Primary colon lymphomas: An analysis of our experience over the last 18 years.

Colon lymphoma is a rare type of gastrointestinal lymphoma and represents 0.2% to -1.2% of all primary colon cancers. This study aimed to retrospectively examine the general characteristics, treatment methods, and survival characteristics of patients with colon lymphoma who were followed-up at our center. This retrospective study included patients diagnosed with colon lymphoma who were followed up at Ankara Numune Training and Research Hospital and Ankara Bilkent City Hospital between December 2005 and June 2023. Clinicopathological features, radiological findings, treatments, and modalities of patients were obtained from their medical records. Fourteen patients with primary colon lymphoma were included in the study. Thirteen patients (92.9%) were diagnosed with diffuse large B-cell lymphoma. The median age of the patients was 55 (28-84) years. The tumor location was the terminal ileum/cecum in 50% of the patients. At the time of diagnosis, 10 patients (7 with stage 1E-2E disease, 2 with stage 3E disease, and 1 with stage 4E disease due to tumor obstruction) underwent surgery. Twelve patients received chemotherapy (6 patients as adjuvant and 6 patients as first-line treatment). The median overall survival (OS) was 10 years (0.1-21.5) years, the 5-year median OS was 71%, and the 10-year median OS was 53%. Primary colon lymphoma is a rare disease and its optimal treatment is not clearly defined. The primary treatment for primary colon lymphoma is a combination of surgery and chemotherapy. A clear consensus on the treatment can be established through prospective studies.

The synergistic immunotherapeutic impact of engineered CAR-T cells with PD-1 blockade in lymphomas and solid tumors: a systematic review.

Currently, therapies such as chimeric antigen receptor-T Cell (CAR-T) and immune checkpoint inhibitors like programmed cell death protein-1 (PD-1) blockers are showing promising results for numerous cancer patients. However, significant advancements are required before CAR-T therapies become readily available as off-the-shelf treatments, particularly for solid tumors and lymphomas. In this review, we have systematically analyzed the combination therapy involving engineered CAR-T cells and anti PD-1 agents. This approach aims at overcoming the limitations of current treatments and offers potential advantages such as enhanced tumor inhibition, alleviated T-cell exhaustion, heightened T-cell activation, and minimized toxicity. The integration of CAR-T therapy, which targets tumor-associated antigens, with PD-1 blockade augments T-cell function and mitigates immune suppression within the tumor microenvironment. To assess the impact of combination therapy on various tumors and lymphomas, we categorized them based on six major tumor-associated antigens: mesothelin, disialoganglioside GD-2, CD-19, CD-22, CD-133, and CD-30, which are present in different tumor types. We evaluated the efficacy, complete and partial responses, and progression-free survival in both pre-clinical and clinical models. Additionally, we discussed potential implications, including the feasibility of combination immunotherapies, emphasizing the importance of ongoing research to optimize treatment strategies and improve outcomes for cancer patients. Overall, we believe combining CAR-T therapy with PD-1 blockade holds promise for the next generation of cancer immunotherapy.

Real-world experience of commercial relmacabtagene autoleucel (relma-cel) for relapsed/refractory central nervous system lymphoma: a multicenter retrospective analysis of patients in China.

