[Efficacy and safety of first-line treatment with anti-CD38 monoclonal antibody-based regimen for primary plasma cell leukemia].

Objective: To analyze the efficacy and safety of first-line treatment with an anti-CD38 monoclonal antibody regimen for primary plasma cell leukemia (pPCL). Methods: Patients diagnosed with pPCL from December 1st, 2018 to July 26th, 2023, receiving first-line treatment of anti-CD38 monoclonal antibody-based regimens across multiple centers including Peking University People's Hospital, Fuxing Hospital of Capital Medical University, Qingdao Municipal Hospital, Shengjing Hospital of China Medical University, Handan Central Hospital, the First Affiliated Hospital of Harbin Medical University, the Fourth Hospital of Hebei Medical University and General Hospital of Ningxia Medical University were consecutively included. A total of 24 pPCL patients were included with thirteen being male and eleven being female. The median age [M(Q1, Q3)] was 60 (57, 70) years. Patients were grouped according to peripheral blood plasma cell (PBPC) percentage [5%-19% (n=14) vs ≥20% (n=10)]. Last follow-up date was September 26th, 2023. The median follow-up period was 9.1 (4.2, 15.5) months. Patients' data related with clinical baseline characteristics, efficacy, survival and safety were retrospectively collected. Cox proportional hazards regression model was used to analyze risk factors associated with survival. Results: Among 24 pPCL patients, 16 (66.7%) patients had anemia at diagnosis, 13(54.2%) patients had thrombocytopenia, 8 (33.3%) patients had a baseline estimated glomerular filtration rate (eGFR)<40 ml·min-1·(1.73m2)-1, 13 (54.2%) patients had elevated lactate dehydrogenase (LDH) levels. The median PBPC percentage was 16% (8%, 26%) . Fluorescence in situ hybridization testing indicated that patients harboring 17p deletion, t(4;14) or t(14;16) were 6 (25.0%), 4 (16.7%) and 4 (16.7%), respectively. The overall response rate was 83.3% (20/24). The median progression-free survival (PFS) was 20.5 (95%CI: 15.8-25.2) months, and the median overall survival (OS) was not reached. Estimated 1-year and 2-year PFS and OS rates were 75.0% and 89.1%, 37.5% and 53.4%, respectively. The median PFS and OS for patients with PBPC percentages 5%-19% and≥20% were not reached and 20.5 (95%CI:15.7-25.3) months, 17.8 months and not reached, respectively. There was no significant statistical difference of PFS and OS between two groups (all P>0.05). Multivariate Cox regression analysis showed that 1p32 deletion was the risk factor associated with PFS (HR=7.7, 95%CI: 1.1-54.9, P=0.043). Seventeen patients (70.8%) developed grade 3-4 hematologic toxicities. Twelve patients (50.0%) developed grade 3-4 thrombocytopenia. Sixteen patients (66.7%) developed infection. All hematologic toxicities and infections were improved after supportive treatment. Conclusion: First-line treatment with anti-CD38 monoclonal antibody-based therapy for pPCL is effective and safe.

[Effect of Circulating Plasma Cells on the Prognosis of Patients with Multiple Myeloma].

OBJECTIVE: to analyze the effect of circulating plasma cells(CPC) on the prognosis of patients with multiple myeloma(MM) in the era of new drugs, and to explore the new definition standard of primary plasma cell leukemia(pPCL). METHODS: The clinical data of 321 patients with newly diagnosed MM and 21 patients with pPCL admitted to our hospital from January 2014 to May 2022 were retrospectively analyzed. According to the proportion of CPC in peripheral blood smears, all patients were divided into 4 groups: CPC 0% group(211 cases), CPC 1%-4% group(69 cases), CPC 5%-19% group(41 cases) and CPC≥20% group(21 cases). The clinical features of patients in each group were compared and the prognosis fators was analyzed. RESULTS: The median OS of the four groups were 44.5,21.3,24.6 and 12.8 months, respectively. Among them, 295 patients(86.3%) were treated with new drugs, and the median OS of the four groups were not reached, 26.7, 24.6 and 14.9 months, respectively. As the survival curves of CPC 5%-19% group and CPC≥20% group were similar, the patients were divided into CPC<5% group and CPC≥5% group, the median OS of CPC<5% group was better than that in CPC≥5% (43.5 vs 22.3 months, P<0.001). In addition, the median OS of patients in the CPC 1%-4% group was also significantly lower than that in the CPC 0% group and similar to that in the CPC≥5% group. Multivariate analysis showed that 1%-4% CPC was an independent risk factor for the OS of patients with CPC<5%. The patients with CPC<5% were stratified by R-ISS staging, and the OS of R-ISS stage Ⅰ or stage Ⅱ with 1%-4% CPC was similar to that of R-ISS stage Ⅲ. The newly defined pPCL patients showed increased tumor load and obvious invasive characteristics. Multivariate analysis showed no independent prognostic factors for pPCL, and high-risk cytogenetic abnormalities(HRCA) had no significant effect on the prognosis. CONCLUSION: The validity of IMWG's new pPCL definition standard was verified, and it was found that the survival of MM with 1%-4% CPC also is poor and the prognosis is very close to pPCL. In addition, the newly defined pPCL has unique clinical and biological characteristics.

