Tazemetostat for relapsed/refractory B-cell non-Hodgkin lymphoma with EZH2 mutation in Japan: 3-year follow-up for a phase II study.

Previously, we reported the efficacy and safety of tazemetostat in Japanese patients with relapsed/refractory follicular lymphoma (FL) and diffuse large B-cell lymphoma (DLBCL) harboring the EZH2 mutation in a multicenter, open-label, phase II study. Here, we present a follow-up analysis of tazemetostat at a long-term median follow-up of 35.0 months. Twenty patients were enrolled: 17 in the FL cohort and three in the DLBCL cohort. In the FL cohort, the objective response rate was 70.6%, consistent with the primary analysis, and the median progression-free survival (PFS) was not reached. The 24-month and 36-month PFS rates were 72.1% (95% confidence interval [CI] 41.5%-88.6%) and 64.1% (95% CI 33.7%-83.4%), respectively. The median duration of treatment was 30.2 months. After the primary analysis at a median follow-up of 12.9 months, grade 1-2 urinary tract infection, peripheral motor neuropathy, and hypogammaglobulinemia newly emerged, but the incidence of adverse events (AEs) did not increase notably during this follow-up period. No unexpected grade ≥ 3 treatment-related AEs were reported. Long-term oral monotherapy with tazemetostat showed favorable efficacy and safety profiles, indicating that it may be a useful third-line or later treatment option for patients with relapsed/refractory FL harboring the EZH2 mutation. Trial registration: ClinicalTrials.gov: NCT03456726.

Small cell pattern of ALK-negative anaplastic large cell lymphoma with double-hit rearrangements of DUSP22 and TP63.

In ALK-negative anaplastic large cell lymphoma (ALCL), gene rearrangements of DUSP22 and TP63 are considered mutually exclusive. The former predicts a favorable prognosis, while the latter is generally unfavorable. We report the first case of ALK-negative ALCL in a leukemic phase with small cell pattern transformation, harboring double-hit rearrangements of the DUSP22 gene by inv(6)(p25q21) and TP63 gene by TBL1XR1-TP63 inversion. Despite the resistance to chemotherapies, the patient remained in remission with allogeneic stem cell transplantation over 20 months. Recognizing this pathologically and genetically rare condition is needed for prompt diagnosis and therapeutic decision-making in ALK-negative ALCL.

The impact of renal function on initial therapy in transplant-ineligible multiple myeloma patients.

The prognosis for multiple myeloma (MM) patients has improved with the advent of new drugs, but the prognosis with renal impairment (RI) is poor. The choice of treatment in such cases is critical, but there are no set criteria. We examined the impact of RI on initial therapy in transplant-ineligible MM patients. We selected symptomatic MM patients who met the following criteria: age ≥ 65 years, fit, and ineligible for transplantation from the database. We analyzed the impact of age, treatment, International Staging System (ISS) stage, karyotype abnormalities, performance status, and estimated glomerular filtration rate (GFR < 50 or ≥ 50 ml/min/1.73m2) on overall survival (OS). We also analyzed the OS by eGFR for each treatment. We selected 349 symptomatic MM patients. The regimens used were lenalidomide, bortezomib and dexamethasone (RVd), daratumumab, bortezomib, melphalan, and prednisolone (D-VMP), daratumumab, lenalidomide and dexamethasone (D-Rd) and daratumumab, bortezomib, and dexamethasone (D-Vd) in 184, 41, 74 and 50 patients, respectively. The median age was 74 years old; ISS stage was I/II/III in 85/112/131 patients; and 161 patients showed eGFR < 50. The OS was shorter with ISS stage III (p = 0.029) and eGFR < 50 (p < 0.001) by multivariate analysis. The OS under the RVd/D-Rd regimens were significantly shorter for patients with eGFR < 50, but OS under the D-VMP/D-Vd regimens were not significantly different between patients with eGFR < 50 and eGFR ≥ 50. The OS of the transplant-ineligible MM patients with higher ISS stage and RI was poor. Initial treatment with a D-VMP/D-Vd regimen might be less affected by RI.

An Autopsy Case of Severe COVID-19 Pneumonia Complicated by Intrapulmonary Thrombosis in Myelodysplastic/Myeloproliferative Neoplasm With Ring Sideroblasts and Thrombocytosis.

