Follicular lymphoma: updates for pathologists

Recent developments in CD19-targeted therapies for follicular lymphoma

INTRODUCTION

CD19 has emerged as an important and novel therapeutic target in follicular lymphoma. CD19-directed therapies, including monoclonal antibodies, bispecific antibodies, and CAR T-cell therapies, offer promising avenues for treating follicular lymphoma and improving outcomes.

AREAS COVERED

We review the role and rationale of targeting CD19 in follicular lymphoma and different interventions of CD19 targeting, such as cell therapy, bispecific antibodies, antibody-drug conjugates, and monoclonal antibodies. We finalize with a discussion on how these therapies may influence the treatment landscape of follicular lymphoma.

EXPERT OPINION

CD19 is an attractive target for therapeutic development in follicular lymphoma. Given its effectiveness, it will continue to move forward as a promising therapy for this disease.

Concurrent identification of follicular lymphoma and papillary thyroid carcinoma

INTRODUCTION

PTC has high lymph node metastasis, affecting central and lateral lymph nodes. On the other hand, follicular lymphoma is the second most frequent non-Hodgkin lymphoma in the West and affects cervical lymph nodes.

CASE PRESENTATION

A 66-year-old Saudi man with type 2 diabetes and hypertension presented with neck lumps on both sides of his neck. The swelling was progressive, with no apparent cause, no history of hypothyroidism or hyperthyroidism, and no constitutional symptoms. Physical examination revealed multiple lymph node enlargements and a hard, firm mass on his thyroid gland.

CLINICAL DISCUSSION

Multiple malignant neoplasms are rare, but secondary primary cancers have been documented in patients with PTC. The occurrence of both cancers is commonly detected during follow-up and aided by modern imaging techniques. The main treatment for PTC is surgery, usually with a good prognosis.

CONCLUSION

A 66-year-old male was diagnosed with follicular lymphoma during a papillary thyroid carcinoma workup, emphasizing the importance of careful lymph node dissection and microscopic examination for rare cases.

Impact of Primary Disease Site of Involvement by Early-Stage Follicular Lymphoma on Patient Outcomes

INTRODUCTION

Follicular lymphoma is a common non-Hodgkin lymphoma that can start in a diverse array of tissues throughout the body. While the majority of patients may be able to live many years with this disease, cure remains very difficult to achieve.

OBJECTIVE

We sought to investigate the impact of follicular lymphoma primary disease site in early-stage disease on patient outcomes using a large national database.

METHODS

Baseline demographic and disease data for patients diagnosed with follicular lymphoma from 2000-2015 was identified and extracted from the NCI Surveillance, Epidemiology, and End Results (SEER) database. Primary disease sites were grouped into one of two cohorts: nodal disease (lymph nodes and spleen) and extranodal disease (everything else). Analysis was performed using summary statistics, Kaplan-Meier method, and Cox-proportional hazards models for univariate and multivariate analysis.

RESULTS

A total of 13,400 patients were included in the final analysis and the majority were non-Hispanic white (81%), with stage I (63%), and nodal FL (79%). Median overall survival for nodal disease was 15.1 years [95% CI (14.6-15.6)] while median overall survival for extranodal disease was 15.8 years [95% CI (14.9-16.3)]. Overall survival was slightly better for patients with extranodal disease [HR = 0.89, 95% CI (0.84-0.96); p-value = 0.00012]. This finding remained consistent after controlling for age and race [HR = 0.84, 95% CI (0.79-0.90); p-value <0.0001].

CONCLUSIONS

The primary site of involvement by early-stage follicular lymphoma may have an impact on patient outcomes and warrants further investigation.

Chronic pancreatitis for the clinician: complications and special forms of the disease. Interdisciplinary position paper of the Catalan Society of Digestology (SCD) and the Catalan Pancreatic Society (SCPanc)