BACKGROUND: Relapsed/refractory (R/R) central nervous system lymphomas (CNSLs) are associated with a poor prognosis. Relmacabtagene autoleucel (relma-cel), expressing the same chimeric antigen receptor (CAR) as lisocabtagene maraleucel, with an optimized commercial-ready process developed in China, demonstrated remarkable efficacy and manageable safety in the pivotal RELIANCE study. However, no published data are available on the "real-world" use of relma-cel, especially for patients with CNS involvement. PATIENTS AND METHODS: Retrospective analyses were conducted for commercial relma-cel used in patients with R/R CNSL at 12 clinics. The primary endpoint was to evaluate the proportion of patients who achieved complete response (CR) at 3 months. Secondary endpoints included best complete response (BCR), progression-free survival (PFS), duration of response (DOR), overall survival (OS), and the incidence of adverse events. RESULTS: Among the 22 CNSL patients (12 primary CNSLs; 10 secondary CNSLs), the best overall response rate was 90.9% and the BCR rate was 68.2%. With median follow-up of 316 days (range, 55-618 days), the estimated 1-year PFS rate, DOR, and OS rate were 64.4%, 71.5%, and 79.2%, respectively. Significant clinical benefits were observed in patients who were in durable CR or partial response to the most recent prior therapy preleukapheresis and received relma-cel as consolidation therapy (n=8), with 1-year PFS rate of 100.0% versus 41.7% (p=0.02). In addition, in terms of primary endpoint, non-CR at 3 months postinfusion seemed to be predictive of a worse prognosis, with an estimated 1-year PFS of 83.3% versus 37.0% (p=0.03), respectively. CRS occurred in 72.9% of patients (grade 3: 4.5%) and immune effector cell-associated neurotoxicity syndrome in 36.4% of patients (grade 3: 4.5%). With the add-on agent PD-1 inhibitor (tislelizumab) to the ongoing BTKi, significant re-expansions of CAR T-cell were detected by quantitative PCR or flow cytometry after a median of 2 weeks (range, 12-32 days). CONCLUSIONS: This study was the first and largest real-world study of commercial relma-cel for R/R CNSL, demonstrating promising efficacy and acceptable safety. We reaffirmed the benefit of immuno-agents such as BTKi or PD-1 inhibitor on CAR T-cell re-expansion and hypothesized a dual-agent CAR-T related combinatorial therapies, which warrants further validation. Most importantly, we highlighted the earlier use of CAR T-cell therapy as a consolidative therapy for patients sensitive to salvage therapy, which provided an impetus and inspired-future strategy.

[Malignant lymphomas - quo vadis? - What developments await us in diagnostics and therapy?] / Maligne Lymphome ­ Quo vadis?

The diagnosis and treatment of malignant lymphoma is rapidly advancing, offering hope but also highlighting inherent limitations. Technological breakthroughs in sequencing technologies enable more precise subtyping and risk stratification. For example, in diffuse large B-cell lymphoma (DLBCL), exome sequencing revealed molecular subtypes. Understanding these subtypes sheds light on lymphomagenesis and prognosis, and may provide targets for tailored therapies. Additionally, tumor-derived cell-free DNA (ctDNA) detected in blood plasma allows for genotyping, risk stratification, and measurement of minimal residual disease (MRD). Current studies often examine drug effectiveness through "all-comer" approaches or in transcriptionally defined subtypes. Molecular agnostic studies increasingly focus on clinically defined high-risk patients (e.g., using the IPI) to better demonstrate the statistical significance of therapy effects. Improved patient selection can enhance the cost-effectiveness of modern, often expensive, therapies.

Sequential CD7 CAR T-Cell Therapy and Allogeneic HSCT without GVHD Prophylaxis.

