8-29), the median progression-free survival (PFS) was not reached, and the 12-month PFS was 90.3% (95% CI, 85.9-95.0). The impact of CDB on PFS was not significant (P = .15), nor was high CDB significantly associated with increased adverse events. In real-world experience, A + AVD is a highly effective treatment for patients with advanced-stage cHL, including for patients with prominent dose reductions of BV.

Safety of Concurrent Radiation Therapy With Brentuximab Vedotin in the Treatment of Lymphoma

Purpose

Purpose: Radiation therapy (RT) and the antibody-drug conjugate brentuximab vedotin (BV) are standard-of-care treatment options for patients with certain B and T-cell lymphomas; however, there are limited data exploring the safety of concurrent BV and RT (BVRT).

Methods and Materials

We performed a single institutional retrospective review of 44 patients who received BVRT.

Results

Twenty percent of patients (9/44) developed new grade 2 or higher (G2+) hematologic toxicity (HT) after BVRT, which was associated with radiation dose (median dose of 35 Gy in those with new G2+ HT compared with 15 Gy in those without; P < .001). Acute G2+ elevation in aspartate transaminase or alanine transaminase level was associated with administration of concurrent chemotherapy with BVRT (57% vs 21%; P = .047) but was not associated with any RT factors. Local control (LC) was achieved in 24 of 42 patients (57%) with available follow-up. Ten patients (23%) proceeded to stem cell transplant or cellular therapy after BVRT at a median of 48 days (interquartile range, 27-188 days). At last follow-up, 10 patients (23%) remained without evidence of disease.

Conclusions

Our analysis demonstrates that the combination of BV and RT is well tolerated, though care should be taken during RT planning to reduce the risk of HT. This combination can be considered for patients in need of both local and systemic disease control.

Prolonged cytopenia following CD19 CAR T cell therapy is linked with bone marrow infiltration of clonally expanded IFNγ-expressing CD8 T cells

Autologous anti-CD19 chimeric antigen receptor T cell (CAR T) therapy is highly effective in relapsed/refractory large B cell lymphoma (rrLBCL) but is associated with toxicities that delay recovery. While the biological mechanisms of cytokine release syndrome and neurotoxicity have been investigated, the pathophysiology is poorly understood for prolonged cytopenia, defined as grade ≥3 cytopenia lasting beyond 30 days after CAR T infusion. We performed single-cell RNA sequencing of bone marrow samples from healthy donors and rrLBCL patients with or without prolonged cytopenia and identified significantly increased frequencies of clonally expanded CX3CR1hi cytotoxic T cells, expressing high interferon (IFN)-γ and cytokine signaling gene sets, associated with prolonged cytopenia. In line with this, we found that hematopoietic stem cells from these patients expressed IFN-γ response signatures. IFN-γ deregulates hematopoietic stem cell self-renewal and differentiation and can be targeted with thrombopoietin agonists or IFN-γ-neutralizing antibodies, highlighting a potential mechanism-based approach for the treatment of CAR T-associated prolonged cytopenia.

A non-antibiotic-disrupted gut microbiome is associated with clinical responses to CD19-CAR-T cell cancer immunotherapy

Increasing evidence suggests that the gut microbiome may modulate the efficacy of cancer immunotherapy. In a B cell lymphoma patient cohort from five centers in Germany and the United States (Germany, n = 66; United States, n = 106; total, n = 172), we demonstrate that wide-spectrum antibiotics treatment ('high-risk antibiotics') prior to CD19-targeted chimeric antigen receptor (CAR)-T cell therapy is associated with adverse outcomes, but this effect is likely to be confounded by an increased pretreatment tumor burden and systemic inflammation in patients pretreated with high-risk antibiotics. To resolve this confounding effect and gain insights into antibiotics-masked microbiome signals impacting CAR-T efficacy, we focused on the high-risk antibiotics non-exposed patient population. Indeed, in these patients, significant correlations were noted between pre-CAR-T infusion Bifidobacterium longum and microbiome-encoded peptidoglycan biosynthesis, and CAR-T treatment-associated 6-month survival or lymphoma progression. Furthermore, predictive pre-CAR-T treatment microbiome-based machine learning algorithms trained on the high-risk antibiotics non-exposed German cohort and validated by the respective US cohort robustly segregated long-term responders from non-responders. Bacteroides, Ruminococcus, Eubacterium and Akkermansia were most important in determining CAR-T responsiveness, with Akkermansia also being associated with pre-infusion peripheral T cell levels in these patients. Collectively, we identify conserved microbiome features across clinical and geographical variations, which may enable cross-cohort microbiome-based predictions of outcomes in CAR-T cell immunotherapy.

