Assessment of the hematopoietic cell transplantation comorbidity index in non-Hodgkin lymphoma patients receiving reduced-intensity allogeneic hematopoietic stem cell transplantation

Allogeneic stem cell transplantation as a curative option in relapse/refractory diffuse large B cell lymphoma: Spanish multicenter GETH/GELTAMO study

We performed a retrospective multicenter study including 140 patients with relapsed/refractory (R/R) diffuse large B cell lymphoma (DLBCL) who underwent allogeneic hematopoietic stem cell transplantation (allo-SCT) from March 1995 to November 2018. Our objective was to analyze long term outcomes. Seventy-four percent had received a previous auto-SCT (ASCT) and the median number of lines pre-allo-SCT was 3 (range 1-9). Three year-event free survival (EFS) and overall survival (OS) were 38% and 44%, respectively. Non-relapse mortality (NRM) at day 100 was 19%. Cumulative incidence of grade III-IV acute graft versus host disease (GVHD) at day 100 was 16% and moderate/severe chronic GVHD at 3 years 34%. Active disease at allo-SCT (HR 1.95, p = 0.039) (HR 2.19, p = 0.019), HCT-CI ≥ 2 (2.45, p = 0.002) (HR 2.33, p = 0.006) and donor age >37 years (HR 2.75, p = 0.014) (HR 1.98, p = 0.043) were the only independent variables both for PFS and OS, respectively. NRM was significantly modified by HCT-CI ≥ 2 (HR 4.8, p = 0.008), previous ASCT (HR 4.4, p = 0.048) and grade III-IV acute GVHD on day 100 (HR 6.13, p = 0.016). Our data confirmed that allo-SCT is a curative option for patients with R/R DLBCL, displaying adequate results for fit patients with chemosensitive disease receiving an allo-SCT from a young donor.

Prognostic Scoring Systems in Allogeneic Hematopoietic Stem Cell Transplantation: Where Do We Stand?

Allogeneic hematopoietic stem cell transplantation is a potentially curative treatment for many hematologic disorders. Maximizing the benefit of transplantation for disease control while minimizing the risk for associated complications remains the field's leading challenge. This challenge has prompted the development of multiple prognostic scoring systems over the last 2 decades. Prognostic scores can be used for informed decision making, better patient counseling, design of interventional trials, and analysis of prospective and retrospective data. They are also helpful in treatment allocation and personalization according to predicted risk. A better understanding of the molecular and cytogenetic features of the disease, along with the advent of novel therapies, has increased the need for reliable prognostication of which patients will benefit most from transplantation. Here we review the clinical role of the prognostic systems currently in clinical use, examining both their strengths and their limitations.

Impact of Pretransplantation Indices in Hematopoietic Stem Cell Transplantation: Knowledge of Center-Specific Outcome Data Is Pivotal before Making Index-Based Decisions

Outcome after allogeneic hematopoietic stem cell transplantation is influenced by patient comorbidity, disease type, and status before treatment. We performed a retrospective study involving 521 consecutive adult hematopoietic stem cell transplantation patients who underwent transplantation for hematological malignancy at our center from 2000 to 2012 to compare the predictive value of the hematopoietic cell transplantation-specific comorbidity index (HCT-CI) and the disease risk index (DRI) for overall survival and transplantation-related mortality. Patients in the highest HCT-CI risk group (HCT-CI score ≥3) had a lower 5-year overall survival rate (50%) than the low-risk group (63%; P < .01). Subset analysis of donor origin showed greater 5-year overall survival in siblings than in matched unrelated donors, regardless of HCT-CI score (eg, 67% 5-year overall survival in siblings despite an HCT-CI score of >6 [n = 9]). Five-year overall survival in the highest DRI risk group was significantly poorer (44%) than in the low-risk group (63%; P < .01). Both indices failed to predict differences in transplantation-related mortality (HCT-CI, P = .54; DRI, P = .17). We conclude that HCT-CI and DRI were predictive of overall survival in our patient population. Even so, our data show that different patient groups may have different outcomes despite sharing the same index risk group and that indices should, therefore, be evaluated according to local data before clinical implementation at the single-center level.

