obsolete monomorphic PTLD

Obsolescence of Monomorphic PTLD

Monomorphic PTLD, also known as post-transplant lymphoproliferative disorder, has undergone significant changes in its classification and understanding over the years.

• Classic Hodgkin lymphoma — PTLD type: This is the least common form of monomorphic PTLD. It was previously considered a distinct subtype but is now recognized as part of the broader spectrum of PTLD.
• Evolution of classification: The current classification of PTLD, based on the 2016 revision of the World Health Organization's lymphoid neoplasms, includes six subtypes. Monomorphic PTLD with DLBCL histology is the most common subtype, but its understanding has been largely extrapolated from studies in non-PTLD DLBCL.
• Shift towards polymorphic PTLD: The hypothesis suggests that there might be a progressive transition from early PTLD through polymorphic PTLD to monomorphic PTLD. This implies that polymorphic PTLD may be an intermediate stage, and further research is needed to confirm this.

Key Points

• Monomorphic PTLD was previously considered the most common subtype of PTLD.
• The current classification system recognizes six subtypes of PTLD, with monomorphic PTLD being one of them.
• The understanding of monomorphic PTLD has been largely extrapolated from studies in non-PTLD DLBCL.
• There is a hypothesis that polymorphic PTLD may be an intermediate stage between early PTLD and monomorphic PTLD.

References

[3] Monomorphic PTLD – Monomorphic PTLD are monoclonal lymphoid proliferations that meet the criteria for one of the B cell or T/NK cell lymphomas recognized in immunocompetent individuals. [5] The European Society for Blood and Marrow Transplantation (EBMT) has a classification system for PTLD, which includes monomorphic PTLD as one of the subtypes. [9] Most patients with monomorphic PTLD showed an aggressive histology, with 48 DLBCL-type and 2 Burkitt lymphoma cases reported.

Monomorphic Post-Transplant Lymphoproliferative Disorder (PTLD) Signs and Symptoms

Monomorphic PTLD, the most common type of PTLD, can manifest in various ways, ranging from mild to severe symptoms. According to medical literature [8][9], some of the signs and symptoms associated with monomorphic PTLD include:

• Organ failure: Monomorphic PTLD can lead to organ failure, such as liver or kidney failure, which can be life-threatening.
• Severe "late" disease: In its advanced stage, monomorphic PTLD can cause severe symptoms, including organ dysfunction or infectious complications [9].
• Weight loss and malaise: Patients with monomorphic PTLD may experience weight loss and general feelings of being unwell (malaise) [6][9].
• Fever: Fever is a common symptom in patients with monomorphic PTLD [5][7].

It's essential to note that the signs and symptoms of monomorphic PTLD can vary greatly, and these disorders can produce symptoms that resemble those of many other conditions [11]. Early detection and treatment are crucial for improving patient outcomes.

References:

[8] DP Beynet (2004) - Cited by 57 [9] AK Morgans (2010) - Cited by 34 [5] Y Zhang (2023) - Cited by 1 [7] X Zhang (2017) - Cited by 4

Diagnostic Tests for Obsolete Monomorphic Post-Transplant Lymphoproliferative Disorder (PTLD)

Monomorphic PTLD, a rare and aggressive form of post-transplant lymphoproliferative disorder, can be challenging to diagnose. While the "gold standard" for diagnosis remains tissue biopsy, several diagnostic tests can support the diagnosis.

• Histopathological examination: A surgical excisional or incisional biopsy is preferred to obtain a tissue specimen for histopathological examination (2). This test helps establish the diagnosis of PTLD and classify it according to the World Health Organization (WHO) 2017 criteria (3).
• Immunophenotypic approaches: Using morphologic and immunophenotypic approaches, researchers have studied cases of monomorphic PTLD, including a case that developed in the tongue following transplantation (6). These studies can provide valuable insights into the diagnosis and classification of PTLD.
• Clonality studies: Clonality studies can support the diagnosis by showing clonal immunoglobulin or T-cell receptor gene expression in monomorphic PTLDs (4, 7). This test can help confirm the presence of a monoclonal population of lymphocytes.

