Should we use nomograms for risk predictions in diffuse large B cell lymphoma patients? A systematic review

Models based on risk stratification are increasingly reported for Diffuse large B cell lymphoma (DLBCL). Due to a rising interest in nomograms for cancer patients, we aimed to review and critically appraise prognostic models based on nomograms in DLBCL patients. A literature search in PubMed/Embase identified 59 articles that proposed prognostic models for DLBCL by combining parameters of interest (e.g., clinical, laboratory, immunohistochemical, and genetic) between January 2000 and 2024. Of them, 40 studies proposed different gene expression signatures and incorporated them into nomogram-based prognostic models. Although most studies assessed discrimination and calibration when developing the model, many lacked external validation. Current nomogram-based models for DLBCL are mainly developed from publicly available databases, lack external validation, and have no applicability in clinical practice. However, they may be helpful in individual patient counseling, although careful considerations should be made regarding model development due to possible limitations when choosing nomograms for prognostication.

Real-world outcomes following third or subsequent lines of therapy: A Danish population-based study on 189 patients with relapsed/refractory large B-cell lymphomas

Outcome data of patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL) beyond the second line are scarce outside of clinical trials. Novel therapies in the R/R setting have been approved based on single-arm trials, but results need to be contextualized by real-world outcomes. Medical records from 3753 Danish adults diagnosed with DLBCL were reviewed. Patients previously treated with rituximab and anthracycline-based chemotherapy who received the third or later line (3 L+) of treatment after 1 January 2015, were included. Only 189 patients with a median age of 71 years were eligible. The median time since the last line of therapy was 6 months. Patients were treated with either best supportive care (22%), platinum-based salvage therapy (13%), low-intensity chemotherapy (22%), in clinical trial (14%) or various combination treatments (32%). The 2-year OS-/PFS estimates were 25% and 12% for all patients and 49% and 17% for those treated with platinum-based salvage therapy. Age ≥70, CNS involvement, elevated LDH and ECOG ≥2 predicted poor outcomes, and patients with 0-1 of these risk factors had a 2-year OS estimate of 65%. Only a very small fraction of DLBCL patients received third-line treatment and were eligible for inclusion. Outcomes were generally poor, but better in intensively treated, fit young patients with limited disease.

Prognostic indices in diffuse large B-cell lymphoma: a population-based comparison and validation study of multiple models

Currently, the International Prognostic Index (IPI) is the most used and reported model for prognostication in patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL). IPI-like variations have been proposed, but only a few have been validated in different populations (e.g., revised IPI (R-IPI), National Comprehensive Cancer Network IPI (NCCN-IPI)). We aimed to validate and compare different IPI-like variations to identify the model with the highest predictive accuracy for survival in newly diagnosed DLBCL patients. We included 5126 DLBCL patients treated with immunochemotherapy with available data required by 13 different prognostic models. All models could predict survival, but NCCN-IPI consistently provided high levels of accuracy. Moreover, we found similar 5-year overall survivals in the high-risk group (33.4%) compared to the original validation study of NCCN-IPI. Additionally, only one model incorporating albumin performed similarly well but did not outperform NCCN-IPI regarding discrimination (c-index 0.693). Poor fit, discrimination, and calibration were observed in models with only three risk groups and without age as a risk factor. In this extensive retrospective registry-based study comparing 13 prognostic models, we suggest that NCCN-IPI should be reported as the reference model along with IPI in newly diagnosed DLBCL patients until more accurate validated prognostic models for DLBCL become available.

Bone marrow biopsy can be omitted in the diagnostic workup of CNS lymphoma of DLBCL origin: a population-based retrospective study in the PET-CT era

Currently, bone marrow (BM) biopsy (BMB) is recommended in the initial staging of patients with the presumed primary central nervous system (CNS) lymphoma (PCNSL). However, the added value of BMB in the era of positron emission tomography (PET-CT) has been challenged in other lymphoma subtypes. We analyzed BM findings in patients with biopsy-proven CNS lymphoma and a negative PET-CT scan for disease outside CNS. A comprehensive Danish population-based registry search was performed to identify all patients with CNS lymphoma of diffuse large B cell lymphoma (DLBCL) histology with available BMB results and staging PET-CT without systemic lymphoma. A total of 300 patients fulfilled the inclusion criteria. Of them, 16% had a previous history of lymphoma, while 84% were diagnosed with PCNSL. None of the patients had DLBCL in the BM. A minority (8.3%) had discordant BMB findings, mainly low-grade histologies that did not influence treatment choice in any case. In conclusion, the risk of overlooking concordant BM infiltration in patients with CNS lymphoma of DLBCL histology and negative PET-CT scan is negligible. As we did not find any patient with DLBCL in the BMB, our results suggest that BMB can be safely omitted in the diagnostic workup in patients with CNS lymphoma and a negative PET-CT.

