Anaplastic large cell lymphoma presenting as a cerebellar mass

Anaplastic large cell lymphoma [ALCL] is a T cell lymphoma occurring commonly in childhood and rarely in adults. Central nervous system involvement in ALCL is very rare and cerebellar involvement at presentation has never been described. We examine the case of a young adult who presented with a cerebellar mass. A 19-year-old boy presented with signs of raised intracranial tension, which, on imaging, revealed a right cerebellar mass. He underwent suboccipital craniotomy and partial excision of the tumor. However, the histopathology was inconclusive. He subsequently presented with cerebellar signs and repeat imaging showed recurrence of the cerebellar lesion. He underwent decompression and ventriculoperitoneal [VP] shunting. Histopathology was suggestive of ALK [anaplastic lymphoma kinase] positive anaplastic large cell lymphoma. The patient was started on chemotherapy. However, his neurological status deteriorated, his condition worsened, and he expired a month later

Leukemic phase of anaplastic lymphoma kinase positive, anaplastic large cell lymphoma.

Anaplastic large cell lymphoma (ALCL) is a distinct type of CD30+ T/null-cell non-Hodgkin's lymphoma that frequently involves nodal and extranodal sites. The presence of leukemic phase in ALCL is extremely rare and occurs exclusively with ALK1-positive ALCL. We describe two patients with ALK1-positive ALCL who developed a leukemic phase with rapid progression of the disease. Immunophenotypic pattern assessed on peripheral blood by flow cytometry revealed CD45, CD30, and CD25 positivity in both cases but NPM-ALK1 was expressed in only one case. Both patients developed leukemic phase as a terminal event of the disease and we share the immunophenotypic features of both cases.