Hematopoietic Cell Transplantation Comorbidity Index Predicts Outcomes in Patients with Acute Myeloid Leukemia and Myelodysplastic Syndromes Receiving CD34+ Selected Grafts for Allogeneic Hematopoietic Cell Transplantation

To evaluate the association between the hematopoietic cell transplantation-comorbidity index (HCT-CI) and the recently developed age-adjusted HCT-CI (HCT-CI/age) and transplant outcomes in the setting of CD34-selected allogeneic HCT, we analyzed a homogeneous population of patients undergoing allogeneic HCT with CD34-selected grafts for acute myeloid leukemia and myelodysplastic syndrome (n = 346). Median HCT-CI and HCT-CI/age scores were 2 (percentile 25 to 75, 1 to 4) and 3 (percentile 25 to 75, 1 to 5), respectively. Higher HCT-CI and HCT-CI/age scores were associated with higher nonrelapse mortality (NRM) and lower overall survival (OS). The HCT-CI distinguished 2 risk groups (0 to 2 versus ≥3), whereas, with the HCT-CI/age, there was a progressive increase in NRM and decrease in OS with increasing scores in all 4 groups (0 versus 1 to 2 versus 3 to 4 versus ≥5). Higher scores in both models were associated with lower chronic graft-versus-host disease relapse-free survival but not with higher relapse. Both models showed a promising predictive accuracy for NRM (c- = .616 for HCT-CI and c- = .647 for HCT-CI/age). In conclusion, the HCT-CI and HCT-CI/age predict transplant outcomes in CD34-selected allo-HCT, including NRM, OS, and chronic graft-versus-host disease relapse-free survival and may be used to select appropriate patients for this approach.

Comorbidities, Alcohol Use Disorder, and Age Predict Outcomes after Autologous Hematopoietic Cell Transplantation for Lymphoma

Autologous hematopoietic cell transplantation (HCT) is a treatment option for many patients diagnosed with lymphoma. The effects of patient-specific factors on outcomes after autologous HCT are not well characterized. Here, we studied a sequential cohort of 754 patients with lymphoma treated with autologous HCT between 2000 and 2010. In multivariate analysis, patient-specific factors that were statistically significantly associated with nonrelapse mortality (NRM) included HCT-specific comorbidity index (HCT-CI) scores  ≥ 3 (HR, 1.94; P = .05), a history of alcohol use disorder (AUD) (HR, 2.17; P = .004), and older age stratified by decade (HR, 1.29; P = .02). HCT-CI ≥ 3, a history of AUD, and age > 50 were combined into a composite risk model: NRM and overall mortality rates at 5 years increased from 6% to 30% and 32% to 58%, respectively, in patients with 0 versus all 3 risk factors. The HCT-CI is a valid tool in predicting mortality risks after autologous HCT for lymphoma. AUD and older age exert independent prognostic impact on outcomes. Whether AUD indicates additional organ dysfunction or sociobehavioral abnormality warrants further investigation. The composite model may improve risk stratification before autologous HCT.

Prediction of non-relapse mortality in recipients of reduced intensity conditioning allogeneic stem cell transplantation with AML in first complete remission

Non-relapse mortality (NRM) after allogeneic hematopoietic stem cell transplantation (alloHSCT) can be predicted by the hematopoietic cell transplantation comorbidity index (HCT-CI) and the European Group for Blood and Marrow Transplantation (EBMT) score, which are composed of different parameters. We set out to integrate the parameters of both scores in patients with acute myeloid leukemia (AML) in first complete remission (CR1) receiving reduced intensity conditioning (RIC) alloHSCT. All parameters from the HCT-CI and the EBMT-score with the addition of patient and donor cytomegalovirus serology were evaluated in 812 patients by multivariable analysis with end-point NRM at 2 years. Subsequently, 16 parameters were selected based on hazard ratio >1.2, and were incorporated into a novel score, which was further internally validated by bootstrapping. Both the HCT-CI and the EBMT-score showed relatively weak predictive value, whereas the integrated score allowed to identify three clearly distinct risk groups with 2-year NRM estimates of 8±2% (low-risk), 17±2% (intermediate-risk) and 38±4% (high-risk), which also translated in prediction of overall survival. Collectively, integration of the most dominant parameters from the HCT-CI and the EBMT-score allowed to develop a simple and robust, integrated score with improved prediction of NRM for AML patients proceeding to RIC alloHSCT in CR1.

