Follicular lymphoma grade 3: review and updates

Comparison of first-line treatment with bendamustine plus rituximab versus R-CHOP for patients with follicular lymphoma grade 3A: Results of a retrospective study from the Fondazione Italiana Linfomi

In the setting of follicular lymphoma (FL), frontline therapy with rituximab, cyclophosphamide, doxorubicin, and prednisone (R-CHOP) has represented for many years the standard of care for patients with symptomatic advanced disease. More recently, the combination of bendamustine plus rituximab (R-B) has emerged as an alternative therapeutic option. We present a retrospective, multicenter, observational study aimed at comparing outcomes and toxicities observed in 145 patients diagnosed with grade 3A FL treated with a first line therapy in 15 Italian Fondazione Italiana Linfomi centers between the 1st of January 2014 and the 30th of May 2018. Seventy patients were treated with R-B and 75 with R-CHOP. In the R-B group, the median age at the time of diagnosis was 67 years compared with 59 years in the R-CHOP group. Patients in R-B group achieved a similar overall response rate (96% vs. 99%) and a better complete remission rate (87% vs. 80%, p=0.035) compared with patients in R-CHOP group. Progression free survival (PFS) was similar between individual treated with R-CHOP and R-B (48- month PFS 77.7% vs. 76.6% respectively, p=0.745). The overall survival was significantly longer with R-CHOP treatment (HR=0.16; 95% IC, 0.04-0.74; p=0.007); however, no statistical significant difference was observed after adjustment for age. With the limitations of the study design, our results suggest that both R-B and R-CHOP seem to be valid first-line treatment options in FL3A.

Differences in clinical characteristics and outcomes between patients with grade 3a and grades 1-2 follicular lymphoma: a real-world multicenter study

BACKGROUND

The difference between clinical characteristics and outcomes between follicular lymphoma grade 1-2 (FL1-2) and FL3a defined pathologically remains unclear, resulting in uncertainty how to treat FL3a. However, it may be crucial for clinicians to discriminate grade 3a and grade 1-2 for predicting prognosis and thus making treatment decisions.

METHODS

We compared 1403 patients with FL1-2 and 765 patients with FL3a diagnosed between January 2000 and December 2020 from fifteen centers nationwide in China to describe differences in clinical characteristics and outcomes.

RESULTS

Compared with FL1-2 patients, FL3a subgroup had a higher percentage of elderly patients (P = 0.003), and relatively more FL3a patients presented with increased levels of LDH (P < 0.0001) and higher Ki-67 indexs greater than 30% (P < 0.001). More FL3a patients were treated with CHOP ± R (P < 0.0001), and fewer were treated with the watchful-waiting approach (P < 0.0001). The results showed a higher incidence of relapse among FL3a patients, in which more patients underwent histological transformation (HT) when compared to FL1-2 (P = 0.003). 1470 (76.2%) patients of the entire cohort received R-CHOP therapy; survival analysis revealed that FL3a patients had a worse progression-free survival (PFS) rate than FL1-2 patients. Survival of FL3a patients with respect to FLIPI showed an inferior PFS in the intermediate and high-risk groups than FL1-2 patients. FL3a patients had a much worse prognosis than FL1-2 with or without progression of disease within 24 months (POD24). FL3a patients had higher likelihood of lymphoma-related death (LRD, P < 0.05), whereas the rates for non-LRD were comparable.

CONCLUSION

In conclusion, this study demonstrates a marked difference in clinical features and outcomes in FL3a patients compared with FL1-2 patients. The results highlight the need for applying therapeutic approaches distinct from FL1-2 when treating FL3a patients.

Prediction of prognosis and pathologic grade in follicular lymphoma using 18F-FDG PET/CT

Purpose

We investigated the utility of a new baseline PET parameter expressing lesion dissemination and metabolic parameters for predicting progression-free survival (PFS) and pathologic grade in follicular lymphoma (FL).

Methods

The baseline ¹⁸F-FDG PET/CT images of 126 patients with grade 1–3A FL were retrospectively analyzed. A novel PET/CT parameter characterizing lesion dissemination, the distance between two lesions that were furthest apart (D_max), was calculated. The total metabolic tumor volume and total lesion glycolysis (TLG) were computed by using 41% of the maximum standardized uptake value (SUV_max) thresholding method.