Improved Screening of Monoclonal Gammopathy Patients by MALDI-TOF Mass Spectrometry.

Monoclonal gammopathies are a group of blood diseases characterized by presence of abnormal immunoglobulins in peripheral blood and/or urine of patients. Multiple myeloma and plasma cell leukemia are monoclonal gammopathies with unclear etiology, caused by malignant transformation of bone marrow plasma cells. Mass spectrometry with matrix-assisted laser desorption/ionization and time-of-flight detection is commonly used for investigation of the peptidome and small proteome of blood plasma with high accuracy, robustness, and cost-effectivity. In addition, mass spectrometry coupled with advanced statistics can be used for molecular profiling, classification, and diagnosis of liquid biopsies and tissue specimens in various malignancies. Despite the fact there have been fully optimized protocols for mass spectrometry of normal blood plasma available for decades, in monoclonal gammopathy patients, the massive alterations of biophysical and biochemical parameters of peripheral blood plasma often limit the mass spectrometry measurements. In this paper, we present a new two-step extraction protocol and demonstrated the enhanced resolution and intensity (>50×) of mass spectra obtained from extracts of peripheral blood plasma from monoclonal gammopathy patients. When coupled with advanced statistics and machine learning, the mass spectra profiles enabled the direct identification, classification, and discrimination of multiple myeloma and plasma cell leukemia patients with high accuracy and precision. A model based on PLS-DA achieved the best performance with 71.5% accuracy (95% confidence interval, CI = 57.1-83.3%) when the 10× repeated 5-fold CV was performed. In summary, the two-step extraction protocol improved the analysis of monoclonal gammopathy peripheral blood plasma samples by mass spectrometry and provided a tool for addressing the complex molecular etiology of monoclonal gammopathies.

Clinical and cytogenetic characteristics of primary and secondary plasma cell leukemia under the new IMWG definition criteria: a retrospective study.

BACKGROUND: Plasma cell leukemia (PCL) is a rare and aggressive plasma cell disorder, exhibiting a more unfavorable prognosis than multiple myeloma. PCL is classified into pPCL and sPCL. Recently, the IMWG has recommended new PCL definition criteria, which require the presence of ≥5% circulating plasma cells in peripheral blood smears. Due to its low incidence, research on pPCL and sPCL is limited. METHODS: We conducted a retrospective study and analyzed clinical and cytogenetic data of pPCL and sPCL patients. Overall survival (OS) and progression-free survival (PFS) were assessed by the Kaplan-Meier method, and survival distributions were compared using the log-rank test. RESULTS: This is a small cohort comprising 23 pPCL and 9 sPCL patients. Notably, sPCL patients showed a higher incidence of extramedullary infiltration and a higher percentage of bone marrow plasma cells (p = 0.015 and 0.025, respectively). Although no significant difference was found between the two groups in OS and PFS, a trend emerged suggesting a superior survival outcome for pPCL patients, with a higher cumulative 1-year PFS rate (38.3% vs. 13.3%) and a lower early mortality rate (mortality rate at 3 months: 15% vs. 33%). We also suggested that pPCL patients carrying t(11;14) may have a longer median survival time than individuals with other cytogenetic abnormalities, but this was not confirmed due to the small sample size. CONCLUSION: Our study revealed clinical and cytogenetic features of pPCL and sPCL patients according to the new diagnostic criteria. The findings suggested a generally better prognosis for pPCL than sPCL and the likelihood of t(11;14) translocation acting as a favorable prognostic factor in pPCL. It is important to note that our study had a limited sample size, which may lead to bias. We hope well-designed studies can be conducted to provide more results.