BACKGROUND: Patients with relapsed or refractory hematologic cancers have a poor prognosis. Chimeric antigen receptor (CAR) T-cell therapy as a bridge to allogeneic hematopoietic stem-cell transplantation (HSCT) has the potential for long-term tumor elimination. However, pre-HSCT myeloablation and graft-versus-host disease (GVHD) prophylaxis agents have toxic effects and could eradicate residual CAR T cells and compromise antitumor effects. Whether the integration of CAR T-cell therapy and allogeneic HSCT can preserve CAR T-cell function and improve tumor control is unclear. METHODS: We tested a novel "all-in-one" strategy consisting of sequential CD7 CAR T-cell therapy and haploidentical HSCT in 10 patients with relapsed or refractory CD7-positive leukemia or lymphoma. After CAR T-cell therapy led to complete remission with incomplete hematologic recovery, patients received haploidentical HSCT without pharmacologic myeloablation or GVHD prophylaxis drugs. Toxic effects and efficacy were closely monitored. RESULTS: After CAR T-cell therapy, all 10 patients had complete remission with incomplete hematologic recovery and grade 4 pancytopenia. After haploidentical HSCT, 1 patient died on day 13 of septic shock and encephalitis, 8 patients had full donor chimerism, and 1 patient had autologous hematopoiesis. Three patients had grade 2 HSCT-associated acute GVHD. The median follow-up was 15.1 months (range, 3.1 to 24.0) after CAR T-cell therapy. Six patients remained in minimal residual disease-negative complete remission, 2 had a relapse of CD7-negative leukemia, and 1 died of septic shock at 3.7 months. The estimated 1-year overall survival was 68% (95% confidence interval [CI], 43 to 100), and the estimated 1-year disease-free survival was 54% (95% CI, 29 to 100). CONCLUSIONS: Our findings suggest that sequential CD7 CAR T-cell therapy and haploidentical HSCT is safe and effective, with remission and serious but reversible adverse events. This strategy offers a feasible approach for patients with CD7-positive tumors who are ineligible for conventional allogeneic HSCT. (Funded by the National Natural Science Foundation of China and the Key Project of Science and Technology Department of Zhejiang Province; ClinicalTrials.gov numbers, NCT04599556 and NCT04538599.).

Lymphoma of the central nervous system originating from the septum pellucidum region: Two case reports with literature review.

RATIONALE: Central nervous system lymphoma (CNSL) originating from the septum pellucidum is exceptionally rare, presenting unique diagnostic and therapeutic complexities. This case report aims to elucidate the diagnostic challenges, treatment strategies, and outcomes of this rare manifestation. By documenting this case, we seek to enhance understanding within the medical community and contribute valuable insights to the management of CNSL, particularly in atypical locations. PATIENT CONCERNS: A 45-year-old female presented with persistent headaches, blurred vision, and motor weakness, prompting a thorough neurological evaluation. Imaging revealed an enhancing mass in the septum pellucidum, leading to the diagnosis of CNSL. The patient's concerns encompassed not only the physical symptoms but also the emotional impact of her diagnosis and treatment journey. DIAGNOSES: Diagnostic confirmation of CNSL involved cerebrospinal fluid analysis and imaging findings, highlighting the challenge of distinguishing lymphoma from other intracranial pathologies. The case underscores the importance of comprehensive diagnostic evaluation in rare CNSL presentations. INTERVENTIONS: Multidisciplinary management included high-dose methotrexate-based chemotherapy and corticosteroids, with consideration for neurosurgical intervention. Psychosocial support and self-care strategies were integrated into the treatment plan to address holistic patient needs. OUTCOMES: Monitoring revealed a positive treatment response, with a reduction observed in the septum pellucidum mass. Regular assessments ensured adherence to interventions and management of treatment-related side effects, contributing to favorable outcomes and improved quality of life for the patient. LESSONS: This case emphasizes the significance of meticulous diagnostic evaluation and personalized treatment approaches in managing rare CNSL presentations. Collaboration among specialists and comprehensive patient support is paramount in optimizing outcomes and addressing the multifaceted challenges posed by CNSL in unique anatomical locations.

Serum Levels of miR-122-5p and miR-125a-5p Predict Hepatotoxicity Occurrence in Patients Undergoing Autologous Hematopoietic Stem Cell Transplantation.