Patients with coronavirus disease 2019 (COVID-19) pneumonia are prone to intrapulmonary thrombosis owing to excessive inflammation and platelet activation. Myelodysplastic/myeloproliferative neoplasm (MDS/MPN) with ring sideroblasts and thrombocytosis (RS-T) is a rare disease in MDS/MPN overlap entities. Patients with MDS/MPN RS-T are known to be at a high risk of thrombosis, and platelet count control with drug therapy does not necessarily reduce this risk. Here, we report the autopsy case of an older male patient with MDS/MPN RS-T and severe COVID-19 pneumonia complicated by intrapulmonary thrombosis. His platelet count had been controlled in the normal range after treatment with hydroxyurea and 5-aza-2'-deoxycytidine. On admission day, he rapidly developed respiratory distress and tested positive on a polymerase chain reaction test for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). After admission, he received supplemental oxygen and was administered remdesivir and dexamethasone; however, his respiratory and circulatory status did not improve. The patient died on day 4 of illness. Autopsy findings revealed massive thrombi within blood vessels and diffuse alveolar damage in both lungs, which were determined to be the cause of death. In patients with MDS/MPN RS-T combined with COVID-19 pneumonia, clinicians may need to pay close attention to the risk of pulmonary thrombosis.

Long-term efficacy and safety of tucidinostat in patients with relapsed or refractory peripheral T-cell lymphoma: final analysis of phase IIb results.

Not available.

Good's Syndrome With Pure Red Cell Aplasia and Subclinical Myasthenia Gravis: A Case Report and Review of Literature.

Good's syndrome is a pathologic condition characterized by thymoma and immunoglobulin disorder. Here, we report a rare case of a patient with Good's syndrome with simultaneous pure red cell aplasia (PRCA) and subclinical myasthenia gravis with detectable serum anti-acetylcholine receptor antibody (AChR Ab). While thymectomy did not result in the improvement of any paraneoplastic syndromes, cyclosporine A (CsA) treatment successfully improved PRCA; however, hypoglobulinemia was not recovered, and anti-AchR Ab did not disappear by CsA treatment in our case. A review of the literature on simultaneous Good's syndrome with PRCA also suggested the efficacy of CsA on PRCA but not hypoglobulinemia, suggesting the distinct underlying mechanisms between these two paraneoplastic symptoms with thymoma. Future research is needed to understand the mechanism underlying this rare pathologic condition and to generate appropriate treatment.

The lymphocyte/monocyte ratio predicts the efficacy of isatuximab plus pomalidomide in multiple myeloma patients.

BACKGROUND: Isatuximab, an anti-CD38 antibody, has been widely used in treatments for patients with relapsed/refractory multiple myeloma (MM). Despite its high efficacy, not all patients achieve a lasting therapeutic response with isatuximab. OBJECTIVE: We tried to identify biomarkers to predict the effectiveness of isatuximab by focusing on the host's immune status before treatment. METHODS: We retrospectively analyzed the cases of 134 relapsed/refractory MM patients in the Kansai Myeloma Forum database who had received only a first isatuximab treatment. RESULTS: Among the 134 patients, an isatuximab, pomalidomide and dexamethasone (Isa-PD) regimen, isatuximab, carfilzomib and dexamethasone (Isa-KD) regimen and isatuximab and/or dexamethasone (Isa-D) regimen were used in 112, 15 and 7 patients, respectively. The median age at treatment, number of prior treatment regimens, and progression-free survival (PFS) were 71, 6, and 6.54 months, respectively. Multivariate analysis showed that the PFS under the Isa-PD regimen was longer in patients with higher lymphocyte/monocyte ratio (LMR ≥ 4), fewer prior treatment regimens (< 6), and no use of prior daratumumab treatment. The OS under the Isa-PD regimen was longer in patients with higher white blood cell counts (WBC counts ≥ 3000/µL) and higher LMR. The PFS under the Isa-D regimen was longer in patients with fewer prior treatment regimens in univariate analysis, but no parameters were correlated with PFS/OS under the Isa-KD regimen. CONCLUSION: We found that the patients with higher LMR (≥ 4) could obtain longer PFS and OS under the Isa-PD regimen. Other cohort studies of isatuximab treatment might be necessary to substantiate our results.

Nirmatrelvir Resistance in an Immunocompromised Patient with Persistent Coronavirus Disease 2019.