Clinical and Laboratory Characteristics of IgM Primary Plasma Cell Leukemia.

BACKGROUND: The aim of the study was to investigate the clinical and laboratory characteristics of IgM primary plasma cell leukemia. METHODS: We retrospectively analyzed a case of clinical and laboratory characteristics of IgM primary plasma cell leukemia and review related literature of patient with primary plasma cell leukemia. RESULTS: Laboratory tests: Alanine aminotransferase 128 U/L, Aspartate aminotransferase 245 U/L, Globulin 47.8 g/L, Lactate dehydrogenase 1,114 U/L, Creatinine 111.7 mol/L, Serum calcium 2.47 mmol/L, ß2 microglobulin 8.52 µg/mL, Immunoglobulin G 31.41 g/L, D-dimer 2.34 mg/L, Prothrombin time 13.6 seconds Fibrinogen 2 g/L, White blood cell 7.38 x 109/L, Red blood cell 3.46 x 1012/L, Hemoglobin 115 g/L, Platelet 7 x 109/L, and 12% Primitive naive cells can be seen in peripheral blood smear. Bone marrow smear: Accounted for 52% of original cells, the cell size, shape is irregular, the edge is not neat, the cell quality is rich, stained gray blue, cytoplasmic staining uneven, some devouring blood cells can be seen in the cytoplasm or unknown substance, the nucleus shape is irregular, visible distortion and fold, is visible on the part of the nuclei cavitation sample inclusions, chromatin is meticulous, partly visible large nucleoli. Flow cytometry results showed abnormal cell group held 23.85% of nuclear cells, expression of CD38, CD138, CD117, cKappa, partly CD20, weak expressing CD45, not express CD27, CD19, CD56, CD200, CD81, cLambda. It was a monoclonal plasma cell with an abnormal phenotype, consistent with a plasma cell tumor. Immunofixation electrophoresis results showed that the serum M protein was 22.80 g/L, which was IgG-κ type, the serum free KAP light chain was 232.69 mg/L, the serum free LAM light chain was 5.37 mg/L, and the rFLC (κ-FLC: λFLC) was 43.33. The diagnosis was primary plasmacytic leukemia of light chain type. CONCLUSIONS: Primary plasma cell leukemia (pPCL) is a rare and highly aggressive plasma cell malignancy. Laboratory staff should pay more attention to and recognize the pleomorphic morphology of neoplastic plasma cells, which can enable timely clinical development of bone marrow smear, biopsy, flow cytometry, and cytogenetic tests providing help in early diagnosis and treatment.

Identification of signature genes and drug candidates for primary plasma cell leukemia: An integrated system biology approach.

BACKGROUND: Plasma cell leukemia (PCL) is one of the rare cancer which is characterized by the uncontrolled proliferation of plasma cells in peripheral blood and bone marrow. The aggressive behavior of the disease and high mortality rate among PCL patients makes it a thirst area to be explored. METHODS: The dataset for PCL was obtained from the GEO database and was analyzed using GEO2R for differentially expressed genes. Further, the functional enrichment analysis was carried out for DEGs using DAVID. The protein-protein interactions (PPI) for DEGs were obtained using STRING 11.5 and were analyzed in Cytoscape 3.7.2. to obtain the key hub genes. These key hub genes were investigated for their interaction with suitable drug candidates using DGIdb, DrugMAP, and Schrodinger's version 2022-1. RESULTS: Out of the total of 104 DEGs, 39 genes were up-regulated whereas 65 genes were down-regulated. A total of 11 biological processes, 2 cellular components, and 5 molecular functions were enriched along with the 7 KEGG pathways for the DEGs. Further, a total of 11 hub genes were obtained from the PPI of DEGs of which TP53, MAPK1, SOCS1, MBD3, and YES1 were the key hub genes. Oxaliplatin, mitoxantrone, and ponatinib were found to have the highest binding affinity towards the p53, MAPK1, and YES1 proteins respectively. CONCLUSION: TP53, MAPK1, SOCS1, MBD3, and YES1 are the signature hub genes that might be responsible for the aggressive prognosis of PCL leading to poor survival rate. However, p53, MAPK1, and YES1 can be targeted with oxaliplatin, mitoxantrone, and ponatinib.