Hepatic complications are an acknowledged cause of mortality and morbidity among patients undergoing hematopoietic stem cell transplantation. In this study, we aimed to evaluate the potential role in the prediction of liver injury of five selected microRNAs (miRNAs)-miR-122-5p, miR-122-3p, miR-15b-5p, miR-99b-5p, and miR-125a-5p-in the setting of autologous hematopoietic stem cell transplantation (ASCT). A total of 66 patients were included in the study: 50 patients (75.8%) with multiple myeloma (MM) and 16 (24.2%) with lymphoma. Blood samples were collected after the administration of the conditioning regimen, on the day of transplant (day 0). The expression levels of selected miRNAs were quantified by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) using the miRCURY LNA miRNA Custom PCR Panels (QIAGEN). In a multivariate logistic regression analysis adjusted for age, sex, and the administered conditioning regimen, two miRNAs, hsa-miR-122-5p (odds ratio, OR 2.10, 95% confidence interval, CI: 1.29-3.42, p = 0.0029) and hsa-miR-125a-5p (OR 0.27, 95% CI: 0.11-0.71, p = 0.0079), were independent for hepatic toxicity occurrence during the 14 days after transplant. Our model in 10-fold cross-validation preserved its diagnostic potential with a receiver operating characteristics area under the curve (ROC AUC) of 0.75, 95% CI: 0.63-0.88 and at optimal cut-off reached 72.0% sensitivity and 74.4% specificity. An elevated serum level of miR-122-5p and decreased level of miR-125a-5p on day 0 are independent risk factors for hepatotoxicity in ASCT recipients, showing promise in accurately predicting post-ASCT complications. Identifying patients susceptible to complications has the potential to reduce procedure costs and optimize the selection of inpatient or outpatient procedures.

Sociodemographic factors and Child Opportunity Index disparities associated with missed care opportunities in pediatric patients with lymphoma and leukemia referred for FDG-PET/CT.

BACKGROUND: Little data exists on the association of missed care opportunities (MCOs) in children referred for nuclear medicine/nuclear oncology imaging examinations and socioeconomic disparities. OBJECTIVE: To determine the prevalence of MCOs in children with lymphoma/leukemia scheduled for fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) and the impact of sociodemographic factors and Child Opportunity Index (COI). MATERIALS AND METHODS: Retrospective analysis of MCOs in children with lymphoma/leukemia scheduled for FDG-PET/CT (2012 to 2022) was performed. In univariate analysis, patient, neighborhood, and appointment data were assessed across MCOs and completed appointments. Logistic regression evaluated independent effects of patient-, neighborhood-, and appointment-level factors with MCOs. Two-sided P-value < .05 was considered statistically significant. RESULTS: In 643 FDG-PET/CT appointments (n = 293 patients; median age 15 years (IQR 11.0-17.0 years); 37.9% female), there were 20 MCOs (3.1%) involving 16 patients. Only 8.2% appointments involved Black/African American non-Hispanic/Latino patients, yet they made up a quarter of total MCOs. Patients living in neighborhoods with very low or low COI experienced significantly higher MCOs versus zip codes with very high COI (6.9% vs. 0.8%; P = 0.02). Logistic regression revealed significantly increased likelihood of MCOs for patients aged 18 to 21 [odds ratio (OR) 4.50; 95% CI 1.53-13.27; P = 0.007], Black/African American non-Hispanic/Latino (OR 3.20; 95% CI 1.08-9.49; P = 0.04), zip codes with very low or low COI (OR 9.60; 95% CI 1.24-74.30; P = 0.03), and unknown insurance status. CONCLUSION: Children with lymphoma/leukemia, living in zip codes with very low or low COI, and who identified as Black/African American non-Hispanic/Latino experienced more MCOs. Our study supports the need to address intersecting sociodemographic, neighborhood, and health system factors that will improve equitable access to necessary healthcare imaging for children.

High yield killing of lymphoma cells by anti-CD22 CAR-NK cell therapy.