Impact of C-reactive protein and albumin levels on short, medium, and long term mortality in patients with diffuse large B-cell lymphoma

Objectives and study design: In this population-based study of 602 patients, we amended C-reactive protein (CRP) and plasma albumin (PA) levels around the diagnosis of diffuse large B-cell lymphoma (DLBCL) to the International Prognostic Index (IPI) and assessed 0-90, 91-365, and +365-day survival.Results: The CRP did not contribute to the IPI's prognostic or discriminatory ability, regardless of time period, particularly not in models with PA. In contrast, the PA was an important contributor, especially in the 0-90 day period, but also up to one year after the diagnosis. For day 0-90, the model with the IPI only had an Area Under the Receiver Operating Characteristics (AUROC) of 0.742, whereas the IPI with PA as a continuous variable rendered an AUROC of 0.841. Especially the lower PA quartile (18-32 g/L) contributed to the worse prognosis.Conclusions: The amendment of PA to the IPI may significantly improve the short-term prognostic and discriminative ability.Key messagesThe amendment of the plasma albumin (PA) level to the International Prognostic Index significantly improved the prediction of mortality up to one year after the diagnosis of diffuse large B-cell lymphoma.It was especially the lower quartile of the PA level (18-32 g/L) that contributed to the worse prognosis.

Clinical Characteristics and Management of Patients With Concomitant Liver Cirrhosis and Lymphoma: A Systematic Review

Over the years, a rising incidence of liver cirrhosis and lymphoma has been observed. Therefore, the risk of having cirrhosis as a comorbidity increases, thus challenging treatment approaches as data on the management of these patients is lacking. We performed a systematic review to summarize papers that analyzed patients with liver cirrhosis that occurred before and/or concomitantly to lymphoma. We identified 153 papers (230 patients) through Pubmed and/or Embase search. Publications comprised predominantly of case reports and/or case series. Most patients had HCV-related cirrhosis (62.6%), and aggressive lymphoma histology (59.6%). Data on liver status was available in 55.7% of all patients, with 46.1% having decompensated liver cirrhosis. These patients experienced more often treatment reductions and/or modifications, treatment side effects, and inferior survival than those with compensated cirrhosis (median 18 months vs. median not reached). Dose reductions and/or treatment modifications primarily due to concomitant liver disease were common. Moreover, liver toxicity was observed in 33.6% of patients with provided information on treatment side effects, ranging from mild toxicity to liver failure with fatal outcomes. Again, despite treatment modification/reduction, patients with decompensated liver cirrhosis developed hepatic toxicity more frequently than patients with compensated liver disease. Although patients suffering from cirrhosis and lymphoma can tolerate standard chemoimmunotherapy, a cautious multidisciplinary approach is needed to evaluate the risks and benefits.

The clinical applicability of current prognostic models in follicular lymphoma: A systematic review

The Follicular Lymphoma International Prognostic Index (FLIPI) is widely used for risk stratification of patients with follicular lymphoma (FL). Motivated by evolvement in treatment modalities, several prognostic models for FL have been proposed recently. This systematic review aimed to identify available prognostic models for newly diagnosed FL and discuss their potential limitations. A total of ten studies fulfilled the inclusion criteria. Different clinical, laboratory, radiological, and histopathological findings were combined in prognostic models. The majority of studies developed models from clinical trial cohorts, and most lacked validation in populations treated with current treatment options. Although the FLIPI is the most widely used model for prognostication in FL patients, current prognostic models, including FLIPI, are rarely used in clinical practice for treatment decision-making. Future studies should validate the existing, or develop new prognostic models, to identify which of the current standard treatment options benefit high-risk FL patients the most.

Prognostic models in primary central nervous system lymphoma patients: A systematic review

Over the last decade, several prognostic models have been proposed for primary central nervous system lymphoma (PCNSL), but consensus on the optimal model for these patients is absent or lacking. This study aims to review available prognostic models for PCNSL and discuss their prognostic features. A comprehensive literature search performed in Pubmed/Embase identified ten studies with a variable number of analysed patients (range 32-3453), which proposed 12 prognostic models. Age and performance status were the most important prognostic factors in PCNSL and an integral part of the majority of the proposed models. However, there is no universally accepted prognostic model for PCNSL owning to a number of limitations such as a small number of patients, limited samples obtained for genetic analysis, retrospective nature of studies, single centre studies, and lack of validation. Future multicentre studies are necessary to determine the optimal prognostic model for PCNSL by combining different prognostic markers of significance.

