![]() ![]() Similar to PTCL, NOS, ALCL ALK− patients frequently have advanced stage disease with the involvement of extranodal sites and the presence of B symptoms at the time of diagnosis. ALK+ ALCL more commonly occurs in children and young adults with a median age of 34 years versus 58 years in ALK- ALCL. ALK+ and ALK− ALCL are heterogeneous diseases and the vastly different prognoses may be at least partially due to their different clinical presentations. The increased ALK expression is due to a translocation, usually t(2 5)(p23 q35), which fuses the ALK gene on chromosome 2 with the nucleophosin gene on chromosome 5 resulting in constitutive activation of ALK, a tyrosine kinase receptor that is part of the insulin superfamily. 2 With rare exceptions, ALK is absent in normal human tissue, but immunohistochemistry shows positive ALK staining in the cytoplasm and nucleus of most ALK+ ALCL. ALCL is divided into ALK+ and ALK−, which have drastically different prognosis with 5 year overall survival of 70% versus 49%, respectively. Morphologically cells can be large to small but the classic “hallmark cell” is always present and has an eosinophilic region near an eccentric, kidney or horseshoe shaped nuclei. Unfortunately, with the exception of ALCL for which brentuximab vedotin will likely substantially change our approach to treatment, there are still many patients for whom available drugs will not be effective, and it is for these patients that further advances are urgently needed.ĪLCL is a CD30+ T cell neoplasm. ![]() These 4 drugs represent the first agents ever approved specifically for this indication. In the relapsed setting, major advances have occurred with Food and Drug Administration (FDA) approval of 4 new agents (pralatrexate, romidepsin, belinostat, brentuximab vedotin) for relapsed/refractory PTCL since 2009. Although autologous transplant in first remission is often used, its role as consolidation therapy in first remission remains unclear and may preferentially benefit low-risk patients. Even for those patients who do have a response to therapy, the risk of relapse remains quite high. Although current first line chemotherapy continues to be a CHOP-like (cyclophosphamide, doxorubicin, vincristine, prednisone) regimen there is now data suggesting that the addition of etoposide in younger patients improves outcomes. Peripheral T-cell lymphomas (PTCL), with the exception of anaplastic lymphoma kinase (ALK)-positive anaplastic large cell lymphoma (ALCL), have a very poor prognosis. ![]()
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