A prospective study of an alemtuzumab containing reduced-intensity allogeneic stem cell transplant program in patients with poor-risk and advanced lymphoid malignancies

Reduced-intensity conditioning (RIC) regimens for allogeneic stem cell transplant (allo-SCT) have used alemtuzumab to abrogate the risk of graft-versus-host disease (GVHD). Thirty-eight patients with advanced lymphoma underwent a prospective phase II study of melphalan, fludarabine and alemtuzumab containing RIC allo-SCT from 20 matched related and 18 unrelated donors with cyclosporine-A as GVHD prophylaxis. The cumulative incidence of grade II-IV acute GVHD at 3 months was 10.5% and three evaluable patients experienced chronic GVHD. Progression-free (PFS) and overall (OS) survival at 5 years was 25% (95% confidence interval [CI]: 13-40%) and 44% (95% CI: 28-59%), respectively. Previous high-dose therapy and autologous stem cell transplant (HDT-ASCT) and elevated lactate dehydrogenase (LDH) at the time of allo-SCT resulted in inferior OS. Within this cohort of patients with high-risk lymphoma, alemtuzumab containing RIC resulted in a low risk of GVHD and a high incidence of progression of disease, especially in those with poor-risk features defined by elevated LDH pre-allo-SCT and previous HDT-ASCT.

Hematopoietic cell transplant comorbidity index is predictive of survival after autologous hematopoietic cell transplantation in multiple myeloma

Autologous hematopoietic stem cell transplantation (AHCT) improves survival in patients with multiple myeloma (MM) but is associated with morbidity and nonrelapse mortality (NRM). Hematopoietic cell transplant comorbidity index (HCT-CI) was shown to predict risk of NRM and survival after allogeneic transplantation. We tested the utility of HCT-CI as a predictor of NRM and survival in patients with MM undergoing AHCT. We analyzed outcomes of 1156 patients of AHCT after high-dose melphalan reported to the Center for International Blood and Marrow Transplant Research. Individual comorbidities were prospectively collected at the time of AHCT. The impact of HCT-CI and other potential prognostic factors, including Karnofsky performance score (KPS), on NRM and survival were studied in multivariate Cox regression models. HCT-CI score was 0, 1, 2, 3, and >3 in 42%, 18%, 13%, 13%, and 14% of the study cohort, respectively. Subjects were stratified into 3 risk groups: HCT-CI score of 0 (42%) versus HCT-CI score of 1 to 2 (32%) versus HCT-CI score > 2 (26%). Higher HCT-CI was associated with lower KPS < 90 (33% of subjects score of 0 versus 50% in HCT-CI score > 2). HCT-CI score > 2 was associated with melphalan dose reduction (22% versus 10% in score 0 cohort). One-year NRM was low at 2% (95% confidence interval, 1% to 4%) and did not correlate with HCT-CI score (P = .9). On multivariate analysis, overall survival was inferior in groups with HCT-CI score of 1 to 2 (relative risk, 1.37, [95% confidence interval, 1.01 to 1.87], P = .04) and HCT-CI score > 2 (relative risk, 1.5 [95% confidence interval, 1.09 to 2.08], P = .01). Overall survival was also inferior with KPS < 90 (P < .001), IgA subtype (P ≤ .001), those receiving >1 pretransplant induction regimen (P = .007), and those with resistant disease at the time of AHCT (P < .001). AHCT for MM is associated with low NRM, and death is predominantly related to disease progression. Although a higher HCT-CI score did not predict NRM, it was associated with inferior survival.

Hematopoietic cell transplantation-specific comorbidity index predicts inpatient mortality and survival in patients who received allogeneic transplantation admitted to the intensive care unit

PURPOSE

To investigate the prognostic value of the Hematopoietic Cell Transplantation-Specific Comorbidity Index (HCT-CI) in patients who received transplantation admitted to the intensive care unit (ICU).