Chimeric antigen receptors (CARs) offer a promising new approach for targeting B cell malignancies through the immune system. Despite the proven effectiveness of CAR T cells targeting CD19 and CD22 in hematological malignancies, it is imperative to note that their production remains a highly complex process. Unlike T cells, NK cells eliminate targets in a non-antigen-specific manner while avoiding graft vs. host disease (GvHD). CAR-NK cells are considered safer than CAR-T cells because they have a shorter lifespan and produce less toxic cytokines. Due to their unlimited ability to proliferate in vitro, NK-92 cells can be used as a source for CAR-engineered NK cells. We found that CARs created from the m971 anti-CD22 mAb, which specifically targets a proximal CD22 epitope, were more effective at anti-leukemic activity compared to those made with other binding domains. To further enhance the anti-leukemic capacity of NK cells, we used lentiviral transduction to generate the m971-CD28-CD3ζ NK-92. CD22 is highly expressed in B cell lymphoma. To evaluate the potential of targeting CD22, Raji cells were selected as CD22-positive cells. Our study aimed to investigate CD22 as a potential target for CAR-NK-92 therapy in the treatment of B cell lymphoma. We first generated m971-CD28-CD3ζ NK-92 that expressed a CAR for binding CD22 in vitro. Flow cytometric analysis was used to evaluate the expression of CAR. The 7AAD determined the cytotoxicity of the m971-CD28-CD3ζ NK-92 towards target lymphoma cell lines by flow cytometry assay. The ELISA assay evaluated cytokine production in CAR NK-92 cells in response to target cells. The m971-CD28-CD3ζ NK-92 cells have successfully expressed the CD22-specific CAR. m971-CD28-CD3ζ NK-92 cells efficiently lysed CD22-expressing lymphoma cell lines and produced large amounts of cytokines such as IFN-γ and GM-CSF but a lower level of IL-6 after coculturing with target cells. Based on our results, it is evident that transferring m971-CD28-CD3ζ NK-92 cells could be a promising immunotherapy for B cell lymphoma.

Real-world status of treatment for lymphoid neoplasms developed during the course of myeloproliferative neoplasms in Japan.

OBJECTIVES: Patients with myeloproliferative neoplasms (MPNs) are at higher risk of developing secondary malignancies. In this study, we focused on patients with MPNs that complicated lymphoid neoplasms. To analyze the real-world status of lymphoid neoplasm treatment in patients with pre-existing MPNs in Japan, we conducted a multicenter retrospective study. METHODS: Questionnaires were sent to collect the data on patients who were first diagnosed with either polycythemia vera, essential thrombocythemia or myelofibrosis and who later were complicated with lymphoid neoplasms defined as malignant lymphoma, multiple myeloma, or chronic lymphocytic leukemia/small cell lymphoma. RESULTS: Twenty-four patients with MPNs complicated by lymphoid neoplasms were enrolled (polycythemia vera, n = 8; essential thrombocythemia, n = 14; and primary myelofibrosis, n = 2). Among these, diffuse large B-cell lymphoma (DLBCL) was the most frequently observed (n = 13, 54.1%). Twelve (92.3%) of the patients with DLBCL received conventional chemotherapy. Among these 12 patients, regarding cytoreductive therapy for MPNs, 8 patients stopped treatment, one continued treatment, and two received a reduced dose. Consequently, most patients were able to receive conventional chemotherapy for DLBCL with a slightly higher dose of granulocyte colony-stimulating factor support than usual without worse outcomes. All 3 patients with multiple myeloma received a standard dose of chemotherapy. CONCLUSION: Our data indicate that if aggressive lymphoid neoplasms develop during the course of treatment in patients with MPNs, it is acceptable to prioritize chemotherapy for lymphoma.

Update on FDG-PET in pediatric lymphoma.

Lymphoma represent the third most common malignant disease in childhood and adolescence. They are divided into pediatric Hodgkin lymphoma (P-HL) and pediatric non-Hodgkin lymphoma (P-NHL). In P-HL, excellent cure rates are achieved through combined modality treatment using chemotherapy and radiotherapy. For more than 20 years, FDG-PET has been an integral part of the treatment and guides its intensity through improved staging and precise assessment of chemotherapy response. In P-NHL, good cure rates are achieved with chemotherapy alone. At present FDG-PET plays only a subordinate role in the treatment setting. Its potential to contribute to treatment management is far from being fully utilised. In this article, the current status of FDG-PET in pediatric lymphoma is presented in detail. The core elements are the sections on staging and response assessment. In addition, challenges and pitfalls are discussed and future developments are outlined.