[Clinical Characteristics and Survival Analysis of Patients with Plasma Cell Leukemia].

OBJECTIVE: To investigate the clinical characteristics, therapeutic response and prognosis of patients with plasma cell leukemia (PCL) and improve the understanding of this disease. METHODS: The clinical manifestations, laboratory tests and treatment response of 27 patients with plasma cell leukemia treated in The Second Hospital of Shanxi Medical University from December 2010 to August 2019 were analyzed retrospectively, and their clinical characteristics were summarized. Kaplan-Meier method was used for survival analysis. RESULTS: There were 18 cases of primary plasma cell leukemia (pPCL) and 9 cases of secondary plasma cell leukemia (sPCL). The male to female ratio was 1.7∶1. The median age was 62 years old. The first manifestations were bone pain, fatigue, fever, splenomegaly and bleeding, and a large number of plasma cell infiltration was observed in the morphological examination of peripheral blood and bone marrow cells. 13 cases were detected by immunotyping and all of them expressed CD38/CD138. 8 cases underwent karyotype analysis, and 3 cases were normal, clonal abnormalities occurred in 5 cases. FISH detection was performed in 12 cases, of which 8 cases were abnormal. In 17 cases of bortezomib based chemotherapy, the ovevall response rate was 52.9%, which was higher than that in the non-bortezomib group, but there was no significant difference between the two groups (P =0.242). The overall median survival time of 27 patients was 6.4 months, the median progression-free survival time was 3.5 months, and the median survival time of patients with pPCL and sPCL was 8.2 months and 2.4 months, respectively, the difference between the two groups was statistically significant (P =0.031). CONCLUSION: PCL is highly invasive and has diverse clinical manifestations, and is not sensitive to traditional chemotherapy. The median survival time of patients with pPCL is relatively longer than that of patients with sPCL. The chemotherapy regimen based on bortezomib improves the treatment effectiveness and prolongs the survival time of PCL patients.

[Clinical Features and Prognosis of Multiple Myeloma Patients with Secondary Primary Malignancies].

OBJECTIVE: To explore the clinical characteristics and prognosis of multiple myeloma(MM) patients with secondary primary malignancies. METHODS: The clinical data of newly diagnosed MM patients admitted to the First Affiliated Hospital of Zhengzhou University from January 2011 to December 2019 were retrospectively analyzed. The patients with secondary primary malignancies were retrieved, and their clinical features and prognosis were evaluated. RESULTS: A total of 1 935 patients with newly diagnosed MM were admitted in this period, with a median age of 62 (18-94) years old, of which 1 049 cases were hospitalized twice or more. There were eleven cases with secondary primary malignancies (the incidence rate was 1.05%), including three cases of hematological malignancies (2 cases of acute myelomonocytic leukemia and 1 case of acute promyelocytic leukemia) and eight cases of solid tumors (2 cases of lung adenocarcinoma, and 1 case each of endometrial cancer, esophageal squamous cell carcinoma, primary liver cancer, bladder cancer, cervical squamous cell carcinoma, and meningioma). The median age of onset was 57 years old. The median time between diagnosis of secondary primary malignancies and diagnosis of MM was 39.4 months. There were seven cases with primary or secondary plasma cell leukemia, the incidence rate was 0.67%, and the median age of onset was 52 years old. Compared with the randomized control group, the ß2-microglobulin level in the secondary primary malignancies group was lower (P=0.028), and more patients were in stage I/II of ISS (P=0.029). Among the 11 patients with secondary primary malignancies, one survived, ten died, and the median survival time was 40 months. The median survival time of MM patients after the secondary primary malignancies was only seven months. All seven patients with primary or secondary plasma cell leukemia died, with a median survival time of 14 months. The median overall survival time of MM patients with secondary primary malignancies was longer than that of the patients with plasma cell leukemia (P=0.027). CONCLUSION: The incidence rate of MM with secondary primary malignancies is 1.05%. MM patients with secondary primary malignancies have poor prognosis and short median survival time, but the median survival time is longer than that of patients with plasma cell leukemia.

Improved survival of patients with primary plasma cell leukemia with VRd or daratumumab-based quadruplets: A multicenter study by the Greek myeloma study group.

