Hypocellular/lymphohistiocytic variant of Anaplastic Large Cell Lymphoma of lymph node, mimicking granulation tissue

Area of Science:

• Hematology
• Oncology
• Pathology

Background:

• Anaplastic Large Cell Lymphoma (ALCL) is a distinct subtype of T/null cell non-Hodgkin lymphoma (NHL) within the WHO classification.
• The Lymphohistiocytic (LH) variant of ALCL comprises approximately 10% of all ALCL cases.
• This variant is characterized by numerous reactive histiocytes, which can obscure the neoplastic cells, potentially leading to misdiagnosis as reactive lymphadenopathy.

Observation:

• A case study of a 16-year-old female patient is presented.
• The patient was diagnosed with a hypocellular Lymphohistiocytic (LH) variant of ALCL.
• An unusual histological feature, resembling granulation tissue, was noted in the presentation.

Findings:

• The presence of abundant histiocytes in LH variant ALCL can mask the underlying malignancy.
• The unusual granulation tissue-like appearance in this case presented a diagnostic challenge.
• Differential diagnosis is crucial, especially in pediatric and adolescent populations presenting with atypical lymphadenopathy.

Implications:

• This case underscores the necessity of including ALCL in the differential diagnosis for young patients with unusual or atypical reactive lymphadenopathy.
• Awareness of the diverse histological presentations of ALCL, including the LH variant, is critical for accurate diagnosis.
• Prompt and correct diagnosis of ALCL is essential for appropriate patient management and treatment planning.