Novel prognostic index based on hemoglobin level and platelet count for diffuse large B-cell lymphoma, not otherwise specified in the R-CHOP era

Challenges identifying DLBCL patients with poor outcomes to upfront chemoimmunotherapy and its impact on frontline clinical trials

Diffuse large B cell lymphoma (DLBCL) has a variable course of disease among patients as it consists of subgroups that are clinically, biologically and molecularly heterogeneous. In this review, we will discuss how this heterogeneity has likely hindered the ability of traditional prognostic models to identify DLBCL patients at high risk of having poor outcomes with conventional upfront chemoimmunotherapy. We will highlight the challenges and downsides of using these models for risk stratification in clinical trials. Also, we present some of the novel prognosticators that have shown a prognostic value independently or when incorporated into existing prognostic models. Additionally, since the failure of frontline clinical trials to improve outcomes beyond R-CHOP chemoimmunotherapy may be at least partially explained by the restrictive eligibility criteria, risk stratification methods and the selection bias encountered due to the complexed logistics of clinical trials; we will discuss strategies to refine and modernize clinical trial design.

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.

Association of Laparoscopic Approach With Improved Short-Term Outcomes in Patients With Hematologic Malignancy Undergoing Splenectomy

BACKGROUND

Patients with hematologic malignancies undergo splenectomy for both diagnostic and therapeutic purposes. Although minimally invasive surgery continues to be increasingly utilized for a variety of abdominal operations, no large-scale data has compared the postoperative outcomes for laparoscopic vs open splenectomy in patients with hematologic malignancy.

METHODS

Patients with a diagnosis of hematologic malignancy who underwent laparoscopic and open splenectomy between 2015 and 2020 were queried using the ACS-NSQIP database. 30-day outcomes of laparoscopic vs open splenectomy were compared.

RESULTS

Out of 430 patients included in the study, 52.6% were male, with a mean age of 63.4 ± 13.1 years. 233 patients (54.2%) underwent laparoscopic splenectomy. On bivariate analysis, laparoscopic surgery was associated with lower rates of 30-day mortality [2.1% vs 11.7% (P < .001)] and morbidity [9.0% vs 24.4% (P < .001)]. On multivariate regression, elective operations (OR .255, 95%CI: 0.084-.778, P = .016) and laparoscopic surgery (OR .239, 95%CI: 0.075-.760, P = .015) were independently associated with lower mortality, while history of metastatic cancer (OR 3.331, 95%CI: 1.144-9.699, P = .027) was associated with higher mortality. Laparoscopic surgery (OR .401, 95%CI: 0.209-.770, P = .006) and steroid use (OR 2.714, 95%CI: 1.279-5.757, P = .009) were the only two factors independently associated with 30-day morbidity. Laparoscopic surgery was also associated with shorter hospital length of stay (median 3 [IQR:3] vs 6 [IQR:7] days).

CONCLUSION

Laparoscopic splenectomy was associated with lower 30-day mortality and morbidity, and shorter length of stay in patients with hematologic malignancies. These data suggest that laparoscopic approach, when feasible, may be preferred for splenectomy in this patient population.

Enhancement of the International prognostic index with β2-microglobulin, platelet count and red blood cell distribution width: a new prognostic model for diffuse large B-cell lymphoma in the rituximab era

Background

This study aimed to propose a new user-friendly, cost effective and robust risk model to facilitate risk stratification for diffuse large B-cell lymphoma (DLBCL) treated with frontline R-CHOP regimens.

Methods

Data on 998 patients with de novo DLBCL diagnosed between Jan 1st, 2005 and Dec 31st, 2018 at our center, who received frontline R-CHOP or R-CHOP-like regimens, were retrospectively collected. Patients were randomly divided into the training cohort (n = 701) and the validation cohort (n = 297). A new prognostic model for overall survival (OS) was built based on the training cohort. The performance of the new model was compared with International prognostic index (IPI), revised IPI (R-IPI) and National Comprehensive Cancer Network (NCCN)-IPI (NCCN-IPI). The new model was validated in the validation cohort.

Results

The multivariate analysis of the training cohort showed that the IPI, β2-microglobulin, platelet count and red blood cell distribution width were independent factors for OS, which were incorporated into the new prognostic model. Patients were stratified into low risk, low-intermediate risk, high-intermediate risk, high risk and very high risk groups, with distinct survival outcomes. The new model achieved good C-indexes for 5-year OS prediction of 0.750 (95%CI 0.719–0.781) and 0.733 (95%CI 0.682–0.784) in the training and validation cohorts, respectively, and displayed well-fitted calibration curves. The C-index and the time-dependent ROC analysis demonstrated better performance of the new model than the IPI, R-IPI and NCCN-IPI in both training and validation cohorts. The integrated Brier score for predicting 5-year OS of the new model was lower than that of the IPI, R-IPI and NCCN-IPI in both cohorts, and decision curve analysis also showed a higher net benefit, indicating the superiority of the new model over the conventional models.