PATIENTS AND METHODS

We investigated the association of HCT-CI with inpatient mortality and overall survival (OS) among 377 patients who were admitted to the ICU within 100 days of allogeneic stem-cell transplantation (ASCT) at our institution. HCT-CI scores were collapsed into four groups and were evaluated in univariate and multivariate analyses using logistic regression and Cox proportional hazards models.

RESULTS

The most common pretransplantation comorbidities were pulmonary and cardiac diseases, and respiratory failure was the primary reason for ICU admission. We observed a strong trend for higher inpatient mortality and shorter OS among patients with HCT-CI values ≥ 2 compared with patients with values of 0 to 1 in all patient subsets studied. Multivariate analysis showed that patients with HCT-CI values ≥ 2 had significantly higher inpatient mortality than patients with values of 0 to 1 and that HCT-CI values ≥ 4 were significantly associated with shorter OS compared with values of 0 to 1 (hazard ratio, 1.74; 95% CI, 1.23 to 2.47). The factors associated with lower inpatient mortality were ICU admission during the ASCT conditioning phase or the use of reduced-intensity conditioning regimens. The overall inpatient mortality rate was 64%, and the 1-year OS rate was 15%. Among patients with HCT-CI scores of 0 to 1, 2, 3, and ≥ 4, the 1-year OS rates were 22%, 17%, 18%, and 9%, respectively.

CONCLUSION

HCT-CI is a valuable predictor of mortality and survival in critically ill patients after ASCT.

The hematopoietic cell transplantation-specific comorbidity index (HCT-CI) is an outcome predictor for partially matched related donor transplantation

To validate the predictive ability of the Hematopoietic Cell Transplantation-Specific Comorbidity Index (HCT-CI) on the outcome of hematopoietic stem cell transplantation (HSCT) patients who received transplants from partially matched related donors (PMRD), a total of 526 patients who received PMRD HSCT between January 2006 and December 2009 at the Institute of Hematology, Peking University were enrolled. Patients were grouped according to their HCT-CI score; 31.0%, 31.4%, and 37.6% of patients had HCT-CI scores of 0, 1-2, and ≥3, respectively. Patients with HCT-CI scores of ≥3 had a significantly poorer 2-year overall survival (OS) than patients with HCT-CI scores of 0-2 (54.55% vs. 78.05%, P < 0.001). In addition, patients with HCT-CI scores of ≥3 had a significantly higher 2-year cumulative incidence of relapse and nonrelapse mortality (NRM) than patients with scores of 0-2 (relapse: 23.23% vs. 11.59%, P < 0.001; NRM: 34.30% vs. 15.93%, P < 0.001). HCT-CI scores of <3 were associated with better OS, less relapse, and lower NRM in multivariate analysis. Patients who had high comorbidity scores as well as high-risk disease had the poorest outcomes. Therefore, we found that HCT-CI is associated with the outcomes of PMRD HSCT and we should closely monitor patients with a high comorbidity burden.

Comorbidity burden in patients with chronic GVHD

Chronic GVHD (cGVHD) is associated with mortality, disability and impaired quality of life. Understanding the role of comorbidity in patients with cGVHD is important both for prognostication and potentially for tailoring treatments based on mortality risks. In a prospective cohort study of patients with cGVHD (n=239), we examined the performance of two comorbidity scales, the Functional Comorbidity Index (FCI) and the Hematopoietic Cell Transplantation-specific Comorbidity Index (HCT-CI). Both scales detected a higher number of comorbidities at cGVHD cohort enrollment than pre-hematopoietic cell transplant (HCT) (P<0.001). Higher HCT-CI scores at the time of cGVHD cohort enrollment were associated with higher non-relapse mortality (HR: 1.21:1.04-1.42, P=0.01). For overall mortality, we detected an interaction with platelet count. Higher HCT-CI scores at enrollment were associated with an increased risk of overall mortality when the platelet count was ≤ 100,000/μL (HR: 2.01:1.20-3.35, P=0.01), but not when it was >100,000/μL (HR: 1.05:0.90-1.22, P=0.53). Comorbidity scoring may help better to predict survival outcomes in patients with cGVHD. Further studies to understand vulnerability unrelated to cGVHD activity in this patient population are needed.