Chronic pancreatitis tends to develop a number of complications that may constitute the form of presentation of the disease. Some societies have issued guidelines for diagnosis and treatment of chronic pancreatitis complications, but the level of evidence for any topic is usually low and recommendations tend to be weak. We aimed to provide defined position statements for the clinician based on updated review of published literature and on multidisciplinary expert agreement. The goal was to propose defined terminology and rational diagnostic/therapeutic circuits based on current knowledge. To this end 14 sections related to complications and special forms of chronic pancreatitis (early chronic, groove and autoimmune pancreatitis) were reviewed by 21 specialists from 6 different fields to generate 32 statements. Featured statements assert common bile duct stenosis does not require invasive treatment (endoscopic or surgical) unless cholestasis, cholangitis, lithiasis or other symptoms develop. Pancreatic duct strictures and calculi should be approached (after ruling out malignancy) if causing pain, pancreatitis, pseudocysts or other complications. Treatment of symptomatic pseudocysts must be individualized, considering associated main duct stenosis, vascular and pericystic complications. Higher risk conditions for pancreatic cancer are advance age, smoking, genetic background, recent diagnosis of chronic pancreatitis or diabetes, and appearance of new symptoms. Groove pancreatitis can initially be treated with conservative measures. Both prednisolone or rituximab can induce remission and maintenance of autoimmune pancreatitis. Internal fistula, vascular complications, bacterial overgrowth, osteoporosis and renal lithiasis require specific therapeutic approaches.

The follicular lymphoma tumor microenvironment at single-cell and spatial resolution

ABSTRACT

Follicular lymphoma (FL) is a generally incurable malignancy that originates from developmentally blocked germinal center B cells residing, primarily, within lymph nodes (LNs). During the long natural history of FL, malignant B cells often disseminate to multiple LNs and can affect virtually any organ. Nonmalignant LNs are highly organized structures distributed throughout the body, in which they perform functions critical for host defense. In FL, the malignant B cells "re-educate" the lymphoid environment by altering the phenotype, distribution, and abundance of other cells such as T cells, macrophages, and subsets of stromal cells. Consequently, dramatic anatomical changes occur and include alterations in the number, shape, and size of neoplastic follicles with an accompanying attenuation of the T-cell zone. Ongoing and dynamic interactions between FL B cells and the tumor microenvironment (TME) result in significant clinical heterogeneity observed both within and across patients. Over time, FL evolves into pathological variants associated with distinct outcomes, ranging from an indolent disease to more aggressive clinical courses with early death. Given the importance of both cell-intrinsic and -extrinsic factors in shaping disease progression and patient survival, comprehensive examination of FL tumors is critical. Here, we describe the cellular composition and architecture of normal and malignant human LNs and provide a broad overview of emerging technologies for deconstructing the FL TME at single-cell and spatial resolution. We additionally discuss the importance of capturing samples at landmark time points as well as longitudinally for clinical decision-making.

Analysis of immunophenotypic features in hyaline vascular type Castleman disease

BACKGROUND

Studies suggested that the immunophenotype of hyaline vascular type Castleman disease (HVCD) lacked characteristics, which was easy to be confused with other diseases.

METHODS

From January 2010 to June 2022, 17 cases of HVCD were selected from the Department of Pathology of Shaanxi Provincial People's Hospital and the Department of Pathology of Shaanxi Provincial Cancer Hospital. 13 cases of reactive hyperplastic lymph nodes (RHL) and 11 cases of follicular lymphoma (FL) were selected as the control group. All cases were performed CD3, CD20, CD21 and BCL2 immunohistochemical staining.

RESULTS

(i) In 17 cases of HVCD, the negative area of BCL2 of germinal center was significantly smaller than the negative area of CD3 of germinal center. However, in 13 cases of RHL, the negative area of CD3 of germinal center was basically consistent with the negative area of germinal center of BCL2 of germinal center. In 11 cases of FL, in neoplastic follicles, the negative area of CD3 was basically consistent with the positive area of BCL2. The difference between HVCD group and other two groups of diseases was statistically significant (P < 0.05). (ii) In 17 cases of HVCD, the negative area of BCL2 of germinal center was significantly smaller than the follicular dendritic cell (FDC) meshworks expressed by CD21. However, in 13 cases of RHL, the FDC meshworks expressed by CD21 were basically consistent with the negative area of BCL2 of germinal center. In 11 cases of FL, in neoplastic follicles, the FDC meshworks expressed by CD21 was basically consistent with the positive area of BCL2. The difference between HVCD group and other two groups of disease was statistically significant (P < 0.05).

CONCLUSIONS

HVCD has unique immunophenotypic characteristics. The negative area of BCL2 of germinal center is significantly smaller than the negative area of CD3. The negative area of the BCL2 of germinal center is significantly smaller than the FDC meshworks expressed by CD21. These two immunophenotypic features in HVCD are very important in diagnosis and differential diagnosis.