Although the coronavirus disease 2019 (COVID-19) pandemic is coming to an end, it still poses a threat to the immunocompromised and others with underlying diseases. Especially in cases of persistent COVID-19, new mutations conferring resistance to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) therapies have considerable clinical implications. We present a patient who independently acquired a T21I mutation in the 3CL protease after nirmatrelvir exposure. The T21I mutation in the 3CL protease is one of the most frequent mutations responsible for nirmatrelvir resistance. However, limited reports exist on actual cases of SARS-CoV-2 with T21I and other mutations in the 3CL protease. The patient, a 55 year-old male, had COVID-19 during chemotherapy for multiple myeloma. He was treated with nirmatrelvir early in the course of the disease but relapsed, and SARS-CoV-2 with a T21I mutation in the 3CL protease was detected in nasopharyngeal swab fluid. The patient had temporary respiratory failure but later recovered well. During treatment with remdesivir and dexamethasone, viruses with the T21I mutation in the 3CL protease showed a decreasing trend during disease progression while increasing during improvement. The impact of drug-resistant SARS-CoV-2 on the clinical course, including its severity, remains unknown. Our study is important for examining the clinical impact of nirmatrelvir resistance in COVID-19.

Analyzing the risk factors for disease progression within 2 years and histological transformation in patients treated with rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone as first-line treatment: A 15-year follow-up of patients with advanced follicular lymphoma in JCOG0203.

Follicular lymphoma (FL) is an indolent lymphoma that becomes aggressive due to histological transformation (HT), leading to reduced survival. Patients with FL have different clinical courses and various treatment options. Some patients exhibit shorter survival and experience disease progression within 24 months of diagnosis/treatment (POD24); the optimal treatment remains an unmet needs. Thus, identifying factors that predict shorter survival is essential to stratify treatment and prolong the survival of patients with FL. To analyze risk factors for POD24 and HT in patients treated with rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) as first-line treatment, we performed this post-hoc analysis of patients with advanced indolent B-cell lymphoma in a randomized clinical trial wherein six cycles of R-CHOP were administered every 2-3 weeks. The primary analysis showed no differences in outcomes, which enabled the analysis of 248 patients with FL, assigned to two arms. All histopathological specimens from the 300 enrolled patients were reviewed by three expert hematopathologists. Multivariable analysis implicated Follicular Lymphoma International Prognostic Index (FLIPI) intermediate (odds ratio [OR] 2.531, 95% confidence interval [CI] 0.676-9.466) and high- (OR 2.236, 95% CI 0.160-31.226) risks, B symptoms (OR 2.091, 95% CI 0.747-5.851), and grade 3A (G3A) (OR 1.833, 95% CI 0.634-5.299) as risk factors for POD24. Furthermore, multivariable analysis through a median follow-up of 15.9 years implicated G3A (OR 2.628, 95% CI 0.806-8.575) and high-risk FLIPI (OR 4.401, 95% CI 0.186-104.377) as risk factors for HT. However, an analysis limited to the first 10 years revealed that the prognostic factors elucidated from the longer-term analysis had a greater impact on HT. G3A and high-risk FLIPI may independently predict POD24 and HT, thereby informing treatment stratification of patients with untreated advanced-stage FL in future trials, particularly to address the unmet needs of patients with POD24.

ctDNA improves prognostic prediction for patients with relapsed/refractory MM receiving ixazomib, lenalidomide, and dexamethasone.

ABSTRACT: It remains elusive how driver mutations, including those detected in circulating tumor DNA (ctDNA), affect prognosis in relapsed/refractory multiple myeloma (RRMM). Here, we performed targeted-capture sequencing using bone marrow plasma cells (BMPCs) and ctDNA of 261 RRMM cases uniformly treated with ixazomib, lenalidomide, and dexamethasone in a multicenter, prospective, observational study. We detected 24 and 47 recurrently mutated genes in BMPC and ctDNA, respectively. In addition to clonal hematopoiesis-associated mutations, varying proportion of driver mutations, particularly TP53 mutations (59.2% of mutated cases), were present in only ctDNA, suggesting their subclonal origin. In univariable analyses, ctDNA mutations of KRAS, TP53, DIS3, BRAF, NRAS, and ATM were associated with worse progression-free survival (PFS). BMPC mutations of TP53 and KRAS were associated with inferior PFS, whereas KRAS mutations were prognostically relevant only when detected in both BMPC and ctDNA. A total number of ctDNA mutations in the 6 relevant genes was a strong prognostic predictor (2-year PFS rates: 57.3%, 22.7%, and 0% for 0, 1, and ≥2 mutations, respectively) and independent of clinical factors and plasma DNA concentration. Using the number of ctDNA mutations, plasma DNA concentration, and clinical factors, we developed a prognostic index, classifying patients into 3 categories with 2-year PFS rates of 57.9%, 28.6%, and 0%. Serial analysis of ctDNA mutations in 94 cases revealed that TP53 and KRAS mutations frequently emerge after therapy. Thus, we clarify the genetic characteristics and clonal architecture of ctDNA mutations and demonstrate their superiority over BMPC mutations for prognostic prediction in RRMM. This study is a part of the C16042 study, which is registered at www.clinicaltrials.gov as #NCT03433001.

