Our patient was found to have systemic anaplastic lymphoma kinase (ALK) positive anaplastic large cell lymphoma (ALCL).
ALK-positive ALCL is a rare, mature T-cell non-Hodgkin lymphoma (NHL).
Key learning points:
- 3% of all adult NHL
- 10 – 20% of all childhood NHL
- More common in males 1.5:1 (male:female)
- Commonly occurs before the age of 30
2. Clinical features
- Frequently involves extranodal sites such as skin, soft tissue, liver, lung, bone
- Rarely involves the mediastinum, gut or CNS
- Majority of patients present with advanced disease (stage III/IV) ~70%
- Majority of patients present with B symptoms ~75%
- Lymphoid cells are usually large with abundant cytoplasms and pleiomorphic ‘horseshoe-shaped’ nuclei, this is known as then ‘common pattern’. Variant histology includes the small cell and lymphohistiocytic patterns.
- Pathological cells contain a chromosomal translocation that involves the ALK gene and express ALK protein and CD30.
- Risk stratification should be completed using IPI index
- ALK positivity is an important prognostic marker as 5 year overall survival is greater in patients with ALK+ ALCL (~80%) than in ALK- ALCL (50%), however this may reflect the comparatively younger patient age group, rather than ALK expression
- CHOP – cyclophosphamide, doxorubicin, vincristine, prednisone
- CHOEP – as above plus etoposide
- GDP – gemcitabine, dexamethasone, cisplatin
- Brentuximab vedotin (NICE approved in the UK for a minimum of 8 and maximum of 16 cycles)
- Brentuximab vedotin as 1st line therapy?
WHO classification of Tumours of haematopoietic and lymphoid tissues (2017) Swerdlow et. al.
The biology and management of systemic ALCL, Hapgood et. al. 2015 Jul 2;126(1):17-25. doi: 10.1182/blood-2014-10-567461