Conclusion

The new prognostic model might be a useful predictive tool for DLBCL treated with R-CHOP regimens. Further external validation is warranted.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09693-z.

Novel prognostic predictor of haemoglobin-platelet index in diffuse large B-cell lymphoma, not otherwise specified: Anaemia and thrombocytopenia are associated with IL-6 production in lymphoma cells

We previously reported that a novel haemoglobin-platelet index (HPI) based on anaemia and thrombocytopenia was useful to predict the prognosis of patients with diffuse large B-cell lymphoma not otherwise specified (DLBCL NOS). Here, we analyse the utility of HPI in a new validation cohort with DLBCL NOS (n  = 94). As a result, we confirm that HPI was effective for differentiating progression-free survival (PFS) and overall survival in this validation cohort. So, we further compare the utility of HPI with previously reported prognostic markers such as the National Comprehensive Center Network-International Prognostic Index (NCCN-IPI), Glasgow prognostic score (GPS), and platelet-albumin (PA) score, using a larger number of 160 patients consisting of the derivation cohort (n  = 66) and a validation cohort (n  = 94). As a result, the patients with a higher HPI score had significantly worse outcomes, and HPI predicted the prognosis of DLBCL NOS independently of NCCN-IPI. HPI was more sensitive than GPS and almost the same as PA score in predicting PFS. Moreover, the patients whose lymphoma cells were positive for interleukin-6 (IL-6) (75/111 cases) judged by immunohistochemical staining had significantly lower haemoglobin levels and platelet counts than IL-6-negative cases (36/111 cases), suggesting the involvement of IL-6 produced by lymphoma cells in anaemia and thrombocytopenia in DLBCL NOS patients.

The pretreatment platelet count predicts survival outcomes of diffuse large B-cell lymphoma: An analysis of 1007 patients in the rituximab era

BACKGROUND

The prognostic value of platelet count in diffuse large B-cell lymphoma (DLBCL) has not been extensively investigated. We aimed to examine the association of pretreatment platelet count with disease features, and further examine the prognostic significance of platelet count in DLBCL treated with the R-CHOP regimen.

METHODS

Patients with DLBCL diagnosed between Jan 1 st, 2005 and Dec 31 st, 2018 at Cancer Hospital, Chinese Academy of Medical Sciences were retrospectively analyzed. Propensity score matching (PSM) was used to balance confounding factors.

RESULTS

A total of 1007 eligible patients who received frontline R-CHOP or R-CHOP-like regimens were included in this study. The optimal cutoff value of platelet count was 157 × 10⁹/L, as determined by the Maximally Selected Rank Statistics method. Patients with the platelet count ≤157 × 10⁹/L had significantly inferior overall survival (OS) (5-year OS, 44.4 % vs. 74.9 %, P < 0.001) and progression-free survival (PFS) (5-year PFS, 35.5 % vs. 65.9 %, P < 0.001) than those with the platelet count >157×10⁹/L. Multivariate analyses showed that pretreatment platelet count ≤ 157 × 10⁹/L was an adversely independent prognostic factor for OS (hazard ratio [HR] 1.960, 95 % confidence interval [CI] 1.418-2.709, P<0.001) and PFS (HR 1.443, 95 %CI 1.080-1.927, P = 0.013). The PSM analysis and subgroup analyses further confirmed the significantly negative impact of low platelet count on OS and PFS.

CONCLUSION

The pretreatment platelet count may be a simple, cost-effective and useful prognostic factor in DLBCL patients treated with frontline R-CHOP regimens. Further investigation is warranted to elucidate the biologic mechanism underlying the prognostic significance of platelet count in DLBCL.

Low platelet/platelet distribution width and high platelet/lymphocyte ratio are adverse prognostic factors in patients with newly diagnosed advanced Hodgkin lymphoma

We conducted a retrospective study in 274 previously untreated advanced Hodgkin lymphoma (HL) patients to investigate the prognostic value of baseline platelet (PLT) count, platelet distribution width (PDW), mean platelet volume (MPV), and platelet/lymphocyte ratio (PLR). The median follow-up time was 89 (range 0.3-240) months. By univariate analysis, PLT/PDW <24.5, PLR ≥245, and MPV <8fl were all associated with worse freedom from progression (FFP), progression-free survival (PFS), and overall survival (OS). By multivariate analysis, PLT/PDW <24.5 was a risk factor for FFP (HR 2.02, p = 0.002) and PFS (HR 2.36, p < 0.001). PLR ≥245 was independently associated with inferior FFP (HR 2.04, p = 0.003) and PFS (HR 1.93, p = 0.002). Due to the limited number of death events, multivariate analysis was not conducted for OS. Propensity score matching analysis and subgroup analysis further validated the prognostic value for PLT/PDW and PLR. In conclusion, PLT/PDW and PLR are promising prognostic indicators for newly diagnosed advanced HL.