Prognostic model for relapsed/refractory transplant-ineligible diffuse large B-cell lymphoma utilizing the lymphocyte-to-monocyte ratio.

We conducted a multi-institutional retrospective study in 100 transplant-ineligible (TI) patients with diffuse large B-cell lymphoma (DLBCL) that relapsed or progressed after first-line R-CHOP (or -like) therapy to develop a robust predictive model for TI relapsed/refractory (r/r) DLBCL, which has a heterogeneous but poor prognosis by currently available treatment modalities other than chimeric antigen receptor T-cell (CAR-T) therapy or bispecific antibodies. The median age at relapse or progression was 76 years. The median progression-free survival (PFS) and overall survival (OS) from the first progression were 11.5 months and 21.9 months, respectively. Multivariate analysis identified low lymphocyte-to-monocyte ratio (LMR), elevated high lactate dehydrogenase, and elevated C-reactive protein at progression as independent predictors of OS. A predictive model based on these three factors, here designated as the Kyoto Prognostic Index for r/r DLBCL (KPI-R), successfully stratified their OS and PFS with statistical significance. In addition, event-free survival less than 24 months for R-CHOP and low LMR were identified as significant predictive factors for non-response in any sequence of salvage therapy. We concluded that LMR is a bonafide predictor of treatment response and prognosis in patients with TI r/r DLBCL, and may be helpful in treatment decision-making.

Primary analysis of a prospective cohort study of Japanese patients with plasma cell neoplasms in the novel drug era (2016-2021).

The emergence of novel drugs has significantly improved outcomes of patients with plasma cell neoplasms (PCN). The Japanese Society of Hematology conducted a prospective observational study in newly diagnosed PCN patients between 2016 and 2021. The analysis focused on 1385 patients diagnosed with symptomatic PCN between 2016 and 2018. The primary endpoint was the 3-year overall survival (OS) rate among patients requiring treatment (n = 1284), which was 70.0% (95%CI 67.4-72.6%). Approximately 94% of these patients received novel drugs as frontline therapy. The 3-year OS rate was 90.3% (95%CI 86.6-93.1%) in the 25% of patients who received upfront autologous stem cell transplantation (ASCT), versus just 61.4% (95%CI 58.0-64.6%) in those who did not receive upfront ASCT. The only unfavorable prognostic factor that affected OS in ASCT recipients was an age of 65 or higher. For patients who did not receive ASCT, independent unfavorable prognostic factors included frontline treatment with conventional chemotherapies, international staging system score of 2/3, extramedullary tumors, and Freiberg comorbidity index of 2/3. This study unequivocally demonstrates that use of novel drugs improved OS in Japanese myeloma patients, and underscores the continued importance of upfront ASCT as the standard of care in the era of novel drugs.

Autologous HSCT with novel agent-based induction and consolidation followed by lenalidomide maintenance for untreated multiple myeloma.