PD-L1+ macrophages are associated with favorable features in primary mediastinal (thymic) large B-cell lymphoma

Primary mediastinal (thymic) large B-cell lymphoma (PMBCL) is a rare, aggressive subtype of non-Hodgkin lymphoma and has a complex inflammatory microenvironment. Although most patients can be cured with standard-of-care immunochemotherapy, patients who have disease relapse have an unfavorable prognosis. Pre-treatment prognostic biomarkers in PMBCL are needed. In this retrospective study, we analyzed the clinical features and outcomes of PMBCL patients and their association with immune cell subpopulations identified by multiplex immunofluorescence at initial diagnosis. Two different antibody panels were used to assess macrophages in tissue biopsy specimens collected before the initiation of induction therapy. Twelve PMBCL patients, including five patients who had disease relapse, were included in the analysis. At a median follow-up time of 32.2 months, the median progression-free and overall survival durations were not reached. Our findings suggest that a high density of PD-L1⁺ macrophages is associated with favorable features, such as early disease stage and the absence of B-symptoms, and indicate that a high percentage of PD-L1⁺ macrophages and high densities of CD30⁺PD-L1⁺ cells and CD30⁺ cells might be associated with a lower risk of relapse within 12 months of therapy initiation. Further studies are needed to develop a biomarker signature predictive of treatment response with therapeutic consequences for patients with newly diagnosed PMBCL.

Cardiovascular events in patients treated with chimeric antigen receptor t-cell therapy for aggressive B-cell lymphoma

Standard of care (SOC) chimeric antigen receptor (CAR) T-cell therapies such as axicabtagene ciloleucel (axi-cel) and tisagenlecleucel (tisa-cel) are associated with multisystem toxicities. There is limited information available about cardiovascular (CV) events associated with SOC axi-cel or tisa-cel. Patients with CV comorbidities, organ dysfunction, or lower performance status were often excluded in the clinical trials leading to their Food and Drug Adminsitration approval. An improved understanding of CV toxicities in the real-world setting will better inform therapy selection and management of patients receiving these cellular therapies. Here, we retrospectively reviewed the characteristics and outcomes of adult patients with relapsed/refractory large B-cell lymphoma treated with SOC axi-cel or tisa-cel. Among the 165 patients evaluated, 27 (16%) developed at least one 30-day (30-d) major adverse CV event (MACE). Cumulatively, these patients experienced 21 arrhythmias, four exacerbations of heart failure/cardiomyopathy, four cerebrovascular accidents, three myocardial infarctions, and one patient died due to myocardial infaction. Factors significantly associated with an increased risk of 30-d MACE included age ≥60 years, an earlier start of cytokine release syndrome (CRS), CRS ≥ grade 3, long duration of CRS, and use of tocilizumab. After a median follow-up time of 16.2 months (range, 14.3-19.1), the occurrence of 30-d MACE was not significantly associated with progression-free survival or with overall survival. Our results suggest that the occurrence of 30-d MACE is more frequent among patients who are elderly, with early, severe, and prolonged CRS. However, with limited follow-up, larger prospective studies are needed, and multidisciplinary management of these patients is recommended.