Clonal hematopoiesis-derived therapy-related myeloid neoplasms after autologous hematopoietic stem cell transplant for lymphoid and non-lymphoid disorders.

Therapy-related myeloid neoplasms (tMN) are complications of cytotoxic therapies. Risk of tMN is high in recipients of autologous hematopoietic stem cell transplantation (aHSCT). Acquisition of genomic mutations represents a key pathogenic driver but the origins, timing and dynamics, particularly in the context of preexisting or emergent clonal hematopoiesis (CH), have not been sufficiently clarified. We studied a cohort of 1507 patients undergoing aHSCT and a cohort of 263 patients who developed tMN without aHSCT to determine clinico-molecular features unique to post-aHSCT tMN. We show that tMN occurs in up to 2.3% of patients at median of 2.6 years post-AHSCT. Age ≥ 60 years, male sex, radiotherapy, high treatment burden ( ≥ 3 lines of chemotherapy), and graft cellularity increased the risk of tMN. Time to evolution and overall survival were shorter in post-aHSCT tMN vs. other tMN, and the earlier group's mutational pattern was enriched in PPM1D and TP53 lesions. Preexisting CH increased the risk of adverse outcomes including post-aHSCT tMN. Particularly, antecedent lesions affecting PPM1D and TP53 predicted tMN evolution post-transplant. Notably, CH-derived tMN had worse outcomes than non CH-derived tMN. As such, screening for CH before aHSCT may inform individual patients' prognostic outcomes and influence their prospective treatment plans. Presented in part as an oral abstract at the 2022 American Society of Hematology Annual Meeting, New Orleans, LA, 2022.

Patterns of follow-up care in adult blood cancer survivors-Prospective evaluation of health-related outcomes, resource use, and quality of life.

BACKGROUND: Information about follow-up care in blood cancer survivors is limited. The questionnaire-based "Aftercare in Blood Cancer Survivors" (ABC) study aimed to identify patterns of follow-up care in Germany and compare different types of follow-up institutions. METHODS: The study's 18-month prospective part compared the follow-up institutions identified in the preceding retrospective part (academic oncologists, community oncologists, primary care physicians). The questionnaires were completed by the follow-up physicians. RESULTS: Of 1070 physicians named by 1479 blood-cancer survivors, 478 (44.7%) consented to participate. For provision of care, most oncologists relied on published guidelines, while most primary care physicians depended on information from other physicians. Survivors with a history of allogeneic transplantation or indolent lymphoma were mainly seen by academic oncologists, whereas survivors with monoclonal gammopathy, multiple myeloma, or myeloproliferative disorders were often seen by community oncologists, and survivors with a history of aggressive lymphoma or acute leukemia by primary care physicians. Detection of relapse and secondary diseases was consistently viewed as the most important follow-up goal. Follow-up visits were most extensively documented by academic oncologists (574 of 1045 survivors cared for, 54.9%), followed by community oncologists (90/231, 39.0%) and primary care physicians (51/203, 25.1%). Relapse and secondary disease detection rates and the patients' quality of life were similar at the three institutions. Laboratory tests were most often ordered by academic oncologists, and imaging by primary care physicians. Psychosocial issues and preventive care were more often addressed by primary care physicians than by oncologists. CONCLUSIONS: Patients at high risk of relapse or late complications were preferentially treated by academic oncologists, while patients in stable condition requiring continuous monitoring were also seen by community oncologists, and patients with curable diseases in long-term remission by primary care physicians. For the latter, transfer of follow-up care from oncologists to well-informed primary care providers appears feasible.

T-cell help in the tumor microenvironment enhances rituximab-mediated NK-cell ADCC.

