Differential Diagnosis for Lymphoma with Specific Immunophenotype
The presence of Reed-Sternberg cells along with a specific immunophenotype (CD30 and CD15 positive, CD45 negative) guides the differential diagnosis. Here's the organized differential diagnosis:
Single Most Likely Diagnosis
- Hodgkin Lymphoma (HL), Classical Type: This is the most likely diagnosis given the presence of Reed-Sternberg cells and the specific immunophenotypic profile (CD30 and CD15 positive, CD45 negative). These markers are characteristic of classical Hodgkin lymphoma, particularly the nodular sclerosis subtype.
Other Likely Diagnoses
- Anaplastic Large Cell Lymphoma (ALCL): Although less likely than classical HL due to the presence of Reed-Sternberg cells, ALCL can also be CD30 positive. However, it typically lacks Reed-Sternberg cells and has a different clinical presentation and prognosis.
- Lymphocyte-Predominant Hodgkin Lymphoma (LPHL): This subtype of HL is less likely given the immunophenotype, as LPHL typically expresses CD20 and lacks CD15 and CD30 expression on the lymphocytic and histiocytic (L&H) cells, also known as "popcorn" cells.
Do Not Miss Diagnoses
- Grey Zone Lymphoma: This is a rare and aggressive lymphoma that shares features of both classical Hodgkin lymphoma and diffuse large B-cell lymphoma. It can have a similar immunophenotype to classical HL but often has a more aggressive clinical course.
- Primary Mediastinal Large B-Cell Lymphoma: Although typically CD20 positive and CD30 variable, this diagnosis is crucial not to miss due to its distinct clinical presentation and potential for aggressive behavior.
Rare Diagnoses
- Non-Hodgkin Lymphoma with Reed-Sternberg-like Cells: Some non-Hodgkin lymphomas can rarely contain Reed-Sternberg-like cells, but these would not typically have the characteristic immunophenotype of classical HL.
- Metastatic Carcinoma: Very rarely, metastatic carcinomas can mimic lymphomas, including expressing CD30, but this would be extremely unusual and other clinical and pathological features would not support this diagnosis.