CRP and ferritin in addition to the EASIX score predict CAR-T-related toxicity

The Endothelial Activation and Stress Index (EASIX) score, defined as [(creatinine × lactate dehydrogenase [LDH])/platelets], is a marker of endothelial activation that has been validated in the allogeneic hematopoietic stem cell transplant setting. Endothelial activation is one of the mechanisms driving immune-mediated toxicities in patients treated with chimeric antigen receptor-T (CAR-T)-cell therapy. This study's objective was to evaluate the association between EASIX and other laboratory parameters collected before lymphodepletion and the subsequent onset of cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS) those patients. Toxicity data were collected prospectively on 171 patients treated with axicabtagene ciloleucel (axi-cel) for large B-cell lymphoma (LBCL). CRS grades 2 to 4 were diagnosed in 81 (47%) patients and ICANS grades 2 to 4 in 84 (49%). EASIX combined with ferritin (EASIX-F) identified 3 risk groups with CRS grades 2 to 4 cumulative incidence of 74% (hazards ratio [HR], 4.8; 95% confidence interval [CI], 2.1-11; P < .001), 49% (HR, 2.3; 95% CI, 1.02-5; P = .04), and 23% (reference), respectively. EASIX combined with CRP and ferritin (EASIX-FC) identified 3 risk groups with an ICANS grade 2 to 4 cumulative incidence of 74% (HR, 3.6; 95% CI, 1.9-6.9; P < .001), 51% (HR, 2.1; 95% CI, 1.1-3.9; P = .025), and 29% (reference). Our results indicate that common laboratory parameters before lymphodepletion correlate with CAR-T-related toxicities and can help support clinical decisions, such as preemptive toxicity management, hospitalization length, and proper setting for CAR-T administration.

Outcome of relapsed and refractory nodular lymphocyte-predominant Hodgkin lymphoma: a North American analysis

Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) is a rare entity, with limited data on the outcome in the relapsed/refractory setting. We evaluated the outcome of all patients diagnosed between 04/1979 and 01/2019 with relapsed or progressive NLPHL after initial active therapy at two institutions, refractory disease being defined as lack of response to treatment and/or relapse within three months of treatment. NLPHL patients with histological evidence of transformation at time of first relapse or progression were excluded. In total, 69 patients with recurrent NLPHL were included in the study. After a median follow-up after initial diagnosis of 14 years (range, 0·5-46 years), median progression-free survival after front-line treatment (PFS-1) was four years. Second-line therapy included chemotherapy in 28 (41%) patients, biological therapy (rituximab, lenalidomide or brentuximab vedotin) in 14 (20%), high-dose chemotherapy followed by autologous stem cell transplant in 14 (20%) and radiation therapy (RT) alone in 10 (15%). The five-year PFS after second-line therapy (PFS-2) was 68% [95% confidence interval (CI), 54-79%] but the five-year overall survival (OS) after second-line therapy (OS-2) remained excellent, at 94% (95% CI, 85-99%). Due to excellent outcome in case of recurrence, studies aimed at characterizing its biology to guide therapy de-escalation are needed.

Longitudinal single-cell profiling reveals molecular heterogeneity and tumor-immune evolution in refractory mantle cell lymphoma

The mechanisms driving therapeutic resistance and poor outcomes of mantle cell lymphoma (MCL) are incompletely understood. We characterize the cellular and molecular heterogeneity within and across patients and delineate the dynamic evolution of tumor and immune cell compartments at single cell resolution in longitudinal specimens from ibrutinib-sensitive patients and non-responders. Temporal activation of multiple cancer hallmark pathways and acquisition of 17q are observed in a refractory MCL. Multi-platform validation is performed at genomic and cellular levels in PDX models and larger patient cohorts. We demonstrate that due to 17q gain, BIRC5/survivin expression is upregulated in resistant MCL tumor cells and targeting BIRC5 results in marked tumor inhibition in preclinical models. In addition, we discover notable differences in the tumor microenvironment including progressive dampening of CD8+ T cells and aberrant cell-to-cell communication networks in refractory MCLs. This study reveals diverse and dynamic tumor and immune programs underlying therapy resistance in MCL.

The impact of cell-of-origin, MYC/Bcl-2 dual expression and MYC rearrangement on disease relapse among early stage diffuse large B-cell lymphoma patients treated with combined modality therapy

We addressed the prognostic impact of cell-of-origin (COO), MYC and Bcl-2 overexpression as well as isolated MYC rearrangement among 111 patients with limited stage diffuse large B-cell lymphoma (DLBCL) treated with consolidative radiation therapy (RT) after a metabolic complete response to immunochemotherapy. With a median follow-up of 31.1 months (95% CI 27.4 - 34.8), 4 relapses occurred. The 3-year progression free survival (PFS), overall survival (OS), and loco-regional relapse free survival (LRFS) for the cohort were 95%, 96%, and 100%, respectively. There were no differences in OS, PFS, or LRFS based on COO or MYC/Bcl-2 dual expression (DE). Similarly, patients with MYC translocations without BCL2 or BCL6 rearrangements did not have worse outcomes. Consolidative RT produced excellent local control, regardless of DLBCL biology, with one late in-field failure.