Resolution of Chronic Immune Thrombocytopenia Purpura after Autologous Hematopoietic Stem Cell Transplantation for Diffuse Large B-Cell Lymphoma

Immune thrombocytopenic purpura (ITP) is a hematological disorder characterized by immune-mediated destruction of platelets that could be triggered by a number of causes. ITPs are usually treated with steroid, immunomodulators or immunosuppressors, and intravenous immunoglobulin therapy though refractory/relapsed status frequently occurs. It was suggested that autologous hematopoietic stem cell transplant (HSCT) after high-dose chemotherapy conditioning might improve ITP patients’ peripheral blood platelet counts via reorganizing disrupted immune balance in the hematopoietic and hematologic systems. In this case report, we describe how a patient, who suffered from both severe thrombocytopenia due to chronic ITP and refractory/relapsed diffuse large B-cell lymphoma (DLBCL), was managed to successfully receive autologous HSCT using carmustine, etoposide, cytarabine and melphalan (BEAM) conditioning regimens and how his chronic ITP was eventually cured after receiving autologous HSCT. This is the first clinical case in the world demonstrating that high-dose BEAM chemotherapy conditioned autologous HSCT could cure chronic ITP while successfully managing refractory/relapse DLBCL. The clinical hematology professionals and the patients will benefit from our experience in managing severe thrombocytopenia while conducting high-dose chemotherapy conditioning and autologous HSCT for DLBCL.

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.

Risk Stratification Using Multivariable Fractional Polynomials in Diffuse Large B-Cell Lymphoma

The risk stratification of diffuse large B-cell lymphoma (DLBCL) is crucial. The International Prognostic Index, the most commonly used and the traditional risk stratification system, is composed of fixed and artificially dichotomized attributes. We aimed to develop a novel prognostic model that allows the incorporation of up-to-date attributes comprehensively without information loss. We analyzed 204 patients with primary DLBCL who were uniformly treated with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) from 2007 to 2012 at Asan Medical Center. Using the multivariable fractional polynomial (MFP) method and bootstrap resampling, we selected the variables of significance and the best fitted functional form in fractional polynomials. Age, serum β2-microglobulin, serum lactate dehydrogenase, and BCL2 expression were selected as significant variables in predicting overall survival (OS), while age was excluded in predicting 2-years event-free survival. The prognostic score calculated by the MFP model effectively classifies patients into four risk groups with 5-years OS of 89.91% (low risk), 81.21% (low-intermediate risk), 66.40% (high-intermediate risk), and 37.89% (high risk). We suggest a new prognostic model that is simple and flexible. By using the MFP method, we can incorporate various clinicopathologic factors into a risk stratification system without arbitrary dichotomization.

Red blood cell distribution width and platelet counts are independent prognostic factors and improve the predictive ability of IPI score in diffuse large B-cell lymphoma patients

Background

Elevated red blood cell distribution width (RDW) and decreased platelet count (PLT) can be clinically relevant to the prognosis in cancer patients. However, their prognostic values in patients with diffuse large B-cell lymphoma (DLBCL) need to be further explored.

Methods

Healthy donors (n = 130) and patients with DLBCL (n = 349) were included and evaluated retrospectively in this study. The prognostic influence of clinical and pathological factors including RDW and PLT on overall survival (OS) and progression-free survival (PFS) were studied by Kaplan-Meier curves. To evaluate the independent prognostic relevance of RDW and PLT, univariate and multivariate Cox proportional hazards regression models were applied. The adjusted IPI model was established based on the results of multivariate analysis, and verified by Harrell’s C statistical analysis.

Results

Kaplan-Meier curves indicated that an elevated RDW value and thrombocytopenia are poor factors for OS (P < 0.001, P = 0.006) and PFS (P = 0.003, P < 0.001) in DLBCL patients. Multivariate analysis confirmed that elevated RDW value (HR = 2.026, 95%CI = 1.263–3.250, P = 0.003) and decreased PLT count (HR =1.749, 95%CI = 1.010–3.028, P = 0.046) were both independent prognostic factors. The c-index of IPI and NCCN-IPI were increased when RDW level and PLT were supplemented in our cohort.

Conclusions

Our study shows that elevated RDW level and decreased PLT are independent poor prognostic factors in newly diagnosed DLBCL patients. Adding RDW and PLT to the IPI score may improve its predictive ability, and the adjusted IPI may be more powerful in predicting the survival of DLBCL patients in the rituximab era.