We evaluated the efficacy and prognostic impact of bortezomib-lenalidomide triplet (VRd) or daratumumab-based quadruplets (DBQ) versus previous anti-myeloma therapies, that is, bortezomib standard combinations (BSC) or conventional chemotherapy (CT), in a large cohort of patients with primary plasma cell leukemia (pPCL), including those fulfilling the revised diagnostic criteria, that is, circulating plasma cells (cPCS): ≥5%; 110 pPCL patients (M/F: 51/59; median age 65 years, range: 44-86) out of 3324 myeloma patients (3%), registered in our database between 2001 and 2021, were studied; 37% had cPCS 5%-19%; 89% received novel combinations including DBQ (21%), VRd (16%) and BSC (52%); 35% underwent autologous stem cell transplantation. 83% achieved objective responses. Treatment with VRd/DBQ strongly correlated with a higher complete response rate (41% vs. 17%; p = .008). After a median follow-up of 51 months (95% CI: 45-56), 67 patients died. Early mortality was 3.5%. Progression-free survival was 16 months (95% CI: 12-19.8), significantly longer in patients treated with VRd/DBQ versus BSC/CT (25 months, 95% CI: 13.5-36.5 vs. 13 months 95% CI: 9-16.8; p = .03). Median overall survival (OS) was 29 months (95% CI: 19.6-38.3), significantly longer in patients treated with VRd/DBQ versus BSC/CT (not reached vs. 20 months, 95% CI: 14-26; 3-year OS: 70% vs. 32%, respectively; p < .001; HzR: 3.88). In the multivariate analysis VRd/DBQ therapy, del17p(+) and PLT <100.000/µL, independently predicted OS (p < .05). Our study has demonstrated that in the real-world setting, treatment with VRd/DBQ induces deep and durable responses and is a strong prognostic factor for OS representing currently the best therapeutic option for pPCL.

Plasma Cell Leukemia with Successful Upfront Venetoclax in Combination with Allogeneic Transplantation.

BACKGROUND Plasma cell leukemia (PCL) is an aggressive form of plasma cell neoplasm. We report the first case of primary PCL successfully treated with upfront novel agents consisting of Venetoclax and daratumumab in combination with intensive chemotherapy and allogeneic transplantation. CASE REPORT A 59-year-old woman presented with epistaxis, gum bleeding, and blurred vision. On examination, she appeared pale, with multiple petechiae and hepatomegaly. Fundoscopy revealed retinal hemorrhages. Laboratory investigations revealed bicytopenia and leukocytosis, with mild coagulopathy and hypofibrinogenemia. Elevated globulin and calcium levels were also observed. Serum protein electrophoresis demonstrated IgG lambda paraproteinemia, with a serum-free light chain kappa-to-lambda ratio of 0.074. A skeletal survey revealed the presence of lytic lesions. Bone marrow investigations confirmed the presence of lambda-light-chain-restricted clonal plasma cells. FISH detected t(11;14) and 17p13.1 deletion. Therefore, a final diagnosis of primary PCL was made. The patient received 1 cycle of bortezomib, cyclophosphamide, and dexamethasone (VCD) and 5 cycles of Venetoclax-VCD, followed by an unsuccessful stem cell mobilization. One cycle of daratumumab in combination with bortezomib, lenalidomide, and dexamethasone (VRD) was then given. The patient achieved complete remission. She underwent allogeneic stem cell transplantation of an HLA-matched sibling donor. Post-transplant marrow assessment showed disease remission and absence of t(11;14) and 17p deletions. She was administered pamidronate and lenalidomide maintenance. She remained clinically well with a good performance status and no active graft-versus-host disease 18 months after transplant. CONCLUSIONS The success of our patient in achieving complete remission has highlighted the efficacy and safety of this novel therapy in the front-line management of PCL.

Isolated relapse of plasma cell leukemia in the central nervous systems: a case report and literature review.

Plasma cell leukemia is a rare yet aggressive form of multiple myeloma characterized by high levels of plasma cells circulating in the peripheral blood. We recently experienced a case of plasma cell leukemia that had been in stringent complete remission for nine years after autologous stem cell transplantations with subsequent courses of lenalidomide maintenance therapy, and then relapsed as an extramedullary plasmacytoma in the central nervous system. Assessment of the bone marrow did not prove proliferation of plasma cells at relapse, but imbalanced elevation of serum levels of free light chains was observed without changes in other clinical biomarkers including immunoglobulin levels. Salvage chemotherapy with isatuximab, pomalidomide, and dexamethasone (IsaPD) was promptly initiated. After two courses of IsaPD, significant remission was achieved and the neuronal symptoms completely resolved. When excessive serum levels of clonotypic free light chains are noted, their significance should be carefully assessed even when plasma cell propagation in the bone marrow is not observed. In such cases, hematologists should search for extramedullary proliferation of plasma cells, including in the immune-privileged central nervous system.