Triplet regimen comprising proteasome inhibitors, immunomodulatory drugs, and dexamethasone (DEX) is a recommended induction/consolidation therapy for multiple myeloma (MM) patients eligible for transplant. In this Japanese phase II study conducted from 2017 to 2019, newly diagnosed MM patients aged 20-65 received four induction cycles with bortezomib (Bor), lenalidomide (Len), and DEX (VRD), followed by Bor and high-dose melphalan with autologous stem cell rescue. Subsequently, they underwent four consolidation cycles with carfilzomib, Len, and DEX (KRD), followed by Len maintenance until disease progression. A total of 141 patients were analyzed. In an intent-to-treat population, the complete or better response post induction was 19.9%, rising to 39.7%, 58.9%, and 62.4% after transplant, consolidation, and 1-year maintenance, respectively. With a median follow-up of 38 months, the 3-year progression-free survival (PFS) rate was 83.5% and the 3-year overall survival rate was 92.5%. Severe adverse events (≥grade 3) occurred in ~30% of patients; however, there was no treatment-related mortality. These findings clearly showed the tolerability and effectiveness of this protocol. Nevertheless, patients with high-risk cytogenetics showed a trend toward lower 3-year PFS than those without (77.8% vs. 89.4%, p = 0.051), and ultra-high-risk cytogenetics (≥2 high-risk cytogenetics) had an even worse prognosis, with 61.2% 3-year PFS. To overcome this situation, a more potent treatment strategy incorporating novel agents such as the CD38-antibody should be assessed in future studies.

Efficacy of elotuzumab for multiple myeloma deteriorates after daratumumab: a multicenter retrospective study.

Elotuzumab-based regimens are sometimes selected for multiple myeloma treatment after daratumumab-based regimens. However, there has been insufficient discussion on the efficacy of elotuzumab after daratumumab. We used Kansai Myeloma Forum registration data in a multicenter retrospective evaluation of the efficacy of elotuzumab after daratumumab. Overall survival (OS) rate and time to next treatment (TTNT) were significantly worse in the cohort given elotuzumab after daratumumab (Dara cohort, n = 47) than in the cohort with no history of daratumumab administration before elotuzumab (No-Dara cohort, n = 80, OS: P = 0.03; TTNT: P = 0.02; best response: P < 0.01). In the Dara cohort, OS and TTNT rates were worse with sequential elotuzumab use after daratumumab than with non-sequential (OS: P = 0.02; TTNT: P = 0.03). In patients given elotuzumab < 180 days after daratumumab, OS (P = 0.08) and best response (P = 0.21) tended to be worse, and TTNT was significantly worse (P = 0.01), than in those given elotuzumab after ≥ 180 days. These findings were confirmed by subgroup analyses and multivariate analyses. Monoclonal-antibody-free treatment might be preferable after daratumumab-based regimens. If possible, elotuzumab-based regimens should be considered only ≥ 180 days after daratumumab use.

Skeletal muscle index impacts the treatment outcome of elderly patients with diffuse large B cell lymphoma.

Sarcopenia is a crucial factor in the physical fitness of elderly individuals. This study investigated the prognostic values of multiple parameters of sarcopenia in association with established prognostic factors in elderly Japanese patients with diffuse large B cell lymphoma (DLBCL). As candidate indicators for sarcopenia, the skeletal muscle index (SMI) (cm2 /m2 ), the psoas muscle index, the erector spinae muscle index, the visceral fat index, the subcutaneous fat index, and the visceral to subcutaneous fat area ratio at the third lumbar level were assessed by computed tomography at their initial diagnosis in 102 patients with DLBCL over 75 years old those were diagnosed and treated in our institute from 2007 to 2020. The primary endpoint was overall survival (OS), and the secondary endpoint was progression-free survival (PFS). The median age of patients analyzed was 80 years at diagnosis. The sex-specific cut-offs for the indices adopted two approaches: (i) the historical cut-off values established in the previous study for healthy Japanese individuals (Hamaguchi Y. J Cachexia Sarcopenia Muscle. 2018), and (ii) each sex-specific lowest quartile in our cohort. As the results, SMI evaluated by the historical cut-off and sex-specific lowest quartile was identified as the most influential independent prognostic factor for both OS and PFS among various parameters for sarcopenia. Furthermore, we developed an elderly sarcopenia prognostic index (ESPI). ESPI, which combines SMI evaluated by the historical cut-off and LDH > ULN, demonstrated statistically significant prognostic impacts on OS and PFS. Moreover, compared to the R-IPI, ESPI showed the ability to identify intermediate-risk groups and indicated a trend toward improved predictive accuracy. Our study revealed that SMI is the most appropriate assessment method for evaluating sarcopenia and the critical prognostic factor in OS and PFS of elderly patients with DLBCL.

Clinical impacts of severe thrombocytopenia in the first cycle of azacitidine monotherapy and cytogenetics in patients with myelodysplastic syndrome: The Kyoto Conditional Survival Scoring System.

