Differential Diagnosis for Anaplastic Large Cell Lymphoma (ALCL) ALK Negative and Peripheral T-Cell Lymphoma
- Single Most Likely Diagnosis
- Peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS): This diagnosis is considered the most likely due to the overlap in clinical presentation and histological features between ALCL ALK negative and PTCL-NOS. Both can present with systemic symptoms, lymphadenopathy, and similar cytological features, making differentiation challenging without specific markers.
- Other Likely Diagnoses
- Angioimmunoblastic T-cell lymphoma (AITL): AITL can mimic ALCL and PTCL-NOS in its presentation, with systemic symptoms and lymphadenopathy being common. The presence of certain histological features such as follicular helper T-cell markers can help in differentiation.
- Adult T-cell leukemia/lymphoma (ATLL): Although less common, ATLL should be considered, especially in patients from endemic areas or with a history of HTLV-1 infection. The clinical presentation can be aggressive and similar to that of ALCL or PTCL-NOS.
- Do Not Miss Diagnoses
- Hodgkin lymphoma (classical or nodular lymphocyte-predominant): Although less likely, missing a diagnosis of Hodgkin lymphoma could have significant implications for treatment and prognosis. Certain subtypes, especially the nodular lymphocyte-predominant type, can have a similar clinical presentation to ALCL or PTCL-NOS.
- Cutaneous T-cell lymphoma (e.g., mycosis fungoides/Sézary syndrome): In cases where skin involvement is prominent, cutaneous T-cell lymphomas should be considered to avoid missing a potentially more indolent but treatable condition.
- Rare Diagnoses
- Extranodal natural killer/T-cell lymphoma, nasal type: This rare and aggressive lymphoma can present with similar symptoms, especially if there is extranodal involvement. Its consideration is crucial due to its distinct treatment approach and poor prognosis if not recognized early.
- Enteropathy-associated T-cell lymphoma (EATL): Although rare, EATL should be considered in patients with a history of celiac disease or those presenting with gastrointestinal symptoms, as it requires a specific therapeutic approach.