Angioimmunoblastic T-cell lymphoma presenting with severe plasmacytosis mimicking plasma cell leukemia.

Peripheral blood smear (A) demonstrates increased numbers of plasma cells (representative cells indicated by arrows), (B) demonstrates polytypic nature of plasma cells.

Primary plasma cell leukemia in Latin America: demographic, clinical, and prognostic characteristics. A study of GELAMM group.

Primary plasma cell leukemia (pPCL) is an infrequent and aggressive plasma cell disorder. The prognosis is still very poor, and the optimal treatment remains to be established. A retrospective, multicentric, international observational study was performed. Patients from 9 countries of Latin America (LATAM) with a diagnosis of pPCL between 2012 and 2020 were included. 72 patients were included. Treatment was based on thalidomide in 15%, proteasome inhibitors (PI)-based triplets in 38% and chemotherapy plus IMIDs and/or PI in 29%. The mortality rate at 3 months was 30%. The median overall survival (OS) was 18 months. In the multivariate analysis, frontline PI-based triplets, chemotherapy plus IMIDs and/or PI therapy, and maintenance were independent factors of better OS. In conclusion, the OS of pPCL is still poor in LATAM, with high early mortality. PI triplets, chemotherapy plus IMIDs, and/or PI and maintenance therapy were associated with improved survival.

The Current State of Knowledge About Evolution of Multiple Myeloma to Plasma Cell Leukemia.

Plasma cell leukemia is a rare form of multiple myeloma (MM). In contrast to de novo primary plasma cell leukemia (pPCL), which is very uncommon presentation of MM, there is increasing frequency of transformation to secondary plasma cell leukemia (sPCL) with increasing survival of patients (MM). The molecular basis of sPCL remains poorly understood sPCL is particularly aggressive and is associated with an extremely poor prognosis, constituting a major unmet medical need. High-quality data in sPCL regarding presentation, treatment and outcomes is limited. Herein we review the current state of knowledge on sPCL diagnostics, molecular biology, clinical characteristics, prognosis and reported treatment outcomes and the emergence of the new therapeutic strategies.

Comparison of autologous and allogeneic hematopoietic cell transplantation strategies in patients with primary plasma cell leukemia, with dynamic prediction modeling.

Primary plasma cell leukemia (pPCL) is a rare and challenging malignancy. There are limited data regarding optimum transplant approaches. We therefore undertook a retrospective analysis from 1998-2014 of 751 patients with pPCL undergoing one of four transplant strategies; single autologous transplant (single auto), single allogeneic transplant (allo-first) or a combined tandem approach with an allogeneic transplant following an autologous transplant (auto-allo) or a tandem autologous transplant (auto-auto). To avoid time bias, multiple analytic approaches were employed including Cox models with time-dependent covariates and dynamic prediction by landmarking. Initial comparisons were made between patients undergoing allo-first (n=70) versus auto-first (n=681), regardless of a subsequent second transplant. The allo-first group had a lower relapse rate (45.9%, 95% confidence interval [95% CI]: 33.2-58.6 vs. 68.4%, 64.4-72.4) but higher non-relapse mortality (27%, 95% CI: 15.9-38.1 vs. 7.3%, 5.2-9.4) at 36 months. Patients who underwent allo-first had a remarkably higher risk in the first 100 days for both overall survival and progression-free survival. Patients undergoing auto-allo (n=122) had no increased risk in the short term and a significant benefit in progression-free survival after 100 days compared to those undergoing single auto (hazard ratio [HR]=0.69, 95% CI: 0.52- 0.92; P=0.012). Auto-auto (n=117) was an effective option for patients achieving complete remission prior to their first transplant, whereas in patients who did not achieve complete remission prior to transplantation our modeling predicted that auto-allo was superior. This is the largest retrospective study reporting on transplantation in pPCL to date. We confirm a significant mortality risk within the first 100 days for allo-first and suggest that tandem transplant strategies are superior. Disease status at time of transplant influences outcome. This knowledge may help to guide clinical decisions on transplant strategy.