Cardiovascular Complications of Chimeric Antigen Receptor T-Cell Therapy: The Cytokine Release Syndrome and Associated Arrhythmias

In recent years, cancer treatment has evolved, and new therapies have been introduced with significant improvement in prognosis. The immunotherapies stand out owing to their efficacy and remission rate. Chimeric antigen receptor (CAR) T-cell therapy is a part of this new era of therapies. Chimeric antigen receptor T-cell therapy is a form of adoptive cellular therapy that uses a genetically encoded CAR in modified human T cells to target specific tumor antigens in a nonconventional, non-major histocompatibility complex (MHC) protein presentation. Chimeric antigen receptor T-cell therapy successfully identifies tumor antigens and through activation of T cells destroys tumoral cells. It has been found to efficiently induce remission in patients who have been previously treated for B-cell malignancies and have persistent disease. As the use of this novel therapy increases, its potential side effects also have become more evident, including major complications like cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS). Cytokine release syndrome is a major systemic inflammatory process as a result of massive cytokine production by the proliferating and activated CAR T cells in which multiple interleukins and immune cells contribute to the inflammatory response. Cytokine release syndrome has been associated with cardiovascular life-threatening complications including hypotension, shock, tachycardia, arrhythmias, left ventricular dysfunction, heart failure, and cardiovascular death. Arrhythmias, among its major complications, vary from asymptomatic prolonged corrected QT interval (QTc) to supraventricular tachycardia, atrial fibrillation, flutter, and ventricular arrhythmias like Torsade de pointes. This article focuses on the cardiovascular complications and arrhythmias associated with CRS and CAR T-cell therapy.

Partial omission of bleomycin for early-stage Hodgkin lymphoma patients treated with combined modality therapy: Does incomplete ABVD lead to inferior outcomes?

Classical Hodgkin lymphoma (HL) patients achieve excellent outcomes; therefore, treatment de-escalation strategies to spare toxicity have been prioritized. In a large randomized trial of early stage HL patients, omission of chemotherapeutic agents including bleomycin from the standard ABVD (doxorubicin, bleomycin, vinblastine, dacarbazine) regimen was not found to be non-inferior; however the effect of partial omission is unknown. We investigated the effect of bleomycin omission on outcome for 150 early stage HL patients. At eight years, freedom from relapse was 99% for both patients who received complete or incomplete bleomycin, which is reassuring for patients requiring bleomycin omission due to toxicity.

Pretreatment SUVmax may influence the clinical benefit of BR over R-CHOP in patients with previously untreated FL

In 2 randomized phase 3 trials BR resulted in longer progression-free survival (PFS) than frontline R-CHOP in patients with indolent and mantle cell lymphoma. However, in subset analyses of follicular lymphoma (FL), the results were incongruent. We conducted a retrospective matched-pair analysis to compare the outcome of patients with advanced stage FL, receiving frontline BR (N = 73) or R-CHOP (N = 73), matched by age, gender, stage, and FL International Prognostic Index score. On multivariable analysis, baseline maximum standardized uptake value (SUV_max) >13 was associated with use of R-CHOP (p = .001). After a median follow-up of 69 months for the BR arm and 126 months for the R-CHOP arm, 5-year PFS was 80% and 70%, respectively (p = .07). After adjusting for SUV_max >13, the trend for better PFS in BR was not maintained. Prospective studies are needed to validate the role of pretreatment SUV_max as a stratification factor in future randomized therapeutic trials in FL.