Azacitidine (AZA) has been one of the standard treatments for transplantation-ineligible patients with myelodysplastic syndrome (MDS); however, hematological toxicities frequently cause treatment interruption in the early phase of the therapy. The present study conducted a multicenter retrospective study to investigate the prognostic impacts of various factors, including factors included in the Revised International Prognostic Scoring System (IPSS-R) and severe cytopenia in the early phase of AZA monotherapy in 212 patients with MDS. Severe cytopenia was evaluated after the initiation of therapy by absolute neutrophil counts on the 29th day after AZA (ANC29) initiation, and red cell concentrates (RCC) and platelet concentrate (PC) transfusion units required within 28 days from the start of AZA, designated in the present study as RCC28 and PC28, respectively. The survival period was determined from the 29th day of AZA treatment to death from any cause as the conditional survival period after the first cycle of AZA (CS-AZA1). Multivariate analysis demonstrated that severe thrombocytopenia defined by >30 units of PC28 and very poor risk cytogenetics according to IPSS-R were independent prognostic factors for CS-AZA1. The Kyoto Conditional Survival Scoring System was subsequently developed by incorporating severe thrombocytopenia defined by PC28 and very poor risk cytogenetics, which successfully stratified the risks of the patients in CS-AZA1. In conclusion, extreme PC transfusion dependency during the first cycle of AZA and very poor risk cytogenetics are important prognostic factors in AZA monotherapy for MDS.

A prospective, multicenter, observational study of ixazomib plus lenalidomide-dexamethasone in patients with relapsed/refractory multiple myeloma in Japan.

Real-world studies permit inclusion of a more diverse patient population and provide more information on the effectiveness of treatments used in routine clinical practice. This prospective, multicenter, observational study investigated the effectiveness and safety of ixazomib plus lenalidomide and dexamethasone (IRd) in 295 patients with relapsed/refractory multiple myeloma (RRMM) in routine clinical practice in Japan. Patients had a median age of 74 years, 80.0% were aged ≥ 65 years, 42.0% had received ≥ 3 lines of prior treatment, and 28.5% were "frail" according to the International Myeloma Working Group frailty score. After a median follow-up of 25.0 months, median progression-free survival (PFS) was 15.3 (95% CI 12.4-19.5) months, while median overall survival was not reached. The overall response rate was 53.9%, and 31.5% of patients had a very good partial response or better. In the subgroup analysis, median PFS was better in patients with 1 versus 2 or ≥ 3 lines of prior treatment (29.0 vs 19.2 or 6.9 months) and paraprotein versus clinical relapse (16.0 vs 7.9 months), but median PFS was not notably affected by frailty score or age group. Dose adjustment was more frequent among patients aged > 75 years, especially early after IRd treatment initiation. Treatment-emergent adverse events (TEAEs) of any grade occurred in 84.4% of patients and 24.7% of patients discontinued treatment due to TEAEs; no new safety concerns were found. These findings suggest that oral IRd triplet regimen is an effective and tolerable treatment option for RRMM patients in real-world settings outside of clinical trials.ClinicalTrials.gov identifier: NCT03433001; Date of registration: 14 February 2018.

R-CHOP treatment for patients with advanced follicular lymphoma: Over 15-year follow-up of JCOG0203.

Anti-CD20 antibody in combination with chemotherapy extends overall survival (OS) in untreated advanced-stage follicular lymphoma (FL), yet the optimal associated therapy is unclear. Data on the cumulative incidence of secondary malignancies postrelapse after conventional immunochemotherapy are scarce. A long-term analysis of rituximab combined with cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) as first-line treatment was conducted in a randomised clinical trial. A six-cycle R-CHOP regimen was administered every 2 or 3 weeks without rituximab maintenance. A prespecified evaluation was conducted 15 years after the completion of enrolment, following initial analysis results that showed no significant differences in outcomes at the 3-year mark. In-depth analyses were performed on the cohort of 248 patients with FL who were allocated to the two treatment arms. With a median follow-up period of 15.9 years, the 15-year OS was 76.2%. There were no protocol treatment-related deaths, nor were there any fatal infections attributable to subsequent lymphoma treatment. At 15 years, the cumulative incidence of non-haematological and haematological malignancies was 12.8% and 3.7% respectively. Histological transformation appeared after a median of 8 years. R-CHOP maintains safety and efficacy in patients with advanced FL over extended follow-up, making it a viable first-line option for patients with advanced-stage FL.