Statistical Challenges in Development of Prognostic Models in Diffuse Large B-Cell Lymphoma: Comparison Between Existing Models - A Systematic Review

Background and Aim

Based on advances in the diagnosis, classification, and management of diffuse large B-cell lymphoma (DLBCL), a number of new prognostic models have been proposed. The aim of this study was to review and compare different prognostic models of DLBCL based on the statistical methods used to evaluate the performance of each model, as well as to analyze the possible limitations of the methods.

Methods and Results

A literature search identified 46 articles that proposed 55 different prognostic models for DLBCL by combining different clinical, laboratory, and other parameters of prognostic significance. In addition, six studies used nomograms, which avoid risk categorization, to create prognostic models. Only a minority of studies assessed discrimination and/or calibration to compare existing models built upon different statistical methods in the process of development of a new prognostic model. All models based on nomograms reported the c-index as a measure of discrimination. There was no uniform evaluation of the performance in other prognostic models. We compared these models of DLBCL by calculating differences and ratios of 3-year overall survival probabilities between the high- and the low-risk groups. We found that the highest and lowest ratio between low- and high-risk groups was 6 and 1.31, respectively, while the difference between these groups was 18.9% and 100%, respectively. However, these studies had limited duration of follow-up and the number of patients ranged from 71 to 335.

Conclusion

There is no universal statistical instrument that could facilitate a comparison of prognostic models in DLBCL. However, when developing a prognostic model, it is recommended to report its discrimination and calibration in order to facilitate comparisons between different models. Furthermore, prognostic models based on nomograms are becoming more appealing owing to individualized disease-related risk estimations. However, they have not been validated yet in other study populations.

Available prognostic models for risk stratification of diffuse large B cell lymphoma patients: a systematic review

The International Prognostic Index (IPI) has been used for risk stratification for a long time in diffuse large B cell lymphoma (DLBCL). Based on new clinical and biological prognostic markers, many new prognostic models have been described. This review aims to present the progress in development and validation of these prognostic models. A comprehensive literature review was performed to identify studies that proposed a new prognostic model in DLBCL. A total of 38 studies met the inclusion criteria. The IPI, revised IPI (R-IPI), and National Comprehensive Cancer Network (NCCN)-IPI were the most studied prognostic indexes, externally validated and commonly used to compare to other models. Despite an increasing number of prognostic models have been proposed lately, most of them lack external validation. Further studies, that combine biological and clinical markers with prognostic significance, are needed to determine the optimal prognostic tool for more personalized treatment approach to DLBCL patients.

Venous thromboembolic events in lymphoma patients: Actual relationships between epidemiology, mechanisms, clinical profile and treatment

Venous thromboembolic events (VTE) are an underestimated health problem in patients with lymphoma. Many factors contribute to the pathogenesis of thromboembolism and the interplay between various mechanisms that provoke VTE is still poorly understood. The identification of parameters that are associated with an increased risk of VTE in lymphoma patients led to the creation of several risk-assessment models. The models that evaluate potential VTE risk in lymphoma patients in particular are quite limited, and have to be validated in larger study populations. Furthermore, the VTE prophylaxis in lymphoma patients is largely underused, despite the incidence of VTE. The lack of adequate guidelines for the prophylaxis and treatment of VTE in lymphoma patients, together with a cautious approach due to an increased risk of bleeding, demands great efforts to ensure the implementation of current knowledge in order to reduce the incidence and complications of VTE in lymphoma patients.

Development and validation of multivariable predictive model for thromboembolic events in lymphoma patients

Lymphoma patients are at increased risk of thromboembolic events but thromboprophylaxis in these patients is largely underused. We sought to develop and validate a simple model, based on individual clinical and laboratory patient characteristics that would designate lymphoma patients at risk for thromboembolic event. The study population included 1,820 lymphoma patients who were treated in the Lymphoma Departments at the Clinics of Hematology, Clinical Center of Serbia and Clinical Center Kragujevac. The model was developed using data from a derivation cohort (n = 1,236), and further assessed in the validation cohort (n = 584). Sixty-five patients (5.3%) in the derivation cohort and 34 (5.8%) patients in the validation cohort developed thromboembolic events. The variables independently associated with risk for thromboembolism were: previous venous and/or arterial events, mediastinal involvement, BMI>30 kg/m(2) , reduced mobility, extranodal localization, development of neutropenia and hemoglobin level < 100g/L. Based on the risk model score, the population was divided into the following risk categories: low (score 0-1), intermediate (score 2-3), and high (score >3). For patients classified at risk (intermediate and high-risk scores), the model produced negative predictive value of 98.5%, positive predictive value of 25.1%, sensitivity of 75.4%, and specificity of 87.5%. A high-risk score had positive predictive value of 65.2%. The diagnostic performance measures retained similar values in the validation cohort. Developed prognostic Thrombosis Lymphoma - ThroLy score is more specific for lymphoma patients than any other available score targeting thrombosis in cancer patients. Am. J. Hematol. 91:1014-1019, 2016. © 2016 Wiley Periodicals, Inc.