While these diagnostic tests are essential for supporting the diagnosis of obsolete monomorphic PTLD, it is crucial to note that the "gold standard" remains tissue biopsy. A combination of these tests and clinical evaluation by an experienced healthcare professional can provide a comprehensive understanding of the disease.

References: [2] M Markouli · 2022 · Cited by 10 [3] Y Zhang · 2023 [4] by LF Gonzalez-Cuyar · 2007 · Cited by 12 [6] by LF Gonzalez-Cuyar · 2007 · Cited by 12 [7] by D Dierickx · 2015 · Cited by 165

Based on the provided context, it appears that there are various treatment options for monomorphic post-transplant lymphoproliferative disorder (PTLD). Here's a summary of the relevant information:

• HD-MTX: High-dose methotrexate (HD-MTX) is an effective therapy for CNS PTLD and recurrent PTLD that have failed rituximab and CHOP chemotherapy [3].
• Rituximab: Rituximab can be used to target the CD20 antigen when lowering immunosuppression alone is unsuccessful. However, it's essential to note that patients not receiving rituximab induction had a significantly shorter mean PTLD-free survival time at 9 years follow-up [5].
• CHOP chemotherapy: CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) is a common chemotherapy regimen used to treat various types of lymphoma, including monomorphic PTLD. However, its effectiveness in treating PTLD is not explicitly stated in the provided context.
• Monoclonal antibody therapy: Monoclonal antibodies like rituximab can be effective in targeting B cells and reducing immunosuppression [4].
• Immunosuppression reduction: Limiting immunosuppression when permissible is a first-line treatment approach for PTLD, especially in cases where the EBV viral load is high [6].

It's essential to note that the most effective treatment approach may vary depending on individual patient factors and the specific characteristics of their monomorphic PTLD. A comprehensive review of the literature and consultation with an expert in the field are recommended to determine the best course of treatment.

References: [3] CJ Twist · 2013 · Cited by 10 — HD-MTX is an effective therapy for CNS PTLD and recurrent PTLD that have failed rituximab and CHOP chemotherapy. [4] by K Hickmann · 2024 — Since PTLD often involves B cells, monoclonal antibodies like rituximab can be used to target these cells and reduce immunosuppression. [5] Patients not receiving rituximab induction had a significantly shorter mean PTLD-free survival time at 9 years follow-up. [6] Limiting immunosuppression when permissible is a first-line treatment approach for PTLD, especially in cases where the EBV viral load is high.

Differential Diagnosis of Obsolete Monomorphic Post-Transplant Lymphoproliferative Disorders (PTLD)

Monomorphic PTLD, a rare and severe complication of hematopoietic or solid organ transplant recipients, can be challenging to diagnose due to its variable presentation. The differential diagnosis for obsolete monomorphic PTLD includes:

• Rejection of allograft organ: In the case of graft involvement, rejection should be considered in the differential diagnosis.
• Opportunistic infections: Various opportunistic infections can mimic the clinical presentation of PTLD and should be ruled out.
• Common infectious etiology: Common infectious causes such as bacterial, viral, or fungal infections should also be considered.

According to [10], given the highly variable presentation of PTLD, differential diagnosis should broadly be considered depending upon the patient's clinical presentation. Rejection of allograft organ, opportunistic infections, and common infectious etiology are among the key considerations in the differential diagnosis of obsolete monomorphic PTLD.

In addition, as mentioned in [9], it is essential to keep PTLD in the differential diagnosis of ill patients after transplant because their disease can range from being indolent to rapidly progressive. This highlights the importance of considering PTLD in the differential diagnosis, especially in cases where the clinical presentation is atypical or not responding to standard treatments.

References:

[9] AK Morgans (2010) - Cited by 34 [10] Context result 10