An international multicenter retrospective analysis of patients with extranodal marginal zone lymphoma and histologically confirmed central nervous system and dural involvement

Marginal zone lymphoma of the central nervous system (CNS MZL) is rare. The clinical features, treatment, and prognosis are not well characterized. We performed a multicenter retrospective study of CNS MZL. Twenty-six patients were identified: half with primary and half with secondary CNS involvement. The median age was 59 years (range 26-78), 62% female and 79% with ECOG performance status ≤ 1. The most common disease site was the dura (50%). Treatment was determined by the treating physician and varied substantially. After a median follow up of 1.9 years, the estimated 2-year progression-free (PFS) and overall survival (OS) rates were 59% and 80%, respectively. Secondary CNS MZL was associated with 2-year OS of 58%. CNS MZL is rare, but relative to other forms of CNS lymphoma, outcomes appear favorable, particularly among the subset of patients with dural presentation and primary CNS presentation.

Acute Pancreatitis Associated with Ixazomib in a Multiple Myeloma Patient

BACKGROUND

Acute pancreatitis is an uncommon complication of anti-myeloma agents. Ixazomib is a first-in-class oral proteasome inhibitor to receive regulatory approval for the treatment of multiple myeloma. This case report describes the first case of ixazomib-associated pancreatitis.

CASE PRESENTATION

An 80-year-old female with relapsed multiple myeloma presented with severe diarrhea, nausea, vomiting, abdominal pain, and acute renal failure 3 weeks after starting ixazomib and dexamethasone for disease progression. An extensive workup revealed acute pancreatitis without a definitive cause. Her condition improved with supportive measures and the discontinutation of ixazomib. The latter was suspected as the probable etiology of the patient's acute pancreatitis, given no clear alternative causes and the temporal relationship between initiating ixazomib and the development of her symptoms.

CONCLUSIONS

Practitioners should include acute pancreatitis as part of their differential diagnosis in patients on ixazomib treatment who present with gastrointestinal symptoms.

Current trials for frontline therapy of mantle cell lymphoma

Mantle cell lymphoma (MCL) is a rare and incurable subtype of non-Hodgkin’s lymphoma that generally affects older individuals. However, the use of high-dose therapy and autologous stem cell transplant has improved significantly the prognosis of this hematological malignancy, but at the cost of increased toxicities, such as acute toxic death and secondary malignancies. But thanks to a rising understanding of the biology of MCL, the explosion of specifically targeted new efficacious agents, immunotherapy agents, and cellular therapies in the frontline setting, the prognosis of MCL is expected to improve dramatically.

The initial treatment of MCL is currently not standardized and the therapeutic landscape of MCL is rapidly evolving. This review provides an extensive overview of the current frontline therapy trials for MCL and presents the results of innovative regimen, including some integrating novel agents and desintensified chemotherapy.

Carfilzomib boosted combination therapy for relapsed multiple myeloma

Carfilzomib is a proteasome inhibitor that binds selectively and irreversibly to the 20S proteasome, the proteolytic core particle within the 26S proteasome, resulting in the accumulation of proteasome substrates and ultimately growth arrest and apoptosis of tumor cells. The development and ultimate approval of this medication by regulatory agencies has been an important step toward improving clinical outcomes in multiple myeloma. Although initially approved as a single agent for the treatment of multiply relapsed and/or refractory myeloma, in the USA, it is now widely used in the early relapse setting in combination with lenalidomide and dexamethasone. Carfilzomib has also been studied in combination with second-generation immunomodulatory drugs, histone deacetylase inhibitors, alkylating agents and other novel medications. In this review article, we will discuss the efficacy, safety, tolerability and quality of life of carfilzomib-based combination therapies, as well as novel agents, for relapsed multiple myeloma.

MRI of fistula-in-ano: a comparison of endoanal coil with external phased array coil techniques

PURPOSE

The objective of our study was to compare MRI of fistulas-in-ano using an endoanal coil with that using a pelvic phased array coil and to assess the value of a combined approach by correlating the findings with those at surgery.

METHOD

Twenty consecutive patients with clinical suspicion of perianal sepsis were studied using an endoanal coil immediately followed by a phased array coil. T1 weighted and STIR images in transverse and coronal planes were made with each coil and analysed by noting the presence and site of a collection and primary track, the position of any internal opening, and subcutaneous or supralevator extension. Operative findings were similarly recorded.

RESULTS

Of 20 patients with suspected fistulas, 8 had simple fistulas, 8 had complex fistulas, and 4 had no current evidence of infection. The concordance between MR and surgery for identifying the presence and site of the collection, the primary track, and the internal opening in both simple and complex cases was superior using the endoanal coil as compared with the phased array. Both coils together reflected the findings of the endoanal coil used alone. However, for supralevator/subcutaneous extension, concordance was superior using the phased array compared with the endoanal coil, and a combined approach reflected the values of the phased array coil used alone.