Gene Mutation Profiles in Primary Diffuse Large B Cell Lymphoma of Central Nervous System: Next Generation Sequencing Analyses

The existence of a potential primary central nervous system lymphoma-specific genomic signature that differs from the systemic form of diffuse large B cell lymphoma (DLBCL) has been suggested, but is still controversial. We investigated 19 patients with primary DLBCL of central nervous system (DLBCL CNS) using the TruSeq Amplicon Cancer Panel (TSACP) for 48 cancer-related genes. Next generation sequencing (NGS) analyses have revealed that over 80% of potentially protein-changing mutations were located in eight genes (CTNNB1, PIK3CA, PTEN, ATM, KRAS, PTPN11, TP53 and JAK3), pointing to the potential role of these genes in lymphomagenesis. TP53 was the only gene harboring mutations in all 19 patients. In addition, the presence of mutated TP53 and ATM genes correlated with a higher total number of mutations in other analyzed genes. Furthermore, the presence of mutated ATM correlated with poorer event-free survival (EFS) (p = 0.036). The presence of the mutated SMO gene correlated with earlier disease relapse (p = 0.023), inferior event-free survival (p = 0.011) and overall survival (OS) (p = 0.017), while mutations in the PTEN gene were associated with inferior OS (p = 0.048). Our findings suggest that the TP53 and ATM genes could be involved in the molecular pathophysiology of primary DLBCL CNS, whereas mutations in the PTEN and SMO genes could affect survival regardless of the initial treatment approach.

OC-07 - Decoding risk for thromboembolic events in lymphoma patients

INTRODUCTION

There are few prediction tools for estimating the risk of thrombosis but they are based on studies performed on hospitalized medical patients without cancer or on hospitalized neutropenic cancer patients without special consideration to lymphoma patients.

AIM

Aim of our study was to determine incidence of thromboembolic (TE) events in patients with non Hodgkin lymphoma (NHL), Hodgkin lymphoma (HL) and chronic lymphocytic leukemia (CLL)/ small lymphocytic lymphoma (SLL) who were hospitalized to the lymphoma department in the Clinic of hematology, Clinical Center Serbia, Belgrade and Clinic of hematology, Clinical Center Kragujevac. Also, we assessed 2 predictive models (Padua and Khorana score) and create new model for the identification of lymphoma patients at risk for thromboembolism.

MATERIALS AND METHODS

We reviewed all medical records of patients with with NHL, HL and CLL/SLL diagnosed and treated at two previously mentioned institution between January 2006 and December 2014.

RESULTS

The study population included 1820 eligible lymphoma patients. Of all the patients included in the study, 99 (5.4%) developed at least one TE during a follow-up period of 3 months from the end of therapy. In the final multivariate analysis, the following variables were independently associated with risk of TE: previous VTE and/or arterial events, reduced mobility (ECOG 2-4), obesity (BMI >30 kg/m(2)), extranodal localization, mediastinum involvement, development of neutropenia during therapy and hemoglobin level less than 100g/L. Subsequently, we assigned points for the risk model based on the regression coefficients obtained from the final model and developed Thrombosis Lymphoma (ThroLy) score consisting of all significant variables from the multivariate analysis. The Throly score was arrived at by assigning 2 points for all parameters with an OR >5 in multivariate regression analyses (e.g., previous VTE and arterial events, mediastinum involvement, and BMI) and 1 point for rest all other significant variables. Finally, population were divided into 3 risk categories for TE based on the score from the risk model: low (score 0-1), intermediate (score 2-3) and high (score >3). High risk score had a positive predictive value (probability of TE in those designated high risk) of 65.2%.

CONCLUSIONS

Significance of our investigation is development of score that help phisicians to recruit lymphoma patients at risk for development of thromboembolic complications. Also, we can say that our score is dynamic allowing us to change approach during different phase of therapy and is not limited to outpatient settings or with some complicated laboratory analysis.