Adjusting DLCO for Hb and its effects on the Hematopoietic Cell Transplantation-specific Comorbidity Index

The Hematopoietic Cell Transplantation-specific Comorbidity Index (HCT-CI) is used to counsel patients regarding the risk of transplantation and selection of conditioning regimens. Pulmonary disease, most frequently demonstrated by a decreased diffusion capacity of carbon monoxide (DLCO), is the most prevalent comorbidity captured by the HCT-CI. The HCT-CI was validated using the Dinakara method for adjusting DLCO for Hb, but our institution and others utilize the Cotes method. The purpose of this study was to determine the impact of using the Cotes method rather than the Dinakara method on the HCT-CI score. We reviewed pre-transplant pulmonary function tests in 73 patients who underwent allogeneic hematopoietic SCT. Patients were stratified into low, intermediate or high-risk groups based on HCT-CI scores of 0, 1-2 or 3, respectively. We found that compared with the Dinakara method, the Cotes method increased the HCT-CI score in 45% of patients and resulted in total HCT-CI scores predictive of higher non-relapse mortality in 33% of patients. These results indicate that if an institution uses the Cotes method to adjust DLCO for Hb, their patients may be counseled to expect a higher risk of mortality than is actually predicted by the HCT-CI, and may be excluded from transplantation. Therefore, unless the HCT-CI is validated using other methods for correcting DLCO for Hb, the Dinakara method should be used.

How I assess comorbidities before hematopoietic cell transplantation

The hematopoietic cell transplantation-comorbidity index (HCT-CI) is a comorbidity tool suited for recipients of HCT. The index has been shown to sensitively capture the prevalence and magnitude of severity of various organ impairments before HCT and to provide valuable prognostic information after HCT. Many investigators have validated the discriminative power of the HCT-CI, but others have not. One concern is the consistency in comorbidity coding across different evaluators, particularly in view of the relatively recent addition of the HCT-CI to the transplant evaluation process. In this article, comorbidity scoring was tested across different evaluators, and only a fair interobserver agreement rate could be detected. To address these issues, a brief training program is proposed here, consisting of systematic methodology for data acquisition and consistent guidelines for comorbidity coding that were summarized in a Web-based calculator. In a validation patient cohort, this training program was shown to improve the interevaluator agreement on HCT-CI scores to an excellent rate with weighted κ values in the range of 0.89 to 0.97. This proposed training program will facilitate reliable assessment of comorbidities in the clinic and for research studies leading to standardization of the use of comorbidities in prediction of HCT outcomes.

Validation of the Hematopoietic Cell Transplantation-Specific Comorbidity Index: a prospective, multicenter GITMO study

The development of tools for the prediction of nonrelapse mortality (NRM) after allogeneic hematopoietic stem cell transplantation (HSCT) would offer a major guidance in the therapeutic decision. Recently, the Hematopoietic Cell Transplantation-Specific Comorbidity Index (HCT-CI) has been associated with increased NRM risk in several retrospective studies, but its clinical utility has never been demonstrated prospectively in an adequately sized cohort. To this aim, we prospectively evaluated a consecutive cohort of 1937 patients receiving HSCT in Italy over 2 years. HCT-CI was strongly correlated with both 2-year NRM (14.7%, 21.3%, and 27.3% in patients having an HCT-CI score of 0, 1-2, and ≥ 3, respectively) and overall survival (56.4%, 54.5%, and 41.3%, respectively). There was an excellent calibration between the predicted and observed 2-year NRM in patients having an HCT-CI score of 0 and 1-2, whereas in the ≥ 3 group the predicted NRM overestimated the observed NRM (41% vs 27.3%). HCT-CI alone was the strongest predictor of NRM in patients with lymphoma, myelodysplastic syndrome, and acute myeloid leukemia in first remission (c-statistics 0.66, 064, and 0.59, respectively). We confirm the clinical utility of the HCT-CI score that could also identify patients at low NRM risk possibly benefiting from an HSCT-based treatment strategy.