Results

The 5-year PFS rate was 51.9% for all patients. In the multivariate analysis, high D_max [P = 0.046; hazard ratio (HR) = 2.877], high TLG (P = 0.004; HR = 3.612), and elevated serum lactate dehydrogenase (P = 0.041; HR = 2.287) were independent predictors of PFS. A scoring system for prognostic stratification was established based on these three adverse factors, and the patients were classified into three risk categories: low risk (zero to one factor, n = 75), intermediate risk (two adverse factors, n = 29), and high risk (three adverse factors, n = 22). Patients in the high-risk group had a shorter 3-year PFS (21.7%) than those in the low- and intermediate-risk groups (90.6 and 44.6%, respectively) (P < 0.001). The C-index of our scoring system for PFS (0.785) was superior to the predictive capability of the Follicular Lymphoma International Prognostic Index (FLIPI), FLIPI2, and PRIMA-Prognostic Index (C-index: 0.628–0.701). The receiver operating characteristic curves and decision curve analysis demonstrated that the scoring system had better differentiation and clinical utility than these existing indices. In addition, the median SUV_max was significantly higher in grade 3A (36 cases) than in grades 1 and 2 FL (90 cases) (median: 13.63 vs. 11.45, P = 0.013), but a substantial overlap existed (range: 2.25–39.62 vs. 3.17–39.80).

Conclusion

TLG and D_max represent two complementary aspects of the disease, capturing the tumor burden and lesion dissemination. TLG and D_max are promising metrics for identifying patients at a high risk of progression or relapse. Additionally, SUV_max seems to have some value for distinguishing grade 3A from low-grade FL but cannot substitute for biopsy.

A Favorable Outcome of Grade 3 Follicular Lymphoma Treated With Surgery and Obinutuzumab Combined With Chemotherapy: A Case Report and Literature Review

Follicular lymphoma is the most common type of low-grade non-Hodgkin lymphoma and the second most common type of lymphoma. Primary extranodal follicular lymphoma is rare compared with nodular follicular lymphoma involving the gastrointestinal (GI) tract. There has been uncertainty regarding follicular lymphomas due to the heterogeneous presentation and severity in which they present. However, studies showed that patients diagnosed with primary gastrointestinal follicular lymphoma do not typically differ in their presentation from those diagnosed with nodular follicular lymphoma involving the GI tract. Furthermore, recent literature identifies that patients diagnosed with grade 3 follicular lymphoma tend to have similar genetic and molecular entities to those diagnosed with diffuse large B-cell lymphoma (DLBCL). Based on these results, current studies have shown that patients with grade 3 follicular lymphoma who are treated with anthracycline-based regimens have similar outcomes to those with diffuse large B-cell lymphoma. However, additional studies are warranted to demonstrate the benefit of managing grade 3 follicular lymphoma with more aggressive anthracycline/rituximab-based regimens. Here, we present a case of a 44-year-old male diagnosed with grade 3 follicular lymphoma involving the gastrointestinal tract, who demonstrated an excellent treatment response following therapy similar to the treatment of bulky diffuse large B-cell lymphoma despite a tumor burden size below 7.5 cm.

High-grade Follicular Lymphomas Exhibit Clinicopathologic, Cytogenetic, and Molecular Diversity Extending Beyond Grades 3A and 3B

Although follicular lymphoma (FL) is usually graded as FL1-2, FL3A, and FL3B, some borderline cases can be observed and led us to investigate the clinicopathologic diversity of grade 3 FL (FL3). Among 2449 FL patients enrolled in Lymphoma Study Association (LYSA) trials, 1921 cases with sufficient material underwent a central pathologic review. The resulting diagnoses comprised 89.6% FL1-2 (n=1723), 7.2% FL3A (n=138), and 0.5% purely follicular FL3B (n=9). The remaining 51 unclassifiable cases (2.7%) exhibited high-grade features but did not meet WHO criteria for either FL3A or FL3B; and were considered as "unconventional" high-grade FL (FL3U). FL3U morphological pattern consisted of nodular proliferation of large cleaved cells or small-sized to medium-sized blast cells. Compared with FL3A, FL3U exhibited higher MUM1 and Ki67 expression, less BCL2 breaks and more BCL6 rearrangements, together with a higher number of cases without any BCL2, BCL6 or MYC rearrangement. FL3U harbored less frequent mutations in BCL2, KMT2D, KMT2B, and CREBBP than FL3A. MYC and BCL2 were less frequently mutated in FL3U than FL3B. Rituximab cyclophosphamide, doxorubicin, vincristine, and prednisone treated FL3U patients had a worse survival than FL1-2 patients with similar follicular lymphoma international prognostic index and treatment. These results suggest that high-grade FLs encompass a heterogeneous spectrum of tumors with variable morphology and genomic alterations, including FL3U cases that do not strictly fit WHO criteria for either FL3A or FL3B, and display a worse outcome than FL1-2. The distinction of FL3U may be useful to allow a better comprehension of high-grade FLs and to design clinical trials.

Long-term outcome comparing histological grades of follicular lymphoma patients treated with immunochemotherapy as first-line therapy: A retrospective analysis from two institutions

OBJECTIVES

To clarify the impact of histological grades in follicular lymphoma.

METHODS

We retrospectively analysed 250 patients diagnosed with FL treated with chemoimmunotherapy: 188 patients were grades 1-2 and 62 grade 3A.