ABSTRACT: Rituximab (RTX) and other monoclonal antibodies (mAbs) that bind directly to malignant cells are of great clinical value but are not effective for all patients. A major mechanism of action of RTX is antibody-dependent cellular cytotoxicity (ADCC) mediated by natural killer (NK) cells. Prior in vitro studies in our laboratory demonstrated that T cells contribute to maintaining the viability and cytotoxic potential of NK cells activated by anti-CD20-coated target B cells. Here, we conducted studies using a novel mouse model and clinical correlative analysis to assess whether T-cell help contribute to RTX-mediated NK-cell ADCC in the tumor microenvironment (TME) in vivo. A humanized mouse model was developed using Raji lymphoma cells and normal donor peripheral blood mononuclear cells that allows for control of T-cell numbers in the lymphoma TME. In this model, NK-cell viability and CD16 and CD25 expression dropped after RTX in the absence of T cells but increased in the presence of T cells. RTX therapy was more effective when T cells were present and was ineffective when NK cells were depleted. In patients with indolent lymphoma, fine needle aspirates were obtained before and ∼1 week after treatment with a RTX-containing regimen. There was a strong correlation between CD4+ T cells as well as total T cells in the pretherapy TME and an increase in NK-cell CD16 and CD25 expression after RTX. We conclude that T-cell help in the TME enhances RTX-mediated NK-cell viability and ADCC.

The Musculoskeletal Tumor Society Clinical Practice Guideline on the Management of Metastatic Humeral Disease.

Management of Metastatic Humeral Disease is based on a systematic review of published studies surrounding the management of metastatic disease, multiple myeloma, and lymphoma limited to the humerus. This guideline contains seven action statements to assist orthopaedic surgeons, orthopaedic oncologists, physicians, and any other qualified healthcare professionals involved in the surgical management of metastatic disease of the humerus. It is also intended to serve as an information resource for decision makers, researchers, and developers of clinical practice guidelines. In addition to providing pragmatic practice recommendations, this guideline also highlights gaps in the literature and informs areas for future research and quality measure development. This guideline has been endorsed by the American Academy of Orthopaedic Surgeons.

Increased PD-1 Expression on Circulating T Cells Correlates with Inferior Outcome after Autologous Stem Cell Transplantation.

High-dose chemotherapy followed by autologous stem cell transplantation (auto-SCT) is a well-established treatment option for multiple myeloma and malignant lymphoma patients. It is able to induce long-term progression-free survival (PFS) in both patient groups and even provide a cure in patients with aggressive lymphoma. However, relapse is common and has been associated with the pace and quality of immunologic reconstitution after transplantation, as well as with immune cell exhaustion and immunometabolic defects. We aimed to analyze the dynamics of the prototypical exhaustion marker PD-1 on immune cells during reconstitution on high-dose chemotherapy followed by auto-SCT and its impact on PFS. We performed a comprehensive analysis of exhaustion and metabolic markers on immune cells from myeloma and lymphoma patients undergoing auto-SCT using flow cytometry and NanoString technologies. The expression levels of PD-1 were increased during early reconstitution after transplantation on T cells and natural killer (NK) cells, as well as on monocytes. However, while PD-1 expression in NK cells and monocytes normalized over time, PD-1 expression on T cells demonstrated a variable course. Of note, lymphoma patients with continuously increasing PD-1 expression on T cells after auto-SCT had an inferior median PFS of only 146 days, whereas the median PFS was not reached in the lymphoma patients without such a PD-1 expression pattern. T cells from patients with increased PD-1 expression after auto-SCT exhibited an immunometabolic (over)activation and exhausted phenotype compared to T cells from patients with a low PD-1 expression after transplantation, including higher levels of the glycolytic pacemaker enzyme hexokinase 2 and the inhibitory receptor CTLA-4. In addition, proliferating Ki-67+ T cells were more abundant in patients with high PD-1 expression on T cells compared to those with low expression after auto-SCT (11.9% versus 4.2%). PD-1 expression on T cells might serve as an adverse biomarker for lymphoma patients undergoing auto-SCT; however, further validation by larger prospective studies is required.