Pretransplantation assessments and symptom profiles: predicting transplantation-related toxicity and improving patient-centered outcomes

With the advent of reduced-intensity conditioning regimens and improvements in supportive care, hematopoietic cell transplantation (HCT) has become increasingly available to older adults and medically vulnerable populations with hematologic diseases. However, adverse outcomes including long-term treatment-related distress, disability (frailty), and death remain important concerns in this population. In other areas of oncology, comprehensive geriatric assessments have been used to stratify patients for treatment-related risk, and patient-reported outcomes (PROs) have helped in understanding treatment-related toxicity from a patient perspective. However, these powerful tools have not yet become widely used in HCT. Here, we review the theories and available data that support the development of pretreatment functional assessments and longitudinal PRO sampling in HCT. We discuss the potential for these techniques to improve transplantation outcomes through risk stratification, interventional studies, and predictive models that incorporate genetic and biomarker data. Predicting and understanding long-term transplantation-related toxicity through functional assessments and PROs will be critical to calculating the risk/benefit ratio of aggressive therapies in older patient populations, and we contend that functional assessments and PRO sampling should become standard parts of the routine evaluation of HCT patients.

Hematopoietic cell transplantation comorbidity index predicts transplantation outcomes in pediatric patients

Quantifying the risk of hematopoietic cell transplantation (HCT)-related mortality for pediatric patients is challenging. The HCT-specific comorbidity index (HCT-CI) has been confirmed as a useful tool in adults, but has not yet been validated in children. We conducted a retrospective cohort study of 252 pediatric patients undergoing their first allogeneic HCT between January 2008 and May 2009. Pretransplantation comorbidities were scored prospectively using the HCT-CI. Median age at transplantation was 6 years (range, 0.1-20) and median follow-up was 343 days (range, 110-624). HCT-CI scores were distributed as follows: 0, n=139; 1-2, n=52; and 3+, n=61. The 1-year cumulative incidence of nonrelapse mortality (NRM) increased (10%, 14%, and 28%, respectively; P<.01) and overall survival (OS) decreased (88%, 67%, and 62%, respectively; P<.01) with increasing HCT-CI score. Multivariate analysis showed that compared with score 0, those with scores of 1-2 and 3+ had relative risks of NRM of 1.5 (95% confidence interval, 0.5-4.3, P=.48) and 4.5 (95% confidence interval, 1.7-12.1, P<.01), respectively. These results indicate that the HCT-CI score predicts NRM and OS in pediatric patients undergoing HCT and is a useful tool to assess risk, guide counseling in the pretransplantation setting, and devise innovative therapies for the highest risk groups.

Comorbidity index does not predict outcome in allogeneic myeloablative transplants conditioned with fludarabine/i.v. busulfan (FluBu4)

The assessment of a hematopoietic stem cell transplant (HSCT)-specific comorbidity index (HCT-CI) has been developed to predict the risk of TRM in patients undergoing allogeneic HSCT. As the myeloablative fludarabine/i.v. busulfan (FluBu4) regimen has been associated with limited extra-hematologic toxicity, we analyzed whether the HCT-CI represents a useful tool in transplant patients conditioned with this regimen. Of the 52 consecutive patients who received an allogeneic HSCT with FluBu4 at our institution, 50 were evaluable for assessing pre-transplant HCT-CI. Patients were divided into three groups: score 0 (n=7); score 1-2 (n=17) and score >3 (n=26). The three groups did not differ significantly in age, diagnosis, previous lines of chemotherapy and type of donor. High-risk disease was present in 57% of low, 82% of intermediate and 85% of high HCT-CI score groups (P=ns). Two-year TRM and OS was 14.3 and 85.7% in the low score group, 23.5 and 58.8% in the intermediate score group and 15.4 and 50% in the high HCT-CI score group (P=ns). In this study, the HCT-CI lacked sensitivity to reliably predict TRM although patients with no comorbidities showed a trend for improved survival.