RESULTS

In our series, grade 3A FL patients were older, higher proportion of localised disease and lower bone marrow infiltration at diagnosis comparing grades 1-2 FL patients. Estimated six-year progression-free survival and time to progression showed no differences between both groups [grade 3A: 56% (95%CI: 39%-73%) and 51% (95%CI: 41%-61%) vs grades 1-2:55% (95%CI: 46%-63%) and 57% (95%CI: 49%-65%), P = .782 and P = .521, respectively]. Estimated six-year overall survival was lower, 76% (95%CI: 64%-88%) for the grade 3A group than grades 1-2 83% (95%CI: 77%-89%); P = .044. In addition to that, cumulative incidence curves of death not related to lymphoma at 10 years between groups were as follows: [0.26 (95%CI: 0.25-0.27) and 0.05 (95%CI: 0.04-0.06) for G3AFL and G1-2FL, respectively], P = .010. Grade 3A FL showed in PFS curve no relapses after 6 years. These results were absolutely reproduced in 199 patients receiving R-CHOP regimen as induction.

CONCLUSIONS

Our results indicate similar long-term outcomes in terms of progression-free survival and time to progression in grades 1-2 and 3A. No relapses were observed in G3AFL group after 6 years.

Multicenter Analysis of Advanced Stage Grade 3A Follicular Lymphoma Outcomes by Frontline Treatment Regimen

BACKGROUND

Follicular lymphoma (FL) is a common form of non-Hodgkin lymphoma with a wide spectrum of presentation. While grade 1/2 FL is considered low grade and grade 3B FL is approached as an aggressive lymphoma, the management of grade 3A FL remains controversial.

PATIENTS AND METHODS

We performed a retrospective, multicenter analysis of patients aged ≥ 18 years with advanced stage 3/4 grade 3A FL diagnosed between January 2006 and July 2016. Patients were stratified by frontline chemotherapy regimen: anthracycline based (ATC), bendamustine (BD), and cyclophosphamide, vincristine, and prednisone (CVP). A total of 103 patients were identified from 6 contributing centers: 65 patients received ATC chemotherapy, 30 BD, and 8 CVP. The primary outcome was time to progression (TTP). Secondary outcomes included progression-free survival, overall survival, complete response rates, large cell transformation, and impact of standardized maximum uptake value on positron emission tomography/computed tomography with outcomes. Patient characteristics were similar among the 3 treatment groups.

RESULTS

For TTP at 24 months from initiation of treatment, 72% of ATC, 79% of BD, and 50% of CVP patients had not experienced disease progression (P = .01). Multivariate analysis demonstrated a TTP benefit for ATC compared to CVP (hazard ratio 3.22; 95% confidence interval, 1.26-8.25; P = .01) but no difference when compared to BD. Similar findings were seen with progression-free survival. While overall survival was similar among the 3 arms, there was a higher risk of large cell transformation following BD and CVP. Last, standardized maximum uptake value on positron emission tomography/computed tomography did not affect TTP when comparing BD- and ATC-treated patients.

CONCLUSION

Although ATC was superior to CVP, clinical outcomes (TTP, progression-free survival, and overall survival) were similar compared to BD chemotherapy for patients with grade 3A FL.

[Clinical characteristics and survival analysis of de novo grade 3 or transformed follicular lymphoma patients]

Objective: To evaluate the clinical characteristics and survival outcomes of patients with de novo grade 3 or transformed follicular lymphoma (FL). Methods: Fifty-two patients treated at Peking University Cancer Hospital between January 2009 and September 2017 were assessed, including 28 patients with FL 3A grade, 13 patients with FL 3B grade, 11 patients with transformed FL. Baseline characteristics, survival and prognostic factors were analyzed. Results: ① Twenty-six male and 26 female patients were enrolled, including 28 patients with FL 3A grade, 13 patients with FL 3B grade, 11 patients with transformed FL. ②The 3-year progression-free survival (PFS) and overall survival (OS) for the entire cohort were 56.0% and 80.6%, respectively. Patients with international prognostic index (IPI) score 0-1 demonstrated significantly better 3-year PFS (80.3% vs 20.1%; t=18.902, P<0.001) and OS (95.7% vs 57.0%; t=10.406, P<0.001) than patients with IPI score 2-3. Three-year PFS (94.1% vs 37.2% vs 25.2%; P=0.002) and OS (100.0% vs 76.0% vs 59.8%; P=0.020) were also significantly different among patients with FLIPI 1 score 0-1, 2, ≥3. FLIPI 2 score was also identified as a prognostic factor for 3-year PFS (68.4%, 0, 0; P=0.001) and OS(87.5%, 76.2%, 0; P=0.003). ③Multivariate analysis indicated a significant association of PFS (HR=3.536, P=0.015) and OS (HR=15.713, P=0.015) with IPI. FLIPI 2 was associated with OS (score 0-1, HR=0.078, P=0.007; score 2, HR=0.080, P=0.022). Conclusion: De novo grade 3 or transformed FL might be a group of curable disease with current treatment strategies. IPI is still a prognostic tool in this scenario.