Efficacy of salvage chemotherapy in diffuse large B cell lymphoma with primary treatment failure according to putative cell of origin

Clinical outcomes in transplant-eligible patients with relapsed or refractory diffuse large B-cell lymphoma after second-line salvage chemotherapy: A retrospective study

OBJECTIVE

The prognosis of patients with relapsed or refractory (R/R) diffuse large B-cell lymphoma (DLBCL) is poor. Although patients who fail first-line salvage chemotherapy are candidates for second-line salvage chemotherapy, the optimal treatment strategy for these patients has not yet been established.

METHODS

The present, single-center, retrospective study included transplant-eligible patients with R/R DLBCL who received second-line salvage chemotherapy with curative intent.

RESULTS

Seventy-six patients with R/R DLBCL received second-line salvage chemotherapy. Eighteen (23.7%) patients were responders to the first-line salvage chemotherapy. The overall response rate was 39.5%, and overall survival (OS) was significantly longer in patients who responded to second-line salvage chemotherapy than those who did not. Forty-one patients who proceeded to potentially curative treatment (autologous hematopoietic stem cell transplantation [ASCT], chimeric antigen receptor [CAR] T-cell therapy, or allogeneic hematopoietic stem cell transplantation) had a better prognosis than those who did not. Among the 46 patients who failed to respond to the second-line salvage regimen, only 18 (39.1%) could proceed to the curative treatments. However, among the 30 patients who responded to the second-line salvage regimen, 23 (76.7%) received one of the potentially curative treatments. Among 34 patients who received CAR T-cell therapy, OS was significantly longer in those who responded to salvage chemotherapy immediately prior to CAR T-cell therapy than in those who did not respond. In contrast, the number of prior lines of chemotherapy was not identified as a statistically significant prognostic factor of survival. No significant difference was detected in OS between patients receiving ASCT and those receiving CAR T-cell therapy after the response to second-line salvage chemotherapy.

DISCUSSION

In this study, we demonstrated that chemosensitivity remained a crucial factor in predicting survival outcomes following CAR T-cell therapy irrespective of the administration timing, and that both ASCT and CAR T-cell therapy were acceptable after the response to second-line salvage chemotherapy.

Fractionated ifosfamide, carboplatin, and etoposide with rituximab as a safe and effective treatment for relapsed/refractory diffuse large B cell lymphoma with severe comorbidities

Although treatment outcomes for diffuse large B cell lymphoma (DLBCL) have improved with the introduction of rituximab, approximately half of patients experience relapsed/refractory (r/r) disease. Furthermore, no standard salvage therapy has yet been established to date, while limitations in treatment options exist due to toxicity and restricted tolerability among elderly patients and/or those with comorbidities. The ICE (ifosfamide, cyclophosphamide, and etoposide) regimen is often used as salvage therapy for r/r DLBCL. Several modified ICE regimens not requiring continuous ifosfamide infusion are available, which can be used in outpatient clinics. This study analyzed the efficacy and toxicity of fractionated ICE with rituximab (f-R-ICE) as a salvage regimen among 47 patients with relapsed/refractory DLBCL (median age upon f-R-ICE initiation, 71 years). The whole cohort had an overall (ORR) and complete response rate of 53.1% (n = 25) and 25.5% (n = 12), respectively, and an estimated 1-year overall survival after f-R-ICE initiation of 57%. Comorbidities were evaluated using the Charlson Comorbidity Index (CCI) upon f-R-ICE initiation. Patients with low CCI scores (68%) had a higher ORR than those with high CCI scores (36.4%) upon f-R-ICE initiation (P = 0.042). In contrast, no significant differences in overall survival (OS) were observed between the low and high CCI groups (1-year OS 56.6% vs. 52.2%; median OS 24 vs. 22.8 months) after initiating f-R-ICE. Our results suggest that f-R-ICE is a safe and effective salvage therapy for r/r DLBCL and can be used for older patients and/or those with high CCI scores in outpatient clinics.

Prognostic Nomogram and Predictive Factors in Refractory or Relapsed Diffuse Large B-Cell Lymphoma Patients Failing Front-Line R-CHOP Regimens

Background: The clinical course of relapsed or refractory (r/r) diffuse large B-cell lymphoma (DLBCL) is variable, with limited efficacy data of second-line treatment in a post-rituximab real-world context. Hence, we explored the predictors and constructed a nomogram for risk stratification in this population.

Patients and methods: Among 296 r/r DLBCL patients pretreated with R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone) at the Cancer Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College between 2006 and 2017, 231 were included for nomogram construction. After randomization, we constructed the prognostic nomogram in the primary cohort (n=161) based on a multivariate analysis and confirmed it in the validation cohort (n=70). Additionally, we explored predictive factors for second-line therapy using a ordinal regression analysis.

Results: Four independent prognostic factors including rituximab in the second-line setting, initial Eastern Cooperative Oncology Group (ECOG) performance status (PS), response to front-line treatment, and invasion on progression/recurrence were used to construct the nomogram. The nomogram had a C index of 0.70 with AUC values of 0.73 and 0.71 for the primary and validation cohorts, respectively. Subsequently, three risk groups (low, intermediate, and high) were determined with median overall survival (OS) of 38.0, 25.0, and 7.0 months, respectively. Additionally, we conducted a multivariate ordinal regression analysis and identified prior response to front-line treatment (odds ratio=4.50, 95% CI: 1.84-11.27, p=0.001) and bulky disease at diagnosis (odds ratio=0.36, 95% CI: 0.182-0.702, p=0.003) were two independent factors for second-line treatment efficacy.

Conclusions: The established predictors for treatment efficacy and the novel nomogram for survival in r/r DLBCL patients could potentially be applied for risk stratification and treatment guidance in the post-rituximab era.