CONCLUSION

Endoanal MRI is highly sensitive in the delineation of fistulas-in-ano. In combination with phased array techniques, it provides valuable preoperative assessment in both simple and complex cases.

Magnetic resonance imaging of spinal cord in multiple sclerosis by fluid-attenuated inversion recovery

Magnetic resonance imaging examination of the upper spinal cord was done in sixteen adult patients with clinically definite multiple sclerosis (MS) by T2 weighted fluid attenuated inversion recovery (FLAIR) scanning in which the signal from cerebrospinal fluid was suppressed. These scans were compared with matched images obtained with conventional T1 and T2 weighted pulse sequences (including contrast enhancement). 6 lesions (five patients) were seen with the conventional scans and 37 lesions (fourteen patients) were seen with the FLAIR scans. The FLAIR sequence considerably improves the ability of MRI to demonstrate spinal involvement in MS.

Ultrasound, CT, and MRI comparison in primary and secondary tumors of the liver

Thirty-five patients with surgically removed or percutaneous biopsy-proven tumors were examined by ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI). This retrospective study describes the appearance of the primary tumors and metastases and compares the sensitivity and specificity of the 3 imaging methods. Ultrasound, CT, and MRI examinations as well as clinical, operative, and/or histologic data were available for all 35 patients. Paramagnetic contrast agent gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA) was used in 23 patients and a short TI inversion recovery MRI sequence was used in 23 patients, in addition to various spin echo MRI sequences. Thirteen patients were examined using both Gd-DTPA and the short TI inversion recovery sequence. Our comparative study--based on the following criteria: detection, size, location of the tumor, and portal vein involvement and bile duct dilatation--demonstrated an advantage of MRI over ultrasound in 16 of 35 cases, equal results in 17 of 35 cases and a disadvantage of MRI compared to ultrasound in 2 of 35 cases. With the identical criteria, MRI proved to be more informative than CT in 10 of 35 cases, equal in 21 of 35 cases, and less informative in 4 of 35 cases.

The MR contribution after CT demonstration of supratentorial mass effect without additional localising features

The contribution of magnetic resonance (MR) imaging was retrospectively evaluated in 24 patients in whom CT demonstrated a supratentorial mass effect without significant additional localising features. Using a combination of T1-weighted inversion recovery (IR) and T2-weighted spin echo sequences, the MR images localised the lesion with greater precision than CT in 80% of cases. Areas of contrast enhancement were visible on the IR images in five of nine (56%) patients assessed after intravenous gadolinium-diethylenetriamine pentaacetic acid, where no comparable enhancement was seen on CT. Twenty of the 24 patients subsequently underwent surgery; eight had biopsies and 12 had resections. Magnetic resonance accurately predicted the site of the tumour in all these patients. Three of the remaining four cases were treated with radiotherapy on the basis of the MR findings without a tissue diagnosis being sought. Magnetic resonance produces better localization than CT and provides a sound basis for further diagnostic and therapeutic procedures.

Magnetic resonance imaging of the solitary hepatic mass: direct correlation with pathology and computed tomography

Magnetic resonance images (MRI) of the liver were obtained using a combination of short time inversion recovery (STIR) and spin echo (SE) sequences. These were correlated with comparable tissue slices generated from resected specimens obtained at partial hepatectomy. All 10 cases appeared to have solitary masses on contrast enhanced computed tomography (CT). Histological examination revealed five primary tumours (two hepatocellular carcinomas, two haemangiomas and one cholangiocarcinoma) and five metastatic tumours. The STIR images demonstrated a high signal intensity in all areas of viable tumour involvement and reduced signal intensity in regions of confluent necrosis with superimposed haemorrhage or calcification. This sequence also demonstrated additional areas of high signal intensity adjacent to several lesions which were not visible on CT. Microscopy of these regions in the specimens demonstrated no tumour involvement or steatosis and their precise cause remains obscure. All the lesions demonstrated on the CT images were visible on MRI and no additional lesions were discovered on detailed microscopical examination of the specimens. Delineation of the extent of the cholangiocarcinoma was a problem with both techniques. MRI showed no major advantage over CT except for a higher contrast of the lesion compared with normal liver and also a better delineation of the tumour mass.