Retrospective analysis of common scoring systems and outcome in patients older than 60 years treated with reduced-intensity conditioning regimen and alloSCT

In this retrospective study, 63 patients >60 years with hematological malignancies and treated with allo-SCT and with reduced-intensity conditioning (RIC) were reviewed. A total of 51% of patients suffered from AML or myelodysplastic syndromes. Disease status before transplantation was CR or PR 71 with 29% transplanted with active disease. Patients were classified according to three published prognostic indexes: (1) hematopoietic cell transplantation comorbidity index (HCT-CI); (2) European BMT (EBMT) score; and (3) Pretransplantation Assessment of Mortality (PAM) score. The 100-day and 1-year treatment-related mortality (TRM) were 6 and 22%, respectively, for the entire group. The 2-year OS and PFS were 60 and 58%, respectively. The incidence of grade II-IV acute GVHD (aGVHD) and extensive chronic GVHD was 46 and 48%, respectively. In a univariate analysis, neither the HCT-CI nor the EBMT score, nor the PAM score were predictive of TRM and OS. Only the occurrence of aGVHD affected the TRM and OS. ALLO-RIC is feasible in elderly patients. Even if those prognostic scores were not adapted to elderly patients, they did not predict for TRM and OS. aGVHD is the main cause of TRM and more efforts should be made to reduce its incidence without sacrificing graft vs tumor effect.

Comorbidities and hematopoietic cell transplantation outcomes

Conventional allogeneic hematopoietic cell transplantation (allo-HCT) is a potentially curative treatment option for various hematological diseases due, in part to high-dose conditioning and, in part, to graft-versus-tumor effects. Reduced-intensity or non-myeloablative conditioning regimens have relied mostly on graft-versus-tumor effects for disease control, and their advent has allowed relatively older and medically infirm patients to be offered allo-HCT. However, both HCT modalities have been associated with organ toxicities and graft-versus-host disease, resulting in substantial non-relapse mortality. It has become increasingly important to optimize pre-transplant risk assessment in order to improve HCT decision making and clinical trial assignments. Single-organ comorbidity involving liver, lung, heart, or kidney before HCT has been traditionally found to cause organ toxicity after HCT. Recent efforts have resulted in the advent of a weighted scoring system that could sensitively capture multiple-organ comorbidities prior to HCT. The HCT-comorbidity index (HCT-CI) has provided better prediction of HCT-related morbidity and mortality than other non-HCT-specific indices. Subsequent studies, with the exception of a few studies with modest numbers of patients, have confirmed the prognostic importance of the HCT-CI. Further, the HCT-CI has been consolidated with various disease-specific and patient-specific risk factors to refine assignments of patients to the appropriate HCT setting. Ongoing studies are addressing prospective validation of the HCT-CI, furthering our understanding of biological aging, and enhancing the applicability of the HCT-CI comorbidity coding. Future knowledge of the impacts of multiple comorbidities on post-HCT toxicities might guide new prophylactic and therapeutic interventions to lessen the procedure's mortality.

A modified EBMT risk score and the hematopoietic cell transplantation-specific comorbidity index for pre-transplant risk assessment in adult acute lymphoblastic leukemia

BACKGROUND

Disease stage is the most important prognostic parameter in allogeneic hematopoietic cell transplantation (HCT) for acute lymphoblastic leukemia, but other factors such as donor/host histocompatibility and gender combination, recipient age, performance status and comorbidities need to be considered. Several scoring systems are available to predict outcome in HCT recipients; however, their prognostic relevance in acute lymphoblastic leukemia is not well defined.

DESIGN AND METHODS

In the present study we evaluated a modified EBMT risk score (mEBMT) and the HCT-specific comorbidity index (HCT-CI) in 151 adult acute lymphoblastic leukemia patients who received allogeneic HCT from 1995 until 2007 at our center.

RESULTS

Disease status was first complete remission (CR1) (47%), CR>1 (21%) or no CR (32%). Overall survival (OS) at one, two and five years was 62%, 51% and 40% and non-relapse mortality (NRM) was 21%, 24% and 32%. Median mEBMT was 3 (0-6). Higher mEBMT was associated with inferior OS (hazard ratio per score unit (HR): 1.50, P<0.001), higher NRM (HR: 1.36, P=0.042) and higher relapse mortality (HR: 1.68, P<0.001). Disease stage was the predominant prognostic factor in this score. Comorbidities were present in 71% of patients with mild hepatic disease (29%), moderate pulmonary disease (28%) and infections (23%) being the most common. Median HCT-CI was 1 (0-9). In univariate analysis a trend for inferior OS (HR: 1.08, P=0.20) and higher NRM (HR: 1.14, P=0.11) with increasing HCT-CI was observed but the level of significance was not reached. In additional analyses we found that reduced Karnofsky Performance Status (KPS) was associated with inferior OS (HR: 1.34, P=0.023) and higher relapse mortality (HR: 1.71, P=0.001) when analyzed univariately. However, KPS was associated with disease stage and significance was lost in multivariate analysis.