A rare case of follicular lymphoma of the bladder

This case details a 69-year-old female with a 3cm bladder mass on imaging who underwent transurethral resection of the bladder with pathology revealing non-Hodgkin follicular lymphoma to the bladder. The rarity and complexity of this presentation generated a challenging treatment dilemma regarding surveillance and active treatment.

Clinical features and prognostic factors in 49 patients with follicular lymphoma at a single center: A retrospective analysis

BACKGROUND

Follicular lymphoma (FL) is a type of B-cell lymphoma that originates at the germinal center and has a low malignancy rate. FL has become the most common inert lymphoma in Europe and America but has a relatively low incidence in Asia.

AIM

To explore the clinical features, curative effects, and prognostic factors of FL.

METHODS

Completed medical records of 49 patients with FL who were admitted to the Ningbo First Hospital from June 2010 to June 2021 were examined. These patients were definitively diagnosed by pathological biopsy or immunohistochemical staining. The diagnostic criteria were based on the 2008 World Health Organization classification of lymphomas. Ann Arbor staging was performed according to the imaging and bone marrow examination results. Risk stratification of all patients was performed based on the International Prognostic Index (IPI), age-adjusted IPI, Follicular Lymphoma International Prognosis Index (FLIPI), and FLIPI2 to compare the efficacy of different treatment regimens and analyze the related prognostic factors.

RESULTS

The age of onset in patients ranged from 24 to 76 years, with a median age of 51 years. Most patients developed the disease at 40–59 years of age, and the male:female ratio was 1.6:1. No significant difference was noted in the curative effect between the non-chemotherapy, combined chemotherapy, and other chemotherapy regimens (P > 0.05). Hemoglobin (Hb) level < 120 g/L, Ki-67 value > 50%, bone marrow involvement, and clinical stages III–IV were associated with a poor prognosis of FL (P < 0.05). However, the influence of other indicators was not statistically significant. Risk grouping was performed using the FLIPI, and the results showed that 24.5%, 40.8%, and 34.7% of patients were in the low-, moderate-, and high-risk groups, respectively. According to the survival analysis results, the survival rate of patients was lower in the high-risk group than in the other low-risk and moderate-risk groups (P < 0.05).

CONCLUSION

FL mainly occurs in middle-aged and elderly men, primarily affecting lymph nodes and bone marrow. Hb level, Ki-67 value, bone marrow involvement, and clinical staging were used to evaluate prognosis.

A review of the totality of evidence in the development of ABP 798, a rituximab biosimilar

ABP 798 (RIABNI™) is a biosimilar to rituximab reference product (RP), a monoclonal antibody that targets CD20. Approval of ABP 798 was based on the totality of evidence generated using a stepwise approach which began by showing that it is structurally and functionally similar to rituximab RP. This analytical assessment was followed by a demonstration of pharmacokinetic/pharmacodynamic similarity in patients with rheumatoid arthritis. Comparative clinical efficacy and safety of ABP 798 with rituximab RP was demonstrated as a final step in patients with non-Hodgkin lymphoma and in those with rheumatoid arthritis. Overall, the totality of evidence supported the conclusion that ABP 798 is highly similar to rituximab RP and provided scientific justification for extrapolation to other approved indications of rituximab RP.

Follicular Lymphoma of Breast: A Case Report from Pakistan

Introduction

Breast lymphoma (BL) is a rare breast tumour and accounts for <1% of all breast malignancies. It is further categorised into primary BL and secondary BL. This manuscript presents a case report of a patient diagnosed with secondary BL.

Case Description

A 51-year-old female presented in the one-stop breast clinic with 6-month history of having a static and painless left breast lump. Mass was firm, non-tender and 2 cm in size. It was not adherent to skin or muscle and it was present in the upper outer quadrant of the left breast. Mammo-sonography revealed a circumscribed mass of 17 mm in the outer quadrant of the left breast. There were enlarged ipsilateral lymph nodes. Core biopsy suggested atypical lymphoid infiltrates. She underwent wide local excision of breast and axillary nodal mass. The definitive histological diagnosis revealed non-Hodgkin's follicular lymphoma grade 2/3. Staging computed tomography scan features were suggestive of cervical lymphadenopathy. Hence, staging workup proved this to be a case of secondary BL.

Practical Implication

The early diagnosis of BL is highly relevant. Its diagnosis is challenging due to non-specific clinical presentation and imaging features. Commonly FL is diagnosed on excisional biopsy or after wide local breast mass excision. Primary and secondary lymphomas, though rare, should be considered in the differential diagnosis of breast malignancies.