Bone marrow in leukemia and aplastic anemia: MR imaging before, during, and after treatment

Serial magnetic resonance (MR) studies of the cervical bone marrow were performed in five patients undergoing bone marrow transplantation for chronic granulocytic leukemia and in four patients with aplastic anemia who were treated with antilymphocytic globulin. Findings were compared with those from a group of healthy volunteers. Chemical shift imaging techniques were used to exploit the presence of protons in fat and water in the red marrow. Characteristic changes were seen in aplastic anemia before treatment, but derivation of images representing fat and water fractions was necessary to distinguish leukemic marrow. Acute changes during the treatment of leukemia may reflect the effects of chemotherapy and radiation therapy, whereas changes in the chronic phase of both diseases may prove useful in predicting treatment outcome. MR studies are likely to be useful in the assessment and treatment of hematologic disorders.

Contrast-enhanced magnetic resonance imaging of tumours of the central nervous system: a clinical review

The clinical application of the intravascular paramagnetic contrast agent gadolinium-DTPA for magnetic resonance imaging (MRI) imaging of tumours of the central nervous system (CNS) has been assessed over the past 3 years. Various patterns of contrast enhancement were observed, and situations in MRI where the administration of contrast medium may be useful have been defined. These include lesions which are isointense with normal brain matter, the separation of tumour from surrounding oedema, evaluation of the degree of blood-brain barrier breakdown, delineation of tumours obscured by overlying calcification on computed tomography (CT) and in the investigation of lesions in anatomical areas where CT has known limitations (brain stem, cervical spine). Changes in relaxation times in normal and abnormal tissues following contrast medium, toxicity and dosage of gadolinium-DTPA, and MRI pulse sequence techniques are reviewed.

Magnetic resonance imaging of the retroperitoneum

The results of magnetic resonance imaging (MRI) examinations in 50 patients with histological or clinical diagnoses of retroperitoneal disorders and 20 normal volunteers are presented. An increase in relaxation time (T1) was recognised in most pathological conditions except for four liposarcomas and one adrenal cortical neoplasm and one metastatic lesion of the same gland. Inversion recovery (IR) provided the best tissue contrast, enabling the detection of small lesions. Flow-dependent sequences and sagittal imaging planes were particularly helpful in the evaluation of aortic aneurysms. Ferric ammonium citrate used as an oral paramagnetic contrast agent and a short T1 inversion recovery sequence gave encouraging initial results in recognising bowel loops. Gadolinium-DTPA injected intravenously provided tumour enhancement, indicating vascular perfusion and demarcating tumour margins. An attempt to eliminate motion artefacts was carried out in 15 volunteers and six patients either by a new software system (respiratory ordered phase encoding) or by using short T1 inversion-recovery to suppress the high signal from fat. The same pulse sequence results were useful in demonstrating subcutaneous fistulous tracts by eliminating the adjacent fat. The actual role of MRI in the investigation of the retroperitoneum in view of current technical developments is discussed.

Nuclear magnetic resonance imaging of the heart

Satisfactory NMR images of the heart can now be obtained using ECG gated inversion recovery and spin-echo sequences. The images obtained provide good anatomical information in the transverse, coronae, and sagittal planes, particularly of the myocardium and some intracardiac structures, such as cardiac valves and papillary muscle. The pericardium can be visualized, and so can the large vessels arising from the heart. Myocardial disease, in particular ischemia and infarction, is discussed in some detail, and mention is made of the cardiac aneurysms and various types of cardiomyopathy. Congenital heart disease and pericardial pathology are also briefly discussed.