CONCLUSIONS

The mEBMT was prognostic in our patient cohort with predominant influence of disease stage, whereas a trend but no significant prognostic value was observed for the HCT-CI.

Comparison of two pretransplant predictive models and a flexible HCT-CI using different cut off points to determine low-, intermediate-, and high-risk groups: the flexible HCT-CI Is the best predictor of NRM and OS in a population of patients undergoing allo-RIC

Patient comorbidities are being increasingly analyzed as predictors for outcome after hematopoietic stem cell transplantation (HSCT), especially in allogeneic HSCT (Allo-HSCT). Researchers from Seattle have recently developed several pretransplant scoring systems (hematopoietic cell transplantation comorbidity index [HCT-CI] and the Pretransplantation Assessment of Mortality (PAM) model) from large sets of HSCT recipients with the aim of improving non-transplant models, mainly the Charlson Comorbidity Index (CCI). The validation of these comorbidity indexes in other institutions and in different disease and conditioning-related settings is of interest to determine whether these models are potentially applicable in clinical practice and in research settings. We performed a retrospective study in our institution including 194 consecutive reduced-intensity conditioning (RIC) AlloHSCT (allo-RIC) recipients to compare the predictive value of the PAM score, CCI, the original HCT-CI, and the flexible HCT-CI using a different risk group stratification. The median patient pretransplant scores for the HCT-CI, PAM, and CCI were 3.5, 22, and 0, respectively. The flexible HCT-CI risk-scoring system (restratified as: low risk [LR] 0-3 points, intermediate risk [IR] 4-5 points, and high risk [HR] >5 points) was the best predictor for non-relapse mortality (NRM). The 100-day and 2-year NRM incidence in these risk categories was 4% (95% confidence interval C.I. 2%-11%), 16% (95% C.I. 9%-31%), and 29% (95% C.I. 19%-45%), respectively (P < .001), and 19% (95% C.I. 12%-28%), 33% (95% C.I. 22%-49%), and 40% (95% C.I. 28%-56%), respectively (P=.01). However, we found no predictive value for NRM using neither the original HCT-CI nor the PAM or CCI models. The better predictive capacity for NRM of the flexible HCT-CI than PAM and CCI was confirmed with the c-statistics (c-statistics of 0.672, 0.634, and 0.595, respectively). Regarding the 2-year overall survival (OS), the flexible HCT-CI score categories were also associated with the highest predictive HR. In conclusion, our single-center study suggests that the flexible HCT-CI is a good predictor of 2-year NRM and survival after an allo-RIC.

Differential prognostic impact of pretransplant comorbidity on transplant outcomes by disease status and time from transplant: a single Japanese transplant centre study

This retrospective study examined the differences in the prognostic impact of the haematopoietic cell transplantation-specific comorbidity index (HCT-CI) on transplant outcomes by disease status and time from transplant in allogeneic haematopoietic stem cell transplantation (HSCT) recipients at a Japanese transplant centre. Of 187 patients, nonrelapse mortality (NRM) at 3 years was 9.6, 21.2 and 27.8% in the low-risk (score 0), intermediate-risk (score 1-2) and high-risk (score > or =3) HCT-CI groups, respectively (P=0.03). The corresponding overall survival (OS) at 3 years was 70.1, 60.5 and 38.9%, respectively (P<0.01). In multivariate analyses, high-risk HCT-CI significantly predicted higher NRM (relative risk, (RR) 2.44 (95% confidence interval, (CI) 1.02-5.85); P=0.04) and worse OS (RR 2.02 (95% CI 1.15-3.54); P=0.01). In the subgroup analysis according to disease status, the HCT-CI was associated with OS (P<0.01) and NRM (P=0.07) in patients with low-risk diseases, but not in those with high-risk diseases. Within patients who survived without relapse >1 year after HSCT, the HCT-CI did not predict OS (P=0.59) or NRM (P=0.31). These findings can be useful to determine the role of pretransplant comorbidity in allogeneic HSCT.