The possible benefit from total tumour resection in primary diffuse large B-cell lymphoma of central nervous system - a one-decade single-centre experience

BACKGROUND AND METHODS

The aim of the study was to evaluate retrospectively clinical course of 27 patients with primary central nervous system lymphoma (PCNSL) diagnosed and treated by different surgical approaches. Initial therapy-diagnostic approach included surgery with total tumour reduction (TTR) performed in 12 patients (44.4%), while partial reduction and biopsy were performed in 8 (29.7%) and 7 (25.9%) patients, respectively. All patients were treated with chemotherapy based on high-dose methotrexate (HD-MTX) with/without whole-brain radiotherapy (WBRT).

RESULTS

The median overall survival (OS) and event-free survival were 37 and 31 months, respectively, with overall response rate of 74%. The patients who underwent an open surgery with TTR had significantly longer OS (median not reached), comparing with partial tumour reduction or biopsy only (Log-Rank χ(2) 6.08, p = 0.014) when median OS was 23 months. In patients with performance status according to Eastern Cooperative Oncology Group (ECOG PS) ≥ 3, OS was 23 months, contrary to ECOG PS 1-2 when median was not reached. The International Extranodal Lymphoma Study Group score (low, intermediate and high) also influenced OS between three risk groups (Log-Rank χ(2) 12.5, p = 0.002).

CONCLUSION

The treatment of PCNSL still remains doubtful, however possible benefit from the TTR followed with HD-MTX with/without WBRT should be reconsidered.

Enhanced International Prognostic Index (NCCN-IPI), Charlson Comorbidity Index and absolute lymphocyte count as predictors for survival of elderly patients with diffuse large B cell lymphoma treated by immunochemotherapy

Diffuse large B cell lymphoma (DLBCL) affects more commonly patients over 60 years. These patients have vast number of comorbidities which can modify survival as well as other clinical parameters. The aim of this study was to evaluate prognostic significance of the National Comprehensive Cancer Network International Prognostic Index (NCCN-IPI), absolute lymphocyte count (ALC), absolute monocyte count (AMC), lymphocyte-to-monocyte ratio (LMR) and comorbidities expressed with Charlson Comorbidity Index (CCI). A total of 182 DLBCL patients 60 years old and older were included, focusing on whole group and patients older than 70. All patients were treated with immunochemotherapy.Overall treatment response was achieved in 84.6% of patients. The NCCN-IPI was of highly prognostic value in the analyzed group (p<0.0001). Survival analysis showed that ALC>1.1x109/L, AMC≤0.59x109/L, and LMR>2.8 were associated with more favorable outcome (p=0.029, p=0.019, p=0.028, respectively). The patients with CCI≥2 had poorer outcome (p=0.008) compared to the patients with CCI 0-1. Multivariate analysis showed that among ALC, AMC, LMR, NCCN-IPI and CCI, the NCCN-IPI was the critical parameter that significantly affected survival (p<0.0001). Furthermore, comorbidities were also valuable independent factors which influenced survival (p=0.031) as well as the ALC (p=0.024). In elderly DLBCL patients, NCCN-IPI and ALC proved their prognostic validity, while poorer outcome could be expected in older patients with high CCI (≥2). Furthermore, mentioned prognostic parameters retained their prognostic value in the group of patients older than 70.

Single-center experience in the treatment of primary testicular lymphoma

BACKGROUND

Primary testicular lymphoma (PTL) is a rare and highly aggressive extranodal non-Hodgkin's lymphoma.

PATIENTS AND METHODS

We evaluated the clinical and histopathological features and outcomes of 10 PTL patients treated in the period of 2003-2013 with multimodal therapy (rituximab, CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone), intrathecal prophylaxis, irradiation of the contralateral testis) following orchiectomy.

RESULTS

Complete remission was achieved in 8 patients after first-line therapy while 2 patients had disease progression. The median follow-up duration was 30 months (range 6-110 months). Relapse occurred in 3 patients. 1 patient relapsed in the contralateral testis, while the other 2 patients relapsed to the skin and the central nervous system (CNS), respectively. The time to relapse was 2, 8, and 9 months. Patients with disease progression and relapse received ESHAP (etoposide, methylprednisolone, cytarabine, and cisplatin) as salvage treatment, except for 1 patient who was treated with palliative radiotherapy. After second-line therapy, only 1 patient had a short partial remission of 2 months. The median overall survival was 48 months, and the mean progression-free survival was 36 months (the median was not reached).

CONCLUSIONS

We evaluated 10 patients with PTL treated with rituximab plus CHOP, prophylactic intrathecal chemotherapy, and prophylactic irradiation of the contralateral testis, resulting in good outcome and low incidence of relapse in the contralateral testis; however, the benefit of intrathecal chemotherapy is not yet confirmed.