Present and future clinical position of magnetic resonance imaging

Following the appearance of the first clinical reports on magnetic resonance imaging (MRI) five years ago, stock is now taken of the clinical value of this new imaging technique and its future potential is assessed. Contrast and spatial resolution as well as specificity of CT and MRI are compared and the multiplicity of sequences, multiplanar facility, and flexibility of MRI over CT are analyzed. The dominant role of MRI over CT in the study of some disorders of the central nervous system is assessed and so are the limitations. In this context the usefulness of paramagnetic contrast media is also evaluated. The difficulties of body imaging are discussed. The solutions of overcoming cardiac and respiratory motions artifacts are evaluated and areas where MRI has already achieved a high level of clinical application are identified. Mention is made of additional information obtainable by MRI as, for example, sodium imaging, blood flow measurements, and the combination of imaging with spectroscopy. Possible future prospects are analyzed, for example, high-resolution imaging, alternative sequences to those commonly used in particular the short TI IR sequence (STIR), chemical shift imaging, and the possibility of utilizing susceptibility for imaging purposes. The problem of radiofrequency receiver coil design is approached and so is the choice of magnetic fields. The future relationship of MRI with established noninvasive techniques is stressed.

Periventricular leukomalacia: evaluation with MR imaging

We reviewed 24 magnetic resonance (MR) images of 12 infants diagnosed as having periventricular leukomalacia based on ultrasound results. Abnormalities were identified on the MR images of every patient and were divided into three categories: distribution of low-signal-intensity areas within the cerebral white matter, degree of ventriculomegaly and brain atrophy, and extent of myelination. Follow-up examinations on six patients were also compared for significant changes. Abnormalities noted on MR images that most consistently related to poor outcome for the patient were low-signal-intensity lesions involving all four cerebral lobes, moderate to severe delays in myelination, lack of progression of myelination, and moderate to severe cortical atrophy. MR imaging was able to depict the extent and progression of myelination, and it may be used to continue follow-up of these patients beyond the time of fontanel closure.

Gadolinium-DTPA in the assessment of liver tumours by magnetic resonance imaging

The effect of gadolinium-DTPA (Gd-DTPA, Schering AG) as a magnetic resonance imaging (MRI) contrast agent was studied in 15 patients with liver tumours. A dose of 0.1 mmol/kg was used. An analysis of the time-course of enhancement, a comparison of four different pulse sequences, and a dose-comparison study were carried out with monitoring of haematological and biochemical parameters before and after injection of Gd-DTPA. Maximum enhancement, that is, increase in signal intensity, was noted on IR1400/400/13 between 10 and 20 min after injection while on SE580/40 and SE580/80 maximum enhancement was noted 30 min after injection. In some cases enhancement was noted up to 120 minutes after injection. SR1000/13f sequences showed very little enhancement. On comparison with contrast-enhanced X-ray computed tomography (CT), enhancement was greater on MRI in seven cases, equal in six and less in two, as assessed subjectively. Additional lesions were shown in one case using Gd-DTPA compared to precontrast enhanced MRI scans. However, no additional lesions were seen on contrast-enhanced MRI scans compared to contrast-enhanced CT scans. Gd-DTPA is capable of enhancing liver tumours on MRI and may have a place in the assessment of the operability of such lesions.

The role of magnetic resonance imaging techniques in the evaluation of orbital and ocular disease

Technical developments have resulted in a great improvement in the quality of magnetic resonance imaging (MRI) of the orbit. With surface coil data acquisition spatial resolution of less than a millimetre can now be achieved, and contrast discrimination is such that the cortex and nucleus of the lens can be distinguished. The application of MRI to the diagnosis of orbital and ocular pathology was studied in a group of 51 patients with a wide range of pathology. Advantages of MRI over computed tomography (CT) included the avoidance of ionising radiation, the direct multiplanar facility and the use of flow-dependent sequences to identify pathological vessels without the need for contrast medium; although CT was superior in showing bone detail. Only a limited discrimination between different tumour types is possible by assessment of their MRI characteristics. Research is currently being directed towards achieving thinner slices, shorter data acquisition times and removal of the high signal from retrobulbar fat.

Total stabilization of the cervical spine in patients with cervical spondylotic myelopathy

Certain patients with cervical spondylotic myelopathy demonstrate instability in the upper cervical vertebral column associated with marked narrowing of the vertebral canal in the neighboring lower cervical segments. This combination of causative mechanisms creates difficulty in using routine surgical procedures, especially in elderly and severely debilitated patients. We present three cases that typify this situation and illustrate marked resolution of debilitating myelopathy through total posterior fusion of the cervical spine usually incorporating the occiput.